Clinical and Oculomotor Eye-Tracking Publications
EyeLink eye tracker clinical and oculomotor research publications up until 2025 (with some early 2026s) are listed below by year. You can search the eye-tracking publications using keywords such as Saccadic Adaptation, Schizophrenia, Nystagmus, etc. You can also search for individual author names, and limit searches by year (choose the year then click the search button). If we missed any EyeLink clinical or oculomotor articles, please email us!
2025 |
Gernot Horstmann Eye movements during gaze perception Journal Article In: Journal of vision, vol. 25, no. 12, pp. 1–17, 2025. @article{Horstmann2025,The gaze of other people is of interest to human observers, particularly in cases of direct gaze, that is, when it targets the observer. Gaze direction research has successfully clarified some of the mechanisms underlying gaze perception, but little is known about the active perception of direct gaze. Three eye-tracking experiments were conducted in which fixations and scan paths were recorded during the task to judge direct gaze. Somewhat surprisingly, judgments were issued after a single eye fixation only in a minority of trials. In most cases, observers fixated both eyes of a looker model, sometimes even scanning them repeatedly. Fixation duration showed a consistent pattern, where first fixations were longer when the task response followed immediately, and second fixations were shorter just before the response. A direct-gaze bias was tested but was not found: visiting the second eye was even more likely when the first fixation was on a straight-gazing rather than an averted eye. There was no systematic pattern in the final fixation, contradicting the expectation that it would fall on the abducting (leading) eye. It is argued that overt looking behavior during direct gaze judgments reflects a cumulative decision process that spans over consecutive fixations. Several factors may contribute to the high incidence of multiple-eye scans, including vergence and angle kappa. Vergence, in particular, is considered an important candidate, because the depth of fixation is ambiguous when only one eye is visible, but can be limited by probing the gaze direction of both eyes. |
A. Katanska; E. Krasta; A. Klavinska; S. Fomins; I. Ceple; R. Truksa Eye tracking applications in colour vision assessment Journal Article In: Latvian Journal of Physics and Technical Sciences, vol. 62, no. 5, pp. 46–57, 2025. @article{Katanska2025,Traditionally, colour vision assessment relies on the patient's subjective response. The current study introduces an objective approach using eye movement analysis to explore the perception of moving chromatic stimuli. Chromatic sensitivity was assessed using Dynamic-Static Colour Vision Test (DSCVT) stimuli. A total of 20 (15 female and 5 male) participants (aged 18–28 years, 21.7 ± 2.2) were recruited for the study. During stimulus presentation, participants were instructed to focus on the chromatic stimuli and provide a subjective response at the end of the demonstration. Simultaneously, eye gaze coordinates were recorded to assess chromatic sensitivity objectively. Sensory thresholds were determined using the method of constant stimuli, with detection probabilities computed through psychometric function fitting. Smooth pursuit eye movements were analysed using algorithms developed by Larsson et al. [1] and Nyström et al. [2], enabling the objective identification of the direction in which tracking distance was the longest. Higher chromatic saturation increased smooth pursuit detection; however, inconsistencies in individual performance prevented consistent modelling of the psychometric function due to response variability. In cases where stimulus intensity exceeded threshold levels, correct responses were often given without tracking the object, limiting smooth pursuit-based assessment. Smooth pursuit movements alone were insufficient for severity classification of colour vision deficiencies; further research is needed using additional eye movement metrics. |
Damian Koevoet; Christoph Strauch; Marnix Naber; Stefan Van der Stigchel Effort and salience jointly drive saccade selection Journal Article In: Psychonomic Bulletin & Review, vol. 32, no. 5, pp. 2363–2374, 2025. @article{Koevoet2025a,Choosing where to move the eyes ('saccade selection') is one of the most frequent human decisions and fundamentally shapes perception. Currently, saccade selection is thought to be predominantly driven by the observer's goals, selection history, and by the physical salience of stimuli. Recent work demonstrates that the inherent effort associated with planning and executing saccades ('saccade costs') also drives saccade selection: participants prefer making affordable over costly saccades. Do saccade costs still affect saccade selection when other factors such as salience attract gaze? Here, we addressed if, and how, saccade costs and salience together drive saccade selection by having participants freely choose between two potential saccade targets in different directions. Saccade targets either differed in salience or not, allowing us to disentangle the effects of saccade costs and salience. We observed that salience predicted saccade selection: participants chose salient over non-salient targets. Furthermore, saccade costs predicted saccade selection when equally salient targets were presented. When the possible targets differed in salience, the effect of saccade costs on saccade selection was reduced but not eliminated. Further analyses demonstrate that saccade costs and salience jointly drive saccade selection. Together, our results are in line with an accumulating body of work, and show that the role of effort in saccade selection is robust to salience. We conclude that effort must be considered a fundamental factor that drives where the eyes are moved. |
Marina Norkina; Daria Chernova; Svetlana Alexeeva; Maria Harchevnik In: Journal of Eye Movement Research, vol. 18, no. 5, pp. 1–27, 2025. @article{Norkina2025,Oculomotor reading behavior is influenced by both universal factors, like the “big three” of word length, frequency, and contextual predictability, and language-specific factors, such as script and grammar. The aim of this study was to examine the influence of the “big three” factors on L2 reading focusing on a typologically distant L1/L2 pair with dramatic differences in script and grammar. A total of 41 native Chinese-speaking learners of Russian (levels A2-B2) and 40 native Russian speakers read a corpus of 90 Russian sentences for comprehension. Their eye movements were recorded with EyeLink 1000+. We analyzed both early (gaze duration and skipping rate) and late (regression rate and rereading time) eye movement measures. As expected, the “big three” effects influenced oculomotor behavior in both L1 and L2 readers, being more pronounced for L2, but substantial differences were also revealed. Word frequency in L1 reading primarily influenced early processing stages, whereas in L2 reading it remained significant in later stages as well. Predictability had an immediate effect on skipping rates in L1 reading, while L2 readers only exhibited it in late measures. Word length was the only factor that interacted with L2 language exposure which demonstrated adjustment to alphabetic script and polymorphemic word structure. Our findings provide new insights into the processing challenges of L2 readers with typologically distant L1 backgrounds. |
Adrien Paire; Dorine Vergilino-Perez; Céline Paeye Vertical shifts of visuospatial attention, not (eye) movements, affect auditory pitch discrimination Journal Article In: Journal of Vision, vol. 25, no. 12, pp. 1–13, 2025. @article{Paire2025,Preparing an ocular saccade is known to affect not only the perception of various visual features, such as orientation, contrast, and numerosity, but also sound localization. In the present study, we tested whether saccade preparation influences the perception of other auditory features, such as the pitch of a tone played before eye movement. We also examined whether pitch could influence saccade characteristics, as an instance of response compatibility effects. At the beginning of each trial, a visual cue indicated that a disk would appear above or below fixation. Participants were then presented with a tone of varying frequency and were instructed either to make a saccade toward the peripheral disk after the tone ended or to maintain fixation on the center of the screen. Pitch was consistently overestimated when the disk appeared in the upper visual field compared with the lower visual field. However, we found no evidence that saccade preparation affected pitch perception and no evidence of response compatibility effects. These findings suggest that vertical shifts of visuospatial attention are sufficient to impact pitch discrimination, likely through the activation of the spatial representation inherent to pitch. |
Rosanne H. Timmerman; Antimo Buonocore; Alessio Fracasso Visual performance fields in saccadic suppression of image displacement Journal Article In: Experimental Brain Research, vol. 243, no. 10, pp. 1–17, 2025. @article{Timmerman2025,Visual perception is not homogeneous throughout the visual field. Performance is generally better along the horizontal meridian compared to the vertical meridian, and in the lower compared to the upper visual field. These asymmetries in visual performance are reflected in structural asymmetries in early visual cortex. When exploring a visual scene, eye movements occur continuously, with visual perception resulting from a tight interplay between the visual as well as the oculomotor systems. Literature on visual performance across visual fields during saccades is limited, but existing studies show that perceptual performance during saccades is indistinguishable between the upper and the lower visual fields, or altogether better in the upper visual field compared to lower. In the current exploratory study, we asked participants to detect the direction of target displacement across visual fields, while performing a saccade as well as at fixation. During fixation and saccade viewing conditions, performance on the task was better along the horizontal compared to the vertical meridian. However, we did not observe a robust difference in performance between the lower and upper visual field, neither at fixation nor when participants were requested to perform saccades. We interpret our results based on known behavioural and neural anisotropies, as well as considering evolutionary approaches to the perception–action cycle. |
Thomas D. W. Wilcockson; Sankanika Roy; Trevor J. Crawford Saccadic eye movements differentiate functional cognitive disorder from mild cognitive impairment Journal Article In: Perception, vol. 54, no. 10, pp. 768–779, 2025. @article{Wilcockson2025a,Functional Cognitive Disorder (“FCD”) is a type of Functional Neurological Disorder characterised by subjective cognitive complaints not fully attributable to brain injury, disease, or other neuropathological or psychiatric conditions. FCD is a cognitive impairment but does not necessarily “convert” to cognitive decline. However, FCD is common in Memory Clinics worldwide, and currently there is a lack of tests to objectively assess FCD. Establishing whether memory complaints are functional or not is vital for clinicians and objective tests are required. Previous research indicates that early-stage Alzheimer's disease can be differentiated from healthy individuals by antisaccade eye-movement. Therefore, eye movements may be able to objectively ascertain whether self-reported memory complaints are functional in nature. In this study, FCD participants were Memory Clinic patients who self-reported memory complaints but showed internal inconsistency regarding memory issues on memory tests. Participants with FCD were compared to Mild Cognitive Impairment (MCI) patients and healthy controls (HC) on antisaccadic and prosaccade eye movement tasks. The parameters obtained were reaction-time (RT) mean and SD and antisaccade error rate. MCI differed significantly from HC in antisaccade RT-mean, RT-SD, error-rate, and from FCD antisaccade RT-mean, RT-SD, and error-rate. FCD did not differ significantly from HC for antisaccade parameters. However, FCD differed significantly from HC for prosaccade RT-mean and RT-SD. MCI did not differ significantly from HC or FCD in prosaccade parameters. These results indicate that eye movement tasks could ultimately aid clinicians in the diagnosis of FCD. With additional research into sensitivity and specificity, eye movement tasks could become an important feature of memory clinics. |
Zhihao Zheng; Jiaqi Hu; Gouki Okazawa Spatiotemporal evidence accumulation through saccadic sampling for object recognition Journal Article In: The Journal of Neuroscience, vol. 45, no. 44, pp. 1–18, 2025. @article{Zheng2025d,Visual object recognition has been extensively studied under fixation conditions, but our natural viewing involves frequent saccadic eye movements that scan multiple local informative features within an object (e.g., eyes and mouth in a face image). These saccades would contribute to object recognition by subserving the integration of sensory information across local features, but mechanistic models underlying this process have yet to be established due to the presumed complexity of the interactions between the visual and oculomotor systems. Here, we employ a framework of perceptual decision making and show that human object categorization behavior with saccades can be quantitatively explained by a model that simply accumulates the sensory evidence available at each moment. Human participants of both sexes performed face and object categorization while they were allowed to freely make saccades to scan local features. Our model could successfully fit the data even during such a free viewing condition, departing from past studies that required controlled eye movements to test trans-saccadic integration. Moreover, further experimental results confirmed that active saccade commands (efference copy) do not substantially contribute to evidence accumulation. Therefore, we propose that object recognition with saccades can be approximated by a parsimonious decision-making model without assuming complex interactions between the visual and oculomotor systems. |
Xing Zhou; Yun Sun; Qi Zhang; Feifei Cui Distractor suppression driven by statistical regularities of target could occur only for larger search arrays Journal Article In: Attention, Perception, & Psychophysics, vol. 87, no. 7, pp. 2069–2084, 2025. @article{Zhou2025b,A number of studies have suggested that biasing the probability by which distractors appear at locations in visual space may lead to attentional suppression of high-probability distractor locations. It effectively reduces capture by a distractor but also impairs target selection at this location. Recently, there is still debate on whether the distractor processing could be affected by the statistical regularities of the target location. In the current study, through four experiments, we manipulated search array size (the number of the elements on the display – four, six, ten, 12). In each experiment, we manipulated spatial regularities of the target including one low-probability target location and other high-probability target locations. We found that statistical regularities of the target location could affect the distractor processing, but this occurred only for larger search array sizes (e.g., ten and 12 elements). Our new finding provided the evidence for whether statistical regularities regarding the target could affect distractor processing. We concluded that search array size was a potential and critical factor for determining whether distractor suppression could be driven by statistical regularities of target location. |
Yiting Ding; Weiting Tang; Zengzhen Yin; Zhongling Wu; Haojun Yang In: Sleep Medicine, vol. 134, pp. 1–8, 2025. @article{Ding2025b,Aim: To explore the potential synergistic effect of sleep-related disruptions (SRD) on attention dysfunction in temporal lobe epilepsy (TLE), focusing on how SRD impacts specific attention networks, including alertness, orientation, and executive control. Methods: Ninety-three patients with TLE and matched healthy controls participated. Attention was assessed using the Attention Network Test (ANT) and eye-tracking data, while SRD severity was determined via the Pittsburgh Sleep Quality Index. Participants were categorized based on SRD severity, and attention performance across the three networks was evaluated. Results: Patients with TLE demonstrated significant attention impairments, predominantly affecting the alertness and executive control networks. SRD aggravated these deficits, particularly in the alertness network, with more severe SRD correlating with greater dysfunction. Moderate to severe SRD led to significant declines in alertness, while minimal SRD showed no substantial impact on attention performance. Conclusion: SRD exacerbates attention dysfunction in patients with TLE, particularly within the alertness network. These findings highlight the critical role of sleep quality in managing cognitive function in TLE and suggest early intervention for patients with significant SRD to improve outcomes. |
Hyunwoo Gu; Joonwon Lee; Sungje Kim; Jaeseob Lim; Hyang Jung Lee; Heeseung Lee; Min Jin Choe; Dong Yoo; Jun Hwan (Joshua) Ryu; Sukbin Lim; Sang Hun Lee Attractor dynamics of working memory explain a concurrent evolution of stimulus-specific and decision-consistent biases in visual estimation Journal Article In: Neuron, vol. 113, no. 20, pp. 3476–3490, 2025. @article{Gu2025a,Sensory evidence tends to be fleeting, often unavailable when we categorize or estimate world features. To overcome this, our brains sustain sensory information in working memory (WM). Although keeping that information accurate while acting on it is vital, humans display two canonical biases: estimates are biased toward a few stimuli (“stimulus-specific bias”) and prior decisions (“decision-consistent bias”). Integrative—especially neural mechanistic—accounts of these biases remain scarce. Here, we identify drift dynamics toward discrete attractors as a common source of both biases in orientation estimation, with decisions further steering memory states. Behavior and neuroimaging data reveal how these biases co-evolve through the decision-steered attractor dynamics. Task-optimized recurrent neural networks suggest neural mechanisms that enable categorical decisions to emerge from WM for continuous stimuli while updating their trajectory, warping decision-consistent biases under stimulus-specific drift. |
Eleni Peristeri; Michaela Nerantzini; Timothy C. Papadopoulos; Spyridoula Varlokosta Autistic children's reading comprehension revisited through eye-tracking: Evidence from bridging inferencing Journal Article In: Research in Autism, vol. 128, pp. 1–14, 2025. @article{Peristeri2025,Pragmatic language impairments are universally observed in Autism Spectrum Disorders. Inferencing, i.e., combining information within text and using background knowledge to go beyond what is explicitly stated in the text to make a conjecture, has been a challenging pragmatic domain for autistic children. Most studies that have investigated inferencing in autism have used behavioral measurements. The objective of the current study was to assess inferencing in autistic and age-matched typically-developing children by employing eye-tracking to capture children's ‘in-the-moment' eye gaze behaviors while reading short passages. We also investigated links between children's inferencing and executive function skills. The study included 19 autistic children and 19 age-matched typically-developing children. Groups were administered an eye-tracking task that assessed children's inferencing skills while reading short vignettes that differed in a critical word that supported inferencing or not. Children were asked to read the vignettes and then answer questions that were either primed or not by the inference. The two groups were also assessed on executive functions, including working memory and attention. We found that autistic children exhibited lower comprehension accuracy in passages not primed by inferencing as compared to those that were primed, and also spent more looking time on primed passages than the typically-developing children. Moreover, while inferencing in typically-developing children was significantly related to their executive function skills, no such relations were observed for the autistic group. The overall findings show that reading comprehension for the autistic children was reduced when questions did not anchor to previous discourse through bridging inferencing. Finally, inferencing in the autistic group did not rely on executive functions to the same extent as in typically-developing children. |
Sotiris Plainis; Angeliki Gleni Soft toric contact lens correction of moderate astigmatism improves digital reading performance and oculomotor behaviour: An eye movement study Journal Article In: Contact Lens and Anterior Eye, vol. 48, no. 5, pp. 1–9, 2025. @article{Plainis2025,Purpose: Reading on digital devices is a crucial daily activity. In this study, oculomotor behaviour and reading performance were evaluated in patients with low to moderate astigmatism corrected with spherical or toric lenses, before and after a short reading task on a tablet. Μethods: Silent reading performance and visual acuity (VA) of twenty four volunteers (age: 30 ± 8 yrs) was assessed binocularly with IReST passages (0.3 logMAR print size) for two contrast levels (100 % and 10 %) at 40 cm screen distance. Participants were corrected for their binocular myopic astigmatism using daily disposable contact lenses (PRECISION1, Alcon Laboratories) in either single vision (spherical) or toric design (of 0.75D or 1.25D cylinder). Recordings were repeated after a 10-minute reading activity on a tablet. Eye movements were monitored with an infrared eyetracker. Data analysis included computation of reading speed and a range of oculomotor indices. Results: Average VA improved at near with toric compared to spherical lens correction at both contrast levels (high: 0.06 ± 0.07 logMAR |
