EyeLink Eye Trackers in EEG, fNIRS, and TMS Publications

@article{MacKey2017,

title = {Distinct contributions by frontal and parietal cortices support working memory},

author = {Wayne E. MacKey and Clayton E. Curtis},

doi = {10.1038/s41598-017-06293-x},

year  = {2017},

date = {2017-01-01},

journal = {Scientific Reports},

volume = {7},

pages = {6188},

publisher = {Springer US},

abstract = {Although subregions of frontal and parietal cortex both contribute and coordinate to support working memory (WM) functions, their distinct contributions remain elusive. Here, we demonstrate that perturbations to topographically organized human frontal and parietal cortex during WM maintenance cause distinct but systematic distortions in WM. The nature of these distortions supports theories positing that parietal cortex mainly codes for retrospective sensory information, while frontal cortex codes for prospective action.},

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@article{Mathew2017,

title = {Limited contribution of primary motor cortex in eye-hand coordination: A TMS study},

author = {James Mathew and Alexandre Eusebio and Frederic R. Danion},

doi = {10.1523/JNEUROSCI.0564-17.2017},

year  = {2017},

date = {2017-01-01},

journal = {Journal of Neuroscience},

volume = {37},

number = {40},

pages = {9730 –9740},

abstract = {The ability to track a moving target with the eye is substantially improved when the target is self-moved compared with when it is moved by an external agent. To account for this observation, it has been postulated that the oculomotor system has access to hand efference copy, thereby allowing to predict the motion of the visual target. Along this scheme, we tested the effect of transcranial magnetic stimulation (TMS) over the hand area of the primary motor cortex (M1) when human participants (50% females) are asked to track with their eyes a visual target whose horizontal motion is driven by their grip force. We reasoned that, if the output of M1 is used by the oculomotor system to keep track of the target, on top of inducing short latency disturbance of grip force, single-pulse TMS should also quickly disrupt ongoing eye motion. For comparison purposes, the effect of TMS over M1 was monitored when subjects tracked an externally moved target (while keeping their hand at rest or not). In both cases, results showed no alterations in smooth pursuit, meaning that its velocity was unaffected within the 25-125 ms epoch that followed TMS. Overall, our results imply that the output of M1 has limited contribution in driving the eye motion during our eye-hand coordination task. This study suggests that, if hand motor signals are accessed by the oculomotor system, this is upstream of M1.},

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@article{Paladini2017,

title = {The influence of alertness on the spatial deployment of visual attention is mediated by the excitability of the posterior parietal cortices},

author = {Rebecca E. Paladini and René M. Müri and Jurka Meichtry and Tobias Nef and Fred W. Mast and Urs P. Mosimann and Thomas Nyffeler and Dario Cazzoli},

doi = {10.1093/cercor/bhw390},

year  = {2017},

date = {2017-01-01},

journal = {Cerebral Cortex},

volume = {27},

number = {1},

pages = {233–243},

abstract = {With a reduced level of alertness, healthy individuals typically show a rightward shift when deploying visual attention in space. The impact of alertness on the neural networks governing visuospatial attention is, however, poorly understood. By using a transcranial magnetic stimulation twin-coil approach, the present study aimed at investigating the effects of an alertness manipulation on the excitability of the left and the right posterior parietal cortices (PPCs), crucial nodes of the visuospatial attentional network. Participants' visuospatial attentional deployment was assessed with a free visual exploration task and concurrent eye tracking. Their alertness level was manipulated through the time of the day, that is, by testing chronotypically defined evening types both during their circadian on- and off-peak times. The results revealed an increased excitability of the left compared with the right PPC during low alertness. On the horizontal dimension, these results were accompanied by a significant rightward shift in the center and a bilateral narrowing in the periphery of the visual exploration field, as well as a central upward shift on the vertical dimension. The findings show that the manipulation of non-spatial attentional aspects (i.e., alertness) can affect visuospatial attentional deployment and modulate the excitability of areas subtending spatial attentional control.},

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@article{Aine2017,

title = {Multimodal neuroimaging in schizophrenia: Description and dissemination},

author = {C. J. Aine and H. J. Bockholt and J. R. Bustillo and J. M. Cañive and A. Caprihan and C. Gasparovic and F. M. Hanlon and J. M. Houck and R. E. Jung and J. Lauriello and J. Liu and A. R. Mayer and N. I. Perrone-Bizzozero and S. Posse and Julia M. Stephen and J. A. Turner and V. P. Clark and Vince D. Calhoun},

doi = {10.1007/s12021-017-9338-9},

year  = {2017},

date = {2017-01-01},

journal = {Neuroinformatics},

volume = {15},

number = {4},

pages = {343–364},

publisher = {Neuroinformatics},

abstract = {In this paper we describe an open-access collection ofmultimodal neuroimaging data in schizophrenia for release to the community. Data were acquired from approximately 100 patients with schizophrenia and 100 age-matched controls during rest as well as several task activation paradigms targeting a hierarchy of cognitive constructs. Neuroimaging data include structural MRI, functional MRI, diffusion MRI, MR spectroscopic imaging, and magnetoencephalography. For three of the hypothesis-driven projects, task activation paradigms were acquired on subsets of~200 volunteers which examined a range of sensory and cognitive processes (e.g., auditory sensory gating, auditory/visual multisensory integration, visual transverse patterning). Neuropsychological data were also acquired and genetic material via saliva samples were collected from most of the participants and have been typed for both genome-wide polymorphism data as well as genome-wide methylation data. Some results are also present- ed from the individual studies as well as from our data-driven multimodal analyses (e.g., multimodal examinations of network structure and network dynamics and multitask fMRI data analysis across projects). All data will be released through the Mind Research Network's collaborative informatics and neuroimaging suite (COINS).},

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@article{Amoruso2017,

title = {Variability in functional brain networks predicts expertise during action observation},

author = {Lucía Amoruso and Agustín Ibáñez and Bruno Fonseca and Sebastián Gadea and Lucas Sedeño and Mariano Sigman and Adolfo M. García and Ricardo Fraiman and Daniel Fraiman},

doi = {10.1016/j.neuroimage.2016.09.041},

year  = {2017},

date = {2017-01-01},

journal = {NeuroImage},

volume = {146},

pages = {690–700},

publisher = {Elsevier},

abstract = {Observing an action performed by another individual activates, in the observer, similar circuits as those involved in the actual execution of that action. This activation is modulated by prior experience; indeed, sustained training in a particular motor domain leads to structural and functional changes in critical brain areas. Here, we capitalized on a novel graph-theory approach to electroencephalographic data (Fraiman et al., 2016) to test whether variability in functional brain networks implicated in Tango observation can discriminate between groups differing in their level of expertise. We found that experts and beginners significantly differed in the functional organization of task-relevant networks. Specifically, networks in expert Tango dancers exhibited less variability and a more robust functional architecture. Notably, these expertise-dependent effects were captured within networks derived from electrophysiological brain activity recorded in a very short time window (2 s). In brief, variability in the organization of task-related networks seems to be a highly sensitive indicator of long-lasting training effects. This finding opens new methodological and theoretical windows to explore the impact of domain-specific expertise on brain plasticity, while highlighting variability as a fruitful measure in neuroimaging research.},

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@article{Arazi2017,

title = {The magnitude of trial-by-trial neural variability Is reproducible over time and across tasks in humans},

author = {Ayelet Arazi and Gil Gonen-Yaacovi and Ilan Dinstein},

doi = {10.1523/ENEURO.0292-17.2017},

year  = {2017},

date = {2017-01-01},

journal = {eNeuro},

volume = {4},

number = {6},

pages = {1–12},

abstract = {Numerous studies have shown that neural activity in sensory cortices is remarkably variable over time and across trials even when subjects are presented with an identical repeating stimulus or task. This trial-by-trial neural variability is relatively large in the prestimulus period and considerably smaller (quenched) following stimulus presentation. Previous studies have suggested that the magnitude of neural variability affects behavior such that perceptual performance is better on trials and in individuals where variability quenching is larger. To what degree are neural variability magnitudes of individual subjects flexible or static? Here, we used EEG recordings from adult humans to demonstrate that neural variability magnitudes in visual cortex are remarkably consistent across different tasks and recording sessions. While magnitudes of neural variability differed dramatically across individual subjects, they were surprisingly stable across four tasks with different stimuli, temporal structures, and attentional/cognitive demands as well as across experimental sessions separated by one year. These experiments reveal that, in adults, neural variability magnitudes are mostly solidified individual characteristics that change little with task or time, and are likely to predispose individual subjects to exhibit distinct behavioral capabilities.},

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@article{Bache2017,

title = {10-month-old infants are sensitive to the time course of perceived actions: Eye-tracking and EEG evidence},

author = {Cathleen Bache and Anne Springer and Hannes Noack and Waltraud Stadler and Franziska Kopp and Ulman Lindenberger and Markus Werkle-Bergner},

doi = {10.3389/fpsyg.2017.01170},

year  = {2017},

date = {2017-01-01},

journal = {Frontiers in Psychology},

volume = {8},

pages = {1170},

abstract = {Research has shown that infants are able to track a moving target efficiently – even if it is transiently occluded from sight. This basic ability allows prediction of when and where events happen in everyday life. Yet, it is unclear whether, and how, infants internally represent the time course of ongoing movements to derive predictions. In this study, 10-month-old crawlers observed the video of a same-aged crawling baby that was transiently occluded and reappeared in either a temporally continuous or non-continuous manner (i.e., delayed by 500 ms vs. forwarded by 500 ms relative to the real-time movement). Eye movement and rhythmic neural brain activity (EEG) were measured simultaneously. Eye movement analyses showed that infants were sensitive to slight temporal shifts in movement continuation after occlusion. Furthermore, brain activity associated with sensorimotor processing differed between observation of continuous and non-continuous movements. Early sensitivity to an action's timing may hence be explained within the internal real-time simulation account of action observation. Overall, the results support the hypothesis that 10-month-old infants are well prepared for internal representation of the time course of observed movements that are within the infants' current motor repertoire.},

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@article{Bayer2017a,

title = {Independent effects of motivation and spatial attention in the human visual cortex},

author = {Mareike Bayer and Valentina Rossi and Naomi Vanlessen and Annika Grass and Annekathrin Schacht and Gilles Pourtois},

doi = {10.1093/scan/nsw162},

year  = {2017},

date = {2017-01-01},

journal = {Social Cognitive and Affective Neuroscience},

volume = {12},

number = {1},

pages = {146–156},

abstract = {Motivation and attention constitute major determinants of human perception and action. Nonetheless, it remains a matter of debate whether motivation effects on the visual cortex depend on the spatial attention system, or rely on independent pathways. This study investigated the impact of motivation and spatial attention on the activity of the human primary and extrastriate visual cortex by employing a factorial manipulation of the two factors in a cued pattern discrimination task. During stimulus presentation, we recorded event-related potentials and pupillary responses. Motivational relevance increased the amplitudes of the C1 component at ∼70 ms after stimulus onset. This modulation occurred independently of spatial attention effects, which were evident at the P1 level. Furthermore, motivation and spatial attention had independent effects on preparatory activation as measured by the contingent negative variation; and pupil data showed increased activation in response to incentive targets. Taken together, these findings suggest independent pathways for the influence of motivation and spatial attention on the activity of the human visual cortex.},

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@article{Bayer2017,

title = {The impact of personal relevance on emotion processing: Evidence from event-related potentials and pupillary responses},

author = {Mareike Bayer and Katja Ruthmann and Annekathrin Schacht},

doi = {10.1093/scan/nsx075},

year  = {2017},

date = {2017-01-01},

journal = {Social Cognitive and Affective Neuroscience},

volume = {12},

number = {9},

pages = {1470–1479},

abstract = {Emotional stimuli attract attention and lead to increased activity in the visual cortex. The present study investigated the impact of personal relevance on emotion processing by presenting emotional words within sentences that referred to participants' significant others or to unknown agents. In event-related potentials, personal relevance increased visual cortex activity within 100 ms after stimulus onset and the amplitudes of the Late Positive Complex (LPC). Moreover, personally relevant contexts gave rise to augmented pupillary responses and higher arousal ratings, suggesting a general boost of attention and arousal. Finally, personal relevance increased emotion-related ERP effects starting around 200 ms after word onset; effects for negative words compared to neutral words were prolonged in duration. Source localizations of these interactions revealed activations in prefrontal regions, in the visual cortex and in the fusiform gyrus. Taken together, these results demonstrate the high impact of personal relevance on reading in general and on emotion processing in particular.},

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@article{Burke2016,

title = {Dissociation of the rostral and dorsolateral prefrontal cortex during sequence learning in saccades: A TMS investigation},

author = {Melanie R. Burke and R. O. Coats},

doi = {10.1007/s00221-015-4495-2},

year  = {2016},

date = {2016-01-01},

journal = {Experimental Brain Research},

volume = {234},

number = {2},

pages = {597–604},

publisher = {Springer Berlin Heidelberg},

abstract = {This experiment sought to find whether differences exist between the dorsolateral prefrontal cortex (DLPFC) and the medial rostral prefrontal cortex (MRPFC) for performing stimulus-independent and stimulus-oriented tasks, respectively. To find a causal relationship in these areas, we employed the use of trans-cranial magnetic stimulation (TMS). Prefrontal areas were stimulated whilst participants performed random or predictable sequence learning tasks at stimulus onset (1st presentation of the sequence only for both Random and Predictable), or during the inter-sequence interval. Overall, we found that during the predictable task a significant decrease in saccade latency, gain and duration was found when compared to the randomised conditions, as expected and observed previously. However, TMS stimulation in DLPFC during the delay in the predictive sequence learning task reduced this predictive ability by delaying the saccadic onset and generating abnormal reductions in saccadic gains during prediction. In contrast, we found that stimulation during a delay in MRPFC reversed the normal effects on peak velocity of the task with the predictive task revealing higher peak velocity than the randomised task. These findings provide causal evidence for independent functions of DLPFC and MRPFC in performing stimulus-independent processing during sequence learning in saccades.},

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@article{Krall2016,

title = {The right temporoparietal junction in attention and social interaction: A transcranial magnetic stimulation study},

author = {Sarah C. Krall and Lukas J. Volz and Eileen Oberwelland and Christian Grefkes and Gereon R. Fink and Kerstin Konrad},

doi = {10.1002/hbm.23068},

year  = {2016},

date = {2016-01-01},

journal = {Human Brain Mapping},

volume = {37},

number = {2},

pages = {796–807},

abstract = {The right temporoparietal junction (rTPJ) has been associated with the ability to reorient attention to unexpected stimuli and the capacity to understand others' mental states (theory of mind [ToM]/false belief). Using activation likelihood estimation meta-analysis we previously unraveled that the anterior rTPJ is involved in both, reorienting of attention and ToM, possibly indicating a more general role in attention shifting. Here, we used neuronavigated transcranial magnetic stimulation to directly probe the role of the rTPJ across attentional reorienting and false belief. Task performance in a visual cueing paradigm and false belief cartoon task was investigated after application of continuous theta burst stimulation (cTBS) over anterior rTPJ (versus vertex, for control). We found that attentional reorienting was significantly impaired after rTPJ cTBS compared with control. For the false belief task, error rates in trials demanding a shift in mental state significantly increased. Of note, a significant positive correlation indicated a close relation between the stimulation effect on attentional reorienting and false belief trials. Our findings extend previous neuroimaging evidence by indicating an essential overarching role of the anterior rTPJ for both cognitive functions, reorienting of attention and ToM.},

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@article{Quentin2016,

title = {Visual contrast sensitivity improvement by right frontal high-beta activity is mediated by contrast gain mechanisms and influenced by fronto-parietal white matter microstructure},

author = {Romain Quentin and Seth E. Frankston and Marine Vernet and Monica N. Toba and Paolo Bartolomeo and Lorena Chanes and Antoni Valero-Cabré},

doi = {10.1093/cercor/bhv060},

year  = {2016},

date = {2016-01-01},

journal = {Cerebral Cortex},

volume = {26},

number = {6},

pages = {2381–2390},

abstract = {Behavioral and electrophysiological studies in humans and non-human primates have correlated frontal high-beta activity with the orienting of endogenous attention and shown the ability of the latter function to modulate visual performance. We here combined rhythmic transcranial magnetic stimulation (TMS) and diffusion imaging to study the relation between frontal oscillatory activity and visual performance, and we associated these phenomena to a specific set of white matter pathways that in humans subtend attentional processes. High-beta rhythmic activity on the right frontal eye field (FEF) was induced with TMS and its causal effects on a contrast sensitivity function were recorded to explore its ability to improve visual detection performance across different stimulus contrast levels. Our results show that frequency-specific activity patterns engaged in the right FEF have the ability to induce a leftward shift of the psychometric function. This increase in visual performance across different levels of stimulus contrast is likely mediated by a contrast gain mechanism. Interestingly, microstructural measures of white matter connectivity suggest a strong implication of right fronto-parietal connectivity linking the FEF and the intraparietal sulcus in propagating high-beta rhythmic signals across brain networks and subtending top-down frontal influences on visual performance.},

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@article{Wang2016e,

title = {Rhythm makes the world go round: An MEG-TMS study on the role of right TPJ theta oscillations in embodied perspective taking},

author = {Hongfang Wang and Eleanor Callaghan and Gerard Gooding-Williams and Craig McAllister and Klaus Kessler},

doi = {10.1016/j.cortex.2015.11.011},

year  = {2016},

date = {2016-01-01},

journal = {Cortex},

volume = {75},

pages = {68–81},

publisher = {Elsevier Ltd},

abstract = {While some aspects of social processing are shared between humans and other species, some aspects are not. The former seems to apply to merely tracking another's visual perspective in the world (i.e., what a conspecific can or cannot perceive), while the latter applies to perspective taking in form of mentally "embodying" another's viewpoint. Our previous behavioural research had indicated that only perspective taking, but not tracking, relies on simulating a body schema rotation into another's viewpoint. In the current study we employed Magnetoencephalography (MEG) and revealed that this mechanism of mental body schema rotation is primarily linked to theta oscillations in a wider brain network of body-schema, somatosensory and motor-related areas, with the right posterior temporo-parietal junction (pTPJ) at its core. The latter was reflected by a convergence of theta oscillatory power in right pTPJ obtained by overlapping the separately localised effects of rotation demands (angular disparity effect), cognitive embodiment (posture congruence effect), and basic body schema involvement (posture relevance effect) during perspective taking in contrast to perspective tracking. In a subsequent experiment we interfered with right pTPJ processing using dual pulse Transcranial Magnetic Stimulation (dpTMS) and observed a significant reduction of embodied processing. We conclude that right TPJ is the crucial network hub for transforming the embodied self into another's viewpoint, body and/or mind, thus, substantiating how conflicting representations between self and other may be resolved and potentially highlighting the embodied origins of high-level social cognition in general.},

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@article{Adams2016,

title = {Dynamic causal modelling of eye movements during pursuit: Confirming precision-encoding in V1 using MEG},

author = {Rick A. Adams and Markus Bauer and Dimitris Pinotsis and Karl J. Friston},

doi = {10.1016/j.neuroimage.2016.02.055},

year  = {2016},

date = {2016-01-01},

journal = {Neuroimage},

volume = {132},

pages = {175–189},

publisher = {The Authors},

abstract = {This paper shows that it is possible to estimate the subjective precision (inverse variance) of Bayesian beliefs during oculomotor pursuit. Subjects viewed a sinusoidal target, with or without random fluctuations in its motion. Eye trajectories and magnetoencephalographic (MEG) data were recorded concurrently. The target was periodically occluded, such that its reappearance caused a visual evoked response field (ERF). Dynamic causal modelling (DCM) was used to fit models of eye trajectories and the ERFs. The DCM for pursuit was based on predictive coding and active inference, and predicts subjects' eye movements based on their (subjective) Bayesian beliefs about target (and eye) motion. The precisions of these hierarchical beliefs can be inferred from behavioural (pursuit) data. The DCM for MEG data used an established biophysical model of neuronal activity that includes parameters for the gain of superficial pyramidal cells, which is thought to encode precision at the neuronal level. Previous studies (using DCM of pursuit data) suggest that noisy target motion increases subjective precision at the sensory level: i.e., subjects attend more to the target's sensory attributes. We compared (noisy motion-induced) changes in the synaptic gain based on the modelling of MEG data to changes in subjective precision estimated using the pursuit data. We demonstrate that imprecise target motion increases the gain of superficial pyramidal cells in V1 (across subjects). Furthermore, increases in sensory precision – inferred by our behavioural DCM – correlate with the increase in gain in V1, across subjects. This is a step towards a fully integrated model of brain computations, cortical responses and behaviour that may provide a useful clinical tool in conditions like schizophrenia.},

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@article{Allen2016,

title = {Unexpected arousal modulates the influence of sensory noise on confidence},

author = {Micah Allen and Darya Frank and D. Samuel Schwarzkopf and Francesca Fardo and Joel S. Winston and Tobias U. Hauser and Geraint Rees},

doi = {10.7554/eLife.18103},

year  = {2016},

date = {2016-01-01},

journal = {eLife},

volume = {5},

pages = {1–17},

abstract = {Human perception is invariably accompanied by a graded feeling of confidence that guides metacognitive awareness and decision-making. It is often assumed that this arises solely from the feed-forward encoding of the strength or precision of sensory inputs. In contrast, interoceptive inference models suggest that confidence reflects a weighted integration of sensory precision and expectations about internal states, such as arousal. Here we test this hypothesis using a novel psychophysical paradigm, in which unseen disgust-cues induced unexpected, unconscious arousal just before participants discriminated motion signals of variable precision. Across measures of perceptual bias, uncertainty, and physiological arousal we found that arousing disgust cues modulated the encoding of sensory noise. Furthermore, the degree to which trial-by-trial pupil fluctuations encoded this nonlinear interaction correlated with trial level confidence. Our results suggest that unexpected arousal regulates perceptual precision, such that subjective confidence reflects the integration of both external sensory and internal, embodied states.},

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@article{BaboRebelo2016,

title = {Neural responses to heartbeats in the default network encode the self in spontaneous thoughts},

author = {Mariana Babo-Rebelo and Craig G. Richter and Catherine Tallon-Baudry},

doi = {10.1523/JNEUROSCI.0262-16.2016},

year  = {2016},

date = {2016-01-01},

journal = {Journal of Neuroscience},

volume = {36},

number = {30},

pages = {7829–7840},

abstract = {The default network (DN) has been consistently associated with self-related cognition, but also to bodily state monitoring and autonomic regulation. We hypothesized that these two seemingly disparate functional roles of the DN are functionally coupled, in line with theories proposing that selfhood is grounded in the neural monitoring of internal organs, such as the heart. We measured with magnetoencephalograhy neural responses evoked by heartbeats while human participants freely mind-wandered. When interrupted by a visual stimulus at random intervals, participants scored the self-relatedness of the interrupted thought. They evaluated their involvement as the first-person perspective subject or agent in the thought ("I"), and on another scale to what degree they were thinking about themselves ("Me"). During the interrupted thought, neural responses to heartbeats in two regions of the DN, the ventral precuneus and the ventromedial prefrontal cortex, covaried, respectively, with the "I" and the "Me" dimensions of the self, even at the single-trial level. No covariation between self-relatedness and peripheral autonomic measures (heart rate, heart rate variability, pupil diameter, electrodermal activity, respiration rate, and phase) or alpha power was observed. Our results reveal a direct link between selfhood and neural responses to heartbeats in the DN and thus directly support theories grounding selfhood in the neural monitoring of visceral inputs. More generally, the tight functional coupling between self-related processing and cardiac monitoring observed here implies that, even in the absence of measured changes in peripheral bodily measures, physiological and cognitive functions have to be considered jointly in the DN.},

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@article{LopezPerez2016,

title = {Semantic parafoveal-on-foveal effects and preview benefits in reading: Evidence from fixation related potentials},

author = {P. J. López-Peréz and J. Dampuré and J. A. Hernández-Cabrera and H. A. Barber},

doi = {10.1016/j.bandl.2016.07.009},

year  = {2016},

date = {2016-01-01},

journal = {Brain and Language},

volume = {162},

pages = {29–34},

abstract = {During reading parafoveal information can affect the processing of the word currently fixated (parafovea-on-fovea effect) and words perceived parafoveally can facilitate their subsequent processing when they are fixated on (preview effect). We investigated parafoveal processing by simultaneously recording eye movements and EEG measures. Participants read word pairs that could be semantically associated or not. Additionally, the boundary paradigm allowed us to carry out the same manipulation on parafoveal previews that were displayed until reader's gaze moved to the target words. Event Related Potentials time-locked to the prime-preview presentation showed a parafoveal-on-foveal N400 effect. Fixation Related Potentials time locked to the saccade offset showed an N400 effect related to the prime-target relationship. Furthermore, this later effect interacted with the semantic manipulation of the previews, supporting a semantic preview benefit. These results demonstrate that at least under optimal conditions foveal and parafoveal information can be simultaneously processed and integrated.},

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}

@article{Manor2016,

title = {Multimodal neural network for rapid serial visual presentation brain computer interface},

author = {Ran Manor and Liran Mishali and Amir B. Geva},

doi = {10.3389/fncom.2016.00130},

year  = {2016},

date = {2016-01-01},

journal = {Frontiers in Computational Neuroscience},

volume = {10},

pages = {130},

abstract = {Brain computer interfaces allow users to preform various tasks using only the electrical activity of the brain. BCI applications often present the user a set of stimuli and record the corresponding electrical response. The BCI algorithm will then have to decode the acquired brain response and perform the desired task. In rapid serial visual presentation (RSVP) tasks, the subject is presented with a continuous stream of images containing rare target images among standard images, while the algorithm has to detect brain activity associated with target images. In this work, we suggest a multimodal neural network for RSVP tasks. The network operates on the brain response and on the initiating stimulus simultaneously, providing more information for the BCI application. We present two variants of the multimodal network, a supervised model, for the case when the targets are known in advanced, and a semi-supervised model for when the targets are unknown. We test the neural networks with a RSVP experiment on satellite imagery carried out with two subjects. The multimodal networks achieve a significant performance improvement in classification metrics. We visualize what the networks has learned and discuss the advantages of using neural network models for BCI applications.},

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@article{Marshall2016,

title = {On the relationship between cortical excitability and visual oscillatory responses-A concurrent tDCS-MEG study},

author = {Tom R. Marshall and Sophie Esterer and Jim D. Herring and Til O. Bergmann and Ole Jensen},

doi = {10.1016/j.neuroimage.2015.09.069},

year  = {2016},

date = {2016-01-01},

journal = {NeuroImage},

volume = {140},

pages = {41–49},

publisher = {Elsevier Inc.},

abstract = {Neuronal oscillations in the alpha band (8–12 Hz) in visual cortex are considered to instantiate ‘attentional gating' via the inhibition of activity in regions representing task-irrelevant parts of space. In contrast, visual gamma-band activity (40–100 Hz) is regarded as representing a bottom-up drive from incoming visual information, with increased synchronisation producing a stronger feedforward impulse for relevant information. However, little is known about the direct relationship between excitability of the visual cortex and these oscillatory mechanisms. In this study we used transcranial direct current stimulation (tDCS) in an Oz–Cz montage in order to stimulate visual cortex, concurrently recording whole-brain oscillatory activity using magnetoencephalography (MEG) whilst participants performed a visual task known to produce strong modulations of alpha- and gamma-band activity. We found that visual stimuli produced expected modulations of alpha and gamma – presenting a moving annulus stimulus led to a strong gamma increase and alpha decrease – and that this pattern was observable both during active (anodal and cathodal) tDCS and sham tDCS. However, tDCS did not seem to produce systematic alterations of these oscillatory responses. The present study thus demonstrates that concurrent tDCS/MEG of the visual system is a feasible tool for investigating visual neuronal oscillations, and we discuss potential reasons for the apparent inability of tDCS to effectively change the amplitude of visual stimulus induced oscillatory responses in the current study.},

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@article{McMahon2016,

title = {Monitoring alpha oscillations and pupil dilation across a performance-intensity function},

author = {Catherine M. McMahon and Isabelle Boisvert and Peter Lissa and Louise Granger and Ronny Ibrahim and Chi Yhun Lo and Kelly Miles and Petra L. Graham},

doi = {10.3389/fpsyg.2016.00745},

year  = {2016},

date = {2016-01-01},

journal = {Frontiers in Psychology},

volume = {7},

pages = {745},

abstract = {Listening to degraded speech can be challenging and requires a continuous investment of cognitive resources, which is more challenging for those with hearing loss. However, while alpha power (8-12 Hz) and pupil dilation have been suggested as objective correlates of listening effort, it is not clear whether they assess the same cognitive processes involved, or other sensory and/or neurophysiological mechanisms that are associated with the task. Therefore, the aim of this study is to compare alpha power and pupil dilation during a sentence recognition task in 15 randomized levels of noise (-7dB to +7dB SNR) using highly intelligible (16 channel vocoded) and moderately intelligible (6 channel vocoded) speech. Twenty young normal hearing adults participated in the study; however, due to extraneous noise, data from 16 (10 females, 6 males; aged 19-28 years) was used in the EEG analysis and 10 in the pupil analysis. Behavioral testing of perceived effort and speech performance was assessed at 3 fixed SNRs per participant and was comparable to sentence recognition performance assessed in the physiological test session for both 16- and 6-channel vocoded sentences. Results showed a significant interaction between channel vocoding for both the alpha power and the pupil size changes. While both measures significantly decreased with more positive SNRs for the 16-channel vocoding, this was not observed with the 6-channel vocoding. The results of this study suggest that these measures may encode different processes involved in speech perception, which show similar trends for highly intelligible speech, but diverge for more spectrally degraded speech. The results to date suggest that these objective correlates of listening effort, and the cognitive processes involved in listening effort, are not yet sufficiently well understood to be used within a clinical setting.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Mitchell2016,

title = {Recognition of faces and names: Multimodal physiological correlates of memory and executive function},

author = {Meghan B. Mitchell and Steven D. Shirk and Donald G. McLaren and Jessica S. Dodd and Ali Ezzati and Brandon A. Ally and Alireza Atri},

doi = {10.1007/s11682-015-9420-6},

year  = {2016},

date = {2016-01-01},

journal = {Brain Imaging and Behavior},

volume = {10},

number = {2},

pages = {408–423},

publisher = {Brain Imaging and Behavior},

abstract = {We sought to characterize electrophysiological, eye-tracking and behavioral correlates of face-name recognition memory in healthy younger adults using high-density electroencephalography (EEG), infrared eye-tracking (ET), and neuropsychological measures. Twenty-one participants first studied 40 face-name (FN) pairs; 20 were presented four times (4R) and 20 were shown once (1R). Recognition memory was assessed by asking participants to make old/new judgments for 80 FN pairs, of which half were previously studied items and half were novel FN pairs (N). Simultaneous EEG and ET recording were collected during recognition trials. Comparisons of event-related potentials (ERPs) for correctly identified FN pairs were compared across the three item types revealing classic ERP old/new effects including 1) relative positivity (1R > N) bi-frontally from 300 to 500 ms, reflecting enhanced familiarity, 2) relative positivity (4R > 1R and 4R > N) in parietal areas from 500 to 800 ms, reflecting enhanced recollection, and 3) late frontal effects (1R > N) from 1000 to 1800 ms in right frontal areas, reflecting post-retrieval monitoring. ET analysis also revealed significant differences in eye movements across conditions. Exploration of cross-modality relationships suggested associations between memory and executive function measures and the three ERP effects. Executive function measures were associated with several indicators of saccadic eye movements and fixations, which were also associated with all three ERP effects. This novel characterization of face-name recognition memory performance using simultaneous EEG and ET reproduced classic ERP and ET effects, supports the construct validity of the multimodal FN paradigm, and holds promise as an integrative tool to probe brain networks supporting memory and executive functioning.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Mok2016,

title = {Behavioral and neural markers of flexible attention over working memory in aging},

author = {Robert M. Mok and Nicholas E. Myers and George Wallis and Anna C. Nobre},

doi = {10.1093/cercor/bhw011},

year  = {2016},

date = {2016-01-01},

journal = {Cerebral Cortex},

volume = {26},

number = {4},

pages = {1831–1842},

abstract = {Working memory (WM) declines as we age and, because of its fundamental role in higher order cognition, this can have highly deleterious effects in daily life. We investigated whether older individuals benefit from flexible orienting of attention within WM to mitigate cognitive decline. We measured magnetoencephalography (MEG) in older adults performing a WM precision task with cues during the maintenance period that retroactively predicted the location of the relevant items for performance (retro-cues). WM performance of older adults significantly benefitted from retro-cues. Whereas WM maintenance declined with age, retro-cues conferred strong attentional benefits. A model-based analysis revealed an increase in the probability of recalling the target, a lowered probability of retrieving incorrect items or guessing, and an improvement in memory precision. MEG recordings showed that retro-cues induced a transient lateralization of alpha (8-14 Hz) and beta (15-30 Hz) oscillatory power. Interestingly, shorter durations of alpha/beta lateralization following retro-cues predicted larger cueing benefits, reinforcing recent ideas about the dynamic nature of access to WM representations. Our results suggest that older adults retain flexible control over WM, but individual differences in control correspond to differences in neural dynamics, possibly reflecting the degree of preservation of control in healthy aging.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Mueller2016b,

title = {Comparing eye tracking with electrooculography for measuring individual sentence comprehension duration},

author = {Jana Annina Müller and Dorothea Wendt and Birger Kollmeier and Thomas Brand},

doi = {10.1371/journal.pone.0164627},

year  = {2016},

date = {2016-01-01},

journal = {PLoS ONE},

volume = {11},

number = {10},

pages = {e0164627},

abstract = {The aim of this study was to validate a procedure for performing the audio-visual paradigm introduced by Wendt et al. (2015) with reduced practical challenges. The original paradigm records eye fixations using an eye tracker and calculates the duration of sentence comprehension based on a bootstrap procedure. In order to reduce practical challenges, we first reduced the measurement time by evaluating a smaller measurement set with fewer trials. The results of 16 listeners showed effects comparable to those obtained when testing the original full measurement set on a different collective of listeners. Secondly, we introduced electrooculography as an alternative technique for recording eye movements. The correlation between the results of the two recording techniques (eye tracker and electrooculography) was r = 0.97, indicating that both methods are suitable for estimating the processing duration of individual participants. Similar changes in processing duration arising from sentence complexity were found using the eye tracker and the electrooculography procedure. Thirdly, the time course of eye fixations was estimated with an alternative procedure, growth curve analysis, which is more commonly used in recent studies analyzing eye tracking data. The results of the growth curve analysis were compared with the results of the bootstrap procedure. Both analysis methods show similar processing durations.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Godier2016,

title = {Enhanced early neuronal processing of food pictures in Anorexia Nervosa: A magnetoencephalography study},

author = {Lauren R. Godier and Jessica C. Scaife and Sven Braeutigam and Rebecca J. Park},

doi = {10.1155/2016/1795901},

year  = {2016},

date = {2016-01-01},

journal = {Psychiatry Journal},

volume = {2016},

pages = {1–13},

abstract = {Neuroimaging studies in Anorexia Nervosa (AN) have shown increased activation in reward and cognitive control regions in response to food, and a behavioral attentional bias (AB) towards food stimuli is reported. This study aimed to further investigate the neural processing of food using magnetoencephalography (MEG). Participants were 13 females with restricting-type AN, 14 females recovered from restricting-type AN, and 15 female healthy controls. MEG data was acquired whilst participants viewed high- and low-calorie food pictures. Attention was assessed with a reaction time task and eye tracking. Time-series analysis suggested increased neural activity in response to both calorie conditions in the AN groups, consistent with an early AB. Increased activity was observed at 150 ms in the current AN group. Neuronal activity at this latency was at normal level in the recovered group; however, this group exhibited enhanced activity at 320 ms after stimulus. Consistent with previous studies, analysis in source space and behavioral data suggested enhanced attention and cognitive control processes in response to food stimuli in AN. This may enable avoidance of salient food stimuli and maintenance of dietary restraint in AN. A later latency of increased activity in the recovered group may reflect a reversal of this avoidance, with source space and behavioral data indicating increased visual and cognitive processing of food stimuli.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Golan2016,

title = {Human intracranial recordings link suppressed transients rather than 'filling-in' to perceptual continuity across blinks},

author = {Tal Golan and Ido Davidesco and Meir Meshulam and David M. Groppe and Pierre Mégevand and Erin M. Yeagle and Matthew S. Goldfinger and Michal Harel and Lucia Melloni and Charles E. Schroeder and D. L. Deouell and Ashesh D. Mehta and Rafael Malach},

doi = {10.7554/eLife.17243},

year  = {2016},

date = {2016-01-01},

journal = {eLife},

volume = {5},

pages = {1–28},

abstract = {We hardly notice our eye blinks, yet an externally generated retinal interruption of a similar duration is perceptually salient. We examined the neural correlates of this perceptual distinction using intracranially measured ECoG signals from human visual cortex in 14 patients. In early visual areas (V1 and V2), the disappearance of the stimulus due to either invisible blinks or salient blank video frames ('gaps') led to a similar drop in activity level, followed by a positive overshoot beyond baseline, triggered by stimulus reappearance. Ascending the visual hierarchy, the reappearance-related overshoot gradually subsided for blinks but not for gaps. By contrast, the disappearance-related drop did not follow the perceptual distinction - it was actually slightly more pronounced for blinks than for gaps. These findings suggest that blinks' limited visibility compared with gaps is correlated with suppression of blink-related visual activity transients, rather than with 'filling-in' of the occluded content during blinks.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{GonenYaacovi2016,