Irene S. Plank; Anna Yurova; Alexandra Pior; Julia Nowak; Afton M. Bierlich; Boris Papazov; Zhuanghua Shi; Christine M. Falter-Wagner Are prediction error modifications domain specific in autism but domain general in ADHD? Journal Article In: Imaging Neuroscience, vol. 3, pp. 1–16, 2025. @article{Plank2025,In the last decade, several theories have proposed explanations of autism spectrum disorder (ASD) based on the Bayesian Brain hypothesis. Research on repetition suppression suggests that neural correlates of prediction errors in ASD might be domain specific with larger differences for faces than for objects. Contrastingly, research assessing mismatch negativity in attention-deficit/hyperactivity disorder (ADHD) indicates domain-generally modified prediction errors. Therefore, we captured neural correlates of prediction errors to colours and emotions in adults with ADHD or ASD to assess domain specificity of prediction error modifications. We used a multi-feature roving paradigm where we assessed predictive processes regarding unattended, task-irrelevant faces. We extracted task specific precision-weighted prediction errors and prediction strength for emotions and colours of the faces separately using a generative model, specifically a Hierarchical Gaussian Filter. While we found neural correlates of colour precision-weighted prediction errors and prediction strength as well as emotion prediction strength in the pooled sample regardless of group, we did not find any differences in neural correlates of emotion or colour precision-weighted prediction errors or prediction strength between our groups. These results suggest preserved neural correlates of precision-weighted prediction errors in ASD and ADHD for low-level visual features and potentially complex social information. |
Lara Koch; Benedikt Reuter; Norbert Kathmann In: Cognitive Therapy and Research, vol. 49, no. 5, pp. 1031–1044, 2025. @article{Koch2025a,Background: Attentional biases to emotional information are assumed to play a crucial role in the onset and maintenance of depression. Moreover, recent studies show that biases may remain present in previously affected individuals during non-symptomatic stages even after acute depression has fully subsided. For example, in an investigation probing attentional disengagement from facial expressions of happiness, sadness, and disgust, never-depressed individuals showed speeded disengagement from disgusted expressions in comparison to happy faces, but this differential processing pattern was absent in currently euthymic individuals with a history of major depression. Purpose: Building on these findings, the present follow-up study aimed to explore the predictive power of that previously described disengagement bias by assessing depressive symptoms in 63 initially euthymic individuals six months after they had participated in a gaze-contingent eye tracking task. Methods: Each participants' mean difference in saccade latency to initiate eye movements away from facial expressions of happiness and disgust was assessed at baseline, and tested for associations with self-reported depressive symptom gains six months later. Results: The individual's difference between these two emotion conditions when performing attentional disengagement (ADΔhappiness-disgust) significantly predicted the occurrence of a reliable increase in depressive symptom severity at six months follow-up. This effect remained significant when controlling for baseline symptom severity and lifetime history of depression. Conversely, dimensional change in depressive symptom severity was not predicted by the ADΔhappiness-disgust score. Conclusions: We suggest that an individual difference score reflecting the ability to disengage attention from facial expressions of disgust versus happiness may be particularly useful in identifying individuals prone to experiencing reliable increases in depressive symptoms. |
Anne Wienholz; Amy M. Lieberman Tracking effects of age of sign language acquisition and phonology in American Sign Language sentence processing Journal Article In: Memory & Cognition, vol. 53, no. 7, pp. 2009–2027, 2025. @article{Wienholz2025,Processing sign language involves activation of phonological features of signs. Previous research provides evidence for effects of age of sign language acquisition as well as amount and type of phonological relatedness during processing of single signs, but it is unknown how these factors affect sentence-level sign processing. This paper presents a phonological priming eye tracking study of American Sign Language (ASL) processing, in which we systematically vary the degree and type of phonological relatedness in prime-target sign pairs embedded in ASL sentences. We tested degree of relatedness by using sign pairs sharing either one or two out of three phonological parameters. We tested type of relatedness by using signs that were phonologically related in all possible combinations of the parameters handshape, location, and movement. Participants were exposed to sign language either early (before the age of five years) or late (after the age of five years), allowing us to explore how age of sign language acquisition impacts activation of phonological features of signs. Late signers were more affected by the degree of relatedness than early signers; primes that shared any information with the target led to increased time to identify the target, regardless of the specific parameter(s) that overlapped. There was a high degree of variability for type of relatedness, but sign pairs that shared location were particularly salient. Group differences suggested varying sensitivities to phonological information in early and late signers. Our study emphasizes that phonological relatedness should be carefully controlled when examining sign processing in signers differing in their language backgrounds. |
Haojun Yang; Qiong Zhang; Kailing Huang; Li Feng More fixations in static facial regions during emotion recognition among TLE patients with severe depression Journal Article In: CNS Neuroscience and Therapeutics, vol. 31, no. 10, pp. 1–8, 2025. @article{Yang2025b,Aim: To explore the emotion recognition (ER) abilities among temporal lobe epilepsy (TLE) patients with different levels of depression. Methods: This observational study was conducted during December 2021 and November 2022, including 71 healthy controls (HCs) and 93 TLE patients. Based on the scores of the Beck Depression Index, the patients were divided into four groups (no/mild/moderate/severe depression). All participants finished the Faux pas task (FPT), watched the dynamic facial expression task and recognized the emotion (anger, disgust, happiness, or sadness) with the recording of eye movements. The accuracy of ER was recorded. The percentage of fixation in interested areas (IA) and fixation counts in IA were selected and analyzed. Results: TLE patients without depression had significantly lower FPT scores (p = 0.001) and accuracy ratios of dynamic facial ER (p = 0.039) than HCs. Patients with severe depression had significantly more fixation percentages and fixation counts in the nose than patients with no/mild/moderate depression (p < 0.05). Conclusion: The recording of eye movement provides more accurate and objective biobehavioral indicators for distinguishing TLE patients with severe depression, which has great practical significance for early monitoring and intervention. |
Hossein Abbasi; Cynthia D. King; Stephanie Lovich; Brigitte Röder; Jennifer M. Groh; Patrick Bruns Eye movement-related eardrum oscillations do not require current visual input Journal Article In: Hearing Research, vol. 465, pp. 1–11, 2025. @article{Abbasi2025,Oculomotor signals influence the neural processing of auditory input. Recent studies have shown that this connection extends to the auditory periphery: The phase and amplitude of eardrum oscillations was systematically influenced by eye movement direction and magnitude, a phenomenon called eye movement-related eardrum oscillations (EMREOs). Previous findings have suggested that EMREOs occur independently from auditory stimulation, but it is unknown whether they depend on the presence of visual sensory input or solely reflect efference copies of the oculomotor system. To distinguish between these two alternatives, we measured eye movements and eardrum oscillations in sighted human participants who performed free saccadic eye movements in darkness. Despite the lack of any sensory stimulation during eye movements, significant EMREOs occurred in all participants. EMREO characteristics were comparable to a separate control experiment in which participants performed guided saccades to visual targets and were robust to different types of eye tracker calibration methods. Thus, our results suggest that EMREOs are not driven by bottom-up sensory signals but rather reflect a pure influence of oculomotor signals on peripheral auditory processing. This indicates that EMREOs might play a crucial role in reference frame transformations which are needed for audio-visual spatial integration. |
Annabell Coors; Weiyi Zeng; Ulrich Ettinger; Monique M. B. Breteler Neuropathology determines whether brain systems segregation benefits cognitive performance Journal Article In: Imaging Neuroscience, vol. 3, pp. 1–15, 2025. @article{Coors2025,The human brain is a large-scale network, containing multiple segregated, functionally specialized systems. With increasing age, these systems become less segregated, but the reasons and consequences of this age-related reorganization are largely unknown. Thus, after characterizing age- and sex-specific differences in the segregation of global, sensorimotor, and association systems using resting-state functional MRI data, we analyzed how segregation relates to cognitive performance in both classical and eye movement tasks across age strata and whether this is influenced by the degree of neuropathology. Our analyses included 6,455 participants (30–95 years) of the community-based Rhineland Study. System segregation indices were based on functional connectivity within and between 12 brain systems. We assessed cognitive performance with tests for memory, processing speed, executive function, and crystallized intelligence and oculomotor tasks. Multivariable regression models confirmed that brain systems become less segregated with age (e.g., global segregation: standardized regression coefficient (ß) = -0.298; 95% confidence interval [-0.299, -0.297], p < 0.001) and that in older age this effect is stronger in women compared to men. Higher segregation benefited memory (especially in young individuals) and processing speed in individuals with mild neuropathology (not significant after multiple testing correction). Lower segregation benefited crystallized intelligence in 46- to 55-year-olds. Associations between segregation indices and cognition were generally weak (ß ~ 0.01–0.06). This suggests that optimal brain organization may depend on the degree of brain pathology. Age-related brain reorganization could serve as a compensatory mechanism and partly explain improvements in crystallized intelligence and the decline in fluid cognitive domains from adolescence to (late) adulthood. |
Katherine Farber; Linjing Jiang; Mario Michiels; Ignacio Obeso; Hoi-Chung Leung Microsaccade activity during visuospatial working memory in early-stage Parkinson's disease Journal Article In: Journal of Eye Movement Research, vol. 18, no. 5, pp. 1–17, 2025. @article{Farber2025,Fixational saccadic eye movements (microsaccades) have been associated with cognitive processes, especially in tasks requiring spatial attention and memory. Alterations in oculomotor and cognitive control are commonly observed in Parkinson's disease (PD), though it is unclear to what extent microsaccade activity is affected. We acquired eye movement data from sixteen participants with early-stage PD and thirteen older healthy controls to examine the effects of dopamine modulation on microsaccade activity during the delay period of a spatial working memory task. Some microsaccade characteristics, like amplitude and duration, were moderately larger in the PD participants when they were “on” their dopaminergic medication than healthy controls, or when they were “off” medication, while PD participants exhibited microsaccades with a linear amplitude–velocity relationship comparable to controls. Both groups showed similar microsaccade rate patterns across task events, with most participants showing a horizontal bias in microsaccade direction during the delay period regardless of the remembered target location. Overall, our data suggest minimal involvement of microsaccades during visuospatial working memory maintenance under conditions without explicit attentional cues in both subject groups. However, moderate effects of PD-related dopamine deficiency were observed for microsaccade size during working memory maintenance. |
Jan Nikolas Klanke; Sven Ohl; Martin Rolfs Sensorimotor awareness requires intention: Evidence from minuscule eye movements Journal Article In: Cognition, vol. 262, pp. 1–12, 2025. @article{Klanke2025,Microsaccades are tiny eye movements typically occurring spontaneously and without awareness but can also be intentionally controlled with high precision. We used these tiny visual actions to investigate how intention modulates sensorimotor awareness by directly comparing intended (upon instruction), unintended (occurring despite instruction to fixate), and spontaneous microsaccades. In addition, we dissociated the effects of action intention and the actions' visual consequences on awareness. To achieve this, we presented a stimulus at high temporal frequency rendering it invisible during stable fixation. Critically, this stimulus became visible when it slowed down on the retina, either incidentally, due to a microsaccade with comparable direction and speed, or physically, when replaying the retinal consequence of previous microsaccades. Trials without a stimulus were included as control. Participants reported whether they perceived the stimulus (visual sensitivity), whether they believed they had made a microsaccade (microsaccade sensitivity), and their level of confidence that their eye movement behavior was linked to their perception (causality assignment). Visual sensitivity was high for both generated and replayed microsaccades and comparable for intended, unintended, and spontaneous eye movements. Microsaccade sensitivity, however, was low for spontaneous microsaccades, but heightened for both intended and unintended movements. Thus, the intention to saccade or fixate enhances awareness of otherwise undetected eye movements. Visual consequences failed to aid eye movement awareness, and confidence ratings revealed a poor understanding of a causal relationship between eye movement and sensory consequence. These findings highlight the functional relevance of intention in sensorimotor awareness at the smallest scale of visual actions. |
Sandra Klonteig; Elise S. Roalsø; Brage Kraft; Torgeir Moberget; Eva Hilland; Peyman Mirtaheri; Rune Jonassen In: Journal of Behavior Therapy and Experimental Psychiatry, vol. 88, pp. 1–12, 2025. @article{Klonteig2025,Background: Attentional bias (AB) is characterized by preferential cognitive and emotional processing of mood-congruent stimuli and considered a central mechanism in mood disorders. Considerable research has focused on improving AB measures to enhance mechanistic understanding and clinical utility. The present study examines psychometric properties of a range of AB measures with a multimodal setup. Methods: A nonclinical sample of 62 women aged 20–30 years completed the facial dot-probe task while behavioral responses (reaction time), eye-gaze patterns (eye tracking), and electrical brain potentials (electroencephalography) were recorded. AB metrics from four types of AB measures – traditional, response-based, dwell time, and the N2pc component– were examined with internal consistency and short-term test-retest calculations. AB metrics with an internal consistency score over .4 were considered reliable, and their validity were explored by examining relations to depression and anxiety symptoms. In addition, the consistency between reliable metrics across trials were examined. Results: Findings show that traditional AB metrics exhibited no degree of reliability, whereas response-based and dwell time metrics overall demonstrated better internal consistencies. Response-based metrics also had higher test-retest reliability in all but one metric. The previously reported reliability of the N2pc component was not observed. As for validity, no linear associations were found between the reliable measures, depression, and anxiety. There were no relations between metrics across trials. Conclusions: This study provides insights for future AB research, emphasizing the potential of novel metrics over traditional ones and the use of multimodal setups to develop reliable and potentially hybrid measurements for clinical assessment. |
Baiwei Liu; Siyang Kong; Freek Ede Microsaccades strongly modulate but do not directly cause the EEG N2pc marker of spatial attention Journal Article In: PLoS biology, vol. 23, no. 9, pp. 1–17, 2025. @article{Liu2025c,The N2pc is a popular human-neuroscience marker of covert and internal spatial attention that occurs 200-300 ms after being prompted to shift attention-a time window also characterized by the spatial biasing of small fixational eye movements known as microsaccades. Here, we show how co-occurring microsaccades profoundly modulate N2pc amplitude during top-down shifts of spatial attention in both perception and working memory. At the same time, we show that a significant-albeit severely weakened-N2pc can still be established in the absence of co-occurring microsaccades. Moreover, despite the strong modulation of the N2pc by microsaccade presence and direction, the N2pc does not align to the precise timing of microsaccades, ruling out that the observed N2pc modulations by microsaccades are a direct artifact of microsaccade-related eye-muscle activity, corneo-retinal dipole movement, or visual inputs moving over the retina. Thus, while microsaccades strongly modulate N2pc amplitude, microsaccades themselves are not a prerequisite for, nor a direct cause of, the N2pc. |
Diane Mézière; Johanna K. Kaakinen; Emilia Ranta; Karin Kukkonen; Jonathan Smallwood; Jaana Simola Do eye movements reflect readers' thoughts during reading? Evidence from multidimensional experience sampling and eye movements Journal Article In: Consciousness and Cognition, vol. 134, pp. 1–17, 2025. @article{Meziere2025a,While reading narrative texts, readers' attention often fluctuates from the text (e.g., immersion) to text-unrelated thoughts (e.g., mind-wandering). Research on mind-wandering and immersion suggests that they influence the reading process differently. In this article, we examine the types of thoughts readers have while reading a literary text. Specifically, we investigated the effect of immersion and mind-wandering on eye-movement behaviour during reading. Fifty-six participants read extracts from a novel while their eye-movements were monitored. Participants' thoughts were probed using multidimensional experience sampling. We identified four types of thought: Immersion, Mind-wandering, Sub-Vocalization, and Social Episodic Thoughts. We then ran General Additive Mixed Models (GAMMs) to examine the relationship between these thought types and eye movements. Results show that eye movements are influenced by the types of thoughts readers experience while reading literary texts. These results have important implications for the way that mind-wandering is typically investigated, particularly in reading research. |
Richard Schweitzer; Thomas Seel; Jörg Raisch; Martin Rolfs Early visual signatures and benefits of intra-saccadic motion streaks Journal Article In: PLoS Computational Biology, vol. 21, no. 9, pp. 1–37, 2025. @article{Schweitzer2025a,Eye movements routinely induce motion streaks as they shift visual projections across the retina at high speeds. To investigate the visual consequences of intra-saccadic motion streaks, we co-registered eye tracking and EEG while gaze-contingently shifting target objects during saccades, presenting either continuous, 'streaky' or apparent, step-like motion in four directions. We found significant reductions of secondary saccade latency, as well as improved decoding of the post-saccadic target location from the EEG signal when motion streaks were available. These signals arose as early as 50 ms after saccade offset and had a clear occipital topography. Using a physiologically plausible visual processing model, we provide evidence that the target's motion trajectory is coded in orientation-selective channels and that speed of gaze correction was linked to the visual dynamics arising from the combination of saccadic and target motion, providing a parsimonious explanation of the behavioral benefits of intra-saccadic motion streaks. |
Vivek Srivastava; Sakshi Patel Multi-model fusion of Ornstein–Uhlenbeck process and RNN-XGBoost for biometric person identification using eye movement patterns Journal Article In: Computers in Biology and Medicine, vol. 196, pp. 1–12, 2025. @article{Srivastava2025,This paper introduces a novel framework for biometric person identification based on distinctive eye movement patterns. Grounded in foraging theory, the approach leverages the Ornstein–Uhlenbeck (O–U) process to model the dynamics of visual exploration and exploitation during gaze behavior. Eye movement data, including fixations and saccades, is analyzed using Bayesian estimation of a stochastic differential equation to extract individual-specific features. The extracted features are subsequently classified using a hybrid model combining Recurrent Neural Networks (RNN) and XGBoost. This multi-model fusion enhances robustness and discriminative capability. The method is evaluated using the publicly available FIFA eye-tracking dataset, achieving an average accuracy of 94%, F1-score of 94.03%, and an Area Under the ROC Curve (AUC) of 98.97%, with a corresponding Equal Error Rate (EER) of 4.0%. |
Matteo Valsecchi; Mario Dalmaso; Luigi Castelli; Eleonora Baldini; Giovanni Galfano Is mind wandering reflected in microsaccade dynamics? Journal Article In: Biological Psychology, vol. 200, pp. 1–15, 2025. @article{Valsecchi2025,Mind wandering is a state in which our mental processes are directed towards task-unrelated thoughts. This phenomenon has been shown to underlie attentional lapses and represents a common experience in everyday life. Previous studies have found an association between mind wandering and eye-related indices. In the present study, we addressed for the first time whether the rate of microsaccades—miniaturised saccades that we spontaneously produce during prolonged fixation—is sensitive to the occurrence of mind wandering. Participants performed the Sustained Attention to Response Task, a go/no-go task highly vulnerable to mind wandering. The analyses focused on possible differences in microsaccade rate emerging from the comparison of time intervals preceding commission errors and time intervals preceding correct target withholds, under the assumption that a commission error would reflect a mind wandering episode. The results showed that microsaccadic rate was consistently reduced in time windows preceding a target trial in which participants produced a commission error as compared to when they correctly inhibited the tendency to manually respond. Cluster-based analyses established that this pattern was robust. Because microsaccades are known to occur involuntarily and a reduction in their frequency has been associated with higher mental effort, the present findings provide new insights as regards the relevance of mind wandering and lend support to the idea that during mind wandering our mind is far from being idle and is absorbed and committed to effortful activities instead. |
Lauren S. Baron; Anna M. Ehrhorn; Peter Shlanta; Jane Ashby; Bethany A. Bell; Suzanne M. Adlof Orthographic influences on phonological processing in children with and without reading difficulties: An eye-tracking study Journal Article In: Reading and Writing, vol. 38, no. 7, pp. 1925–1948, 2025. @article{Baron2025,Phonological processing is an important contributor to decoding and spelling difficulties, but it does not fully explain word reading outcomes for all children. As orthographic knowledge is acquired, it influences phonological processing in typical readers. In the present study, we examined whether orthography affects phonological processing differently for children with current reading difficulties (RD), children with a history of reading difficulties who are currently presenting with typical word reading skills (Hx), and children with typical development and no history of reading difficulties (TD). School-aged children completed a phonological awareness task containing spoken words and pictures while eye movements were recorded. In this task, children had to pair a spoken stimulus word with one of four pictures that ended with the same sound. Within the task, stimulus-target picture pairs varied in the congruency and consistency of the orthographic and phonological mappings of their final consonant sounds. Eye movements revealed that children with typical word reading (the Hx and TD groups) showed better discrimination of the target from the foils compared to peers with underdeveloped word reading skills. All children were more accurate when stimulus-target pairs were congruent and consistent than when they were incongruent or inconsistent. Orthography plays an important role in the completion of phonological awareness tasks, even in the absence of written words and for children with a wide range of reading abilities. Results highlight the importance of considering orthography during interventions for phonological awareness and word reading. |
Addison D. N. Billing; Eleanor S. Smith; Robert J. Cooper; Rebecca P. Lawson Maternal anxiety shapes prediction error responses in the infant brain Journal Article In: Neurophotonics, vol. 12, no. 03, pp. 1–16, 2025. @article{Billing2025,SIGNIFICANCE: Postnatal maternal anxiety affects a substantial number of new mothers and is linked to long-term risk for anxiety in their offspring. Yet, the neural mechanisms through which postnatal maternal anxiety influences early cognitive development remain unclear. We investigated whether postnatal maternal anxiety shapes how infant brains respond to unexpected events-prediction errors-which are central to learning in uncertain environments. AIM: We examined prediction error processing in 6- to 8-month-old infants using high-density diffuse optical tomography and eye-tracking. We hypothesized that neural responses in the medial prefrontal cortex (mPFC) would vary with maternal anxiety levels. APPROACH: Infants viewed audiovisual events where expected outcomes were occasionally omitted, eliciting prediction errors. Hemodynamic responses in the frontal cortex were analyzed using a general linear model, with trial-by-trial gaze data as a parametric modulator. Maternal anxiety was measured using the state-trait anxiety inventory. RESULTS: Prediction error responses were localized to the mPFC and were only detectable when controlling for infant attention using eye-tracking. Cortical activation in response to unexpected stimuli was significantly enhanced in infants of mothers with higher trait anxiety. CONCLUSION: Our findings suggest that maternal anxiety modulates prediction error processing in the infant brain, potentially shaping early sensitivity to environmental unpredictability and conferring risk for later anxiety. |
A. J. Glazebrook; Jane Shakespeare-Finch; Patrick J. Johnston; Jonathan E. Robinson Dwelling on the positive: Eye-tracking and electroencephalogram indicators of posttraumatic growth Journal Article In: Psychological Trauma: Theory, Research, Practice, and Policy, pp. 1–14, 2025. @article{Glazebrook2025,OBJECTIVE: Since existing research demonstrates people with posttraumatic stress disorder (PTSD) direct more attention toward negative and threatening visual stimuli, this study hypothesized people with posttraumatic growth (PTG) may direct increased attention toward positive visual stimuli. METHOD: To examine this hypothesis, eye-tracking data and electroencephalogram brain activity recorded during the N170 time window were collected for 72 healthy individuals with varying trauma exposures as they passively viewed positively and negatively valenced images in a two-phase study design. PTG and PTSD symptoms in this nonclinical sample were measured using the Posttraumatic Growth Inventory (Tedeschi & Calhoun, 1996) and the Impacts of Events Scale-Revised (Weiss & Marmar, 1997). N170 was examined as existing research identifies N170 as an early electrophysiological inflection sensitive to context. RESULTS: Analysis revealed that as overall PTG and Posttraumatic Growth Inventory subfactor "appreciation of life" increased, participant pupil dilations also increased, and participants were more likely to gaze first and dwell for longer on positively valenced images. There was no association between N170 and PTG. However, increased PTSD symptoms were associated with a larger N170 responsivity to negatively valenced images. CONCLUSION: Eye-tracking findings offer novel physiological evidence of the salience of positive imagery for people with greater PTG. Larger N170 responses to negative images may offer a physiological marker of the pronounced threat recognition present in people with increased PTSD symptom severity. The propensity for individuals with more PTG to focus on positive, life-affirming images may underpin the more constructive worldviews and contemplative deliberate rumination, meaning-making, and constructive coping efforts associated with PTG development. |
Yao-Tung Lee; Yi-Hsuan Chang; Cesar Barquero; Chi-Shin Wu; Shu-Ping Chao; David Yen-Ting Chen; Jui‐Tai Chen; Yih‐Giun Cherng; Chin-An Wang Pupil and eye blink response abnormalities during emotional conflict processing in late-life depression Journal Article In: Journal of Geriatric Psychiatry and Neurology, vol. 38, no. 5, pp. 378–393, 2025. @article{Lee2025c,Introduction: This study aims to investigate the locus coeruleus-norepinephrine system (LC-NE) function in late-life depression (LLD) patients by examining task-evoked pupil dilation in the emotional face-word Stroop task, given the recently established coupling between task-evoked pupil dilation and LC-NE activation. Materials and Methods: Using video-based eye-tracking and principal component analysis, we explored task-evoked pupil responses and eye blinks in LLD patients (N = 25) and older healthy controls (CTRL) (N = 29) to determine whether there were alterations in pupil responses and eye blinks in LLD compared to CTRL. Results: LLD patients exhibited significantly different pupil and eye-blink behavior compared to CTRL, with dampened task-evoked pupil dilation associated with emotional congruency and valence processing mediated by the sympathetic system compared to CTRL. Eye-blink rates associated with emotional valence were also altered in LLD compared to CTRL Moreover, Geriatric Depression Scale-15 scores in LLD correlated with emotional congruency effects revealed by task-evoked pupil dilation. Conclusion: The findings demonstrate that LLD patients display altered pupil behavior compared to CTRL. These altered responses correlated with the severity of depressive symptoms, indicating their potential as objective biomarkers for use in large at-risk populations for LLD. |
Swati Sharma; Mrinmoy Chakrabarty; Sonia Baloni Ray; Jainendra Shukla Machine learning-driven analysis of temporal pupil dynamics for interpretable ADHD diagnosis Journal Article In: Computers in Biology and Medicine, vol. 196, pp. 1–16, 2025. @article{Sharma2025b,Attention-deficit/hyperactivity disorder (ADHD) is a prevalent neurodevelopmental disorder characterized by inattention and hyperactivity. Current diagnostic methods rely on bias-prone subjective assessments, such as clinical interviews and behavior rating scales. Objective biomarkers remain elusive hindering standardized ADHD diagnosis. Pupillometry, measuring pupil responses linked to cognition and attention, offers a promising, objective alternative. However, prior work often overlooks clinically relevant features and lacks interpretability, limiting clinical adoption. We introduce an interpretable machine-learning framework leveraging temporal pupil dynamics to classify ADHD and control groups. The primary novelty of our work lies in identifying and statistically validating task-aligned features-specifically, novel dynamic pupil dilation and constriction rates extracted in block-wise temporal segments-which capture subtle attentional fluctuations overlooked by prior models. We analyzed published pupillometry data from 49 participants (21 controls, 28 ADHD, 17 assessed on and off medication) during a visuospatial working memory task. Candidate features were identified through statistical analyses using mixed analysis of variance. Classification models were trained to prioritize interpretability by utilizing statistically significant, literature-supported features. Model transparency was enhanced with heatmaps and feature-importance charts. The models demonstrated strong classification performance: using pupil features alone yielded 84.4% accuracy (area under the receiver operating characteristic (AUROC) 88.6%). Including task performance improved accuracy to 86.7% (AUROC 91.5%). Final integration of reaction time metrics achieved 88.9% accuracy (AUROC 90.8%), with 97.8% sensitivity and 82.2% specificity. By leveraging interpretable, dynamic pupil metrics, our approach advances objective, reproducible ADHD diagnosis and supports clinical deployment. |
Laure Trinquet; Suzon Ajasse; Frédéric Chavane; Richard Legras; Frédéric Matonti; José Alain Sahel; Catherine Vignal-Clermont; Jean Lorenceau Uncovering the characteristics of pupil cycle time (PCT) in neuropathies and retinopathies Journal Article In: Vision, vol. 9, no. 3, pp. 1–22, 2025. @article{Trinquet2025,Pupil cycle time (PCT) estimates the dynamics of a biofeedback loop established between pupil size and stimulus luminance, size or colour. The PCT is useful for probing the functional integrity of the retinopupillary circuits, and is therefore potentially applicable for assessing the effects of damage due to retinopathies or neuropathies. In previous studies, PCT was measured by manually counting the number of pupil oscillations during a fixed period to calculate the PCT. This method is scarce, requires a good expertise and cannot be used to estimate several PCT parameters, such as the oscillation amplitude or variability. We have developed a computerised setup based on eye-tracking that expands the possibilities of characterising PCT along several dimensions: oscillation frequency and regularity, amplitude and variability, which can be used with a large palette of stimuli (different colours, sizes, shapes or locations), and further allows measuring blinking frequency and eye movements. We used this method to characterise the PCT in young control participants as well as in patients with several pathologies, including age-related macular degeneration (AMD), diabetic retinopathy (DR), retinitis pigmentosa (RP), Stargardt disease (SD), and Leber hereditary optic neuropathy (LHON). We found that PCT is very regular and stable in young healthy participants, with little inter-individual variability. In contrast, several PCT features are altered in older healthy participants as well as in ocular diseases, including slower dynamics, irregular oscillations, and reduced oscillation amplitude. The distinction between patients and healthy participants based on the calculation of the area under the curve of the receiver operating characteristics (AUC of ROC) were dependent on the pathologies and stimuli (0.7 < AUC < 1). PCT nevertheless provides relevant complementary information to assess the physiopathology of ocular diseases and to probe the functioning of retino-pupillary circuits. |
Li Zhou; Valerie Benson Attentional disengagement differences in young children with autism: A comparative eye-movement study using static and dynamic stimuli Journal Article In: Research in Autism, vol. 127, pp. 1–13, 2025. @article{Zhou2025,Weak attentional disengagement represents a crucial concern in children with Autism Spectrum Condition (ASC). Failure to disengage from attended stimuli has obvious consequences for the development of everyday communication skills, and in the real world, stimuli are often dynamic as well as static. In this study, we recorded eye movements and investigated attentional disengagement in young Chinese children with and without ASC for static and dynamic stimuli. Our approach employed the gap-overlap paradigm (GOP) with stimuli consisting of static (Experiment 1: 44 ASC, 47 typically developing (TD)) or dynamic (Experiment 2: 26 ASC, 26 TD) geometric figures. Basic oculomotor function was intact in both groups. No significant group differences were observed for reflexive saccades and attentional orienting between ASC and TD children using the classic GOP. However, young children with ASC consistently exhibited prolonged voluntary disengagement (longer saccade latencies) in a modified-overlap task across both stimulus types. Furthermore, ASC children demonstrated more delayed disengagement when presented with dynamic foveal stimuli consisting of repetitive motion compared to random motion, and this effect was absent in TD children. These findings reflect how attentional biases to both static and repetitive dynamic stimuli impact upon visual disengagement, and hence have the potential to influence future development of social cognition in individuals with ASC. |
Jolanda Buonocore; Alessio Facchin; Marianna Crasà; Giulia Sgrò; Alessia Cristofaro; Aldo Quattrone; Andrea Quattrone Eye movement abnormalities in Parkinson's disease motor subtypes: A video-oculographic study Journal Article In: Neurological Sciences, vol. 46, no. 8, pp. 3677–3684, 2025. @article{Buonocore2025,Introduction: Eye movement dysfunction has been described in Parkinson's disease (PD), but differences between tremor-dominant (TD) and postural instability/gait difficulty (PIGD) PD motor subtypes remain poorly understood. The aim of this study was thus to compare video-oculographic (VOG) features between PD motor subtypes. Methods: Two hundred and four PD patients and 55 age-matched healthy control subjects (HC) were enrolled in this study. PD patients were stratified into PIGD and TD motor subtype groups. VOG amplitude, peak velocity of upward, downward, and vertical saccades, and square wave jerks (SWJ) number and amplitude were compared across groups. Multivariate linear models also investigated associations between VOG parameters and motor severity, gait/balance disturbances, dopaminergic treatment, and cognitive function. Results: The final cohort included 180 PD patients classified as PIGD (n = 121) or TD subtype (n = 59) and 55 HC. Both PD subtypes showed reduced upward and downward amplitude compared to HC, with normal peak velocity. PIGD patients exhibited significantly decreased upward saccadic amplitude compared to TD patients, with no differences in other VOG parameters. Moreover, the upward saccadic amplitude was associated with motor severity, particularly slowness of gait and bradykinesia/rigidity scores, as well as with levodopa equivalent daily dose (LEDD) in the PIGD group. Discussion: This study provides evidence of greater saccadic hypometria in PIGD than in TD patients in upward gaze, contributing to a better understanding of oculomotor impairment in PD. The association of saccadic amplitude with bradykinesia/rigidity severity and LEDD may suggest a role of underlying dopaminergic deficits in ocular dysfunction in PD patients. |
Zhaohuan Ding; Wenbo Ma; Leixiao Feng; Mingsha Zhang; Xiaoli Li Quantifying task-locked information transmission between cortical areas with TMS-EEG Journal Article In: NeuroImage, vol. 317, pp. 1–10, 2025. @article{Ding2025c,Objective: This study aims to develop TMS-EEG (Transcranial magnetic stimulation combined with EEG) technology to detect task-locked neural network activation and dynamically quantify information transmission. Approach: 30 participants performed visually guided gap saccade tasks while TMS-EEG data were recorded, with the TMS pulses delivered to prefrontal cortex (PFC) and posterior parietal cortex (PPC) at different task stages. The directed transfer function (DTF) method was applied to TMS-EEG data to indicate the information flow. By analyzing the channel combinations associated with the PFC and PPC, we calculated differences in information flow within the alpha, beta, and gamma frequency bands to determine whether TMS-EEG could quantitatively characterize the direction of information flow between cortical areas. Main results: Analysis of eye tracker data revealed that all participants successfully performed the saccade task, with a correct rate exceeding 90 %. The mean saccade latency was 132.25 ± 22.59 ms after target appearance. Stimulation of the PFC and PPC revealed significant differences in information flow in the gamma bands at different time points. Specifically, during the preparatory period, the C3 electrode acts as a hub for incoming information from O1, later transitioning to send information towards F4 and O1 post-target. Then, P3 emerges as a hub, sending data towards P4, with connectivity between them intensifying post 100 ms from the target's appearance. Significance: This study utilized DTF values derived from TMS-EEG to characterize information flow between cortical areas during the gap saccade task. This approach provides a novel method for quantifying dynamic changes in connectivity and causality between cortical areas during task processing. |