title = {Increased ongoing neural variability in ADHD},

author = {Gil Gonen-Yaacovi and Ayelet Arazi and Nitzan Shahar and Anat Karmon and Shlomi Haar and Nachshon Meiran and Ilan Dinstein},

doi = {10.1016/j.cortex.2016.04.010},

year  = {2016},

date = {2016-01-01},

journal = {Cortex},

volume = {81},

pages = {50–63},

publisher = {Elsevier Ltd},

abstract = {Attention Deficit Hyperactivity Disorder (ADHD) has been described as a disorder where frequent lapses of attention impair the ability of an individual to focus/attend in a sustained manner, thereby generating abnormally large intra-individual behavioral variability across trials. Indeed, increased reaction time (RT) variability is a fundamental behavioral characteristic of individuals with ADHD found across a large number of cognitive tasks. But what is the underlying neurophysiology that might generate such behavioral instability? Here, we examined trial-by-trial EEG response variability to visual and auditory stimuli while subjects' attention was diverted to an unrelated task at the fixation cross. Comparisons between adult ADHD and control participants revealed that neural response variability was significantly larger in the ADHD group as compared with the control group in both sensory modalities. Importantly, larger trial-by-trial variability in ADHD was apparent before and after stimulus presentation as well as in trials where the stimulus was omitted, suggesting that ongoing (rather than stimulus-evoked) neural activity is continuously more variable (noisier) in ADHD. While the patho-physiological mechanisms causing this increased neural variability remain unknown, they appear to act continuously rather than being tied to a specific sensory or cognitive process.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Gregory2016a,

title = {Gamma frequency and the spatial tuning of primary visual cortex},

author = {Sarah Gregory and Marco Fusca and Geraint Rees and D. Samuel Schwarzkopf and Gareth Barnes},

doi = {10.1371/journal.pone.0157374},

year  = {2016},

date = {2016-01-01},

journal = {PLoS ONE},

volume = {11},

number = {6},

pages = {e0157374},

abstract = {Visual stimulation produces oscillatory gamma responses in human primary visual cortex (V1) that also relate to visual perception. We have shown previously that peak gamma frequency positively correlates with central V1 cortical surface area. We hypothesized that people with larger V1 would have smaller receptive fields and that receptive field size, not V1 are, might explain this relationship. Here we set out to test this hypothesis directly by investigating the relationship between fMRI estimated population receptive field (pRF) size and gamma frequency in V1. We stimulated both the near-centre and periphery of the visual field using both large and small stimuli in each location and replicated our previous finding of a positive correlation between V1 surface area and peak gamma frequency. Counter to our expectation, we found that between participants V1 size (and not pRF size) accounted for most of the variability in gamma frequency. Within-participants we found that gamma frequency increased, rather than decreased, with stimulus eccentricity directly contradicting our initial hypothesis.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Gutteling2016,

title = {Role of alpha-band oscillations in spatial updating across whole body motion},

author = {Tjerk P. Gutteling and W. Pieter Medendorp},

doi = {10.3389/fpsyg.2016.00671},

year  = {2016},

date = {2016-01-01},

journal = {Frontiers in Psychology},

volume = {7},

pages = {671},

abstract = {When moving around in the world, we have to keep track of important locations in our surroundings. In this process, called spatial updating, we must estimate our body motion and correct representations of memorized spatial locations in accordance with this motion. While the behavioral characteristics of spatial updating across whole body motion have been studied in detail, its neural implementation lacks detailed study. Here we use electro-encephalography (EEG) to distinguish various spectral components of this process. Subjects gazed at a central body-fixed point in otherwise complete darkness, while a target was briefly flashed, either left or right from this point. Subjects had to remember the location of this target as either moving along with the body or remaining fixed in the world while being translated sideways on a passive motion platform. After the motion, subjects had to indicate the remembered target location in the instructed reference frame using a mouse response. While the body motion, as detected by the vestibular system, should not affect the representation of body-fixed targets, it should interact with the representation of a world-centered target to update its location relative to the body. We show that the initial presentation of the visual target induced a reduction of alpha band power in contralateral parieto-occipital areas, which evolved to a sustained increase during the subsequent memory period. Motion of the body led to a reduction of alpha band power in central parietal areas extending to lateral parieto-temporal areas, irrespective of whether the targets had to be memorized relative to world or body. When updating a world-fixed target, its internal representation shifts hemispheres, only when subjects' behavioral responses suggested an update across the body midline. Our results suggest that parietal cortex is involved in both self-motion estimation and the selective application of this motion information to maintaining target locations as fixed in the world or fixed to the body.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Heidlmayr2016,

title = {Multiple language use influences oculomotor task performance: Neurophysiological evidence of a shared substrate between language and motor control},

author = {Karin Heidlmayr and Karine Dore-Mazars and Xavier Aparico and Frederic Isel},

doi = {10.1371/journal.pone.0165029},

year  = {2016},

date = {2016-01-01},

journal = {PLoS ONE},

volume = {11},

number = {11},

pages = {e0165029},

abstract = {In the present electroencephalographical study, we asked to which extent executive control processes are shared by both the language and motor domain. The rationale was to examine whether executive control processes whose efficiency is reinforced by the frequent use of a second language can lead to a benefit in the control of eye movements, i.e. a non-linguistic activity. For this purpose, we administrated to 19 highly proficient late French-German bilingual participants and to a control group of 20 French monolingual participants an antisaccade task, i.e. a specific motor task involving control. In this task, an automatic saccade has to be suppressed while a voluntary eye movement in the opposite direction has to be carried out. Here, our main hypothesis is that an advantage in the antisaccade task should be observed in the bilinguals if some properties of the control processes are shared between linguistic and motor domains. ERP data revealed clear differences between bilinguals and monolinguals. Critically, we showed an increased N2 effect size in bilinguals, thought to reflect better efficiency to monitor conflict, combined with reduced effect sizes on markers reflecting inhibitory control, i.e. cue-locked positivity, the target-locked P3 and the saccade-locked presaccadic positivity (PSP). Moreover, effective connectivity analyses (dynamic causal modelling; DCM) on the neuronal source level indicated that bilinguals rely more strongly on ACC-driven control while monolinguals rely on PFC-driven control. Taken together, our combined ERP and effective connectivity findings may reflect a dynamic interplay between strengthened conflict monitoring, associated with subsequently more efficient inhibition in bilinguals. Finally, L2 proficiency and immersion experience constitute relevant factors of the language background that predict efficiency of inhibition. To conclude, the present study provided ERP and effective connectivity evidence for domain-general executive control involvement in handling multiple language use, leading to a control advantage in bilingualism.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{HuberHuber2016,

title = {Using temporally aligned event-related potentials for the investigation of attention shifts prior to and during saccades},

author = {Christoph Huber-Huber and Thomas Ditye and María Marchante Fernández and Ulrich Ansorge},

doi = {10.1016/j.neuropsychologia.2016.03.035},

year  = {2016},

date = {2016-01-01},

journal = {Neuropsychologia},

volume = {92},

pages = {129–141},

publisher = {Elsevier},

abstract = {According to the pre-motor theory of attention, attention is shifted to a saccade's landing position before the saccade is executed. Such pre-saccadic attention shifts are usually studied in psychophysical dual-task conditions, with a target-discrimination task before saccade onset. Here, we present a novel approach to investigate pre-saccadic attention shifts with the help of event-related potentials (ERPs). Participants executed one or two saccades to color-defined targets while ERPs and eye-movements were recorded. In single-target blocks participants executed a single saccade. In two-targets blocks participants made either a single saccade to one of the targets, or two successive saccades to both targets. Importantly, in two-targets blocks, targets could appear on the same or on opposite sides of the vertical midline. This allowed us to study contra-to-ipsilateral ERP differences (such as the N2pc or PCN) that reflect attention shifts to the targets, prior to saccade onset and during saccades. If pre-saccadic attention shifts to saccade target locations are necessary for saccade execution and if searched-for saccade targets capture attention, there should be enhanced attentional competition (1) between two targets compared to single targets; (2) between two opposite-sides targets compared to two same-side targets; and (3) in two saccades rather than one saccade conditions: More attentional competition was expected to delay saccade latency and to weaken pre-saccadic laterality effects in ERPs. Hypotheses were tested by means of temporally aligned ERPs that were simultaneously time-locked to stimulus onsets, saccade onsets, and saccade offsets. Predictions (1) and (2) were partly and fully confirmed, respectively, but no evidence was found for (3). We explain the implications of our results for the role of attention during saccade preparation, and we point out how temporally aligned ERPs compare to ICA-based electroencephalogram (EEG) artifact correction procedures and to psychophysical dual-task approaches.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Ikkai2016,

title = {Lateralization in alpha-band oscillations predicts the locus and spatial distribution of attention},

author = {Akiko Ikkai and Sangita Dandekar and Clayton E. Curtis},

doi = {10.1371/journal.pone.0154796},

year  = {2016},

date = {2016-01-01},

journal = {PLoS ONE},

volume = {11},

number = {5},

pages = {e0154796},

abstract = {Attending to a task-relevant location changes how neural activity oscillates in the alpha band (8-13Hz) in posterior visual cortical areas. However, a clear understanding of the relationships between top-down attention, changes in alpha oscillations in visual cortex, and attention performance are still poorly understood. Here, we tested the degree to which the posterior alpha power tracked the locus of attention, the distribution of attention, and how well the topography of alpha could predict the locus of attention. We recorded magnetoencephalographic (MEG) data while subjects performed an attention demanding visual discrimination task that dissociated the direction of attention from the direction of a saccade to indicate choice. On some trials, an endogenous cue predicted the target's location, while on others it contained no spatial information. When the target's location was cued, alpha power decreased in sensors over occipital cortex contralateral to the attended visual field. When the cue did not predict the target's location, alpha power again decreased in sensors over occipital cortex, but bilaterally, and increased in sensors over frontal cortex. Thus, the distribution and the topography of alpha reliably indicated the locus of covert attention. Together, these results suggest that alpha synchronization reflects changes in the excitability of populations of neurons whose receptive fields match the locus of attention. This is consistent with the hypothesis that alpha oscillations reflect the neural mechanisms by which top-down control of attention biases information processing and modulate the activity of neurons in visual cortex.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{NaeemMannan2016,

title = {Hybrid EEG—Eye tracker: Automatic identification and removal of eye movement and blink artifacts from electroencephalographic signal},

author = {Malik M. Naeem Mannan and Shinjung Kim and Myung Yung Jeong and M. Ahmad Kamran},

doi = {10.3390/s16020241},

year  = {2016},

date = {2016-01-01},

journal = {Sensors},

volume = {16},

pages = {241},

abstract = {Contamination of eye movement and blink artifacts in Electroencephalogram (EEG) recording makes the analysis of EEG data more difficult and could result in mislead findings. Efficient removal of these artifacts from EEG data is an essential step in improving classification accuracy to develop the brain-computer interface (BCI). In this paper, we proposed an automatic framework based on independent component analysis (ICA) and system identification to identify and remove ocular artifacts from EEG data by using hybrid EEG and eye tracker system. The performance of the proposed algorithm is illustrated using experimental and standard EEG datasets. The proposed algorithm not only removes the ocular artifacts from artifactual zone but also preserves the neuronal activity related EEG signals in non-artifactual zone. The comparison with the two state-of-the-art techniques namely ADJUST based ICA and REGICA reveals the significant improved performance of the proposed algorithm for removing eye movement and blink artifacts from EEG data. Additionally, results demonstrate that the proposed algorithm can achieve lower relative error and higher mutual information values between corrected EEG and artifact-free EEG data.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Namazi2016,

title = {The analysis of the influence of fractal structure of stimuli on fractal dynamics in fixational eye movements and EEG signal},

author = {Hamidreza Namazi and Vladimir V. Kulish and Amin Akrami},

doi = {10.1038/srep26639},

year  = {2016},

date = {2016-01-01},

journal = {Scientific Reports},

volume = {6},

pages = {26639},

publisher = {Nature Publishing Group},

abstract = {One of the major challenges in vision research is to analyze the effect of visual stimuli on human vision. However, no relationship has been yet discovered between the structure of the visual stimulus, and the structure of fixational eye movements. This study reveals the plasticity of human fixational eye movements in relation to the ‘complex' visual stimulus. We demonstrated that the fractal temporal structure of visual dynamics shifts towards the fractal dynamics of the visual stimulus (image). The results showed that images with higher complexity (higher fractality) cause fixational eye movements with lower fractality. Considering the brain, as the main part of nervous system that is engaged in eye movements, we analyzed the governed Electroencephalogram (EEG) signal during fixation. We have found out that there is a coupling between fractality of image, EEG and fixational eye movements. The capability observed in this research can be further investigated and applied for treatment of different vision disorders.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{NeathTavares2016,

title = {Neural processing of fearful and happy facial expressions during emotion-relevant and emotion-irrelevant tasks: A fixation-to-feature approach},

author = {Karly N. Neath-Tavares and Roxane J. Itier},

doi = {10.1016/j.biopsycho.2016.07.013},

year  = {2016},

date = {2016-01-01},

journal = {Biological Psychology},

volume = {119},

pages = {122–140},

publisher = {Elsevier B.V.},

abstract = {Research suggests an important role of the eyes and mouth for discriminating facial expressions of emotion. A gaze-contingent procedure was used to test the impact of fixation to facial features on the neural response to fearful, happy and neutral facial expressions in an emotion discrimination (Exp.1) and an oddball detection (Exp.2) task. The N170 was the only eye-sensitive ERP component, and this sensitivity did not vary across facial expressions. In both tasks, compared to neutral faces, responses to happy expressions were seen as early as 100–120 ms occipitally, while responses to fearful expressions started around 150 ms, on or after the N170, at both occipital and lateral-posterior sites. Analyses of scalp topographies revealed different distributions of these two emotion effects across most of the epoch. Emotion processing interacted with fixation location at different times between tasks. Results suggest a role of both the eyes and mouth in the neural processing of fearful expressions and of the mouth in the processing of happy expressions, before 350 ms.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Nikolaev2016,

title = {Combining EEG and eye movement recording in free viewing: Pitfalls and possibilities},

author = {Andrey R. Nikolaev and Radha Nila Meghanathan and Cees Leeuwen},

doi = {10.1016/j.bandc.2016.06.004},

year  = {2016},

date = {2016-01-01},

journal = {Brain and Cognition},

volume = {107},

pages = {55–83},

publisher = {Elsevier Inc.},

abstract = {Co-registration of EEG and eye movement has promise for investigating perceptual processes in free viewing conditions, provided certain methodological challenges can be addressed. Most of these arise from the self-paced character of eye movements in free viewing conditions. Successive eye movements occur within short time intervals. Their evoked activity is likely to distort the EEG signal during fixation. Due to the non-uniform distribution of fixation durations, these distortions are systematic, survive across-trials averaging, and can become a source of confounding. We illustrate this problem with effects of sequential eye movements on the evoked potentials and time-frequency components of EEG and propose a solution based on matching of eye movement characteristics between experimental conditions. The proposal leads to a discussion of which eye movement characteristics are to be matched, depending on the EEG activity of interest. We also compare segmentation of EEG into saccade-related epochs relative to saccade and fixation onsets and discuss the problem of baseline selection and its solution. Further recommendations are given for implementing EEG-eye movement co-registration in free viewing conditions. By resolving some of the methodological problems involved, we aim to facilitate the transition from the traditional stimulus-response paradigm to the study of visual perception in more naturalistic conditions.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Ohl2016,

title = {Revealing the time course of signals influencing the generation of secondary saccades using Aalen's additive hazards model},

author = {Sven Ohl and Reinhold Kliegl},

doi = {10.1016/j.visres.2016.06.007},

year  = {2016},

date = {2016-01-01},

journal = {Vision Research},

volume = {124},

pages = {52–58},

abstract = {Saccadic eye movements are frequently followed by smaller secondary saccades which are generally assumed to correct for the error in primary saccade landing position. However, secondary saccades can also occur after accurate primary saccades and they are often as small as microsaccades, therefore raising the need to further scrutinize the processes involved in secondary saccade generation. Following up a previous study, we analyzed secondary saccades using rate analysis which allows us to quantify experimental effects as shifts in distributions, therefore going beyond comparisons of mean differences. We use Aalen's additive hazards model to delineate the time course of key influences on the secondary saccade rate. In addition to the established effect of primary saccade error, we observed a time-varying influence of under- vs. overshooting - with a higher risk of generating secondary saccades following undershoots. Moreover, increasing target eccentricity influenced the programming of secondary saccades, therefore demonstrating that error-unrelated variables co-determine secondary saccade programs. Our results provide new insights into the generative mechanisms of small saccades during postsaccadic fixation that need to be accounted for by secondary saccade models.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Ohl2016a,

title = {Microsaccades are coupled to heartbeat},

author = {Sven Ohl and Christian Wohltat and Reinhold Kliegl and Olga Pollatos and Ralf Engbert},

doi = {10.1523/JNEUROSCI.2211-15.2016},

year  = {2016},

date = {2016-01-01},

journal = {Journal of Neuroscience},

volume = {36},

number = {4},

pages = {1237–1241},

abstract = {During visual fixation, the eye generates microsaccades and slower components of fixational eye movements that are part of the visual processing strategy in humans. Here, we show that ongoing heartbeat is coupled to temporal rate variations in the generation of microsaccades. Using coregistration of eye recording and ECG in humans, we tested the hypothesis that microsaccade onsets are coupled to the relative phase of the R-R intervals in heartbeats. We observed significantly more microsaccades during the early phase after the R peak in the ECG. This form of coupling between heartbeat and eye movements was substantiated by the additional finding of a coupling between heart phase and motion activity in slow fixational eye movements; i.e., retinal image slip caused by physiological drift. Our findings therefore demonstrate a coupling of the oculomotor system and ongoing heartbeat, which provides further evidence for bodily influences on visuomotor functioning.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Pape2016,

title = {Motor cortex activity predicts response alternation during sensorimotor decisions},

author = {Anna Antonia Pape and Markus Siegel},

doi = {10.1038/ncomms13098},

year  = {2016},

date = {2016-01-01},

journal = {Nature Communications},

volume = {7},

pages = {13098},

publisher = {Nature Publishing Group},

abstract = {Our actions are constantly guided by decisions based on sensory information. The motor cortex is traditionally viewed as the final output stage in this process, merely executing motor responses based on these decisions. However, it is not clear if, beyond this role, the motor cortex itself impacts response selection. Here, we report activity fluctuations over motor cortex measured using MEG, which are unrelated to choice content and predict responses to a visuomotor task seconds before decisions are made. These fluctuations are strongly influenced by the previous trial's response and predict a tendency to switch between response alternatives for consecutive decisions. This alternation behaviour depends on the size of neural signals still present from the previous response. Our results uncover a response-alternation bias in sensorimotor decision making. Furthermore, they suggest that motor cortex is more than an output stage and instead shapes response selection during sensorimotor decision making.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Park2016,