Yuqing Gu; Yu Li; Lihua Xu; Tianhong Zhang; Huiru Cui; Yanyan Wei; Mengqing Xia; Wenjun Su; Yingying Tang; Xiaochen Tang; Dan Zhang; Xu Liu; Jijun Wang Predictive role of fixation stability for clinical stages and conversion in schizophrenia and its correlation with cognitive function Journal Article In: Schizophrenia Bulletin, pp. 1–10, 2025. @article{Gu2025b,Background and Hypothesis: Given that fixation stability is closely linked to cognition, we investigated fixation stability in patients at different stages of schizophrenia, its relation- ship with cognitive impairments, and its predictive role for conversion to psychosis. Study Design: Fixation stability was measured by bivariate contour ellipse area (BCEA), and cognition was assessed by the Measurement and Treatment Research to Improve Cog- nition in Schizophrenia Consensus Cognitive Battery for 75 patients with first-episode schizophrenia (FES), 75 patients with clinical high-risk (CHR) syndrome, and 75 healthy controls (HCs). After a 1-year longitudinal study, CHR follow-up outcomes were classified as CHR-converters and CHR-nonconverters. Diagnostic model for clinical stages and prediction model for conversion were constructed using logistic regression and Cox regression, respectively. Study Results: Patients exhibited fixation instability and cognition impairments compared to HC, with impairments increasing from CHR to FES. In CHR, BCEA negatively correlated with Measurement and Treatment Research to Improve Cognition in Schizophrenia Consensus Cognitive Battery scores, but this correlation was absent in FES. Diagnostic model effectively discriminated HC and FES, with an area under the receiver-operating characteristic curve of 0.914. Among 66 CHR followed up for 1 year , 13 have converted to schizophrenia, with a conversion rate of 19.70%. When divided into large and small BCEA groups (33 each), the conversion rate was 27.27% and 12.12%. Conversion prediction model achieved an area under the receiver-operating characteristic curve of 0.708. Conclusions: Our results indicate that fixation instability worsens with schizophrenia progression, which is associated with cognitive impairments. Additionally, BCEA may serve as a biomarker for predicting conversion to psychosis. |
Wenbo Ma; Zhaohuan Ding; Leixiao Feng; Xiaoli Li; Mingsha Zhang The role of prefrontal and posterior parietal cortex in generating multiple step saccades Journal Article In: Neuroscience Bulletin, vol. 41, no. 8, pp. 1418–1428, 2025. @article{Ma2025,While multiple step saccades (MSS) are occasionally reported in the healthy population, they are more evident in patients with Parkinson's disease (PD). Therefore, MSS has been suggested as a biological marker for the diagnosis of PD. However, the lack of clarity on the neural mechanism underlying the generation of MSS largely impedes their application in the clinic. We have proposed recently that MSS are triggered by the discrepancy between desired and executed saccades. Accordingly, brain regions involved in saccadic planning and execution might play a role in the generation of MSS. To test this hypothesis, we explored the role of the prefrontal (PFC) and posterior parietal cortex (PPC) in generating MSS by conducting two experiments: electroencephalographic recording and single-pulse transcranial magnetic stimulation in the PFC or PPC of humans while participants were performing a gap saccade task. We found that the PFC and PPC are involved in the generation of MSS. |
Hilary H. T. Ngai; Jingwen Jin Emotion ensemble judgement: Cognitive training for a positive perspective Journal Article In: British Journal of Psychology, vol. 116, no. 3, pp. 636–655, 2025. @article{Ngai2025b,Emotion ensemble judgement refers to the cognitive process by which individuals extract the general emotional tone of a busy visual scene. This study investigated whether emotion ensemble judgement can be changed through cognitive training. Two groups of participants underwent interpretation and visual attention training towards positivity, respectively, while the third group served as the control (total n = 102). All three groups participated in an emotion ensemble-rating task where they rated the overall emotion of a set of facial expressions three times (pre-training, immediately post-training and 7-days post-training). The results demonstrated the malleability of perceptual judgement of an emotion ensemble. The interpretation-training group exhibited a shift towards positivity, particularly for fearful ensembles. Similarly, the attention-training group also showed a positive shift, along with increased eye movements towards happy stimuli immediately after training. These findings help shed light on the formation and correction of biases in emotion perception and judgement. |
Zeynep G. Özkan; Jukka Hyönä; Maria Fernández-López; Manuel Perea How does vertical reading affect saccade programming and lexical processing in the Roman script? Journal Article In: Psychological Research, vol. 89, no. 4, pp. 1–10, 2025. @article{Oezkan2025,Although computational models of eye movement control in reading have focused on horizontal text layouts, vertically oriented text is also encountered in daily life in the Roman script. To examine the interplay between saccade programming and lexical processing under vertical reading in the Roman script, we manipulated (1) the layout of words in a sentence (horizontal vs. vertical) and (2) word frequency (high vs. low). In the vertical layout, the words themselves remained in standard orientation but were arranged vertically (one below the other). Eye-movement measures at the sentence level (e.g., total reading time, number of fixations) showed a cost for the vertical arrangement, primarily reflected in longer fixation durations rather than a greater number of fixations. Critically, at the target-word level, the word-frequency effect —which increased in later eye-fixation measures (gaze duration, total time)— remained similar in size across both layouts. The additive pattern of word frequency and text layout, supported by Bayes factors, suggests that slower saccade programming in the vertical format does not substantially impact lexical processing. While lexical processing can influence saccade programming, delays in saccade programming do not, in turn, alter lexical processing—a pattern that constrains current models of eye movement control in reading. |
Flavio Jean Schmidig; Daniel Yamin; Omer Sharon; Yoav Nadu; Jonathan Nir; Charan Ranganath; Yuval Nir Anticipatory eye gaze as a marker of memory Journal Article In: Communications Psychology, vol. 3, no. 1, pp. 1–14, 2025. @article{Schmidig2025,Human memory is typically studied by direct questioning, and the recollection of events is investigated through verbal reports. Thus, current research confounds memory per-se with its report. Critically, the ability to investigate memory retrieval in populations with deficient verbal ability is limited. Here, using the MEGA (Memory Episode Gaze Anticipation) paradigm, we show that monitoring anticipatory gaze using eye tracking can quantify memory retrieval without verbal report. Upon repeated viewing of movie clips, eye gaze patterns anticipating salient events can quantify their memory traces seconds before these events appear on the screen. A series of five experiments with a total of 145 participants using either tailor-made animations or naturalistic movies consistently reveal that accumulated gaze proximity to the event can index memory. Machine learning-based classification can identify whether a given viewing is associated with memory for the event based on single-trial data of gaze features. Detailed comparison to verbal reports establishes that anticipatory gaze marks recollection of associative memory about the event, whereas pupil dilation captures familiarity. Finally, anticipatory gaze reveals beneficial effects of sleep on memory retrieval without verbal report, illustrating its broad applicability across cognitive research and clinical domains. Anticipatory eye movements during repeated movie viewing reveal when and what is remembered. Gaze patterns correlate with explicit reports, offering a method to detect memory for events without verbal reports. |
Eduardo Cunha Vilela; Joao Lucas Bernardy; Gerson Yukio Tomanari Eye fixations in delayed matching-to-sample task as predictors of stimuli class formation in MTS tasks Journal Article In: Learning and Motivation, vol. 91, pp. 1–12, 2025. @article{Vilela2025,This study examined whether eye fixation duration on sample stimuli predicts success in equivalence class formation during matching-to-sample (MTS) tasks with varying delays. Nine typically developing adults completed conditional discrimination training using a one-to-many (OTM) structure to establish four three-member equivalence classes. Each class was trained under a different delay condition: simultaneous MTS, 0-s, 2-s, or 4-s delays between sample offset and comparison onset. Eye movements were recorded throughout training to assess observing behavior. Seven participants met the learning criterion and demonstrated equivalence class formation. The delay condition did not significantly affect the acquisition or emergence of equivalence or symmetry relations. Similarly, sample fixation durations did not significantly differ across delay conditions. However, fixation durations were longer in early training blocks, suggesting a practice effect. A strong positive correlation between sample response latency and fixation duration also emerged, supporting the interpretation that latency may reflect engagement time. These findings challenge the view that increased delay intervals inherently enhance learning by extending sample observation and instead highlight the value of direct eye-tracking measures in understanding observing behavior and its relation to stimulus control. |
Lihi Goldman; Dana Basel; Hadar Hallel; Nimrod Hertz-Palmor; Amit Lazarov Instant messaging communication in social anxiety: No support for the Combined Cognitive Bias Hypothesis (CCBH) Journal Article In: Motivation and Emotion, vol. 49, no. 4, pp. 439–454, 2025. @article{Goldman2025,The Combined Cognitive Bias Hypothesis (CCBH) postulates that attention and interpretation biases do not work in “solitary,” but nourish each other, interacting in a cyclic or bi-directional manner. While providing initial evidence for the CCBH in social anxiety, most research assessed each bias separately using traditional laboratory-based tasks with different stimuli in each task. Here, we examined the CCBH, assessing both biases within a single ecological-valid task. We hypothesized that compared with control participants, socially anxious participants would interpret ambiguity more negatively and would also attend more to ambiguous (negatively interpreted) information. Participants with high (HAS; n = 30) and low (LSA; n = 30) levels of social anxiety read a fictitious textual conversation (via the WhatsApp instant messaging platform) between two students following their first date, while putting themselves in the shoes of the conversation initiator. The textual conversation featured both ambiguous and irrelevant (hence non-ambiguous) sections regarding the interest of the counterpart to proceed to another date. Participants' interpretation of each section was evaluated, as was their attention allocation to each section using eye-tracking methodology. No group differences emerged on interpretation of the ambiguous and irrelevant sections– both groups rated the former as more negative than the latter. Conversely, in attention, while LSA participants dwelled longer on the ambiguous (negatively-interpreted) sections, compared to the irrelevant (less negatively-interpreted) ones, HSA participants exhibited the opposite pattern of attention allocation. No evidence emerged for the CCBH in social anxiety when explored within a single ecological-valid task gauging both interpretation and attention. |
Sajjad Karimi; Masoud Nateghi; Gabriela I. Cestero; Lina Chitadze; Deepanshi; Yi Yang; Juhee H. Vyas; Chuoqi Chen; Zeineb Bouzid; Cem O. Yaldiz; Nicholas Harris; Rachel Bull; Bradly T. Stone; Spencer K. Lynn; Bethany K. Bracken; Omer T. Inan; J. Douglas Bremner; Reza Sameni Prescreening depression using wearable electrocardiogram and photoplethysmogram data from a psycholinguistic experiment Journal Article In: Physiological Measurement, vol. 46, no. 8, pp. 1–20, 2025. @article{Karimi2025,Objective. Depression is a prevalent mental health disorder that significantly impacts well-being and quality of life. This study investigates the relationship between depression and cardiovascular function, exploring time-series features derived from electrocardiogram (ECG) and photoplethysmogram (PPG) data as potential biomarkers for depression prescreening. Approach. As part of a comprehensive psycholinguistic experiment, we collected data from 60 individuals, including both healthy participants and those with varying levels of depression, assessed using the Beck Depression Inventory-II (BDI-II) and the Patient Health Questionnaire-9 (PHQ-9). Bimodal features derived from both ECG and PPG data were used to develop machine learning models for depression risk classification, employing classifiers such as random forest, XGBoost, logistic regression, and support vector machines (SVMs). Additionally, regression models were built to predict depression severity based on ECG- and PPG-derived biomarkers. Main results. Key findings indicate that short-term variability (SD1) features in the ECG RR interval, peripheral systolic and diastolic phases from the PPG, and pulse duration significantly differ between healthy individuals and those at risk of depression. SVM achieved the best classification performance, with an area under the ROC curve of 0.83 ± 0.11 for BDI-II-based classification and 0.78 ± 0.11 for PHQ-9-based classification. SHapley Additive exPlanations analysis consistently identified systolic-SD1 and RR-SD1 as key predictors. Regression analysis further supported the role of cardiovascular features in assessing depression severity, yielding a mean absolute error of 10.18 for BDI-II and 5.27 for PHQ-9 score regression. Significance. This study demonstrates the feasibility of using wearable ECG and PPG technologies for depression prescreening. The findings suggest that cardiac activity-based biomarkers can contribute to the development of cost-effective, objective, and non-invasive tools for mental health assessment, complementing traditional diagnostic methods. |
Philipp J. Koch; Tabea Kürten; Anja Fellbrich; Andreas Sprenger; Christoph Helmchen 2025. @misc{Koch2025,This case study illustrates object tilt illusions without room tilt illusions which may be related to impairments of reference frames of visual perception as we did not find evidence by clinical, behavioral and brain imaging analyses that support lesions or disconnections of core vestibular processing areas as it is postulated in room tilt illusion. As perceived tilts were only found in distant but not near objects and noticed without any tilt perception of one' own body a visual illusion within the extrapersonal space might be a feasible mechanism facilitated by the inter- and intrahemispheric occipito-parietal disconnections demonstrated by modern disconnectivity analyses. As a consequence, information on the visual representation of objects in space may not properly be matched between both hemispheres (due to the severe disconnection in the splenium) leading not only to object distorsions and metamorphopsia but also object tilt illusions. |
Yumo Li; Qiandong Wang; Siqi Yuan; Tak Kwan Lam; Kun Guo; Yong Q. Zhang; Li Yi Reduced attention to human eyes in autism-associated Shank3 mutant laboratory beagle dogs Journal Article In: Molecular Psychiatry, vol. 30, no. 8, pp. 3765–3773, 2025. @article{Li2025r,Autistic individuals often exhibit reduced attention to faces and eyes, which may underlie their social difficulty. This study used eye-tracking techniques to explore visual attention towards faces in Shank3 mutant laboratory beagle dogs, a model for autism, to identify parallels with human autism. We first assessed visual attention differences towards the eyes between Shank3 mutant and wild-type (WT) laboratory beagles by presenting them with human and dog face images. Then, using the gaze cueing paradigm, we directed the dogs' gaze towards the eyes and mouth and quantified their gaze shifts. Finally, we investigated the impact of oxytocin on eye-gaze behavior by comparing gaze patterns under pre-administration, vehicle, and oxytocin conditions while viewing human faces. We found that mutant dogs showed a reduced proportional viewing time of human eyes than WT dogs (p = 0.032), but no difference in proportional eye viewing time when viewing dog faces (p = 0.691). Mutant dogs shifted their gazes away from the human eyes more quickly than the mouth (p = 0.043), unlike WT dogs (p = 0.345), suggesting an active eye avoidance. Furthermore, exogenous oxytocin increased proportional viewing time on human eyes in mutant dogs than pre-administration and vehicle conditions (p = 0.022), suggesting a potential effect of oxytocin on social attention in autism. To our knowledge, this study is the first to report an eye avoidance phenotype in an animal model of autism. These findings contribute to our understanding of the mechanisms underlying social difficulties in autism and the development of supporting strategies for autism. |
Hartmut Meister; Moritz Wächtler; Pascale Sandmann; Ruth Lang-Roth; Khaled H. A. Abdel-Latif Audiovisual perception of sentence stress in cochlear implant recipients Journal Article In: Audiology Research, vol. 15, no. 4, pp. 1–27, 2025. @article{Meister2025,Background/Objectives: Sentence stress as part of linguistic prosody plays an important role for verbal communication. It emphasizes particularly important words in a phrase and is reflected by acoustic cues such as the voice fundamental frequency. However, visual cues, especially facial movements, are also important for sentence stress perception. Since cochlear implant (CI) recipients are limited in their use of acoustic prosody cues, the question arises as to what extent they are able to exploit visual features. Methods: Virtual characters were used to provide highly realistic but controllable stimuli for investigating sentence stress in groups of experienced CI recipients and typical-hearing (TH) peers. In addition to the proportion of correctly identified stressed words, task load was assessed via reaction times (RTs) and task-evoked pupil dilation (TEPD), and visual attention was estimated via eye tracking. Experiment 1 considered congruent combinations of auditory and visual cues, while Experiment 2 presented incongruent stimuli. Results: In Experiment 1, CI users and TH participants performed similarly in the congruent audiovisual condition, while the former were better at using visual cues. RTs were generally faster in the AV condition, whereas TEPD revealed a more detailed picture, with TH subjects showing greater pupil dilation in the visual condition. The incongruent stimuli in Experiment 2 showed that modality use varied individually among CI recipients, while TH participants relied primarily on auditory cues. Conclusions: Visual cues are generally useful for perceiving sentence stress. As a group, CI users are better at using facial cues than their TH peers. However, CI users show individual differences in the reliability of the various cues. |
Katherine Rowley; Eva Gutierrez-Sigut; Mairéad MacSweeney; Gabriella Vigliocco Reading with deaf eyes: Automatic activation of speech-based phonology during word recognition is task dependent Journal Article In: PLoS ONE, vol. 20, no. 8, pp. 1–27, 2025. @article{Rowley2025,Literacy levels are highly variable within the deaf population and, compared to the general population, on average, reading levels are lower. As speech-based phonological coding is a known predictor of reading success in hearing individuals, much research has focussed on deaf readers' processing of speech-based phonological codes during word recognition and reading as a possible explanation for the widespread reading difficulties in the deaf population. Although results are mixed, there is recent growing evidence that deaf and hearing readers process speech-based phonological codes differently. Furthermore, some studies indicate that phonological ability may not be a strong correlate of literacy skills in deaf, adult readers. Here, we investigate orthographic, semantic, and phonological processing during single word reading in deaf (N = 20) and hearing (N = 20) adult readers, who were matched on reading level. Specifically, we tracked deaf and hearing readers' eye-movements using an adaptation of the visual world paradigm using written words and pictures. We found that deaf and hearing readers activate orthographic and semantic information following a similar time-course. However, there were differences in the way the groups processed phonology, with deaf readers making less use of phonological information. Crucially, as both groups were matched for reading level, reduced phonological processing did not appear to impact reading skill in deaf readers. |
Giacomo Scanavini; Isabelle Martin; Ludvik Alkhoury; Ana Radanovic; Yakira Tepler; Abhishek Jaywant; N. Jeremy Hill; Tracy Butler; Keith W. Jamison; Amy Kuceyeski; Nicholas D. Schiff; Sudhin A. Shah Coupling of event-related potential and pupil dilation as a compensatory marker of executive attention in traumatic brain injury Journal Article In: Neurotrauma Reports, vol. 6, no. 1, pp. 706–719, 2025. @article{Scanavini2025,Traumatic brain injury (TBI) impairs attention and executive function, often through disrupted coordination between cognitive and autonomic systems. While electroencephalography (EEG) and pupillometry are widely used to assess neural and autonomic responses independently, little is known about how these systems interact in TBI. Understanding their coordination is essential to identify compensatory mechanisms that may support attention under conditions of neural inefficiency. In this study, we examined pupil dilation during the Attention Network Test in individuals with TBI (n = 25) and controls without brain injury (n = 45). TBI participants exhibited preserved accuracy but slower reaction times (RTs), suggesting increased cognitive effort. Paradoxically, this effort was not reflected in heightened pupil dilation. Instead, pupil responses were attenuated, suggesting impaired recruitment of the locus coeruleus-norepinephrine system and possible autonomic dysregulation. We further assessed the relationship between simultaneously recorded pupillary responses and visual evoked responses in a subset of those in whom both measures were available (n = 23, TBI; n = 35, controls). Crucially, while both pupil dilation and amplitude of the visual P3 event-related potential were reduced in TBI, these measures showed a positive correlation across participants with TBI; this was absent in controls. Our results suggest that TBI may induce a compensatory coupling between cortical and autonomic systems to sustain cognitive performance despite underlying dysfunction. Positive correlation between pupil dilation and event-related potential suggest a role for arousal dysregulation in subjects with TBI. Our findings provide new evidence for altered EEG-pupil dynamics in TBI and highlight the potential of combining cortical and autonomic measures as a multimodal biomarker for tracking recovery, stratifying injury severity, and guiding individualized rehabilitation strategies. |
Wendy Sun; Anne Billot; Jingnan Du; Xiangyu Wei; Rachel A. Lemley; Mohammad Daneshzand; Aapo Nummenmaa; Randy L. Buckner; Mark C. Eldaief Precision network modeling of transcranial magnetic stimulation across individuals suggests therapeutic targets and potential for improvement Journal Article In: Human Brain Mapping, vol. 46, no. 11, pp. 1–23, 2025. @article{Sun2025,Higher-order cognitive and affective functions are supported by large-scale networks in the brain. Dysfunction in different networks is proposed to associate with distinct symptoms in neuropsychiatric disorders. However, the specific networks targeted by current clinical transcranial magnetic stimulation (TMS) approaches are unclear. While standard-of-care TMS relies on scalp-based landmarks, recent FDA-approved TMS protocols use individualized functional connectivity with the subgenual anterior cingulate cortex (sgACC) to optimize TMS targeting. Leveraging previous work on precision network estimation and modeling of the TMS electric field (E-field), we asked whether various clinical TMS approaches target different functional networks between individuals. Results revealed that modeled homotopic scalp positions (left F3 and right F4) target different networks within and across individuals, and right F4 generally favors a right-lateralized control network. TMS coil positions over the dorsolateral prefrontal cortex (dlPFC) zone anticorrelated with the sgACC most frequently target a network coupled to the ventral striatum (reward circuitry) but largely miss that network in some individuals. We further illustrate how modeling can be used to retrospectively assess the estimated targets achieved in prior TMS sessions and also used to prospectively provide coil positions that can target distinct closely localized dlPFC network regions with spatial selectivity and maximal E-field intensity. In a final study, precision targeting was found to be feasible in participants with Major Depressive Disorder using data derived from a single low-burden MRI session suggesting the methods are applicable to translational efforts where limiting patient burden and ensuring robustness are critical. |
Bernhard Angele; Zeynep Gunes Ozkan; Marina Serrano-Carot; Jon Andoni Duñabeitia How low can you go? Tracking eye movements during reading at different sampling rates Journal Article In: Behavior Research Methods, vol. 57, no. 7, pp. 1–25, 2025. @article{Angele2025,Eye-movement research has revolutionized our understanding of reading, but the use of eye-tracking techniques in investigating the reading process is still limited by the cost of high-precision eye-tracking, which limits research to laboratories with sufficient resources. It is important to evaluate to what extent cognitive processes during reading can be measured with less expensive eye-tracking devices. One such way may be to use devices with a lower sampling rate, which are much less expensive than high-sampling rate eye-trackers. We recorded readers' eye movements during reading at different sampling rates and show that it is possible to measure the classic effect of word frequency on fixation duration, reflecting ongoing cognitive processing during reading, at sampling rates ranging from 250 to 2000 Hz. We simulate even lower sampling rates and show that, with a sufficiently large sample size, it is possible to detect the effect of word frequency even at very low sampling rates (30–125 Hz). Our results demonstrate that, in principle, low sampling rates are not an obstacle to studying the effects of cognitive processing during reading. |
Mellisa Boyle; Barry Dauphin; Harold H. Greene; Mindee Juve; Ellen Day-Suba Eye movements during pareidolia: Exploring biomarkers for thinking and perception problems on the Rorschach Journal Article In: Journal of Eye Movement Research, vol. 18, no. 4, pp. 1–12, 2025. @article{Boyle2025,Eye movements (EMs) offer valuable insights into cognitive and perceptual processes, serving as potential biomarkers for disordered thinking. This study explores the relationship between EM indices and perception and thinking problems in the Rorschach Performance Assessment System (R-PAS). Sixty non-clinical participants underwent eye-tracking while completing the Rorschach test, focusing on variables from the Perception and Thinking Problems Domain (e.g., WSumCog, SevCog, FQo%). The results reveal that increased cognitive disturbances were associated with greater exploratory activity but reduced processing efficiency. Regression analyses highlighted the strong predictive role of cognitive variables (e.g., WSumCog) over perceptual ones (e.g., FQo%). Minimal overlap was observed between performance-based (R-PAS) and self-report measures (BSI), underscoring the need for multi-method approaches. The findings suggest that EM patterns could serve as biomarkers for early detection and intervention, offering a foundation for future research on psychotic-spectrum processes in clinical and non-clinical populations. |
Rika Etteldorf; Annabell Coors; Santiago Estrada; Monique M. B. Breteler; Ulrich Ettinger Regional brain volume and cortical thickness mediate age-related differences in eye movement control Journal Article In: The Journals of Gerontology, Series B: Psychological Sciences and Social Sciences, vol. 80, no. 7, pp. 1–12, 2025. @article{Etteldorf2025,Objectives: Eye movements (EMs) are considered biomarkers for age-related neurological or psychological deficits, and oculomotor control has been shown to strongly decline with age. This study aimed to understand the neural pathways of these age-related changes. Methods The analysis was based on 5,400 participants (aged 30-95 years) from the population-based Rhineland Study. EMs were recorded using video-based infrared oculography at 1,000 Hz. Brain structure measures were obtained from T1-weighted MR images using FreeSurfer. Relations of brain structure with EM outcomes were quantified using multivariable linear regression models while adjusting for age, sex, educational level, and best-corrected visual acuity. Brain structure measures were further analyzed as potential mediators in the relation between age and EM outcomes. Results: Larger volumes of the globus pallidus and thalamus were associated with shorter saccadic latencies. Thicker cortex in frontal and parietal brain regions was associated with fewer direction errors in the antisaccade task in female but not in male participants. Thicker cortex in the calcarine sulcus was associated with better smooth pursuit performance. Cerebellar gray and white matter volumes were associated with better performance on the antisaccade and smooth pursuit tasks. Mediation analyses suggested that age-related differences in brain structures explain up to 18% of age-related differences in oculomotor performance. Discussion: Our findings extend previous studies by identifying novel brain structural correlates of EM performance and quantifying the extent to which they explain age-related differences in EM performance. Our results show that differences in brain structure partly account for age-related differences in EM performance. |
Katarzyna Harezlak; Ewa Pluciennik Towards improved eye movement biometrics: Investigating new features with neural networks Journal Article In: Sensors, vol. 25, no. 14, pp. 1–16, 2025. @article{Harezlak2025,Providing protected access to many everyday-used resources is becoming increasingly necessary. Research on applying eye movement for this purpose has been conducted for many years. However, due to technological advancements and the lack of stable solutions, subsequent explorations remain valid. The presented work is one of such studies. Two methods of biometric identification based on eye movements that utilize neural networks have been developed. In the first case, a feature vector was constructed from a 100-element time series depicting eye movement dynamics, which included velocity, acceleration, jerk, their point-to-point percentage changes, and frequency-domain representations. The same eye movement dynamic features were used in the second method, but this time, statistical values were calculated based on the previously defined time series. Long Short-Term Memory (LSTM) and dense networks were used in the user identification task in the first and second approaches, respectively. In the exploration, the publicly available GazeBase dataset was used, from which data collected for the ‘jumping point' stimulus were chosen. The obtained results are very promising, with an accuracy of 96% for the LSTM model and the time series feature vector set and 76% for the second method. They were achieved over a three-year time span of eye movement recordings; however, different time periods were investigated, as well as various numbers of stimulus positions. |
Yinglin Leng; Hong Zhou; Luhua Wei; Yanyan Jiang; Xia Wang; Yunchuang Sun; Fan Li; Jing Chen; Wei Sun; Wei Wang; Lin Zhang; Guiping Zhao; Zhaoxia Wang Follow-up observation of eye movements in multiple system atrophy and Parkinson's disease: A cohort study Journal Article In: BMJ Open, vol. 15, no. 7, pp. 1–8, 2025. @article{Leng2025,Objectives We aimed to explore the changes in oculomotor deficiencies during the follow-up of patients with multiple system atrophy (MSA) and Parkinson's disease (PD), and to investigate the value of dynamic eye movement examination in their differential diagnosis. Design This was a cohort study conducted from 2017 to 2023. Setting The Movement Disorders Clinic at a tertiary hospital in Beijing, China. Participants 56 patients with PD and 13 patients with MSA from an initial cohort of over 1100 with parkinsonism were included in the final longitudinal analysis. Outcome measures Multisystem evaluations were performed at baseline. Videonystagmography (VNG) was repeated to assess oculomotor dysfunction at baseline and during follow-up. Abnormalities in the fixation and gaze-holding test, without-fixation test, reflexive and memory-guided saccade tests, smooth pursuit test and optokinetic test were qualitatively and quantitatively recorded and statistically analysed. Results The median follow-up time of MSA (16 months) was significantly shorter than that of PD (27 months). In MSA, the incidence of abnormalities in fixation and gaze-holding tests (0% vs 30.8% |
Max Levinson; Christopher C. Pack; Sylvain Baillet Stimulus-dependent delay of perceptual filling-in by microsaccades Journal Article In: Journal of vision, vol. 25, no. 8, pp. 1–14, 2025. @article{Levinson2025,Perception is a function of both stimulus features and active sensory sampling. The illusion of perceptual filling-in occurs when eye gaze is kept still: visual boundary perception may fail, causing adjacent visual features to remarkably merge into one uniform visual surface. Microsaccades-small, involuntary eye movements during gaze fixation-counteract perceptual filling-in, but the mechanisms underlying this process are not well-understood. We investigated whether microsaccade efficacy for preventing filling-in depends on two boundary properties, namely, color contrast and retinal eccentricity (distance from gaze center). Twenty-one human participants (male and female) fixated on a point until they experienced filling-in between two isoluminant colored surfaces. We found that increased color contrast independently extends the duration before filling-in, but does not alter the impact of individual microsaccades. Conversely, lower eccentricity delayed filling-in only by increasing microsaccade efficacy. We propose that microsaccades facilitate stable boundary perception via a transient retinal motion signal that scales with eccentricity but is invariant to boundary contrast. These results shed light on how incessant eye movements integrate with ongoing stimulus processing to stabilize perceptual detail, with implications for visual rehabilitation and the optimization of visual presentations in virtual and augmented reality environments. |
Cristina Rovira-Gay; Marc Argiles; Clara Mestre; Marta Masdemont-Isern; Jaume Pujol Objective evaluation of fusional vergence after a vision therapy protocol in typical binocular vision Journal Article In: Ophthalmic and Physiological Optics, vol. 45, no. 5, pp. 1173–1185, 2025. @article{Rovira-Gay2025,Introduction: Vision therapy is an effective treatment option for binocular vision and accommodative anomalies. However, its effect on typical binocular vision is less documented. The aim of this study was to evaluate objectively the change in near fusional vergence amplitudes in adults with typical binocular vision after performing a vision therapy protocol. Methods: Thirty-four adults were randomly classified into an experimental group (EG), who underwent a vision therapy protocol for 12 weeks, and a control group (CG), who received a placebo treatment for 12 weeks (Phase 1). In Phase 2, the CG performed the same therapy protocol as the EG. Fusional vergence amplitudes were measured objectively in a haploscopic set-up using smooth and step fusional vergence tests. The break points of positive and negative fusional vergence (PFV and NFV, respectively) were determined using a custom algorithm. Results: After Phase 1, there were no significant differences between the groups for fusional vergences. After Phase 2, PFV and NFV increased significantly as measured with the smooth and step tests (p = 0.002 and p < 0.001 for NFV and p = 0.03 and p = 0.02 for PFV, respectively). These improvements were maintained after 1 month without any further intervention (all p > 0.05). Conclusion: Based on these results, clinicians should consider that the vergence system cannot be trained beyond 2 and 5 Δ for NFV and PFV, respectively, when aiming to enhance vergence skills with vision therapy in patients without binocular dysfunctions. |
Vanteemar S. Sreeraj; H. V. Raghuram; Swarna Buddha Nayok; Aditi Subramaniam; Harleen Chhabra; Gaurav Bhalerao; Anushree Bose; Sri Mahaveer Agarwal; Sunil Kalmady; Venkataram Shivakumar; Samuel B. Hutton; Ganesan Venkatasubramanian Fixation task: A simple eye movement task reveals an impairment in schizophrenia Journal Article In: Schizophrenia Bulletin, pp. 1–10, 2025. @article{Sreeraj2025,Background: Fixation stability (FS) is a basic substrate of visuomotor processing that can be assessed by tracking eye movements during a simple, easy-to-perform task of gazing at a visual stimulus. We studied FS with and without distractors for its potential as an endophenotype marker in antipsychotic-naïve/free schizophrenia (SCZ), SCZ first-degree relatives (FDRs), and healthy controls (HC). Method: Monocular high-frequency eye tracking data were recorded during a fixation stability task in 69 antipsychotic- naïve/free SCZ, 49 FDRs, and 76 HCs. The task required maintenance of gaze on a central circular target while ignoring an identical peripheral distractor, when present, at near/farther distances on either side. Fixation stability across the groups and the effect of laterality and distance of the distractor effect were analyzed using ANCOVA and RMANCOVA. Result: SCZ had significantly higher fixation frequency, saccade amplitude, and scanpath length compared to the other groups, even in trials without distractors (ηp 2 = 0.05– 0.07). Introducing distractors resulted in further worsening of performance in SCZ (ηp 2 = 0.09–0.23). First-degree relatives showed impairment in median fixation duration (ηp 2 = 0.13). Higher saccade amplitudes and scanpath lengths (both ηp 2 = 0.09) were noted in trials with farther distractors across the groups. A significant interaction effect of the laterality * group was noted on scanpath length (ηp 2 = 0.03). Discussion: FS impairment was noted in antipsychotic naïve/free SCZ, and it worsened with the introduction of distractors. An inversed laterality effect (rightward-bias) of distractor was noted in SCZ and their FDRs, suggesting a possible association of attenuation/reversal of visual func- tional asymmetry with SCZ vulnerability. Future studies should evaluate FS as illness markers across different clin- ical stages. Key |
Isla Williams; Andrea Phillipou; Elsdon Storey; Peter Brotchie; Larry Abel Visual perception and fixation patterns in an individual with ventral simultanagnosia, integrative agnosia and bilateral visual field loss Journal Article In: Neurology International, vol. 17, no. 7, pp. 1–17, 2025. @article{Williams2025,Background/Objectives: As high-acuity vision is limited to a very small visual angle, examination of a scene requires multiple fixations. Simultanagnosia, a disorder wherein elements of a scene can be perceived correctly but cannot be integrated into a coherent whole, has been parsed into dorsal and ventral forms. In ventral simultanagnosia, limited visual integration is possible. This case study was the first to record gaze during the presentation of a series of visual stimuli, which required the processing of local and global elements. We hypothesised that gaze patterns would differ with successful processing and that feature integration could be disrupted by distractors. Methods: The patient received a neuropsychological assessment and underwent CT and MRI. Eye movements were recorded during the following tasks: (1) famous face identification, (2) facial emotion recognition, (3) identification of Ishihara colour plates, and (4) identification of both local and global letters in Navon composite letters, presented either alone or surrounded by filled black circles, which we hypothesised would impair global processing by disrupting fixation. Results: The patients identified no famous faces but scanned them qualitatively normally. The only emotion to be consistently recognised was happiness, whose scanpath differed from the other emotions. She identified none of the Ishihara plates, although her colour vision was normal on the FM-15, even mapping an unseen digit with fixations and tracing it with her finger. For plain Navon figures, she correctly identified 20/20 local and global letters; for the “dotted” figures, she was correct 19/20 times for local letters and 0/20 for global letters (chi-squared NS for local, p < 0.0001, global), with similar fixation of salient elements for both. Conclusions: Contrary to our hypothesis, gaze behaviour was largely independent of the ability to process global stimuli, showing for the first time that normal acquisition of visual information did not ensure its integration into a percept. The core defect lay in processing, not acquisition. In the novel Navon task, adding distractors abolished feature integration without affecting the fixation of the salient elements, confirming for the first time that distractors could disrupt the processing, not the acquisition, of visual information in this disorder. |
Atsushi Yoshida; Okihide Hikosaka Contribution of glutamatergic projections to neurons in the nonhuman primate substantia nigra pars reticulata for reactive inhibition Journal Article In: PNAS, vol. 122, no. 26, pp. 1–11, 2025. @article{Yoshida2025,The basal ganglia play a crucial role in action selection by facilitating desired movements and suppressing unwanted ones. The substantia nigra pars reticulata (SNr), a key output nucleus, facilitates movement through disinhibition of the superior colliculus (SC). However, its role in action suppression, particularly in primates, remains less clear. We investigated whether individual SNr neurons in three male macaque monkeys bidirectionally modulate their activity to both facilitate and suppress actions and examined the role of glutamatergic inputs in suppression. Monkeys performed a sequential choice task, selecting or rejecting visually presented targets. Electrophysiological recordings showed that SNr neurons decreased firing rates during target selection and increased firing rates during rejection, demonstrating bidirectional modulation. Pharmacological blockade of glutamatergic inputs to the lateral SNr disrupted saccadic control and impaired suppression of reflexive saccades, providing causal evidence for the role of excitatory input in behavioral inhibition. These findings suggest that glutamatergic projections, potentially originating from sources including the subthalamic nucleus, contribute to the increased SNr activity during action suppression. Our results highlight conserved basal ganglia mechanisms across species and offer insights into the neural substrates of action selection and suppression in primates, with implications for understanding disorders such as Parkinson's disease. |