title = {Lip movements entrain the observers' low-frequency brain oscillations to facilitate speech intelligibility},

author = {Hyojin Park and Christoph Kayser and Gregor Thut and Joachim Gross},

doi = {10.7554/eLife.14521},

year  = {2016},

date = {2016-01-01},

journal = {eLife},

volume = {5},

pages = {1–17},

abstract = {During continuous speech, lip movements provide visual temporal signals that facilitate speech processing. Here, using MEG we directly investigated how these visual signals interact with rhythmic brain activity in participants listening to and seeing the speaker. First, we investigated coherence between oscillatory brain activity and speaker's lip movements and demonstrated significant entrainment in visual cortex. We then used partial coherence to remove contributions of the coherent auditory speech signal from the lip-brain coherence. Comparing this synchronization between different attention conditions revealed that attending visual speech enhances the coherence between activity in visual cortex and the speaker's lips. Further, we identified a significant partial coherence between left motor cortex and lip movements and this partial coherence directly predicted comprehension accuracy. Our results emphasize the importance of visually entrained and attention-modulated rhythmic brain activity for the enhancement of audiovisual speech processing.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Puig2016,

title = {Attentional selection accompanied by eye vergence as revealed by event-related brain potentials},

author = {Maria Solé Puig and Josep Marco Pallarés and Laura Perez Zapata and Laura Puigcerver and Josep Cañete and Hans Supèr},

doi = {10.1371/journal.pone.0167646},

year  = {2016},

date = {2016-01-01},

journal = {PLoS ONE},

volume = {11},

number = {12},

pages = {e0167646},

abstract = {Neural mechanisms of attention allow selective sensory information processing. Top-down deployment of visual-spatial attention is conveyed by cortical feedback connections from frontal regions to lower sensory areas modulating late stimulus responses. A recent study reported the occurrence of small eye vergence during orienting top-down attention. Here we assessed a possible link between vergence and attention by comparing visual event related potentials (vERPs) to a cue stimulus that induced attention to shift towards the target location to the vERPs to a no-cue stimulus that did not trigger orienting attention. The results replicate the findings of eye vergence responses during orienting attention and show that the strength and time of eye vergence coincide with the onset and strength of the vERPs when subjects oriented attention. Our findings therefore support the idea that eye vergence relates to and possibly has a role in attentional selection.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Ramkumar2016,

title = {Visual information representation and rapid-scene categorization are simultaneous across cortex: An MEG study},

author = {Pavan Ramkumar and Bruce C. Hansen and Sebastian Pannasch and Lester C. Loschky},

doi = {10.1016/j.neuroimage.2016.03.027},

year  = {2016},

date = {2016-01-01},

journal = {NeuroImage},

volume = {134},

pages = {295–304},

publisher = {Elsevier Inc.},

abstract = {Perceiving the visual world around us requires the brain to represent the features of stimuli and to categorize the stimulus based on these features. Incorrect categorization can result either from errors in visual representation or from errors in processes that lead to categorical choice. To understand the temporal relationship between the neural signatures of such systematic errors, we recorded whole-scalp magnetoencephalography (MEG) data from human subjects performing a rapid-scene categorization task. We built scene category decoders based on (1) spatiotemporally resolved neural activity, (2) spatial envelope (SpEn) image features, and (3) behavioral responses. Using confusion matrices, we tracked how well the pattern of errors from neural decoders could be explained by SpEn decoders and behavioral errors, over time and across cortical areas. Across the visual cortex and the medial temporal lobe, we found that both SpEn and behavioral errors explained unique variance in the errors of neural decoders. Critically, these effects were nearly simultaneous, and most prominent between 100 and 250 ms after stimulus onset. Thus, during rapid-scene categorization, neural processes that ultimately result in behavioral categorization are simultaneous and co-localized with neural processes underlying visual information representation.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Saproo2016,

title = {Neural mechanisms underlying catastrophic failure in human-machine interaction during aerial navigation},

author = {Sameer Saproo and Victor Shih and David C. Jangraw and Paul Sajda},

doi = {10.1088/1741-2560/13/6/066005},

year  = {2016},

date = {2016-01-01},

journal = {Journal of Neural Engineering},

volume = {13},

pages = {1–12},

abstract = {Objective. We investigated the neural correlates of workload buildup in a fine visuomotor task called the boundary avoidance task (BAT). The BAT has been known to induce naturally occurring failures of human–machine coupling in high performance aircraft that can potentially lead to a crash—these failures are termed pilot induced oscillations (PIOs). Approach. We recorded EEG and pupillometry data from human subjects engaged in a flight BAT simulated within a virtual 3D environment. Main results. We find that workload buildup in a BAT can be successfully decoded from oscillatory features in the electroencephalogram (EEG). Information in delta, theta, alpha, beta, and gamma spectral bands of the EEG all contribute to successful decoding, however gamma band activity with a lateralized somatosensory topography has the highest contribution, while theta band activity with a fronto-central topography has the most robust contribution in terms of real-world usability. We show that the output of the spectral decoder can be used to predict PIO susceptibility. We also find that workload buildup in the task induces pupil dilation, the magnitude of which is significantly correlated with the magnitude of the decoded EEG signals. These results suggest that PIOs may result from the dysregulation of cortical networks such as the locus coeruleus (LC)—anterior cingulate cortex (ACC) circuit. Significance. Our findings may generalize to similar control failures in other cases of tight manmachine coupling where gains and latencies in the control system must be inferred and compensated for by the human operators. A closed-loop intervention using neurophysiological decoding of workload buildup that targets the LC-ACC circuit may positively impact operator performance in such situations.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Bodala2016,

title = {EEG and eye tracking demonstrate vigilance enhancement with challenge integration},

author = {Indu P. Bodala and Junhua Li and Nitish V. Thakor and Hasan Al-Nashash},

doi = {10.3389/fnhum.2016.00273},

year  = {2016},

date = {2016-01-01},

journal = {Frontiers in Human Neuroscience},

volume = {10},

pages = {273},

abstract = {Maintaining vigilance is possibly the first requirement for surveillance tasks where personnel are faced with monotonous yet intensive monitoring tasks. Decrement in vigilance in such situations could result in dangerous consequences such as accidents, loss of life and system failure. In this paper, we investigate the possibility to enhance vigilance or sustained attention using ‘challenge integration', a strategy that integrates a primary task with challenging stimuli. A primary surveillance task (identifying an intruder in a simulated factory environment) and a challenge stimulus (periods of rain obscuring the surveillance scene) were employed to test the changes in vigilance levels. The effect of integrating challenging events (resulting from artificially simulated rain) into the task were compared to the initial monotonous phase. EEG and eye tracking data is collected and analyzed for n = 12 subjects. Frontal midline theta power and frontal theta to parietal alpha power ratio which are used as measures of engagement and attention allocation show an increase due to challenge integration (p < 0.05 in each case). Relative delta band power of EEG also shows statistically significant suppression on the frontoparietal and occipital cortices due to challenge integration (p < 0.05). Saccade amplitude, saccade velocity and blink rate obtained from eye tracking data exhibit statistically significant changes during the challenge phase of the experiment (p < 0.05 in each case). From the correlation analysis between the statistically significant measures of eye tracking and EEG, we infer that saccade amplitude and saccade velocity decrease with vigilance decrement along with frontal midline theta and frontal theta to parietal alpha ratio. Conversely, blink rate and relative delta power increase with vigilance decrement. However, these measures exhibit a reverse trend when challenge stimulus appears in the task suggesting vigilance enhancement. Moreover, the mean reaction time is lower for the challenge integrated phase (RT mean = 3.65 ± 1.4 secs) compared to initial monotonous phase without challenge (RT mean = 4.6 ± 2.7 secs). Our work shows that vigilance level, as assessed by response of these vital signs, is enhanced by challenge integration.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Campana2016,

title = {Conscious vision proceeds from global to local content in goal-directed tasks and spontaneous vision},

author = {Florence Campana and Ignacio Rebollo and Anne E. Urai and Valentin Wyart and Catherine Tallon-Baudry},

doi = {10.1523/JNEUROSCI.3619-15.2016},

year  = {2016},

date = {2016-01-01},

journal = {Journal of Neuroscience},

volume = {36},

number = {19},

pages = {5200–5213},

abstract = {The reverse hierarchy theory (Hochstein and Ahissar, 2002) makes strong, but so far untested, predictions on conscious vision. In this theory, local details encoded in lower-order visual areas are unconsciously processed before being automatically and rapidly combined into global information in higher-order visual areas, where conscious percepts emerge. Contingent on current goals, local details can afterward be consciously retrieved. This model therefore predicts that (1) global information is perceived faster than local details, (2) global information is computed regardless of task demands during early visual processing, and (3) spontaneous vision is dominated by global percepts. We designed novel textured stimuli that are, as opposed to the classic Navon's letters, truly hierarchical (i.e., where global information is solely defined by local information but where local and global orientations can still be manipulated separately). In line with the predictions, observers were systematically faster reporting global than local properties of those stimuli. Second, global information could be decoded from magneto-encephalographic data during early visual processing regardless of task demands. Last, spontaneous subjective reports were dominated by global information and the frequency and speed of spontaneous global perception correlated with the accuracy and speed in the global task. No such correlation was observed for local information. We therefore show that information at different levels of the visual hierarchy is not equally likely to become conscious; rather, conscious percepts emerge preferentially at a global level. We further show that spontaneous reports can be reliable and are tightly linked to objective performance at the global level.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Chen2016d,

title = {LRP predicts smooth pursuit eye movement onset during the ocular tracking of self-generated movements},

author = {Jing Chen and Matteo Valsecchi and Karl R. Gegenfurtner},

doi = {10.1152/jn.00184.2016},

year  = {2016},

date = {2016-01-01},

journal = {Journal of Neurophysiology},

volume = {116},

number = {1},

pages = {18–29},

abstract = {Several studies indicated that human observers are very efficient at tracking self-generated hand movements with their gaze, yet it is not clear whether this is simply a byproduct of the predictability of self-generated actions or if it results from a deeper coupling of the somatomotor and oculomotor systems. In a first behavioral experiment we compared pursuit performance as observers either followed their own finger or tracked a dot whose motion was externally generated but mimicked their finger motion. We found that even when the dot motion was completely predictable both in terms of onset time and in terms of kinematics, pursuit was not identical to the one produced as the observers tracked their finger, as evidenced by increased rate of catch-up saccades and by the fact that in the initial phase of the movement gaze was lagging behind the dot, whereas it was ahead of the finger. In a second experiment we recorded EEG in the attempt to find a direct link between the finger motor preparation, indexed by the lateralized readiness potential (LRP), and the latency of smooth pursuit. After taking into account finger movement onset variability, we observed larger LRP amplitudes associated with earlier smooth pursuit onset across trials. The same held across subjects, where average LRP onset correlated with average eye latency. The evidence from both experiments concurs to indicate that a strong coupling exists between the motor systems leading to eye and finger movements and that simple top-down predictive signals are unlikely to support optimal coordination.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Choi2016,

title = {Synchronized tracking of brain cognitive processing using EEG and vision signals},

author = {Hak Soo Choi and Shinjung Kim and Donghoon Lee and Chang Seok Kim and Myung Yung Jeong},

doi = {10.1080/05704928.2016.1166373},

year  = {2016},

date = {2016-01-01},

journal = {Applied Spectroscopy Reviews},

volume = {51},

number = {7-9},

pages = {592–602},

publisher = {Taylor & Francis},

abstract = {Many efforts have been made to understand the neural mechanisms of the human brain. However, visualization of human brain processing has been a main challenge in the field. It is still largely unknown how the human brain allocates attention to target objects while excluding unrelated information in a complex visual environment. Using simultaneous electroencephalogram and eye tracking measurements, in this study, we analyzed two brain regions separately to detect the brain wave activity during visual information processing. We observed an activation difference between sensory (P100) and cognitive (P300) processing, and the behavioral response was improved by providing valid cue-target location information. Furthermore, neural processing was evaluated according to the specific area of brain activation and eye movements during cognitive processing. Our results demonstrate the correlation between behavior performance and visual stimuli and suggest an advantage of combined paradigms for efficient visual information processing.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Shigihara2016,

title = {Early visual cortical responses produced by checkerboard pattern stimulation},

author = {Yoshihito Shigihara and Hideyuki Hoshi and Semir Zeki},

doi = {10.1016/j.neuroimage.2016.03.078},

year  = {2016},

date = {2016-01-01},

journal = {NeuroImage},

volume = {134},

pages = {532–539},

publisher = {Elsevier B.V.},

abstract = {Visual evoked potentials have been traditionally triggered with flash or reversing checkerboard stimuli and recorded with electroencephalographic techniques, largely but not exclusively in clinical or clinically related settings. They have been crucial in determining the healthy functioning or otherwise of the visual pathways up to and including the cerebral cortex. They have typically given early response latencies of 100 ms, the source of which has been attributed to V1, with the prestriate cortex being secondarily activated somewhat later. On the other hand, magnetoencephalographic studies using stimuli better tailored to the physiology of individual, specialized, visual areas have given early latencies of <. 50 ms with the sources localized in both striate (V1) and prestriate cortex. In this study, we used the reversing checkerboard pattern as a stimulus and recorded cortical visual evoked magnetic fields with magnetoencephalography, to establish whether very early responses can be traced to (estimated) in both striate and prestriate cortex, since such a demonstration would enhance considerably the power of this classical approach in clinical investigations. Our results show that cortical responses evoked by checkerboard patterns can be detected before 50 ms post-stimulus onset and that their sources can be estimated in both striate and prestriate cortex, suggesting a strong parallel input from the sub-cortex to both striate and prestriate divisions of the visual cortex.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Shishkin2016,

title = {EEG negativity in fixations used for gaze-based control: Toward converting intentions into actions with an eye-brain-computer interface},

author = {Sergei L. Shishkin and Yuri O. Nuzhdin and Evgeny P. Svirin and Alexander G. Trofimov and Anastasia A. Fedorova and Bogdan L. Kozyrskiy and Boris M. Velichkovsky},

doi = {10.3389/fnins.2016.00528},

year  = {2016},

date = {2016-01-01},

journal = {Frontiers in Neuroscience},

volume = {10},

pages = {528},

abstract = {We usually look at an object when we are going to manipulate it. Thus, eye tracking can be used to communicate intended actions. An effective human-machine interface, however, should be able to differentiate intentional and spontaneous eye movements. We report an electroencephalogram (EEG) marker that differentiates gaze fixations used for control from spontaneous fixations involved in visual exploration. Eight healthy participants played a game with their eye movements only. Their gaze-synchronized EEG data (fixation-related potentials, FRPs) were collected during game's control-on and control-off conditions. A slow negative wave with a maximum in the parietooccipital region was present in each participant's averaged FRPs in the control-on conditions and was absent or had much lower amplitude in the control-off condition. This wave was similar but not identical to stimulus-preceding negativity, a slow negative wave that can be observed during feedback expectation. Classification of intentional vs. spontaneous fixations was based on amplitude features from 13 EEG channels using 300 ms length segments free from electrooculogram contamination (200..500 ms relative to the fixation onset). For the first fixations in the fixation triplets required to make moves in the game, classified against control-off data, a committee of greedy classifiers provided 0.90 ± 0.07 specificity and 0.38 ± 0.14 sensitivity. Similar (slightly lower) results were obtained for the shrinkage LDA classifier. The second and third fixations in the triplets were classified at lower rate. We expect that, with improved feature sets and classifiers, a hybrid dwell-based Eye-Brain-Computer Interface (EBCI) can be built using the FRP difference between the intended and spontaneous fixations. If this direction of BCI development will be successful, such a multimodal interface may improve the fluency of interaction and can possibly become the basis for a new input device for paralyzed and healthy users, the EBCI “Wish Mouse”.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Spaak2016,

title = {The neural mechanisms of prediction in visual search},

author = {Eelke Spaak and Yvonne Fonken and Ole Jensen and Floris P. Lange},

doi = {10.1093/cercor/bhv210},

year  = {2016},

date = {2016-01-01},

journal = {Cerebral Cortex},

volume = {26},

number = {11},

pages = {4327–4336},

abstract = {The speed of visual search depends on bottom-up stimulus features (e.g., we quickly locate a red item among blue distractors), but it is also facilitated by the presence of top-down perceptual predictions about the item. Here, we identify the nature, source, and neuronal substrate of the predictions that speed up resumed visual search. Human subjects were presented with a visual search array that was repeated up to 4 times, while brain activity was recorded using magnetoencephalography (MEG). Behaviorally, we observed a bimodal reaction time distribution for resumed visual search, indicating that subjects were extraordinarily rapid on a proportion of trials. MEG data demonstrated that these rapid-response trials were associated with a prediction of (1) target location, as reflected by alpha-band (8-12 Hz) lateralization; and (2) target identity, as reflected by beta-band (15-30 Hz) lateralization. Moreover, we show that these predictions are likely generated in a network consisting of medial superior frontal cortex and right temporo-parietal junction. These findings underscore the importance and nature of perceptual hypotheses for efficient visual search.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Tan2016,

title = {MEG sensor and source measures of visually induced gamma-band oscillations are highly reliable},

author = {Heng Ru May Tan and Joachim Gross and P. J. Uhlhaas},

doi = {10.1016/j.neuroimage.2016.05.006},

year  = {2016},

date = {2016-01-01},

journal = {NeuroImage},

volume = {137},

pages = {34–44},

publisher = {The Authors},

abstract = {High frequency brain oscillations are associated with numerous cognitive and behavioral processes. Non-invasive measurements using electro-/magnetoencephalography (EEG/MEG) have revealed that high frequency neural signals are heritable and manifest changes with age as well as in neuropsychiatric illnesses. Despite the extensive use of EEG/MEG-measured neural oscillations in basic and clinical research, studies demonstrating test-retest reliability of power and frequency measures of neural signals remain scarce. Here, we evaluated the test-retest reliability of visually induced gamma (30-100 Hz) oscillations derived from sensor and source signals acquired over two MEG sessions. The study required participants (N = 13) to detect the randomly occurring stimulus acceleration while viewing a moving concentric grating. Sensor and source MEG measures of gamma-band activity yielded comparably strong reliability (average intraclass correlation},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Nieuwenhuijzen2016,

title = {Spatiotemporal dynamics of cortical representations during and after stimulus presentation},

author = {Marieke E. Nieuwenhuijzen and Eva W. P. Borne and Ole Jensen and Marcel A. J. Gerven},