Dan Zhang; Chunyan Ma; Lihua Xu; Xu Liu; Huiru Cui; Yanyan Wei; Wensi Zheng; Yawen Hong; Yuou Xie; Zhenying Qian; Yegang Hu; Yingying Tang; Chunbo Li; Zhi Liu; Tao Chen; Haichun Liu; Tianhong Zhang; Jijun Wang Abnormal scanning patterns based on eye movement entropy in early psychosis Journal Article In: Biological Psychiatry: Cognitive Neuroscience and Neuroimaging, vol. 10, no. 7, pp. 718–725, 2025. @article{Zhang2025b,Background: Restricted scan path mode is hypothesized to explain abnormal scanning patterns in patients with schizophrenia. Here, we calculated entropy scores (drawing on gaze data to measure the statistical randomness of eye movements) to quantify how strategical and random participants were when processing image stimuli. Methods: Eighty-six patients with first-episode schizophrenia (FES), 124 individuals at clinical high risk (CHR) for psychosis, and 115 healthy control participants (HCs) completed an eye-tracking examination while freely viewing 35 static images (each presented for 10 seconds) and cognitive assessments. We compared group differences in the overall entropy score, as well as entropy scores under various conditions. We also investigated the correlations between entropy scores and symptoms and cognitive function. Results: Increased overall entropy scores were noted in the FES and CHR groups compared with the HC group, and these differences were already apparent within 0 to 2.5 seconds. In addition, the CHR group exhibited higher entropy than the HC group when viewing low-meaning images. Moreover, the entropy within 0 to 2.5 seconds showed significant correlations with negative symptoms in the FES group, attention/vigilance scores in the CHR group, and speed of processing and attention/vigilance scores across all 3 groups. Conclusions: The results indicate that individuals with FES and those at CHR scanned pictures more randomly and less strategically than HCs. These patterns also correlated with clinical symptoms and neurocognition. The current study highlights the potential of the eye movement entropy measure as a neurophysiological marker for early psychosis. |
Gancheng Zhu; Zehao Huang; Xiaoting Duan; Shuai Zhang; Rong Wang; Yongkai Li; Zhiguo Wang Smartphone eye-tracking with deep learning: Data quality and field testing Journal Article In: Behavior Research Methods, vol. 57, no. 7, pp. 1–19, 2025. @article{Zhu2025b,Eye-tracking is widely used to measure human attention in research, commercial, and clinical applications. With the rapid advancements in artificial intelligence and mobile computing, deep learning algorithms for computer vision-based eye tracking have become feasible for smartphones. This paper presents a real-time smartphone eye-tracking system built upon a deep neural network trained on a dataset of 7.4 million facial images. The tracking performance of the system was benchmarked against an industrial gold-standard EyeLink eye tracker using a reasonably large sample (N = 32). The benchmark test showed that, while the smartphone eye-tracking system was less precise (0.177° vs. 0.028°), its tracking accuracy was comparable to the EyeLink tracker (1.32° vs. 1.20°). To evaluate whether the smartphone eye-tracking system is sensitive enough for real-world application, a field test involving 98 volunteers assessed depressive symptoms using three simple visual tasks on a smartphone: fixation stability, free-viewing, and smooth pursuit. The results showed that using the smartphone eye-tracking system can achieve an accuracy of 76.67% in predicting depressive symptoms. These results demonstrate that smartphone eye-tracking can deliver quality data and has potential in scientific and clinical applications. |
Michele Bevilacqua; Fabienne Windel; Elena Beanato; Pauline Menoud; Sarah Zandvliet; Nicola Ramdass; Lisa Fleury; Julie Hervé; Krystel R. Huxlin; Friedhelm C. Hummel; Estelle Raffin Pathway-dependent brain stimulation responses indicate motion processing integrity after stroke Journal Article In: Brain, vol. 148, no. 7, pp. 2361–2372, 2025. @article{Bevilacqua2025,Homonymous hemianopia (HH), a common visual impairment resulting from occipital lobe lesions, affects a significant number of stroke survivors. Intensive perceptual training can foster recovery, possibly by enhancing surviving visual pathways. This study employed cortico-cortical paired associative stimulation (ccPAS) to induce associative plasticity within the residual and bidirectional primary visual cortex (V1)-middle temporal area (MT) pathways in stroke patients. We used ccPAS, which is thought to tap into Hebbian-like spike-timing dependent plasticity, over a motion processing pathway in stroke patients to transiently improve visual motion discrimination in their blind field. Sixteen stroke patients participated in this double-blind, crossover study comparing the effects of bidirectional ccPAS (V1-to-MT or MT-to-V1) on motion discrimination and EEG-Granger Causality. Additionally, we explored potential multimodal sources of inter-individual variability. Results showed that MT-to-V1 ccPAS enhanced motion direction discrimination, but the expected electrophysiological increase in top-down MT-to-V1 inputs was observed only in patients who showed improvement in motion discrimination. Good responders to MT-V1 ccPAS also demonstrated improved functional coupling between the cortical motion pathway and other relevant areas in the visual network, as well as more preserved ipsilesional V1-MT structural integrity. These findings indicate that targeted ccPAS can effectively engage functionally relevant residual visual pathways in stroke-affected brains, potentially offering new avenues for patient stratification and visual recovery strategies. |
Dario Cazzoli; Brigitte C. Kaufmann; Henrik Rühe; Nora Geiser; Thomas Nyffeler Incidence of visuospatial neglect in acute stroke: Assessment and stroke characteristics in an unselected 1-year cohort Journal Article In: Stroke, vol. 56, no. 7, pp. 1693–1703, 2025. @article{Cazzoli2025,BACKGROUND: The true incidence of visuospatial neglect, impaired attention toward contralesional space, remains unclear. Common variability sources are sensitivity differences of conventional assessments and the exclusion of patients with language, motor, and other cognitive impairments. We aimed to determine the incidence of visuospatial neglect in an unselected cohort of patients with acute stroke using video oculography during free visual exploration, a newly established assessment overcoming the aforementioned biases. METHODS: Single-center, prospective, observational cohort study. We screened every patient admitted to a representative Swiss stroke center over 1 year (N=626). Two hundred eighty-five patients were eligible (first-ever stroke within 72 hours), and 221 were included. The incidence of visuospatial neglect was determined with conventional paper-pencil assessments and video oculography during free visual exploration. Demographic, risk, and stroke-related factors, as well as stroke localization, were also considered. Feasibility and ability to detect visuospatial neglect of the assessments were evaluated. RESULTS: The overall incidence of visuospatial neglect was ≈38%: widely varying location-specifically: ≈61% and ≈22% for stroke in the right and left cerebral hemispheres, respectively, and ≈14% to ≈37% for some less commonly affected infratentorial areas or multifocal stroke. In hemispheric stroke, visuospatial neglect was most common when the middle (≈64% right and ≈21% left) and posterior (≈53% right and ≈25% left) cerebral artery territories were affected. Neglect patients had higher National Institutes of Health Stroke Scale scores, more commonly atrial fibrillation and thrombectomy, and less commonly an undetermined stroke cause. They were older, with ≈4% yearly increase in the odds of having visuospatial neglect. Video oculography during free visual exploration was administrable and detected visuospatial neglect more often than conventional paper-pencil assessments. CONCLUSIONS: The incidence of visuospatial neglect in an unselected cohort, using a highly sensitive assessment, is considerably higher than previously assumed and can also occur after less typically localized strokes. These results can enhance the awareness of visuospatial neglect in the acute setting, potentially facilitating earlier identification and therapy of this disabling disorder. |
Shan-Mei Chang; Dai-Yi Wang; Zheng-Hong Guan Craving and attentional bias in gaming: Comparing esports, casual, and high-risk gamers using eye-tracking Journal Article In: Computers in Human Behavior, vol. 168, pp. 1–11, 2025. @article{Chang2025d,Attentional biases, as measured through eye movements, have been observed in both gaming disorders and substance addictions. However, few studies compare these biases among esports gamers (ESG), high-risk gamers (HRG), and other frequent gamers, despite ESG and HRG both groups dedicating significant time to gaming. This study included 47 male participants aged 15 to 19. Participants were categorized as ESG, casual gamers (CG), or HRG based on their MOBA experience, esports training, and Internet Gaming Disorder (IGD) scores. Each participant completed a dot-probe task with 56 stimulus conditions based on gaming cues, while eye-tracking technology recorded eye movements. The results indicated that HRG spent more total viewing time on stimulus images than ESG and CG. Additionally, HRG had longer first fixation durations and fewer saccade counts than the other two groups. Furthermore, HRG reported higher impulsivity and lower attentional focusing, suggesting a distinct psychological profile. Although ESG did not exhibit the same attentional biases as HRG, their self-reported gaming time was similar. This may be due to gaming being a career commitment for ESG, while for HRG, it serves as an escape from life pressures. Notably, eye-movement measures can identify high-risk tendencies early and uncover differences missed by self-report scales, including saccade count and attentional shifting. Caution is needed when diagnosing gaming disorder solely based on gaming time and self-reports. Future research could use attentional bias tasks as complementary diagnostic tools and further explore higher depression levels in HRG and ESG compared to CG. |
Xiaoxue Fu; Emma Platt; Frederick Shic; Jessica Bradshaw Infant social attention associated with elevated likelihood for autism spectrum disorder: A multi-method comparison Journal Article In: Journal of Autism and Developmental Disorders, vol. 55, no. 7, pp. 2337–2349, 2025. @article{Fu2025,Purpose: The study aimed to compare eye tracking (ET) and manual coding (MC) measures of attention to social and nonsocial information in infants with elevated familial likelihood (EL) of autism spectrum disorder (ASD) and low likelihood of ASD (LL). ET provides a temporally and spatially sensitive tool for measuring gaze allocation. Existing evidence suggests that ET is a promising tool for detecting distinct social attention patterns that may serve as a biomarker for ASD. However, ET is prone to data loss, especially in young EL infants. Methods: To increase evidence for ET as a viable tool for capturing atypical social attention in EL infants, the current prospective, longitudinal study obtained ET and MC measures of social and nonsocial attention in 25 EL and 47 LL infants at several time points between 3 and 24 months of age. Results: ET data was obtained with a satisfactory success rate of 95.83%, albeit with a higher degree of data loss compared to MC. Infant age and ASD likelihood status did not impact the extent of ET or MC data loss. There was a significant positive association between the ET and MC measures of attention, and separate analyses of attention using ET and AC measures yielded comparable findings. These analyses indicated group differences (EL vs. LL) in age-related change in attention to social vs. nonsocial information. Conclusion: Together, the findings support infant ET as a promising approach for identifying very early markers associated with ASD likelihood. |
Elisa Gavard; Valérie Chanoine; Franziska Geringswald; Jean-Luc Anton; Eddy Cavalli; Johannes C. Ziegler Neural networks for semantic and syntactic prediction and visual-motor statistical learning in adult readers with and without dyslexia Journal Article In: Neurobiology of Language, vol. 6, pp. 1–34, 2025. @article{Gavard2025,Prediction has become a key concept for understanding language comprehension, language production, and more recently reading. Recent studies suggest that predictive mechanisms in reading may be related to domain-general statistical learning (SL) abilities that support the extraction of regularities from sequential input. Both mechanisms have been discussed in relation to developmental dyslexia. Some suggest that SL is impaired in dyslexia with negative effects on the ability to make linguistic predictions. Others suggest that dyslexic readers rely to a greater extent on semantic and syntactic predictions to compensate for lower-level deficits. Here, we followed these two research questions in a single study. We therefore assessed the effects of semantic and syntactic prediction in reading and SL abilities in a population of university students with dyslexia and a group of typical readers using fMRI. The SL task was a serial reaction time (SRT) task that was performed inside and outside the scanner. The predictive reading task was performed in the scanner and used predictive versus nonpredictive semantic and syntactic contexts. Our results revealed distinct neural networks underlying semantic and syntactic predictions in reading, group differences in predictive processing in the left precentral gyrus and right anterior insula, and an association between predictive reading and SL, particularly in dyslexic readers. These findings contribute to our understanding of the interplay between SL, predictive processing, and compensation in dyslexia, providing new insights into the neural mechanisms that support reading. |
Marianna Kyriacou; Cecilie Rummelhoff; Franziska Köder Irony processing in adults with ADHD: Evidence from eye-tracking and executive attention tasks Journal Article In: Journal of Attention Disorders, vol. 29, no. 9, pp. 724–744, 2025. @article{Kyriacou2025a,Objective: ADHD is a neurodevelopmental disorder that impacts pragmatic communication abilities in children, including their understanding of verbal irony. This study aims to investigate whether adults with ADHD experience similar challenges in interpreting ironic statements, and to examine the role of executive attention abilities in accounting for any observed differences. Methods: 52 adults with ADHD and 55 neurotypical controls participated in an eye-tracking experiment. They read stories that included either literal or ironic statements and answered targeted comprehension questions. We used measures of working memory and fluid intelligence as independent indices of executive attention. Results: The results showed that adults with ADHD were as accurate as the control group in comprehending irony. However, they experienced an additional processing cost, indicated by increased reading times for ironic statements. While fluid intelligence improved comprehension accuracy in the control group, it did not have the same effect for participants with ADHD. Importantly, higher working memory capacity in adults with ADHD was associated with faster processing times, making their irony processing comparable to that of the control group. Conclusion: Our findings underscore the subtle challenges adults with ADHD face in processing irony and highlight the crucial role of working memory in enhancing performance. These insights stress the importance of considering individual cognitive capacities and their interaction with ADHD symptoms to better understand how ADHD impacts pragmatic abilities in adulthood. |
Aikaterini Premeti; Frédéric Isel; Maria Pia Bucci Eye movements of French dyslexic adults while reading texts: Evidence of word length, lexical frequency, consistency and grammatical category Journal Article In: Brain Sciences, vol. 15, no. 7, pp. 1–24, 2025. @article{Premeti2025,Background/Objectives: Dyslexia, a learning disability affecting reading, has been extensively studied using eye movements. This study aimed to examine in the same design the effects of different psycholinguistic variables, i.e., grammatical category, lexical frequency, word length and orthographic consistency on eye movement patterns during reading in adults. Methods: We compared the eye movements of forty university students, twenty with and twenty without dyslexia while they read aloud a meaningful and a meaningless text in order to examine whether semantic context could enhance their reading strategy. Results: Dyslexic participants made more reading errors and had longer reading time particularly with the meaningless text, suggesting an increased reliance on the semantic context to enhance their reading strategy. They also made more progressive and regressive fixations while reading the two texts. Similar results were found when examining grammatical categories. These findings suggest a reduced visuo-attentional span and reliance on a serial decoding approach during reading, likely based on grapheme-to-phoneme conversion. Furthermore, in the whole text analysis, there was no difference in fixation duration between the groups. However, when examining word length, only the control group exhibited a distinction between longer and shorter words. No significant group differences emerged for word frequency. Importantly, multiple regression analyses revealed that orthographic consistency predicted fixation durations only in the control group, suggesting that dyslexic readers were less sensitive to phonological regularities—possibly due to underlying phonological deficits. Conclusions: These findings suggest the involvement of both phonological and visuo-attentional deficits in dyslexia. Combined remediation strategies may enhance dyslexic individuals' performance in phonological and visuo-attentional tasks. |
Jing Zhu; Yuanlong Li; Changlin Yang; Hanshu Cai; Xiaowei Li; Bin Hu Transformer-based fusion model for mild depression recognition with EEG and pupil area signals Journal Article In: Medical and Biological Engineering and Computing, vol. 63, no. 7, pp. 2011–2027, 2025. @article{Zhu2025c,Early detection and treatment are crucial for the prevention and treatment of depression; compared with major depression, current researches pay less attention to mild depression. Meanwhile, analysis of multimodal biosignals such as EEG, eye movement data, and magnetic resonance imaging provides reliable technical means for the quantitative analysis of depression. However, how to effectively capture relevant and complementary information between multimodal data so as to achieve efficient and accurate depression recognition remains a challenge. This paper proposes a novel Transformer-based fusion model using EEG and pupil area signals for mild depression recognition. We first introduce CSP into the Transformer to construct single-modal models of EEG and pupil data and then utilize attention bottleneck to construct a mid-fusion model to facilitate information exchange between the two modalities; this strategy enables the model to learn the most relevant and complementary information for each modality and only share the necessary information, which improves the model accuracy while reducing the computational cost. Experimental results show that the accuracy of the EEG and pupil area signals of single-modal models we constructed is 89.75% and 84.17%, the precision is 92.04% and 95.21%, the recall is 89.5% and 71%, the specificity is 90% and 97.33%, the F1 score is 89.41% and 78.44%, respectively, and the accuracy of mid-fusion model can reach 93.25%. Our study demonstrates that the Transformer model can learn the long-term time-dependent relationship between EEG and pupil area signals, providing an idea for designing a reliable multimodal fusion model for mild depression recognition based on EEG and pupil area signals. |
Maggie E. Zink; Leslie Zhen; Jacie R. McHaney; Jennifer Klara; Kimberly Yurasits; Victoria E. Cancel; Olivia Flemm; Claire Mitchell; Jyotishka Datta; Bharath Chandresekaran; Aravindakshan Parthasarathy Increased listening effort and cochlear neural degeneration underlie speech-in-noise deficits in normal-hearing middle-aged adults Journal Article In: eLife, vol. 13, pp. 1–27, 2025. @article{Zink2025,Middle age represents a critical period of accelerated brain changes and provides a window for early detection and intervention in age-related neurological decline. Hearing loss is a key early marker of such decline and is linked to numerous comorbidities in older adults. Yet, ~10% of middle-aged individuals who report hearing difficulties show normal audiograms. Cochlear neural degeneration (CND) could contribute to these hidden hearing deficits, though its role remains unclear due to a lack of objective diagnostics and uncertainty regarding its perceptual outcomes. Here, we employed a cross-species design to examine neural and behavioral signatures of CND. We measured envelope following responses (EFRs) – neural ensemble responses to sound originating from the peripheral auditory pathway – in young and middle-aged adults with normal audiograms and compared these responses to young and middle-aged Mongolian gerbils, where CND was histologically confirmed. We observed near-identical changes in EFRs across species that were associated with CND. Behavioral assessments revealed age-related speech-in-noise deficits under challenging conditions, while pupil-indexed listening effort increased with age even when behavioral performance was matched. Together, these results demonstrate that CND contributes to speech perception difficulties and elevated listening effort in midlife, which may ultimately lead to listening fatigue and social withdrawal. |
Yuqing Cai; Christoph Strauch; Stefan Van der Stigchel; Antonia F. Ten Brink; Frans W. Cornelissen; Marnix Naber Mapping simulated visual field defects with movie-viewing pupil perimetry Journal Article In: Graefe's Archive for Clinical and Experimental Ophthalmology, vol. 263, no. 6, pp. 1641–1650, 2025. @article{Cai2025a,Purpose: Assessing the quality of the visual field is important for the diagnosis of ophthalmic and neurological diseases and, consequently, for rehabilitation. Visual field defects (VFDs) are typically assessed using standard automated perimetry (SAP). However, SAP requires participants to understand instructions, maintain fixation and sustained attention, and provide overt responses. These aspects make SAP less suitable for very young or cognitively impaired populations. Here we investigate the feasibility of a new and less demanding form of perimetry. This method assesses visual sensitivity based on pupil responses while performing the perhaps simplest task imaginable: watching movies. Method: We analyzed an existing dataset, with healthy participants (n = 70) freely watching movies with or without gaze-contingent simulated VFDs, either hemianopia (left- or right-sided) or glaucoma (large nasal arc, small nasal arc, and tunnel vision). Meanwhile, their gaze and pupil size were recorded. Using a recently published toolbox (Open-DPSM), we modeled the relative contribution of visual events to the pupil responses to indicate relative visual sensitivity across the visual field and to dissociate between conditions with and without simulated VFDs. Result: Conditions with and without simulated VFDs could be dissociated, with an AUC ranging from 0.85 to 0.97, depending on the specific simulated VFD condition. In addition, the dissociation was better when including more movies in the modeling but the model with as few movies as 10 movies was sufficient for a good classification (AUC ranging from 0.84 to 0.96). Conclusion: Movie-viewing pupil perimetry is promising in providing complementary information for the diagnosis of VFDs, especially for those who are unable to perform conventional perimetry. |
Eelke Vries; Freek Ede Microsaccades reveal preserved spatial organisation in visual working memory despite decay in location-based rehearsal Journal Article In: Cognition, vol. 259, pp. 1–13, 2025. @article{Vries2025,Space provides a foundational scaffold for retaining and selecting visual information in working memory. It remains unclear, however, whether and how spatial organisation in visual working memory persists over temporally extended memory delays, particularly when the locations of memoranda are incidental and never probed for report. Studies using continuous spatial markers of working-memory retention often report a gradual decay over time, which may or may not reflect a genuine decay in spatial organisation within working memory. To examine this, we capitalised on two recently established spatial eye-movement (microsaccade) markers of ‘location-based mnemonic rehearsal' and ‘location-based mnemonic selection' that we here studied during and following short (1 s), medium (3 s), and long (5 s) working-memory delays. Our findings, replicated across two experiments, demonstrate that while markers of location-based rehearsal may diminish throughout the working-memory delay, mnemonic selection remains anchored to incidentally encoded object locations. This implies that spatial organisation in working memory is preserved even when markers of active spatial rehearsal have meanwhile decayed, suggesting the notion of a “silent spatial scaffold” for working memory. |
Alessio Facchin; Jolanda Buonocore; Giulia Sgrò; Alessia Cristofaro; Marianna Crasà; Chiara Camastra; Maria Grazia Vaccaro; Aldo Quattrone; Andrea Quattrone Eye movement abnormalities in normal pressure hydrocephalus: A video-oculographic study Miscellaneous 2025. @misc{Facchin2025,Background: Eye movement dysfunction has been widely observed in several neurodegenerative diseases. Normal pressure hydrocephalus (NPH) is a treatable condition showing marked clinical and radiological overlap with neurodegenerative parkinsonism and dementia syndromes, often posing diagnostic challenges. The current study employed video-oculography (VOG) aiming to comprehensively explore possible ocular dysfunction in NPH patients. Methods: Forty-two consecutive NPH patients and seventy-six healthy controls (HC) were enrolled in the study. Participants underwent a video-oculographic assessment including reflexive saccades and fixation tasks. Amplitude, peak velocity and latency of upward, downward, and vertical saccades were calculated, together with square wave jerks (SWJ) number and amplitude during fixation. Correlations between VOG data and clinico-radiological features were investigated. Results: NPH patients showed a significant (33.8%) increase in saccadic latency compared to HC, with no differences in saccadic amplitude and peak velocity. The number and amplitude of SWJ were also similar between NPH and HC groups. Saccadic latency was specifically associated with cognitive deficits, especially phonemic fluency and executive functions, in the NPH group. Conclusion: This study characterized ocular dysfunction in NPH patients, demonstrating an increase of saccadic latency in comparison with HC, strongly associated with cognitive impairment. These results identified saccadic latency as a rapid and quantitative VOG biomarker of cognitive deficits in NPH, holding potential for repeated assessment of cognitive status over time. On the other hand, saccadic amplitude and velocity were not affected in NPH, thus suggesting their possible role in the differential diagnosis between NPH and neurodegenerative parkinsonian syndromes. |
Lee Friedman; Oleg V. Komogortsev Fixation drift increases as a function of time-on-task in a brief saccade tracking study Journal Article In: PLoS One, vol. 20, pp. 1–17, 2025. @article{Friedman2025,Ocular fixations contain microsaccades, drift and tremor. We report an increase in the slope of linear fixation drift as a function of time-on-task (TOT). We employed a large dataset (322 subjects, multiple visits per subject). Subjects performed a random saccade task. The task, in which the target dot jumped randomly every one sec, was 100 sec in duration. For each fixation, we regressed eye position against time across multiple segment lengths (50, 100, 300, and 500 ms). We started with the first sample and continued until no further regressions were possible based on the segment length being evaluated. For each segment length, each fixation was characterized by a single value: the maximum slope over the segment length. The slopes were expressed in deg/sec. We were not interested in the direction of the linear drift, so we took the absolute value of the slope as a measure. For data analysis, each 100 sec task was divided into five 20 sec epochs. In an attempt to partially replicate an earlier study of fixation drift over time [1], we also measured drift as the mean velocity of an eye-position signal that had been low-pass filtered at 30 Hz. We found that both methods detected significant drift over our task. For each visit, subjects were tested in two sessions, approximately 20 min apart. Generally, we found statistically significant session effects indicating that drift started at a higher level and increased at a higher rate over the second session. We report that the mean velocity method detects distinctive types of drifting fixation trajectories including curvilinear drift and irregular oscillation. Our findings extend the observations of increased drift over time by [1] to other measures of drift and to a much shorter time interval (100 sec vs two hrs) and a simpler task. |
Angelina Ganebnaya; Aiga Svede; Alina Kucika; Jekaterina Berkova; Alona Purmale; Liga Puhova; Mariya Misri; Svetlana Semjonova; Davids Davis Gailitis; Atis Kovalovs Application of a new device for saccadic training in athletes Journal Article In: Life, vol. 15, no. 6, pp. 1–21, 2025. @article{Ganebnaya2025,The aim of our study was to test the application of a new vision training device, the EYE ROLL, for home-based eye movement training in athletes. Sixty-seven participants were randomly divided into three groups: a control group (no training); an eye movement training group with no device; and a group using the new EYE ROLL device. The results of 51 participants were used for statistical analyses after a 4-week period. Before and after the 4-week period, participants underwent the same assessment procedures: a comprehensive vision examination and saccadic eye movement recording. Before training, for both 10° and 5° stimuli, all subjects showed statistically significantly larger and faster rightward saccades compared to leftward saccades. After four weeks, the control group showed increased horizontal saccadic asymmetry and a decrease in leftward saccade amplitude. However, both velocities showed asymmetry in both visits. There were larger changes in saccadic parameters for leftward saccades, but no clear changes in saccadic response asymmetry after training. There were no consistent differences between the training groups. The EYE ROLL is a novel device that may serve as a substitute training tool for saccadic enhancement and may improve the symmetry of horizontal saccadic movements after four weeks of home-based training. |
Timothy L. Hodgson; Phoebe Cartwright; Joseph Dodd; Annabelle Hippisley Oculomotor deficits in children with sensory processing difficulties Journal Article In: British Journal of Occupational Therapy, vol. 88, no. 6, pp. 352–361, 2025. @article{Hodgson2025,Background: Atypically developing children often present with a variety of sensory processing difficulties which have been proposed to reflect abnormal development of pathways integrating sensation and action. A brain system in which the process of sensorimotor integration is particularly well understood is the oculomotor system, but no studies to date have used computerised eye tracking to assess eye movements in children with sensory processing difficulties. Method: Ten children with sensory processing difficulties completed a battery of oculomotor tasks comprising pro-saccades, anti-saccades, smooth pursuit tracking and sustained fixation. Eye movements were recorded using a high-resolution eye tracker. Results: Compared to age-matched controls, children with sensory processing difficulties were found to make more directional errors in the anti-saccade task and less-accurate smooth pursuit and sustained fixation. Conclusion: Consistent differences were found in oculomotor ability in children with sensory processing difficulties which are likely to impact children's ability to process and respond to visual information within home and school contexts. Further research is needed to understand the relationship between oculomotor deficits in children with sensory processing difficulties and the presence/absence of neurodevelopmental diagnoses. Eye tracking may be of value in the future for assessment and objective evaluation of interventions for sensory processing difficulties such as sensory integration therapy. |
Ruben Jauregui; Andrew M. Evens; Anastasia Zekeridou; Claude Steriade; Todd Hudson; Gerald T. Voelbel; Steven L. Galetta; Janet C. Rucker Anti-RGS8 paraneoplastic neurologic syndrome presenting with skew deviation and mild cerebellar dysfunction Journal Article In: Cerebellum, vol. 24, no. 3, pp. 1–6, 2025. @article{Jauregui2025,RGS8-associated paraneoplastic neurologic syndrome (PNS) is a recently-described disorder associated with lymphomas and typically presenting with severe, rapidly-progressing cerebellar dysfunction. We describe a patient who presented with mild signs of cerebellar dysfunction, including ocular motor abnormalities and impaired tandem gait. CSF showed elevated protein and a neural-restricted antibody pattern. Mesenteric lymphadenopathy on abdominal CT was biopsied and diagnosed as follicular B-cell lymphoma. After four years, the previously-detected antibody pattern was identified as RGS8 antibodies. This case describes the first RGS8-PNS patient presenting with a subtle and ocular motor predominant cerebellar syndrome with low-grade lymphoma. |
Arianna N. LaCroix; Ileana Ratiu Saccades and blinks index cognitive demand during auditory noncanonical sentence comprehension Journal Article In: Journal of Cognitive Neuroscience, vol. 37, no. 6, pp. 1147–1172, 2025. @article{LaCroix2025,Noncanonical sentence structures pose comprehension challenges because they require increased cognitive demand. Prosody may partially alleviate this cognitive load. These findings largely stem from behavioral studies, yet physiological measures may reveal additional insights into how cognition is deployed to parse sentences. Pupillometry has been at the forefront of investigations into physiological measures of cognitive demand during auditory sentence comprehension. This study offers an alternative approach by examining whether eye-tracking measures, including blinks and saccades, index cognitive demand during auditory noncanonical sentence comprehension and whether these metrics are sensitive to reductions in cognitive load associated with typical prosodic cues. We further investigated how eye-tracking patterns differ across correct and incorrect responses, as a function of time, and how each related to behavioral measures of cognition. Canonical and noncanonical sentence comprehension was measured in 30 younger adults using an auditory sentence-picture matching task. We also assessed participants' attention and working memory. Blinking and saccades both differentiate noncanonical sentences from canonical sentences. Saccades further distinguish noncanonical structures from each other. Participants made more saccades on incorrect than correct trials. The number of saccades also related to working memory, regardless of syntax. However, neither eye-tracking metric was sensitive to the changes in cognitive demand that was behaviorally observed in response to typical prosodic cues. Overall, these findings suggest that eye-tracking indices, particularly saccades, reflect cognitive demand during auditory noncanonical sentence comprehension when visual information is present, offering greater insights into the strategies and neural resources participants use to parse auditory sentences. |
Xiaobo Liu; Yuxi Li; Yuan Chen; Chen Xue; Jin Fan; Jiaming Zhang; Dongling Zhong; Qinjian Dong; Zhong Zheng; Juan Li; Rongjiang Jin Attentional bias toward threatening stimuli in major depressive disorder: A free-viewing eye-tracking study Journal Article In: Journal of Affective Disorders, vol. 378, pp. 352–359, 2025. @article{Liu2025q,Object: Limited evidence exists regarding negative attentional bias toward threatening stimuli in patients with major depressive disorder (MDD). This cross-sectional study aimed to explore attentional bias toward threatening stimuli in patients with MDD. Method: Hamilton Depression Scale-24 items (HAMD-24) and Hamilton Anxiety Scale (HAMA) were used to assess all participants. The MDD and healthy participants freely viewed images with positive, threatening, and neutral valence for 1000 ms, during which eye movements were recorded with the Eyelink system. Eye-tracking metrics including the mean fixation duration, mean fixation counts, mean saccade counts, mean saccade velocity, mean saccade amplitude, and mean pupil diameter were compared between MDD and healthy groups. Correlations between eye-tracking variables and both HAMD-24 total scores and factor scores were analyzed. Results: The study included 100 MDD participants and 100 matched healthy controls. The MDD patients had longer mean fixation duration and reduced saccade counts on threatening and neutral images compared to the healthy controls. Additionally, the MDD patients showed prolonged mean fixation duration and reduced mean fixation counts and saccade counts when viewing threatening images compared to positive images. In contrast, no bias was observed in the healthy controls. Regarding mean pupil diameter, MDD participants showed greater mean pupil diameter for threatening images compared to neutral and positive images. No significant differences were observed in mean saccade velocity and saccade amplitude between the groups. There were positive correlations between mean fixation duration on threatening stimuli and retardation factor scores of HAMD-24. Conclusion: Patients with MDD exhibit abnormal attentional bias toward threatening stimuli, which is associated with the severity of retardation symptoms in MDD. |
Jana Masselink; Markus Lappe Adaptation across the 2D population code explains the spatially distributive nature of motor learning Journal Article In: PLoS Computational Biology, vol. 21, pp. 1–31, 2025. @article{Masselink2025,In current computational models on oculomotor learning ‘the' movement vector is adapted in response to targeting errors. However, for saccadic eye movements, learning exhibits a spatially distributive nature, i.e. it transfers to surrounding positions. This adaptation field resembles the topographic maps of visual and motor activity in the brain and suggests that learning does not act on the population vector but already on the level of the 2D population response. Here we present a population-based gain field model for saccade adaptation in which sensorimotor transformations are implemented as error-sensitive gain field maps that modulate the population response of visual and motor signals and of the internal saccade estimate based on corollary discharge (CD). We fit the model to saccades and visual target localizations across adaptation, showing that adaptation and its spatial transfer can be explained by locally distributive learning that operates on visual, motor and CD gain field maps. We show that 1) the scaled locality of the adaptation field is explained by population coding, 2) its radial shape is explained by error encoding in polar-angle coordinates, and 3) its asymmetry is explained by an asymmetric shape of learning rates along the amplitude dimension. Learning exhibits the highest peak rate, the widest spatial extension and a pronounced asymmetry in the motor domain, while in the visual and the internal saccade domain learning appears more localized. Moreover, our results suggest that the CD-based internal saccade representation has a response field that monitors only part of the ongoing saccade changes during learning. Our framework opens the door to study spatial generalization and interference of learning in multiple contexts. |
Rozana Ovsepian; David Souto; Alexander C. Schütz Robust generalization of tuning to self-induced sensation Journal Article In: iScience, vol. 28, no. 6, pp. 1–12, 2025. @article{Ovsepian2025,Perceptual and sensorimotor learning is often specific to the trained stimuli and movement parameters. This specificity also applies to recalibrating sensory and motor maps, such as saccadic eye movements in response to systematic visual errors. Here, we show that the perceptual recalibration of stationarity during smooth pursuit eye movements generalizes to untrained eye movement speeds. During smooth pursuit, the retinal image motion of the stationary surround (reafference) must be compensated to maintain perceptual stability. Prior research revealed that the predicted reafference signal is continuously updated through interactions between the motor command and experienced retinal motion and is specific to movement direction and visual field location. Here, we show that stationarity recalibration transfers across pursuit speeds. The generalization pattern reveals two distinct mechanisms: a multiplicative gain for decreasing predicted reafference signals and a constant shift for increasing signals. The former is consistent with a gain control model of smooth pursuit. |
Lisa Schwetlick; Sebastian Reich; Ralf Engbert Bayesian dynamical modeling of fixational eye movements Journal Article In: Biological Cybernetics, vol. 119, no. 2, pp. 1–18, 2025. @article{Schwetlick2025a,Humans constantly move their eyes, even during visual fixations, where miniature (or fixational) eye movements occur involuntarily. Fixational eye movements comprise slow components (physiological drift and tremor) and fast components (microsaccades). The complex dynamics of physiological drift can be modeled qualitatively as a statistically self-avoiding random walk (SAW model, Engbert et al., 2011). In this study, we implement a data assimilation approach for the SAW model to explain statistics of fixational eye movements and microsaccades in experimental data obtained from high-resolution eye-tracking. We discuss and analyze the likelihood function for the SAW model, which allows us to apply Bayesian parameter estimation at the level of individual human observers. Based on model fitting, we find a relationship between the activation predicted by the SAW model and the occurrence of microsaccades. The model's latent activation relative to microsaccade onsets and offsets using experimental data lends support to the existence of a triggering mechanism for microsaccades. Our findings suggest that the SAW model can capture individual differences and serve as a tool for exploring the relationship between physiological drift and microsaccades as the two most essential components of fixational eye movements. Our results contribute to understanding individual variability in microsaccade behaviors and the role of fixational eye movements in visual information processing. |