doi = {10.3389/fnsys.2016.00042},

year  = {2016},

date = {2016-01-01},

journal = {Frontiers in Systems Neuroscience},

volume = {10},

pages = {42},

abstract = {Visual perception is a spatiotemporally complex process. In this study, we investigated cortical dynamics during and after stimulus presentation. We observed that visual category information related to the difference between faces and objects became apparent in the occipital lobe after 63 ms. Within the next 110 ms, activation spread out to include the temporal lobe before returning to residing mainly in the occipital lobe again. After stimulus offset, a peak in information was observed, comparable to the peak after stimulus onset. Moreover, similar processes, albeit not identical, seemed to underlie both peaks. Information about the categorical identity of the stimulus remained present until 677 ms after stimulus offset, during which period the stimulus had to be retained in working memory. Activation patterns initially resembled those observed during stimulus presentation. After about 200 ms, however, this representation changed and class-specific activity became more equally distributed over the four lobes. These results show that, although there are common processes underlying stimulus representation both during and after stimulus presentation, these representations change depending on the specific stage of perception and maintenance.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Diepen2016,

title = {The role of alpha activity in spatial and feature-based attention.},

author = {Rosanne M. Diepen and Lee M. Miller and Ali Mazaheri and Joy J. Geng},

doi = {10.1523/ENEURO.0204-16.2016},

year  = {2016},

date = {2016-01-01},

journal = {eNeuro},

volume = {3},

number = {5},

pages = {1–11},

abstract = {Modulations in alpha oscillations (?10 Hz) are typically studied in the context of anticipating upcoming stimuli. Alpha power decreases in sensory regions processing upcoming targets compared to regions processing distracting input, thereby likely facilitating processing of relevant information while suppressing irrelevant. In this electroencephalography study using healthy human volunteers, we examined whether modulations in alpha power also occur after the onset of a bilaterally presented target and distractor. Spatial attentionwasmanipulated through spatial cues and feature-based attention through adjusting the color-similarity of distractors to the target. Consistent with previous studies, we found that informative spatial cues induced a relative decrease of pretarget alpha power at occipital electrodes contralateral to the expected target location. Interestingly, this pattern reemerged relatively late (300–750 ms) after stimulus onset, suggesting that lateralized alpha reflects not only preparatory attention, but also ongoing attentive stimulus processing. Uninformative cues (i.e., conveying no information about the spatial location of the target) resulted in an interaction between spatial attention and feature-based attention in post-target alpha lateralization. When the target was paired with a low-similarity distractor, post-target alpha was lateralized (500–900 ms). Crucially, the lateralization was absent when target selection was ambig- uous because the distractor was highly similar to the target. Instead, during this condition, midfrontal theta was increased, indicative of reactive conflict resolution. Behaviorally, the degree of alpha lateralization was negatively correlated with the reaction time distraction cost induced by target–distractor similarity. These results suggest a pivotal role for poststimulus alpha lateralization in protecting sensory processing of target information.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Vignali2016,

title = {Oscillatory brain dynamics during sentence reading: A fixation-related spectral perturbation analysis},

author = {Lorenzo Vignali and Nicole A. Himmelstoss and Stefan Hawelka and Fabio Richlan and Florian Hutzler},

doi = {10.3389/fnhum.2016.00191},

year  = {2016},

date = {2016-01-01},

journal = {Frontiers in Human Neuroscience},

volume = {10},

pages = {191},

abstract = {The present study investigated oscillatory brain dynamics during self-paced sentence-level processing. Participants read fully correct sentences, sentences containing a semantic violation and "sentences" in which the order of the words was randomized. At the target word level, fixations on semantically unrelated words elicited a lower-beta band (13-18 Hz) desynchronization. At the sentence level, gamma power (31-55 Hz) increased linearly for syntactically correct sentences, but not when the order of the words was randomized. In the 300-900 ms time window after sentence onsets, theta power (4-7 Hz) was greater for syntactically correct sentences as compared to sentences where no syntactic structure was preserved (random words condition). We interpret our results as conforming with a recently formulated predictive-coding framework for oscillatory neural dynamics during sentence-level language comprehension. Additionally, we discuss how our results relate to previous findings with serial visual presentation vs. self-paced reading.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Devillez2015,

title = {An eye fixation–related potentials analysis of the P300 potential for fixations onto a target object when exploring natural scenes},

author = {Hélène Devillez and Nathalie Guyader and Anne Guérin-Dugué},

doi = {10.1167/15.13.20},

year  = {2015},

date = {2015-09-01},

journal = {Journal of Vision},

volume = {15},

number = {13},

pages = {20},

abstract = {The P300 event-related potential has been extensively studied in electroencephalography with classical paradigms that force observers to not move their eyes. This potential is classically used to infer whether a target or a task-relevant stimulus was presented. Few researches have studied this potential through more ecological paradigms where observers were able to move their eyes. In this study, we examined with an ecological paradigm and an adapted methodology the P300 potential using a visual search task that involves eye movements to actively explore natural scenes and during which eye movements and electroencephalographic activity were coregistered. Averaging the electroencephalography signal time-locked to fixation onsets, a P300 potential was observed for fixations onto the target object but not for other fixations recorded for the same visual search or for fixations recorded during the free viewing without any task. Our approach consists of using control experimental conditions with similar eye movements to ensure that the P300 potential was attributable to the fact that the observer gazed at the target rather than to other factors such as eye movement pattern (the size of the previous saccade) or the ‘‘overlap issue'' between the potentials elicited by two successive fixations. We also proposed to model the time overlap issue of the potentials elicited by consecutive fixations with various durations. Our results show that the P300 potential can be studied in ecological situations without any constraint on the type of visual exploration, with some precautions in the interpretation of results due to the overlap issue.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Caruana2015a,

title = {The neural time course of evaluating self-initiated joint attention bids},

author = {Nathan Caruana and Peter Lissa and Genevieve McArthur},

doi = {10.1016/j.bandc.2015.06.001},

year  = {2015},

date = {2015-01-01},

journal = {Brain and Cognition},

volume = {98},

pages = {43–52},

publisher = {Elsevier Inc.},

abstract = {Background: During interactions with other people, we constantly evaluate the significance of our social partner's gaze shifts in order to coordinate our behaviour with their perspective. In this study, we used event-related potentials (ERPs) to investigate the neural time course of evaluating gaze shifts that signal the success of self-initiated joint attention bids. Method: Nineteen participants were allocated to a "social" condition, in which they played a cooperative game with an anthropomorphic virtual character whom they believed was controlled by a human partner in a nearby laboratory. Participants were required to initiate joint attention towards a target. In response, the virtual partner shifted his gaze congruently towards the target - thus achieving joint attention - or incongruently towards a different location. Another 19 participants completed the same task in a non-social "control" condition, in which arrows, believed to be controlled by a computer program, pointed at a location that was either congruent or incongruent with the participant's target fixation. Results: In the social condition, ERPs to the virtual partner's incongruent gaze shifts evoked significantly larger P350 and P500 peaks compared to congruent gaze shifts. This P350 and P500 morphology was absent in both the congruent and incongruent control conditions. Discussion: These findings are consistent with previous claims that gaze shifts differing in their social significance modulate central-parietal ERPs 350. ms following the onset of the gaze shift. Our control data highlights the social specificity of the observed P350 effect, ruling out explanations pertaining to attention modulation or error detection.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Cleeren2015,

title = {Ictal perfusion changes associated with seizure progression in the amygdala kindling model in the rhesus monkey},

author = {Evy Cleeren and Cindy Casteels and Karolien Goffin and Peter Janssen and Wim Van Paesschen},

doi = {10.1111/epi.13077},

year  = {2015},

date = {2015-01-01},

journal = {Epilepsia},

volume = {56},

number = {9},

pages = {1366–1375},

abstract = {OBJECTIVE: Amygdala kindling is a widely used animal model for studying mesial temporal lobe epileptogenesis. In the macaque monkey, electrical amygdala kindling develops slowly and provides an opportunity for investigating ictal perfusion changes during epileptogenesis. METHODS: Two rhesus monkeys were electrically kindled through chronically implanted electrodes in the right amygdala over a period of 16 and 17 months. Ictal perfusion single photon emission computed tomography (SPECT) imaging was performed during each of the four predefined clinical stages. RESULTS: Afterdischarge duration increased slowly over 477 days for monkey K and 515 days for monkey S (18 ± 8 s in stage I; 52 ± 13 s in stage IV). During this time, the animals progressed through four clinical stages ranging from interrupting ongoing behavior to bilateral convulsions. Ictal SPECT perfusion imaging showed well-localized but widely distributed regions of hyperperfusion and hypoperfusion, in both cortical and subcortical structures, at every seizure stage. A large portion of the ictal network was involved in the early stages of epileptogenesis and subsequently expanded over time as seizure severity evolved. SIGNIFICANCE: Our data indicate that the different mesial temporal lobe seizure types occur within a common network affecting several parts of the brain, and that seizure severity may be determined by seizure-induced epileptogenesis within a bihemispheric network that is implicated from the start of the process.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Diwakar2015,

title = {Filling in the gaps: Anticipatory control of eye movements in chronic mild traumatic brain injury},

author = {Mithun Diwakar and Deborah L. Harrington and Jun Maruta and Jamshid Ghajar and Fady El-Gabalawy and Laura Muzzatti and Maurizio Corbetta and Ming-Xiong X. Huang and Roland R. Lee},

doi = {10.1016/j.nicl.2015.04.011},

year  = {2015},

date = {2015-01-01},

journal = {NeuroImage: Clinical},

volume = {8},

pages = {210–223},

publisher = {Elsevier B.V.},

abstract = {A barrier in the diagnosis of mild traumatic brain injury (mTBI) stems from the lack of measures that are adequately sensitive in detecting mild head injuries. MRI and CT are typically negative in mTBI patients with persistent symptoms of post-concussive syndrome (PCS), and characteristic difficulties in sustaining attention often go undetected on neuropsychological testing, which can be insensitive to momentary lapses in concentration. Conversely, visual tracking strongly depends on sustained attention over time and is impaired in chronic mTBI patients, especially when tracking an occluded target. This finding suggests deficient internal anticipatory control in mTBI, the neural underpinnings of which are poorly understood. The present study investigated the neuronal bases for deficient anticipatory control during visual tracking in 25 chronic mTBI patients with persistent PCS symptoms and 25 healthy control subjects. The task was performed while undergoing magnetoencephalography (MEG), which allowed us to examine whether neural dysfunction associated with anticipatory control deficits was due to altered alpha, beta, and/or gamma activity. Neuropsychological examinations characterized cognition in both groups. During MEG recordings, subjects tracked a predictably moving target that was either continuously visible or randomly occluded (gap condition). MEG source-imaging analyses tested for group differences in alpha, beta, and gamma frequency bands. The results showed executive functioning, information processing speed, and verbal memory deficits in the mTBI group. Visual tracking was impaired in the mTBI group only in the gap condition. Patients showed greater error than controls before and during target occlusion, and were slower to resynchronize with the target when it reappeared. Impaired tracking concurred with abnormal beta activity, which was suppressed in the parietal cortex, especially the right hemisphere, and enhanced in left caudate and frontaloral areas. Regional beta-amplitude demonstrated high classification accuracy (92%) compared to eye-tracking (65%) and neuropsychological variables (80%). These findings show that deficient internal anticipatory control in mTBI is associated with altered beta activity, which is remarkably sensitive given the heterogeneity of injuries.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Ehinger2015,

title = {Predictions of visual content across eye movements and their modulation by inferred information},

author = {Benedikt V. Ehinger and Peter Konig and José P. Ossandón},

doi = {10.1523/JNEUROSCI.5114-14.2015},

year  = {2015},

date = {2015-01-01},

journal = {Journal of Neuroscience},

volume = {35},

number = {19},

pages = {7403–7413},

abstract = {The brain is proposed to operate through probabilistic inference, testing and refining predictions about the world. Here, we search for neural activity compatible with the violation of active predictions, learned from the contingencies between actions and the consequent changes in sensory input. We focused on vision, where eye movements produce stimuli shifts that could, in principle, be predicted. We compared, in humans, error signals to saccade-contingent changes of veridical and inferred inputs by contrasting the electroencephalographic activity after saccades to a stimulus presented inside or outside the blind spot. We observed early (<250 ms) and late (>250 ms) error signals after stimulus change, indicating the violation of sensory and associative predictions, respectively. Remarkably, the late response was diminished for blind-spot trials. These results indicate that predictive signals occur across multiple levels of the visual hierarchy, based on generative models that differentiate between signals that originate from the outside world and those that are inferred.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Kauppi2015,

title = {Towards brain-activity-controlled information retrieval: Decoding image relevance from MEG signals},

author = {Jukka Pekka Kauppi and Melih Kandemir and Veli Matti Saarinen and Lotta Hirvenkari and Lauri Parkkonen and Arto Klami and Riitta Hari and Samuel Kaski},

doi = {10.1016/j.neuroimage.2014.12.079},

year  = {2015},

date = {2015-01-01},

journal = {NeuroImage},

volume = {112},

pages = {288–298},

publisher = {Elsevier Inc.},

abstract = {We hypothesize that brain activity can be used to control future information retrieval systems. To this end, we conducted a feasibility study on predicting the relevance of visual objects from brain activity. We analyze both magnetoencephalographic (MEG) and gaze signals from nine subjects who were viewing image collages, a subset of which was relevant to a predetermined task. We report three findings: i) the relevance of an image a subject looks at can be decoded from MEG signals with performance significantly better than chance, ii) fusion of gaze-based and MEG-based classifiers significantly improves the prediction performance compared to using either signal alone, and iii) non-linear classification of the MEG signals using Gaussian process classifiers outperforms linear classification. These findings break new ground for building brain-activity-based interactive image retrieval systems, as well as for systems utilizing feedback both from brain activity and eye movements.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Kloosterman2015,

title = {Top-down modulation in human visual cortex predicts the stability of a perceptual illusion},

author = {Niels A. Kloosterman and Thomas Meindertsma and Arjan Hillebrand and Bob W. Dijk and Victor A. F. Lamme and Tobias H. Donner},

doi = {10.1152/jn.00338.2014},

year  = {2015},

date = {2015-01-01},

journal = {Journal of Neurophysiology},

volume = {113},

number = {4},

pages = {1063–1076},

abstract = {Conscious perception sometimes fluctuates strongly, even when the sensory input is constant. For example, in motion-induced blindness (MIB), a salient visual target surrounded by a moving pattern suddenly disappears from perception, only to reappear after some variable time. Whereas such changes of perception result from fluctuations of neural activity, mounting evidence suggests that the perceptual changes, in turn, may also cause modulations of activity in several brain areas, including visual cortex. In this study, we asked whether these latter modulations might affect the subsequent dynamics of perception. We used magnetoencephalography (MEG) to measure modulations in cortical population activity during MIB. We observed a transient, retinotopically widespread modulation of beta (12-30 Hz)-frequency power over visual cortex that was closely linked to the time of subjects' behavioral report of the target disappearance. This beta modulation was a top-down signal, decoupled from both the physical stimulus properties and the motor response but contingent on the behavioral relevance of the perceptual change. Critically, the modulation amplitude predicted the duration of the subsequent target disappearance. We propose that the transformation of the perceptual change into a report triggers a top-down mechanism that stabilizes the newly selected perceptual interpretation.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Kretzschmar2015,

title = {Dissociating word frequency and predictability effects in reading: Evidence from coregistration of eye movements and EEG},

author = {Franziska Kretzschmar and Matthias Schlesewsky and Adrian Staub},

doi = {10.1037/xlm0000128},

year  = {2015},

date = {2015-01-01},

journal = {Journal of Experimental Psychology: Learning, Memory, and Cognition},

volume = {41},

number = {6},

pages = {1648–1662},

abstract = {Two very reliable influences on eye fixation durations in reading are word frequency, as measured by corpus counts, and word predictability, as measured by cloze norming. Several studies have reported strictly additive effects of these 2 variables. Predictability also reliably influences the amplitude of the N400 component in event-related potential studies. However, previous research suggests that while frequency affects the N400 in single-word tasks, it may have little or no effect on the N400 when a word is presented with a preceding sentence context. The present study assessed this apparent dissociation between the results from the 2 methods using a coregistration paradigm in which the frequency and predictability of a target word were manipulated while readers' eye movements and electroencephalograms were simultaneously recorded. We replicated the pattern of significant, and additive, effects of the 2 manipulations on eye fixation durations. We also replicated the predictability effect on the N400, time-locked to the onset of the reader's first fixation on the target word. However, there was no indication of a frequency effect in the electroencephalogram record. We suggest that this pattern has implications both for the interpretation of the N400 and for the interpretation of frequency and predictability effects in language comprehension.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Krigolson2015,

title = {The impact of cognitive load on reward evaluation},

author = {Olave E. Krigolson and Cameron D. Hassall and Jason Satel and Raymond M. Klein},

doi = {10.1016/j.brainres.2015.09.028},

year  = {2015},

date = {2015-01-01},

journal = {Brain Research},

volume = {1627},

pages = {225–232},

publisher = {Elsevier},

abstract = {The neural systems that afford our ability to evaluate rewards and punishments are impacted by a variety of external factors. Here, we demonstrate that increased cognitive load reduces the functional efficacy of a reward processing system within the human medial–frontal cortex. In our paradigm, two groups of participants used performance feedback to estimate the exact duration of one second while electroencephalographic (EEG) data was recorded. Prior to performing the time estimation task, both groups were instructed to keep their eyes still and avoid blinking in line with well established EEG protocol. However, during performance of the time-estimation task, one of the two groups was provided with trial-to-trial-feedback about their performance on the time-estimation task and their eye movements to induce a higher level of cognitive load relative to participants in the other group who were solely provided with feedback about the accuracy of their temporal estimates. In line with previous work, we found that the higher level of cognitive load reduced the amplitude of the feedback-related negativity, a component of the human event-related brain potential associated with reward evaluation within the medial–frontal cortex. Importantly, our results provide further support that increased cognitive load reduces the functional efficacy of a neural system associated with reward processing.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Leiken2015,

title = {Filling predictable and unpredictable gaps, with and without similarity-based interference: Evidence for LIFG effects of dependency processing},

author = {Kimberly Leiken and Brian McElree and Liina Pylkkänen},

doi = {10.3389/fpsyg.2015.01739},

year  = {2015},

date = {2015-01-01},

journal = {Frontiers in Psychology},

volume = {6},

pages = {1739},

abstract = {One of the most replicated findings in neurolinguistic literature on syntax is the increase of hemodynamic activity in the left inferior frontal gyrus (LIFG) in response to object relative (OR) clauses compared to subject relative clauses. However, behavioral studies have shown that ORs are primarily only costly when similarity-based interference is involved and recently, Leiken and Pylkkänen (2014) showed with magnetoencephalography (MEG) that an LIFG increase at an OR gap is also dependent on such interference. However, since ORs always involve a cue indicating an upcoming dependency formation, OR dependencies could be processed already prior to the gap-site and thus show no sheer dependency effects at the gap itself. To investigate the role of gap predictability in LIFG dependency effects, this MEG study compared ORs to verb phrase ellipsis (VPE), which was used as an example of a non-predictable dependency. Additionally, we explored LIFG sensitivity to filler-gap order by including right node raising structures, in which the order of filler and gap is reverse to that of ORs and VPE. Half of the stimuli invoked similarity-based interference and half did not. Our results demonstrate that LIFG effects of dependency can be elicited regardless of whether the dependency is predictable, the stimulus materials evoke similarity-based interference, or the filler precedes the gap. Thus, contrary to our own prior data, the current findings suggest a highly general role for the LIFG in dependency interpretation that is not limited to environments involving similarity-based interference. Additionally, the millisecond time-resolution of MEG allowed for a detailed characterization of the temporal profiles of LIFG dependency effects across our three constructions, revealing that the timing of these effects is somewhat construction-specific.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Li2015a,

title = {A study on EEG-based brain electrical source of mild depressed subjects},

author = {Xiaowei Li and Bin Hu and Tingting Xu and Ji Shen and Martyn Ratcliffe},

doi = {10.1016/j.cmpb.2015.04.009},

year  = {2015},

date = {2015-01-01},

journal = {Computer Methods and Programs in Biomedicine},

volume = {120},

number = {3},

pages = {135–141},

publisher = {Elsevier Ireland Ltd},

abstract = {Background and objective: Several abnormal brain regions are known to be linked to depression, including amygdala, orbitofrontal cortex (OFC), anterior cingulate cortex (ACC), and dorsolateral prefrontal cortex (DLPFC) etc. The aim of this study is to apply EEG (electroencephalogram) data analysis to investigate, with respect to mild depression, whether there exists dysregulation in these brain regions. Methods: EEG sources were assessed from 9 healthy and 9 mildly depressed subjects who were classified according to the Beck Depression Inventory (BDI) criteria. t-Test was used to calculate the eye movement data and standardized low resolution tomography (sLORETA) was used to correlate EEG activity. Results: A comparison of eye movement data between the healthy and mild depressed subjects exhibited that mildly depressed subjects spent more time viewing negative emotional faces. Comparison of the EEG from the two groups indicated higher theta activity in BA6 (Brodmann area) and higher alpha activity in BA38. Conclusions: EEG source location results suggested that temporal pole activity to be dysregulated, and eye-movement data analysis exhibited mild depressed subjects paid much more attention to negative face expressions, which is also in accordance with the results of EEG source location.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Loughnane2015,

title = {Behavioral and electrophysiological evidence of opposing lateral visuospatial asymmetries in the upper and lower visual fields},

author = {Gerard M. Loughnane and John P. Shanley and Edmund C. Lalor and Redmond G. O'Connell},

doi = {10.1016/j.cortex.2014.09.003},

year  = {2015},

date = {2015-01-01},

journal = {Cortex},

volume = {63},

pages = {220–231},

publisher = {Elsevier Ltd},

abstract = {Neurologically healthy individuals typically exhibit a subtle bias towards the left visual field during spatial judgments, known as "pseudoneglect". However, it has yet to be reliably established if the direction and magnitude of this lateral bias varies along the vertical plane. Here, participants were required to distribute their attention equally across a checkerboard array spanning the entire visual field in order to detect transient targets that appeared at unpredictable locations. Reaction times (RTs) were faster to left hemifield targets in the lower visual field but the opposite trend was observed for targets in the upper field. Electroencephalogram (EEG) analyses focused on the interval prior to target onset in order to identify endogenous neural correlates of these behavioral asymmetries. The relative hemispheric distribution of pre-target oscillatory alpha power was predictive of RT bias to targets in the lower visual field but not the upper field, indicating separate attentional mechanisms for the upper and lower visual fields. Analysis of multifocal visual-evoked potentials (MVEP) in the pre-target interval also indicated that the opposing upper and lower field asymmetries may impact on the magnitude of primary visual cortical responses. These results provide new evidence of a functional segregation of upper and lower field visuospatial processing.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Maclean2015b,

title = {Neural evidence reveals the rapid effects of reward history on selective attention},

author = {Mary H. Maclean and Barry Giesbrecht},

doi = {10.1016/j.brainres.2015.02.016},

year  = {2015},

date = {2015-01-01},

journal = {Brain Research},

volume = {1606},

pages = {86–94},

publisher = {Elsevier},

abstract = {Selective attention is often framed as being primarily driven by two factors: task-relevance and physical salience. However, factors like selection and reward history, which are neither currently task-relevant nor physically salient, can reliably and persistently influence visual selective attention. The current study investigated the nature of the persistent effects of irrelevant, physically non-salient, reward-associated features. These features affected one of the earliest reliable neural indicators of visual selective attention in humans, the P1 event-related potential, measured one week after the reward associations were learned. However, the effects of reward history were moderated by current task demands. The modulation of visually evoked activity supports the hypothesis that reward history influences the innate salience of reward associated features, such that even when no longer relevant, nor physically salient, these features have a rapid, persistent, and robust effect on early visual selective attention.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Mandel2015,

title = {Brain responds to another person's eye blinks in a natural setting-the more empathetic the viewer the stronger the responses},

author = {Anne Mandel and Siiri Helokunnas and Elina Pihko and Riitta Hari},

doi = {10.1111/ejn.13011},

year  = {2015},

date = {2015-01-01},

journal = {European Journal of Neuroscience},

volume = {42},

number = {8},

pages = {2508–2514},

abstract = {An observer's brain is known to respond to another person's small nonverbal signals, such as gaze shifts and eye blinks. Here we aimed to find out how an observer's brain reacts to a speaker's eye blinks in the presence of other audiovisual information. Magnetoencephalographic brain responses along with eye gaze were recorded from 13 adults who watched a video of a person telling a story. The video was presented first without sound (visual), then with sound (audiovisual), and finally the audio story was presented with a still-frame picture on the screen (audio control). The viewers mainly gazed at the eye region of the speaker. Their saccades were suppressed at about 180 ms after the start of the speaker's blinks, a subsequent increase of saccade occurence to the base level, or higher, at around 340 ms. The suppression occurred in visual and audiovisual conditions but not during the control audio presentation. Prominent brain responses to blinks peaked in the viewer's occipital cortex at about 250 ms, with no differences in mean peak amplitudes or latencies between visual and audiovisual conditions. During the audiovisual, but not visual-only, presentation, the responses were the stronger the more empathetic the subject was according to the Empathic Concern score of the Interpersonal Reactivity Index questionnaire (Spearman's rank correlation, 0.73). The other person's eye blinks, nonverbal signs that often go unnoticed, thus elicited clear brain responses even in the presence of attention-attracting audiovisual information from the narrative, with stronger responses in people with higher empathy scores.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Manor2015,

title = {Convolutional neural network for multi-category rapid serial visual presentation BCI},

author = {Ran Manor and Amir B. Geva},

doi = {10.3389/fncom.2015.00146},

year  = {2015},

date = {2015-01-01},

journal = {Frontiers in Computational Neuroscience},

volume = {9},

pages = {146},

abstract = {Brain computer interfaces rely on machine learning (ML) algorithms to decode the brain's electrical activity into decisions. For example, in rapid serial visual presentation (RSVP) tasks, the subject is presented with a continuous stream of images containing rare target images among standard images, while the algorithm has to detect brain activity associated with target images. Here, we continue our previous work, presenting a deep neural network model for the use of single trial EEG classification in RSVP tasks. Deep neural networks have shown state of the art performance in computer vision and speech recognition and thus have great promise for other learning tasks, like classification of EEG samples. In our model, we introduce a novel spatio-temporal regularization for EEG data to reduce overfitting. We show improved classification performance compared to our earlier work on a five categories RSVP experiment. In addition, we compare performance on data from different sessions and validate the model on a public benchmark data set of a P300 speller task. Finally, we discuss the advantages of using neural network models compared to manually designing feature extraction algorithms.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Marx2015,

title = {Reward modulates perception in binocular rivalry},

author = {Svenja Marx and Wolfgang Einhäuser},

doi = {10.1167/15.1.11},

year  = {2015},

date = {2015-01-01},

journal = {Journal of Vision},

volume = {15},

number = {1},

pages = {1–13},

abstract = {Our perception does not provide us with an exact imprint of the outside world, but is continuously adapted to our internal expectations, task sets, and behavioral goals. Although effects of reward—or value in general—on perception therefore seem likely, how valuation modulates perception and how such modulation relates to attention is largely unknown. We probed effects of reward on perception by using a binocular-rivalry paradigm. Distinct gratings drifting in opposite directions were presented to each observer's eyes. To objectify their subjective perceptual experience, the optokinetic nystagmus was used as measure of current perceptual dominance. In a first experiment, one of the percepts was either rewarded or attended. We found that reward and attention similarly biased perception. In a second experiment, observers performed an attentionally demanding task either on the rewarded stimulus, the other stimulus, or both. We found that—on top of an attentional effect on perception—at each level of attentional load, reward still modulated perception by increasing the dominance of the rewarded percept. Similarly, penalizing one percept increased dominance of the other at each level of attentional load. In turn, rewarding—and similarly nonpunishing—a percept yielded performance benefits that are typically associated with selective attention. In conclusion, our data show that value modulates perception in a similar way as the volitional deployment of attention, even though the relative effect of value is largely unaffected by an attention task.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Mayerhofer2015,

title = {From incoherence to mirth: Neuro-cognitive processing of garden-path jokes},

author = {Bastian Mayerhofer and Annekathrin Schacht},

doi = {10.3389/fpsyg.2015.00550},

year  = {2015},

date = {2015-01-01},

journal = {Frontiers in Psychology},

volume = {6},

pages = {550},

abstract = {In so-called garden-path jokes, an initial semantic representation is violated, and semantic revision reestablishes a coherent representation. 48 jokes were manipulated in three conditions: (i) a coherent ending, (ii) a joke ending, and (iii) a discourse-incoherent ending. A reading times study (N =24) and three studies with recordings of ERP and pupil changes (N = 21, 24, and 24, respectively) supported the hypothesized cognitive processes. Jokes showed increased reading times of the final word compared to coherent endings. ERP data mainly indicated semantic integration difficulties (N400). Larger pupil diameters to joke endings presumably reflect emotional responses. ERP evidence for increased discourse processing efforts and emotional responses, as assumed to be reflected in late left anterior negativity and LLAN modulations and an enhanced late frontal positivity (fP600), respectively, remains however incomplete. Processing of incoherent endings was also accompanied by increased reading times, a stronger and sustained N400, and context-sensitive P600 effects. Together, these findings provide evidence for a sequential, non-monotonic, and incremental discourse comprehension of garden-path jokes.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Metzner2015,

title = {Brain responses to world knowledge violations: A comparison of stimulus- and fixation-triggered event-related potentials and neural oscillations},

author = {Paul Metzner and Titus Malsburg and Shravan Vasishth and Frank Rösler},

doi = {10.1162/jocn_a_00731},

year  = {2015},

date = {2015-01-01},

journal = {Journal of Cognitive Neuroscience},

volume = {27},

number = {5},

pages = {1017–1028},

abstract = {Recent research has shown that brain potentials time-locked to fixations in natural reading can be similar to brain potentials recorded during rapid serial visual presentation (RSVP). We attempted two replications of Hagoort, Hald, Bastiaansen, and Petersson [Hagoort, P., Hald, L., Bastiaansen, M., & Petersson, K. M. Integration of word meaning and world knowledge in language comprehension. Science, 304, 438-441, 2004] to determine whether this correspondence also holds for oscillatory brain responses. Hagoort et al. reported an N400 effect and synchronization in the theta and gamma range following world knowledge violations. Our first experiment (n = 32) used RSVP and replicated both the N400 effect in the ERPs and the power increase in the theta range in the time-frequency domain. In the second experiment (n = 49), participants read the same materials freely while their eye movements and their EEG were monitored. First fixation durations, gaze durations, and regression rates were increased, and the ERP showed an N400 effect. An analysis of time-frequency representations showed synchronization in the delta range (1-3 Hz) and desynchronization in the upper alpha range (11-13 Hz) but no theta or gamma effects. The results suggest that oscillatory EEG changes elicited by world knowledge violations are different in natural reading and RSVP. This may reflect differences in how representations are constructed and retrieved from memory in the two presentation modes.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Andoh2015,

title = {Asymmetric interhemispheric transfer in the auditory network: Evidence from TMS, resting-state fMRI, and diffusion imaging},

author = {Jamila Andoh and Reiko Matsushita and Robert J. Zatorre},

doi = {10.1523/JNEUROSCI.2333-15.2015},

year  = {2015},

date = {2015-01-01},

journal = {Journal of Neuroscience},

volume = {43},

number = {43},

pages = {14602–14611},

abstract = {Hemispheric asymmetries in human auditory cortical function and structure are still highly debated. Brain stimulation approaches can complement correlational techniques by uncovering causal influences. Previous studies have shown asymmetrical effects of transcranial magnetic stimulation (TMS) on task performance, but it is unclear whether these effects are task-specific or reflect intrinsic network properties. To test how modulation of auditory cortex (AC) influences functional networks and whether this influence is asymmetrical, the present study measured resting-state fMRI connectivity networks in 17 healthy volunteers before and immediately after TMS (continuous theta burst stimulation) to the left or right AC, and the vertex as a control. We also examined the relationship between TMS-induced interhemispheric signal propagation and anatomical properties of callosal auditory fibers as measured with diffusion-weighted MRI. We found that TMS to the right AC, but not the left, resulted in widespread connectivity decreases in auditory- and motor-related networks in the resting state. Individual differences in the degree of change in functional connectivity between auditory cortices after TMS applied over the right AC were negatively related to the volume of callosal auditory fibers. The findings show that TMS-induced network modulation occurs, even in the absence of an explicit task, and that the magnitude of the effect differs across individuals as a function of callosal structure, supporting a role for the corpus callosum in mediating functional asymmetry. The findings support theoretical models emphasizing hemispheric differences in network organization and are of practical significance in showing that brain stimulation studies need to take network-level effects into account.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Cazzoli2015a,

title = {The role of the right posterior parietal cortex in letter migration between words},

author = {Dario Cazzoli and René M. Müri and Christopher Kennard and Clive R. Rosenthal},

year  = {2015},

date = {2015-01-01},

journal = {Journal of Cognitive Neuroscience},

volume = {27},

number = {2},

pages = {377–386},

abstract = {When briefly presented with pairs of words, skilled readers can sometimes report words with migrated letters (e.g., they report hunt when presented with the words hint and hurt). This and other letter migration phenomena have been often used to investigate factors that influence reading such as letter position coding. However, the neural basis of letter migration is poorly understood. Previous evidence has implicated the right posterior parietal cortex (PPC) in processing visuospatial attributes and lexical properties during word reading. The aim of this study was to assess this putative role by combining an inhibitory TMS protocol with a letter migration paradigm, which was designed to examine the contributions of visuospatial attributes and lexical factors. Temporary interference with the right PPC led to three specific effects on letter migration. First, the number of letter migrations was significantly increased only in the group with active stimulation (vs. a sham stimulation group or a control group without stimulation), and there was no significant effect on other error types. Second, this effect occurred only when letter migration could result in a meaningful word (migration vs. control context). Third, the effect of active stimulation on the number of letter migrations was lateralized to target words presented on the left. Our study thus demonstrates that the right PPC plays a specific and causal role in the phenomenon of letter migration. The nature of this role cannot be explained solely in terms of visuospatial attention, rather it involves an interplay between visuospatial attentional and word reading-specific factors.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Chechlacz2015,

title = {Structural organization of the corpus callosum predicts attentional shifts after continuous theta burst stimulation},

author = {Magdalena Chechlacz and Glyn W. Humphreys and Stamatios N. Sotiropoulos and Christopher Kennard and Dario Cazzoli},

doi = {10.1523/JNEUROSCI.2610-15.2015},

year  = {2015},

date = {2015-01-01},

journal = {Journal of Neuroscience},

volume = {35},

number = {46},

pages = {15353–15368},

abstract = {Repetitive transcranial magnetic stimulation (rTMS) applied over the right posterior parietal cortex (PPC) in healthy participants has been shown to trigger a significant rightward shift in the spatial allocation of visual attention, temporarily mimicking spatial deficits observed in neglect. In contrast, rTMS applied over the left PPC triggers a weaker or null attentional shift. However, large interindividual differences in responses to rTMS have been reported. Studies measuring changes in brain activation suggest that the effects of rTMS may depend on both interhemispheric and intrahemispheric interactions between cortical loci controlling visual attention. Here, we investigated whether variability in the structural organization of human white matter pathways subserving visual attention, as assessed by diffusion magnetic resonance imaging and tractography, could explain interindividual differences in the effects of rTMS. Most participants showed a rightward shift in the allocation of spatial attention after rTMS over the right intraparietal sulcus (IPS), but the size of this effect varied largely across participants. Conversely, rTMS over the left IPS resulted in strikingly opposed individual responses, with some participants responding with rightward and some with leftward attentional shifts. We demonstrate that microstructural and macrostructural variability within the corpus callosum, consistent with differential effects on cross-hemispheric interactions, predicts both the extent and the direction of the response to rTMS. Together, our findings suggest that the corpus callosum may have a dual inhibitory and excitatory function in maintaining the interhemispheric dynamics that underlie the allocation of spatial attention.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Graaf2015,

title = {Spatially specific vs. unspecific disruption of visual orientation perception using chronometric pre-stimulus TMS},

author = {Tom A. Graaf and Felix Duecker and Martin H. P. Fernholz and Alexander T. Sack},

doi = {10.3389/fnbeh.2015.00005},

year  = {2015},

date = {2015-01-01},

journal = {Frontiers in Behavioral Neuroscience},

volume = {9},

pages = {5},

abstract = {Transcranial magnetic stimulation (TMS) over occipital cortex can impair visual processing. Such ‘TMS masking' has repeatedly been shown at several stimulus onset asynchronies (SOAs), with TMS pulses generally applied after the onset of a visual stimulus. Following increased interest in the neuronal state-dependency of visual processing, we recently explored the efficacy of TMS at ‘negative SOAs', when no visual processing can yet occur. We could reveal pre-stimulus TMS disruption, with results moreover hinting at two separate mechanisms in occipital cortex biasing subsequent orientation perception. Here we extended this work, including a chronometric design to map the temporal dynamics of spatially specific and unspecific mechanisms of state-dependent visual processing, while moreover controlling for TMS-induced pupil covering. TMS pulses applied 60-40 ms prior to a visual stimulus decreased orientation processing independent of stimulus location, while a local suppressive effect was found for TMS applied 30-10 ms pre-stimulus. These results contribute to our understanding of spatiotemporal mechanisms in occipital cortex underlying the state-dependency of visual processing, providing a basis for future work to link pre-stimulus TMS suppression effects to other known visual biasing mechanisms.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Donaldson2015,

title = {Exploring associations between gaze patterns and putative human mirror neuron system activity},

author = {Peter H. Donaldson and Caroline T. Gurvich and Joanne Fielding and Peter G. Enticott},

doi = {10.3389/fnhum.2015.00523},

year  = {2015},

date = {2015-01-01},

journal = {Frontiers in Human Neuroscience},

volume = {9},

pages = {523},

abstract = {The human mirror neuron system (MNS) is hypothesized to be crucial to social cognition. Given that key MNS-input regions such as the superior temporal sulcus are involved in biological motion processing, and mirror neuron activity in monkeys has been shown to vary with visual attention, aberrant MNS function may be partly attributable to atypical visual input. To examine the relationship between gaze pattern and interpersonal motor resonance (IMR; an index of putative MNS activity), healthy right-handed participants aged 18–40 (n = 26) viewed videos of transitive grasping actions or static hands, whilst the left primary motor cortex received transcranial magnetic stimulation. Motor- evoked potentials recorded in contralateral hand muscles were used to determine IMR. Participants also underwent eyetracking analysis to assess gaze patterns whilst viewing the same videos. No relationship was observed between predictive gaze and IMR. However, IMR was positively associated with fixation counts in areas of biological motion in the videos, and negatively associated with object areas. These findings are discussed with reference to visual influences on the MNS, and the possibility that MNS atypicalities might be influenced by visual processes such as aberrant gaze pattern.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Malik2015,

title = {Role of early visual cortex in trans-saccadic memory of object features},

author = {Pankhuri Malik and Joost C. Dessing and J. Douglas Crawford},

year  = {2015},

date = {2015-01-01},

journal = {Journal of Vision},

volume = {15},

number = {7},

pages = {1–17},

abstract = {Early visual cortex (EVC) participates in visual feature memory and the updating of remembered locations across saccades, but its role in the trans-saccadic integration of object features is unknown. We hypothesized that if EVC is involved in updating object features relative to gaze, feature memory should be disrupted when saccades remap an object representation into a simultaneously perturbed EVC site. To test this, we applied transcranial magnetic stimulation (TMS) over functional magnetic resonance imaging–localized EVC clusters corresponding to the bottom left/right visual quadrants (VQs). During experiments, these VQs were probed psychophysically by briefly presenting a central object (Gabor patch) while subjects fixated gaze to the right or left (and above). After a short memory interval, participants were required to detect the relative change in orientation of a re-presented test object at the same spatial location. Participants either sustained fixation during the memory interval (fixation task)ormade a horizontal saccade that either maintained or reversed the VQ of the object (saccade task). Three TMS pulses (coinciding with the pre-, peri-, and postsaccade intervals) were applied to the left or right EVC. This had no effect when (a) fixation was maintained, (b) saccades kept the object in the same VQ, or (c) the EVC quadrant corresponding to the first object was stimulated. However, as predicted, TMS reduced performance when saccades (especially larger saccades) crossed the remembered object location and brought it into the VQ corresponding to the TMS site. This suppression effect was statistically significant for leftward saccades and followed a weaker trend for rightward saccades. These causal results are consistent with the idea that EVC is involved in the gaze-centered updating of object features for trans-saccadic memory and perception.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Marshall2015,

title = {Frontoparietal structural connectivity mediates the top-down control of neuronal synchronization associated with selective attention},

author = {Tom R. Marshall and Til Ole Bergmann and Ole Jensen},

doi = {10.1371/journal.pbio.1002272},

year  = {2015},

date = {2015-01-01},

journal = {PLoS Biology},

volume = {13},

number = {10},

pages = {e1002272},

abstract = {Neuronal synchronization reflected by oscillatory brain activity has been strongly implicated in the mechanisms supporting selective gating. We here aimed at identifying the anatomical pathways in humans supporting the top-down control of neuronal synchronization. We first collected diffusion imaging data using magnetic resonance imaging to identify the medial branch of the superior longitudinal fasciculus (SLF), a white-matter tract connecting frontal control areas to parietal regions. We then quantified the modulations in oscillatory activity using magnetoencephalography in the same subjects performing a spatial attention task. We found that subjects with a stronger SLF volume in the right compared to the left hemi- sphere (or vice versa) also were the subjects who had a better ability to modulate right com- pared to left hemisphere alpha and gamma band synchronization, with the latter also predicting biases in reaction time. Our findings implicate the medial branch of the SLF in mediating top-down control of neuronal synchronization in sensory regions that support selective attention.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Vetter2015,

title = {TMS over V5 disrupts motion prediction},

author = {Petra Vetter and Marie-Hélène Grosbras and Lars Muckli},

doi = {10.1093/cercor/bht297},

year  = {2015},

date = {2015-01-01},

journal = {Cerebral Cortex},

volume = {25},

number = {4},

pages = {1052–1059},

abstract = {Given the vast amount of sensory information the brain has to deal with, predicting some of this information based on the current context is a resource-efficient strategy. The framework of predictive coding states that higher-level brain areas generate a predictive model to be communicated via feedback connections to early sensory areas. Here, we directly tested the necessity of a higher-level visual area, V5, in this predictive processing in the context of an apparent motion paradigm. We flashed targets on the apparent motion trace in-time or out-of-time with the predicted illusory motion token. As in previous studies, we found that predictable in-time targets were better detected than unpredictable out-of-time targets. However, when we applied functional magnetic resonance imaging-guided, double-pulse transcranial magnetic stimulation (TMS) over left V5 at 13-53 ms before target onset, the detection advantage of in-time targets was eliminated; this was not the case when TMS was applied over the vertex. Our results are causal evidence that V5 is necessary for a prediction effect, which has been shown to modulate V1 activity (Alink et al. 2010). Thus, our findings suggest that information processing between V5 and V1 is crucial for visual motion prediction, providing experimental support for the predictive coding framework.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Zenon2015,

title = {Disrupting the supplementary motor area makes physical effort appear less effortful},

author = {Alexandre Zenon and Mariam Sidibe and Etienne Olivier},

doi = {10.1523/JNEUROSCI.3789-14.2015},

year  = {2015},

date = {2015-01-01},

journal = {Journal of Neuroscience},

volume = {35},

number = {23},

pages = {8737–8744},

abstract = {The perception of physical effort is relatively unaffected by the suppression of sensory afferences, indicating that this function relies mostly on the processing of the central motor command. Neural signals in the supplementary motor area (SMA) correlate with the intensity of effort, suggesting that the motor signal involved in effort perception could originate from this area, but experimental evidence supporting this view is still lacking. Here, we tested this hypothesis by disrupting neural activity in SMA, in primary motor cortex (M1), or in a control site by means of continuous theta-burst transcranial magnetic stimulation, while measuring effort perception during grip forces of different intensities. After each grip force exertion, participants had the opportunity to either accept or refuse to replicate the same effort for varying amounts of reward. In addition to the subjective rating of perceived exertion, effort perception was estimated on the basis of the acceptance rate, the effort replication accuracy, the influence of the effort exerted in trial t on trial t+1, and pupil dilation. We found that disruption of SMA activity, but not of M1, led to a consistent decrease in effort perception, whatever the measure used to assess it. Accordingly, we modeled effort perception in a structural equation model and found that only SMA disruption led to a significant alteration of effort perception. These findings indicate that effort perception relies on the processing of a signal originating from motor-related neural circuits upstream of M1 and that SMA is a key node of this network.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Auksztulewicz2015,

title = {Attentional enhancement of auditory mismatch responses: A DCM/MEG study},

author = {Ryszard Auksztulewicz and Karl J. Friston},

doi = {10.1093/cercor/bhu323},

year  = {2015},

date = {2015-01-01},

journal = {Cerebral Cortex},

volume = {25},

number = {11},

pages = {4273–4283},

abstract = {Despite similar behavioral effects, attention and expectation influence evoked responses differently: Attention typically enhances event-related responses, whereas expectation reduces them. This dissociation has been reconciled under predictive coding, where prediction errors are weighted by precision associated with attentional modulation. Here, we tested the predictive coding account of attention and expectation using magnetoencephalography and modeling. Temporal attention and sensory expectation were orthogonally manipulated in an auditory mismatch paradigm, revealing opposing effects on evoked response amplitude. Mismatch negativity (MMN) was enhanced by attention, speaking against its supposedly pre-attentive nature. This interaction effect was modeled in a canonical microcircuit using dynamic causal modeling, comparing models with modulation of extrinsic and intrinsic connectivity at different levels of the auditory hierarchy. While MMN was explained by recursive interplay of sensory predictions and prediction errors, attention was linked to the gain of inhibitory interneurons, consistent with its modulation of sensory precision.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Bach2015,

title = {Sustained magnetic responses in temporal cortex reflect instantaneous significance of approaching and receding sounds},

author = {Dominik R. Bach and Nicholas Furl and Gareth Barnes and Raymond J. Dolan},

doi = {10.1371/journal.pone.0134060},

year  = {2015},

date = {2015-01-01},

journal = {PLoS ONE},

volume = {10},

number = {7},

pages = {e0134060},

abstract = {Rising sound intensity often signals an approaching sound source and can serve as a powerful warning cue, eliciting phasic attention, perception biases and emotional responses. How the evaluation of approaching sounds unfolds over time remains elusive. Here, we capitalised on the temporal resolution of magnetoencephalograpy (MEG) to investigate in humans a dynamic encoding of perceiving approaching and receding sounds. We compared magnetic responses to intensity envelopes of complex sounds to those of white noise sounds, in which intensity change is not perceived as approaching. Sustained magnetic fields over temporal sensors tracked intensity change in complex sounds in an approximately linear fashion, an effect not seen for intensity change in white noise sounds, or for overall intensity. Hence, these fields are likely to track approach/recession, but not the apparent (instantaneous) distance of the sound source, or its intensity as such. As a likely source of this activity, the bilateral inferior temporal gyrus and right temporo-parietal junction emerged. Our results indicate that discrete temporal cortical areas parametrically encode behavioural significance in moving sound sources where the signal unfolded in a manner reminiscent of evidence accumulation. This may help an understanding of how acoustic percepts are evaluated as behaviourally relevant, where our results highlight a crucial role of cortical areas.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Banerjee2015,

title = {Interests shape how adolescents pay attention: The interaction of motivation and top-down attentional processes in biasing sensory activations to anticipated events},

author = {Snigdha Banerjee and Hans Peter Frey and Sophie Molholm and John J. Foxe},

doi = {10.1111/ejn.12810},

year  = {2015},

date = {2015-01-01},

journal = {European Journal of Neuroscience},

volume = {41},

number = {6},

pages = {818–834},

abstract = {The voluntary allocation of attention to environmental inputs is a crucial mechanism of healthy cognitive functioning, and is probably influenced by an observer's level of interest in a stimulus. For example, an individual who is passionate about soccer but bored by botany will obviously be more attentive at a soccer match than an orchid show. The influence of monetary rewards on attention has been examined, but the impact of more common motivating factors (i.e. the level of interest in the materials under observation) remains unclear, especially during development. Here, stimulus sets were designed based on survey measures of the level of interest of adolescent participants in several item classes. High-density electroencephalography was recorded during a cued spatial attention task in which stimuli of high or low interest were presented in separate blocks. The motivational impact on performance of a spatial attention task was assessed, along with event-related potential measures of anticipatory top-down attention. As predicted, performance was improved for the spatial target detection of high interest items. Further, the impact of motivation was observed in parieto-occipital processes associated with anticipatory top-down spatial attention. The anticipatory activity over these regions was also increased for high vs. low interest stimuli, irrespective of the direction of spatial attention. The results also showed stronger anticipatory attentional and motivational modulations over the right vs. left parieto-occipital cortex. These data suggest that motivation enhances top-down attentional processes, and can independently shape activations in sensory regions in anticipation of events. They also suggest that attentional functions across hemispheres may not fully mature until late adolescence.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Bays2015,

title = {Alpha-band EEG activity in perceptual learning},

author = {Brett C. Bays and Kristina M. Visscher and Christophe C. Le Dantec and Aaron R. Seitz},

doi = {10.1167/15.10.7},

year  = {2015},

date = {2015-01-01},

journal = {Journal of Vision},

volume = {15},

number = {10},

pages = {1–12},

abstract = {In studies of perceptual learning (PL), subjects are typically highly trained across many sessions to achieve perceptual benefits on the stimuli in those tasks. There is currently significant debate regarding what sources of brain plasticity underlie these PL-based learning improvements. Here we investigate the hypothesis that PL, among other mechanisms, leads to task automaticity, especially in the presence of the trained stimuli. To investigate this hypothesis, we trained participants for eight sessions to find an oriented target in a field of near-oriented distractors and examined alpha-band activity, which modulates with attention to visual stimuli, as a possible measure of automaticity. Alpha-band activity was acquired via electroencephalogram (EEG), before and after training, as participants performed the task with trained and untrained stimuli. Results show that participants underwent significant learning in this task (as assessed by threshold, accuracy, and reaction time improvements) and that alpha power increased during the pre-stimulus period and then underwent greater desynchronization at the time of stimulus presentation following training. However, these changes in alpha-band activity were not specific to the trained stimuli, with similar patterns of posttraining alpha power for trained and untrained stimuli. These data are consistent with the view that participants were more efficient at focusing resources at the time of stimulus presentation and are consistent with a greater automaticity of task performance. These findings have implications for PL, as transfer effects from trained to untrained stimuli may partially depend on differential effort of the individual at the time of stimulus processing.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Wyart2015,

title = {Neural mechanisms of human perceptual choice under focused and divided attention},

author = {Valentin Wyart and Nicholas E. Myers and Christopher Summerfield},

doi = {10.1523/JNEUROSCI.3276-14.2015},

year  = {2015},

date = {2015-01-01},

journal = {Journal of Neuroscience},

volume = {35},

number = {8},

pages = {3485–3498},

abstract = {Perceptual decisions occur after the evaluation and integration of momentary sensory inputs, and dividing attention between spatially disparate sources of information impairs decision performance. However, it remains unknown whether dividing attention degrades the precision of sensory signals, precludes their conversion into decision signals, or dampens the integration of decision information toward an appropriate response. Here we recorded human electroencephalographic (EEG) activity while participants categorized one of two simultaneous and independent streams of visual gratings according to their average tilt. By analyzing trial-by-trial correlations between EEG activity and the information offered by each sample, we obtained converging behavioral and neural evidence that dividing attention between left and right visual fields does not dampen the encoding of sensory or decision information. Under divided attention, momentary decision information from both visual streams was encoded in slow parietal signals without interference but was lost downstream during their integration as reflected in motor mu- and beta-band (10-30 Hz) signals, resulting in a "leaky" accumulation process that conferred greater behavioral influence to more recent samples. By contrast, sensory inputs that were explicitly cued as irrelevant were not converted into decision signals. These findings reveal that a late cognitive bottleneck on information integration limits decision performance under divided attention, and places new capacity constraints on decision-theoretic models of information integration under cognitive load.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Yang2015,

title = {EEG activity during movement planning encodes upcoming peak speed and acceleration and improves the accuracy in predicting hand kinematics},

author = {Lingling Yang and Howard Leung and Markus Plank and Joe Snider and Howard Poizner},

doi = {10.1109/JBHI.2014.2327635},

year  = {2015},

date = {2015-01-01},

journal = {IEEE Journal of Biomedical and Health Informatics},

volume = {19},

number = {1},

pages = {22–28},

abstract = {The relationship between movement kinematics and human brain activity is an important and fundamental question for the development of neural prosthesis. The peak velocity and the peak acceleration could best reflect the feedforward-type movement thus it is worthwhile to investigate them further. Most related studies focused on the correlation between kinematics and brain activity during the movement execution or imagery. However, human movement is the result of the motor planning phase as well as the execution phase and researchers have demonstrated that statistical correlations exist between EEG activity during the motor planning and the peak velocity and the peak acceleration using grand-average analysis. In this paper, we examined whether the correlations were concealed in trial-to-trial decoding from the low signal-to-noise ratio of EEG activity. The alpha and beta powers from the movement planning phase were combined with the alpha and beta powers from the movement execution phase to predict the peak tangential speed and acceleration. The results showed that EEG activity from the motor planning phase could also predict the peak speed and the peak acceleration with a reasonable accuracy. Furthermore, the decoding accuracy of the peak speed and the peak acceleration could both be improved by combining band powers from the motor planning phase with the band powers from the movement execution.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Simola2015,

title = {Affective processing in natural scene viewing: Valence and arousal interactions in eye-fixation-related potentials},

author = {Jaana Simola and Kevin Le Fevre and Jari Torniainen and Thierry Baccino},

doi = {10.1016/j.neuroimage.2014.11.030},

year  = {2015},

date = {2015-01-01},

journal = {NeuroImage},

volume = {106},

pages = {21–33},

publisher = {Elsevier Inc.},

abstract = {Attention is drawn to emotionally salient stimuli. The present study investigates processing of emotionally salient regions during free viewing of emotional scenes that were categorized according to the two-dimensional model comprising of valence (unpleasant, pleasant) and arousal (high, low). Recent studies have reported interactions between these dimensions, indicative of stimulus-evoked approach or withdrawal tendencies. We addressed the valence and arousal effects when emotional items were embedded in complex real-world scenes by analyzing both eye movement behavior and eye-fixation-related potentials (EFRPs) time-locked to the critical event of fixating the emotionally salient items for the first time. Both data sets showed an interaction between the valence and arousal dimensions. First, the fixation rates and gaze durations on emotionally salient regions were enhanced for unpleasant versus pleasant images in the high arousal condition. In the low arousal condition, both measures were enhanced for pleasant versus unpleasant images. Second, the EFRP results at 140-170. ms [P2] over the central site showed stronger responses for high versus low arousing images in the unpleasant condition. In addition, the parietal LPP responses at 400-500. ms post-fixation were enhanced for stimuli reflecting congruent stimulus dimensions, that is, stronger responses for high versus low arousing images in the unpleasant condition and stronger responses for low versus high arousing images in the pleasant condition. The present findings support the interactive two-dimensional approach, according to which the integration of valence and arousal recruits brain regions associated with action tendencies of approach or withdrawal.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Snyder2015a,

title = {Global network influences on local functional connectivity},

author = {Adam C. Snyder and Michael J. Morais and Cory M. Willis and Matthew A. Smith},

doi = {10.1038/nn.3979},

year  = {2015},

date = {2015-01-01},

journal = {Nature Neuroscience},

volume = {18},

number = {5},

pages = {736–743},

abstract = {A central neuroscientific pursuit is understanding neuronal interactions that support computations underlying cognition and behavior. Although neurons interact across disparate scales, from cortical columns to whole-brain networks, research has been restricted to one scale at a time. We measured local interactions through multi-neuronal recordings while accessing global networks using scalp electroencephalography (EEG) in rhesus macaques. We measured spike count correlation, an index of functional connectivity with computational relevance, and EEG oscillations, which have been linked to various cognitive functions. We found a non-monotonic relationship between EEG oscillation amplitude and spike count correlation, contrary to the intuitive expectation of a direct relationship. With a widely used network model, we replicated these findings by incorporating a private signal targeting inhibitory neurons, a common mechanism proposed for gain modulation. Finally, we found that spike count correlation explained nonlinearities in the relationship between EEG oscillations and response time in a spatial selective attention task.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Snyder2015,

title = {Stimulus-dependent spiking relationships with the EEG},

author = {Adam C. Snyder and Matthew A. Smith},

doi = {10.1007/s12063-018-0133-z},

year  = {2015},

date = {2015-01-01},

journal = {Journal of Neurophysiology},

volume = {114},

number = {3},

pages = {1468–1482},

abstract = {The development and refinement of noninvasive techniques for imaging neural activity is of paramount importance for human neuroscience. Currently, the most accessible and popular technique is electroencephalography (EEG). However, nearly all of what we know about the neural events that underlie EEG signals is based on inference, because of the dearth of studies that have simultaneously paired EEG recordings with direct recordings of single neurons. From the perspective of electrophysiologists there is growing interest in understanding how spiking activ- ity coordinates with large-scale cortical networks. Evidence from recordings at both scales highlights that sensory neurons operate in very distinct states during spontaneous and visually evoked activity, which appear to form extremes in a continuum of coordination in neural networks. We hypothesized that individual neurons have idio- syncratic relationships to large-scale network activity indexed by EEG signals, owing to the neurons' distinct computational roles within the local circuitry. We tested this by recording neuronal populations in visual area V4 of rhesus macaques while we simultaneously recorded EEG. We found substantial heterogeneity in the timing and strength of spike-EEG relationships and that these relationships became more diverse during visual stimulation compared with the spontaneous state. The visual stimulus apparently shifts V4 neurons from a state in which they are relatively uniformly embedded in large-scale network activity to a state in which their distinct roles within the local population are more prominent, suggesting that the specific way in which individual neurons relate to EEG signals may hold clues regarding their computational roles.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Tan2015,

title = {MEG-measured auditory steady-state oscillations show high test-retest reliability: A sensor and source-space analysis},

author = {Heng Ru May Tan and Joachim Gross and P. J. Uhlhaas},

doi = {10.1016/j.neuroimage.2015.07.055},

year  = {2015},

date = {2015-01-01},

journal = {NeuroImage},

volume = {122},

pages = {417–426},

publisher = {The Authors},

abstract = {Stability of oscillatory signatures across magnetoencephalography (MEG) measurements is an important prerequisite for basic and clinical research that has been insufficiently addressed. Here, we evaluated the test-retest reliability of auditory steady-state responses (ASSRs) over two MEG sessions. The study required participants (N. = 13) to detect the rare occurrence of pure tones interspersed within a stream of 5. Hz or 40. Hz amplitude-modulated (AM) tones. Intraclass correlations (ICC; Shrout and Fleiss, 1979) were derived to assess stability of spectral power changes and the inter-trial phase coherence (ITPC) of task-elicited neural responses. ASSRs source activity was estimated using eLORETA beamforming from bilateral auditory cortex. ASSRs to 40. Hz AM stimuli evoked stronger power modulation and phase-locking than 5. Hz stimulation. Overall, spectral power and ITPC values at both sensor- and source-level showed robust ICC values. Notably, ITPC measures yielded higher ICCs (~. 0.86-0.96) between sessions compared to the assessment of spectral power change (~. 0.61-0.82). Our data indicate that spectral modulations and phase consistency of ASSRs in MEG data are highly reproducible, providing support for MEG-measured oscillatory parameters in basic and clinical research.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Wassenhove2015,

title = {Visual-induced expectations modulate auditory cortical responses},

author = {Virginie Wassenhove and Lukasz Grzeczkowski},

doi = {10.3389/fnins.2015.00011},

year  = {2015},

date = {2015-01-01},

journal = {Frontiers in Neuroscience},

volume = {9},

pages = {11},

abstract = {Active sensing has important consequences on multisensory processing (Schroeder et al., 2010). Here, we asked whether in the absence of saccades, the position of the eyes and the timing of transient color changes of visual stimuli could selectively affect the excitability of auditory cortex by predicting the "where" and the "when" of a sound, respectively. Human participants were recorded with magnetoencephalography (MEG) while maintaining the position of their eyes on the left, right, or center of the screen. Participants counted color changes of the fixation cross while neglecting sounds which could be presented to the left, right, or both ears. First, clear alpha power increases were observed in auditory cortices, consistent with participants' attention directed to visual inputs. Second, color changes elicited robust modulations of auditory cortex responses ("when" prediction) seen as ramping activity, early alpha phase-locked responses, and enhanced high-gamma band responses in the contralateral side of sound presentation. Third, no modulations of auditory evoked or oscillatory activity were found to be specific to eye position. Altogether, our results suggest that visual transience can automatically elicit a prediction of "when" a sound will occur by changing the excitability of auditory cortices irrespective of the attended modality, eye position or spatial congruency of auditory and visual events. To the contrary, auditory cortical responses were not significantly affected by eye position suggesting that "where" predictions may require active sensing or saccadic reset to modulate auditory cortex responses, notably in the absence of spatial orientation to sounds.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Vanegas2015,

title = {Electrophysiological indices of surround suppression in humans},

author = {M. Isabel Vanegas and Annabelle Blangero and Simon P. Kelly},

doi = {10.1152/jn.00774.2014},

year  = {2015},

date = {2015-01-01},

journal = {Journal of Neurophysiology},

volume = {113},

number = {4},

pages = {1100–1109},

abstract = {Surround suppression is a well-known example of contextual interaction in visual cortical neurophysiology, whereby the neural response to a stimulus presented within a neuron's classical receptive field is suppressed by surrounding stimuli. Human psychophysical reports present an obvious analog to the effects seen at the single-neuron level: stimuli are perceived as lower-contrast when embedded in a surround. Here we report on a visual paradigm that provides relatively direct, straightforward indices of surround suppression in human electrophysiology, enabling us to reproduce several well-known neurophysiological and psychophysical effects, and to conduct new analyses of temporal trends and retinal location effects. Steady-state visual evoked potentials (SSVEP) elicited by flickering “foreground” stimuli were measured in the context of various static surround patterns. Early visual cortex geometry and retinotopic organization were exploited to enhance SSVEP amplitude. The foreground response was strongly suppressed as a monotonic function of surround contrast. Further- more, suppression was stronger for surrounds of matching orientation than orthogonally-oriented ones, and stronger at peripheral than foveal locations. These patterns were reproduced in psychophysical reports of perceived contrast, and peripheral electrophysiological suppression effects correlated with psychophysical effects across subjects. Temporal analysis of SSVEP amplitude revealed short-term contrast adaptation effects that caused the foreground signal to either fall or grow over time, depending on the relative contrast of the surround, consistent with stronger adaptation of the suppressive drive. This electrophysiology paradigm has clinical potential in indexing not just visual deficits but possibly gain control deficits expressed more widely in the disordered brain.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Wallis2015a,

title = {Frontoparietal and cingulo-opercular networks play dissociable roles in control of working memory},

author = {George Wallis and Mark Stokes and Helena Cousijn and Mark W. Woolrich and Anna C. Nobre},

year  = {2015},

date = {2015-01-01},

journal = {Journal of Cognitive Neuroscience},

volume = {27},

pages = {2019–2034},

abstract = {We used magnetoencephalography to characterize the spatiotemporal dynamics of cortical activity during top–down control of working memory (WM). fMRI studies have previously implicated both the frontoparietal and cingulo-opercular networks in control over WM, but their respective contributions are unclear. In our task, spatial cues indicating the relevant item in a WM array occurred either before the memory array or during the maintenance period, providing a direct comparison between prospective and retrospective control of WM. We found that in both cases a frontoparietal network activated following the cue, but following retrocues this activation was transient and was succeeded by a cinguloopercular network activation. We also characterized the time course of top–down modulation of alpha activity in visual/parietal cortex. This modulation was transient following retrocues, occurring in parallel with the frontoparietal network activation. We suggest that the frontoparietal network is responsible for top–down modulation of activity in sensory cortex during both preparatory attention and orienting within memory. In contrast, the cinguloopercular network plays a more downstream role in cognitive control, perhaps associated with output gating of memory},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Weiler2015,

title = {The unidirectional prosaccade switch-cost: Electroencephalographic evidence of task-set inertia in oculomotor control},

author = {Jeffrey Weiler and Cameron D. Hassall and Olave E. Krigolson and Matthew Heath},

doi = {10.1016/j.bbr.2014.10.012},

year  = {2015},

date = {2015-01-01},

journal = {Behavioural Brain Research},

volume = {278},

pages = {323–329},

publisher = {Elsevier B.V.},

abstract = {The execution of an antisaccade selectively increases the reaction time (RT) of a subsequent prosaccade (the unidirectional prosaccade switch-cost). To explain this finding, the task-set inertia hypothesis asserts that an antisaccade requires a cognitively mediated non-standard task-set that persists inertially and delays the planning of a subsequent prosaccade. The present study sought to directly test the theoretical tenets of the task-set inertia hypothesis by examining the concurrent behavioural and the event-related brain potential (ERP) data associated with the unidirectional prosaccade switch-cost. Participants pseudo-randomly alternated between pro- and antisaccades while electroencephalography (EEG) data were recorded. As expected, the completion of an antisaccade selectively increased the RT of a subsequent prosaccade, whereas the converse switch did not influence RTs. Thus, the behavioural results demonstrated the unidirectional prosaccade switch-cost. In terms of the ERP findings, we observed a reliable change in the amplitude of the P3 - time-locked to task-instructions - when trials were switched from a prosaccade to an antisaccade; however, no reliable change was observed when switching from an antisaccade to a prosaccade. This is a salient finding because extensive work has shown that the P3 provides a neural index of the task-set required to execute a to-be-completed response. As such, results showing that prosaccades completed after antisaccades exhibited increased RTs in combination with a P3 amplitude comparable to antisaccades provides convergent evidence that the unidirectional prosaccade switch-cost is attributed to the persistent activation of a non-standard antisaccade task-set.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Gergelyfi2015,

title = {Dissociation between mental fatigue and motivational state during prolonged mental activity},

author = {Mónika Gergelyfi and Benvenuto Jacob and Etienne Olivier and Alexandre Zénon},

doi = {10.3389/fnbeh.2015.00176},

year  = {2015},

date = {2015-01-01},

journal = {Frontiers in Behavioral Neuroscience},

volume = {9},

pages = {176},

abstract = {Mental fatigue (MF) is commonly observed following prolonged cognitive activity and can have major repercussions on the daily life of patients as well as healthy individuals. Despite its important impact, the cognitive processes involved in MF remain largely unknown. An influential hypothesis states that MF does not arise from a disruption of overused neural processes but, rather, is caused by a progressive decrease in motivation-related task engagement. Here, to test this hypothesis, we measured various neural, autonomic, psychometric and behavioral signatures of MF and motivation (EEG, ECG, pupil size, eye blinks, Skin conductance responses (SCRs), questionnaires and performance in a working memory (WM) task) in healthy volunteers, while MF was induced by Sudoku tasks performed for 120 min. Moreover extrinsic motivation was manipulated by using different levels of monetary reward. We found that, during the course of the experiment, the participants' subjective feeling of fatigue increased and their performance worsened while their blink rate and heart rate variability (HRV) increased. Conversely, reward-induced EEG, pupillometric and skin conductance signal changes, regarded as indicators of task engagement, remained constant during the experiment, and failed to correlate with the indices of MF. In addition, MF did not affect a simple reaction time task, despite the strong influence of extrinsic motivation on this task. Finally, alterations of the motivational state through monetary incentives failed to compensate the effects of MF. These findings indicate that MF in healthy subjects is not caused by an alteration of task engagement but is likely to be the consequence of a decrease in the efficiency, or availability, of cognitive resources.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Gutteling2015,

title = {Parallax-sensitive remapping of visual space in occipito-parietal alpha-band activity during whole-body motion},

author = {Tjerk P. Gutteling and Luc P. J. Selen and W. Pieter Medendorp},

year  = {2015},

date = {2015-01-01},

journal = {Journal of Neurophysiology},

volume = {113},

pages = {1574–1584},

abstract = {Despite the constantly changing retinal image due to eye, head, and body movements, we are able to maintain a stable representation of the visual environment. Various studies on retinal image shifts caused by saccades have suggested that occipital and parietal areas correct for these perturbations by a gaze-centered remapping of the neural image. However, such a uniform, rotational, remapping mechanism cannot work during translations when objects shift on the retina in a more complex, depth-dependent fashion due to motion parallax. Here we tested whether the brain's activity patterns show parallax-sensitive remapping of remembered visual space during whole-body motion. Under continuous recording of electroencephalography (EEG), we passively translated human subjects while they had to remember the location of a world-fixed visual target, briefly presented in front of or behind the eyes' fixation point prior to the motion. Using a psychometric approach we assessed the quality of the memory update, which had to be made based on vestibular feedback and other extraretinal motion cues. All subjects showed a variable amount of parallax-sensitive updating errors, i.e., the direction of the errors depended on the depth of the target relative to fixation. The EEG recordings show a neural correlate of this parallax-sensitive remapping in the alpha-band power at occipito-parietal electrodes. At parietal electrodes, the strength of these alpha-band modulations correlated significantly with updating performance. These results suggest that alpha-band oscillatory activity reflects the time-varying updating of gaze-centered spatial information during parallax-sensitive remapping during whole-body motion.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{He2015a,

title = {Face processing in the brains of pre-school aged children measured with MEG},

author = {Wei He and Jon Brock and Blake W. Johnson},

doi = {10.1016/j.neuroimage.2014.11.029},

year  = {2015},

date = {2015-01-01},

journal = {NeuroImage},

volume = {106},

pages = {317–327},

publisher = {Elsevier Inc.},

abstract = {There are two competing theories concerning the development of face perception: a late maturation account and an early maturation account. Magnetoencephalography (MEG) neuroimaging holds promise for adjudicating between the two opposing accounts by providing objective neurophysiological measures of face processing, with sufficient temporal resolution to isolate face-specific brain responses from those associated with other sensory, cognitive and motor processes. The current study used a customized child MEG system to measure M100 and M170 brain responses in 15 children aged three to six years while they viewed faces, cars and their phase-scrambled counterparts. Compared to adults tested using the same stimuli in a conventional MEG system, children showed significantly larger and later M100 responses. Children's M170 responses, derived by subtracting the responses to phase-scrambled images from the corresponding images (faces or cars) were delayed in latency but otherwise resembled the adult M170. This component has not been obtained in previous studies of young children tested using conventional adult MEG systems. However children did show a markedly reduced M170 response to cars in comparison to adults. This may reflect children's lack of expertise with cars relative to faces. Taken together, these data are in accord with recent behavioural and neuroimaging data that support early maturation of the basic face processing functions.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{He2015b,

title = {Development of effective connectivity in the core network for face perception},

author = {Wei He and Marta I. Garrido and Paul F. Sowman and Jon Brock and Blake W. Johnson},

doi = {10.1002/hbm.22762},

year  = {2015},

date = {2015-01-01},

journal = {Human Brain Mapping},

volume = {36},

number = {6},

pages = {2161–2173},

abstract = {This study measured effective connectivity within the core face network in young children using a paediatric magnetoencephalograph (MEG). Dynamic casual modeling (DCM) of brain responses was performed in a group of adults (N = 14) and a group of young children aged from 3 to 6 years (N = 15). Three candidate DCM models were tested, and the fits of the MEG data to the three models were compared at both individual and group levels. The results show that the connectivity structure of the core face network differs significantly between adults and children. Further, the relative strengths of face network connections were differentially modulated by experimental conditions in the two groups. These results support the interpretation that the core face network undergoes significant structural configuration and functional specialization between four years of age and adulthood.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Horschig2015,

title = {Modulation of posterior alpha activity by spatial attention allows for controlling a continuous brain–computer interface},

author = {Jörn M. Horschig and Wouter Oosterheert and Robert Oostenveld and Ole Jensen},

doi = {10.1007/s10548-014-0401-7},

year  = {2015},

date = {2015-01-01},

journal = {Brain Topography},

volume = {28},

number = {6},

pages = {852–864},

abstract = {Here we report that the modulation of alpha activity by covert attention can be used as a control signal in an online brain-computer interface, that it is reliable, and that it is robust. Subjects were instructed to orient covert visual attention to the left or right hemifield. We decoded the direction of attention from the magnetoencephalogram by a template matching classifier and provided the classification outcome to the subject in real-time using a novel graphical user interface. Training data for the templates were obtained from a Posner-cueing task conducted just before the BCI task. Eleven subjects participated in four sessions each. Eight of the subjects achieved classification rates significantly above chance level. Subjects were able to significantly increase their performance from the first to the second session. Individual patterns of posterior alpha power remained stable throughout the four sessions and did not change with increased performance. We conclude that posterior alpha power can successfully be used as a control signal in brain-computer interfaces. We also discuss several ideas for further improving the setup and propose future research based on solid hypotheses about behavioral consequences of modulating neuronal oscillations by brain computer interfacing.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Myers2015,

title = {Testing sensory evidence against mnemonic templates},

author = {Nicholas E. Myers and Gustavo Rohenkohl and Valentin Wyart and Mark W. Woolrich and Anna C. Nobre and Mark G. Stokes},

doi = {10.7554/eLife.09000.001},

year  = {2015},

date = {2015-01-01},

journal = {eLife},

volume = {4},

pages = {1–25},

abstract = {Most perceptual decisions require comparisons between current input and an internal template. Classic studies propose that templates are encoded in sustained activity of sensory neurons. However, stimulus encoding is itself dynamic, tracing a complex trajectory through activity space. Which part of this trajectory is pre-activated to reflect the template? Here we recorded magneto- and electroencephalography during a visual target-detection task, and used pattern analyses to decode template, stimulus, and decision-variable representation. Our findings ran counter to the dominant model of sustained pre-activation. Instead, template information emerged transiently around stimulus onset and quickly subsided. Cross-generalization between stimulus and template coding, indicating a shared neural representation, occurred only briefly. Our results are compatible with the proposal that template representation relies on a matched filter, transforming input into task-appropriate output. This proposal was consistent with a signed difference response at the perceptual decision stage, which can be explained by a simple neural model.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}