Nancy Sotero Silva; Christoph Kayser; Felix Bröhl In: Hearing Research, vol. 461, pp. 1–11, 2025. @article{SoteroSilva2025,Eye movement-related eardrum oscillations (EMREOs) reflect movements of the tympanic membrane that scale with the magnitude and direction of saccades. EMREOs have been consistently described in humans and non-human primates, yet many questions regarding this phenomenon remain unresolved. Based on bilateral in-ear recordings in human participants we here explore several properties of these EMREOs in order to improve our understanding of this signal's origin and functional significance. Our data support that the EMREO time course is comparable between the left and right ears, and between paradigms guiding saccades by visual and auditory target stimuli. However, the precise amplitude time course differs significantly between ipsi- and contralateral saccades in addition to the previously known phase-inversion described for saccades in opposing directions. Finally, our data suggest that the EMREO amplitude is negatively related to the compliance of the tympanic membrane as established by tympanometry. Collectively, these results support the notion that EMREOs reflect motor-related top-down signals relayed to the ear from yet-to-be-resolved sources, and fuel the speculation that EMREOs may be generated by the middle ear muscles in a differential operation similar to the execution of ipsi- and contralateral saccades. |
Yiyang Yang; Hulin Ren Attention and outcomes across learning conditions in lL2 vocabulary acquisition: Evidence from eye-tracking Journal Article In: Journal of Eye Movement Research, vol. 18, no. 3, pp. 1–21, 2025. @article{Yang2025c,The role of attention has been shown to be essential in second language (L2) learning. However, the impact of different learning conditions on attention and learning outcomes remains underdeveloped, particularly through the application of eye-tracking technology. This study aims to evaluate the effect of intentional learning conditions (i.e., data-driven learning) on vocabulary learning and attentional allocations. Twenty-six intermediate English L2 learners participated in the study to learn the usage of four artificial attributive adjectives in noun phrases (NPs). Learning outcomes were analysed to assess the types of knowledge developed, shedding light on the role of attention and the conscious processing of word usage. Eye-tracking data, collected using Eyelink 1000 plus, investigated gaze patterns and the allocation of attentional sources when applying the learned usage of adjectives. The results indicate that fixation stability and regression movements significantly differ under the impact of intentional learning conditions. Post-test results also indicate a shift in attention from the target adjectives to the associated nouns. These findings underscore the critical role of attention and highlight the influence of learning conditions on L2 vocabulary learning, providing practical implications and empirical validation for L2 educators and researchers aiming to enhance vocabulary instruction through intentional learning strategies. |
Stéphanie Ducrot; Bernard Lété; Marie Vernet; Delphine Massendari; Jérémy Danna Improving reading and eye movement control in readers with oculomotor and visuo-attentional deficits Journal Article In: Journal of Eye Movement Research, vol. 18, no. 4, pp. 1–20, 2025. @article{Ducrot2025,The initial saccade of experienced readers tends to land halfway between the beginning and the middle of words, at a position originally referred to as the preferred viewing location (PVL). This study investigated whether a simple physical manipulation—namely, increasing the saliency (brightness or color) of the letter located at the PVL—can positively influence saccadic targeting strategies and optimize reading performance. An eye-movement experiment was conducted with 25 adults and 24 s graders performing a lexical decision task. Results showed that this manipulation had no effect on initial landing positions in proficient readers, who already landed most frequently at the PVL, suggesting that PVL saliency is irrelevant once automatized saccade targeting routines are established. In contrast, the manipulation shifted the peak of the landing site distribution toward the PVL for a cluster of readers with immature saccadic strategies (with low reading-level scores and ILPs close to the beginning of words), but only in the brightness condition, and had a more compelling effect in a cluster with oculomotor instability (with flattened and diffuse landing position curves along with oculomotor and visuo-attentional deficits). These findings suggest that guiding the eyes toward the PVL may offer a novel way to improve reading efficiency, particularly for individuals with oculomotor and visuo-attentional difficulties. |
Haneieh Molaei; Reza Abbas Farishta; Reza Farivar Multi-feature mapping of distortions in amblyopia with localized sampling Journal Article In: Investigative Ophthalmology and Visual Science, vol. 66, no. 6, pp. 1–15, 2025. @article{Molaei2025a,PURPOSE. The purpose of this study was to investigate position, orientation, and spatial frequency (SF) distortions in amblyopia, their distribution across the visual field (VF), and their relationship with visual acuity (VA) loss. METHODS. Twenty-one participants with amblyopia were tested using three tasks measuring distortions in position, orientation, and SF. Stimuli were presented on a 6 × 6 grid covering the central 5 degrees of the VF, with participants adjusting the fellow eye's perception to match the amblyopic eye. Distortion maps were created for each type, and correlations were analyzed within subjects (across their 3 distortion maps) and between subjects (comparing the same type of distortion maps across participants). Correlations with VA loss were also assessed. RESULTS. The prevalence of distortion maps varied, with SF distortions being the most dominant (88.9%), followed by position distortions (66.7%), and orientation distortions being the least common (22.2%). Distortions extended beyond the fovea. Within subjects, spatial patterns of distortion showed no significant correlations across distortion types (P > 0.05), indicating their independence. Between subjects, no significant correlations were found for the same type of distortion map, suggesting individual variability. Additionally, VA differences were not significantly correlated with any distortion type, reinforcing the independence of VA from perceptual distortions. CONCLUSIONS. This study highlights the importance of assessing multiple distortion types to fully characterize perceptual deficits in amblyopia. The findings suggest that no single distortion type fully represents amblyopic spatial distortion, as each operates independently. Distortion mapping is essential for understanding, monitoring improvements, and accurately diagnosing amblyopia, as VA measurements alone fail to address these deficits comprehensively. |
Daniel J. Pearce; Gerard M. Loughnane; Trevor T. J. Chong; Nele Demeyere; Jason B. Mattingley; Margaret J. Moore; Peter W. New; Redmond G. O'Connell; Megan H. O'Neill; Dragan Rangelov; Renerus J. Stolwyk; Sam S. Webb; Shou Han Zhou; Méadhbh B. Brosnan; Mark A. Bellgrove Target selection signals causally influence human perceptual decision-making Journal Article In: The Journal of Neuroscience, vol. 45, no. 24, pp. 1–13, 2025. @article{Pearce2025,The ability to form decisions is a foundational cognitive function which is impaired across many psychiatric and neurological conditions. Understanding the neural processes underpinning clinical deficits may provide insights into the fundamental mechanisms of decision-making. The N2c has been identified as an EEG signal indexing the efficiency of early target selection, which subsequently influences the timing of perceptual reports through modulating neural evidence accumulation rates. Evidence for the contribution of the N2c to human decision-making however has thus far come from correlational research in neurologically healthy individuals. Here, we capitalized on the superior temporal resolution of EEG to show that unilateral brain lesions in male and female humans were associated with specific deficits in both the timing and strength of the N2c in the damaged hemisphere, with corresponding deficits in the timing of perceptual reports contralaterally. The extent to which the N2c influenced clinical deficits in perceptual reporting speed depended on neural rates of evidence accumulation. This work provides causal evidence that the N2c indexes an early, hemisphere-specific process supporting human decision-making. This noninvasive EEG marker could be used to monitor novel approaches for remediating clinical deficits in perceptual decision-making across a range of brain disorders. |
Mario Reutter; Janna Teigeler; Matthias Gamer The influence of (social) anxiety and visual exploration on threat responding and generalization Journal Article In: Behaviour Research and Therapy, vol. 189, pp. 1–12, 2025. @article{Reutter2025,Fear generalization has been identified as an important mechanism that might contribute to the etiology and maintenance of anxiety disorders. It is, however, yet unclear to what degree attentional processes contribute to overgeneralization of fear in clinical samples. To address this issue, we utilized a set of facial photographs that was meticulously created such that pairs of faces could either be distinguished by looking into the eyes or the region around mouth and nose, respectively. These pairs were then employed as CS+ and CS− in a differential fear conditioning paradigm followed by a generalization test with morphs in steps of 20 %, creating a continuum between CS+ and CS−. In a sample with diverse levels of social and general anxiety (N = 87), we demonstrated that the amount of fear generalization depends on attentional orienting towards diagnostic facial features. While social anxiety did not affect the shape of generalization gradients, we observed altered visual exploration patterns and a distinct multi-phasic heart rate modulation in participants with higher social anxiety. General anxiety symptomatology was also related to these characteristics of visual exploration and additionally predicted a broad elevation of threat ratings. In summary, fear generalization depends on attentional deployment. Future work should build on these findings to further explore these processes in clinical populations. |
Melinda Y. Chang; Mark S. Borchert Cerebral/cortical visual impairment classification and categorization using eye tracking measures of oculomotor function Journal Article In: Ophthalmology Science, vol. 5, no. 3, pp. 1–11, 2025. @article{Chang2025a,Purpose: Cerebral/cortical visual impairment (CVI) is a leading cause of pediatric visual impairment and is frequently associated with abnormal ocular motility. Eye tracking has previously been used to characterize oculomotor function in CVI. The purpose of this study was to evaluate the utility of eye tracking in diagnosis, categorization, and prognostication of CVI. Design: Prospective longitudinal study. Participants: Thirty-nine children with CVI and 41 age-matched controls. Methods: Children with CVI underwent 4 eye tracking sessions over 1 year, and age-matched controls completed 1 eye tracking session. Fixations and saccades were labeled by the eye tracking software and used to compute 9 oculomotor features. In children with CVI, unsupervised data-driven clustering analysis using these 9 features was performed to identify 3 CVI eye tracking oculomotor groups. Clinical and demographic characteristics of eye tracking oculomotor groups were compared. Main Outcome Measures: (1) Area under the curve (AUC) for eye tracking oculomotor features in classifying patients with CVI and controls; (2) differences between 3 CVI eye tracking oculomotor groups on clinical and demographic characteristics; and (3) change in visual acuity (VA) over 1 year in 3 CVI eye tracking oculomotor groups. Results: Six oculomotor features (fixation and saccade latency, frequency, and off-screen proportion) had an AUC ≥0.90 in classifying children with CVI and controls (P < 0.0001). Cerebral/cortical visual impairment eye tracking oculomotor groups had significantly different VA (P < 0.0001) and change in VA over 1 year (P = 0.049). Patients in group B, who had the greatest improvement in VA, were younger and had higher rates of term hypoxic ischemic encephalopathy. Conclusions: Eye tracking measures of oculomotor function accurately distinguish between children with CVI and age-matched controls. Clustering analysis revealed 3 CVI eye tracking oculomotor groups with prognostic significance. Eye tracking shows promise as an objective, quantitative measure of oculomotor function in CVI that may in future be useful in both clinical practice (for longitudinal assessment, prognostication, and guiding individualized interventions) and research (as an outcome measure or method to stratify patients in clinical trials). Financial Disclosure(s): Proprietary or commercial disclosure may be found in the Footnotes and Disclosures at the end of this article. |
Geoffrey Kaye; Edan Johnston; Jaiden Burke; Natalie Gasson; Welber Marinovic Differential effects of visual and auditory cognitive tasks on smooth pursuit eye movements Journal Article In: Psychophysiology, vol. 62, no. 5, pp. 1–10, 2025. @article{Kaye2025,Smooth pursuit eye movements (SPEM) are important to gather visual information that guides our interactions with moving objects (e.g., tracking a tennis ball, or following a car when driving). In many neurological conditions, from Parkinson's disease to stroke, the voluntary control of SPEM can be compromised. Therefore, SPEMs can serve as sensitive proxies for assessing cognitive and sensorimotor function. Prior research has shown that SPEMs are influenced by attention and working memory load, yet it remains unclear how the sensory modality of concurrent tasks interacts with these effects. Here, we conducted a 3 (working memory load: no load, easy [low load], and hard [high load]) × 2 (sensory modality: visual vs. auditory) experiment to examine how working memory load and secondary task modality interact to affect SPEM in healthy young adults. Participants tracked a moving circle while simultaneously performing an arithmetic task, where they added either constant (1) or variable (1–5) numbers which were presented visually or auditorily. Our results showed that a secondary auditory task increased tracking variability during high cognitive load. In contrast, we found that the visual task improved tracking, reducing variability irrespective of cognitive load. We interpret our results as evidence that auditory processing requires additional top-down control that is critical for the control of smooth pursuit, diverting resources required for smooth pursuit and, consequently, increasing SPEM variability. These findings emphasize the importance of sensory modality in understanding the interactions between working memory and oculomotor control. We suggest that auditory secondary cognitive tasks may provide a more sensitive test of sensorimotor control deficits in future research with clinical populations. |
Qunyue Liu; Xiabin Lin; Qin Wang; Yuxiang Lan; Zhipeng Zhu; Xiong Yao; Yaling Gao; Yuanping Shen; Meng Huang; Hongxin Wang How do nature type and expertise impact restorative perceptions and eye movements? A between-subjects eye-tracking study Journal Article In: People and Nature, vol. 7, no. 5, pp. 1198–1210, 2025. @article{Liu2025l,Previous research has shown that natural environments and landscape-related expertise affect psychological restoration and visual behaviour. However, little is known about how subtle differences in naturalness across similar settings, and the role of expertise, influence restorative benefits and eye movements. This study addresses these gaps by investigating how different nature settings—wild nature, tended nature (includes plaza, lawn, path, pool and waterfall settings), and urban environments—influence human preferences, restorative perceptions and eye movements. A between-subjects experimental design was used, with 280 participants randomly assigned to one of seven landscape settings (40 participants per setting). Eye movements were tracked during the experiment to assess visual engagement. The study found that the type of setting significantly influenced preferences, restorative potential and outcomes. Wild nature, along with two tended nature settings (pool and waterfall), was rated higher in restorative potential compared with urban and plaza settings by both expert and non-expert groups. No significant differences were observed between pool, waterfall and wild nature settings in these ratings. While expertise influenced preferences in lawn, path and waterfall settings, it did not significantly impact perceptions of restorative potential or outcomes in most settings. Furthermore, settings had a stronger effect on eye movements in non-experts, with notable differences in eye movement behaviour between the two groups. This study emphasizes the importance of designing landscapes that cater to the diverse needs and preferences of different user groups. The findings contribute to the interdisciplinary field of people–nature relationships, providing insights for landscape architecture, urban planning and public health. |
Yahdi Siradj; Kiki Maulana Adhinugraha; Eric Pardede Towards structured gaze data classification: The gaze data clustering taxonomy (GCT) Journal Article In: Multimodal Technologies and Interaction, vol. 9, no. 5, pp. 1–25, 2025. @article{Siradj2025,Gaze data analysis plays a crucial role in understanding human visual attention and behaviour. However, raw gaze data is often noisy and lacks inherent structure, making interpretation challenging. Therefore, preprocessing techniques such as classification are essential to extract meaningful patterns and improve the reliability of gaze-based analysis. This study introduces the Gaze Data Clustering Taxonomy (GCT), a novel approach that categorises gaze data into structured clusters to improve its reliability and interpretability. GCT classifies gaze data based on cluster count, target presence, and spatial–temporal relationships, allowing for more precise gaze-to-target association. We utilise several machine learning techniques, such as k-NN, k-Means, and DBScan, to apply the taxonomy to a Random Saccade Task dataset, demonstrating its effectiveness in gaze classification. Our findings highlight how clustering provides a structured approach to gaze data preprocessing by distinguishing meaningful patterns from unreliable data. |
Ankan Biswas; Wupadrasta Santosh Kumar; Kanishka Sharma; Supratim Ray Stimulus-induced gamma sources reduce in power but not in spatial extent with healthy aging in human EEG Journal Article In: European Journal of Neuroscience, vol. 61, no. 10, pp. 1–12, 2025. @article{Biswas2025,Aging alters brain structure and function, and studying such changes may help understand the neural basis underlying aging and devise interventions to detect deviations from healthy progression. Electroencephalogram (EEG) offers an effective way to study healthy aging owing to its high temporal resolution and affordability. Recent studies have shown that narrow-band stimulus-induced gamma oscillations (20–70 Hz) in EEG, induced with Cartesian gratings in a fixation task paradigm, weaken with healthy aging and onset of Alzheimer's disease (AD) while remaining highly reproducible for a given subject and thus hold promise as potential biomarkers. However, functional connectivity (FC) sometimes changes in a different way compared with sensor power with aging. This difference could be potentially addressed by studying how underlying gamma sources change with aging, since either a reduction in source power or a shrinkage of the sources (or both) could reduce the power in the sensors but may have different effects on other measures such as FC. We therefore reconstructed EEG gamma sources through a linear inverse method called exact low-resolution tomography analysis (eLORETA) on a large (N = 217) cohort of healthy elderly subjects (> 50 years). We further characterized gamma distribution in cortical space as an exponential fall-off from a seed voxel with maximal gamma source power to delineate a reduction in magnitude versus shrinkage. We found a significant reduction in magnitude but not shrinkage with healthy aging. Overall, our results shed light on changes in EEG gamma source distribution with healthy aging, which could provide clues about underlying neural mechanisms. |
Caitlin M. Hudac; Kelsey Dommer; Monique Mahony; Trent D. DesChamps; Brianna Cairney; Rachel Earl; Evangeline C. Kurtz-Nelson; Jessica Bradshaw; Raphael A. Bernier; Evan E. Eichler; Emily Neuhaus; Sara Jane Webb; Frederick Shic Visual and auditory attention in individuals with DYRK1A and SCN2A disruptive variants Journal Article In: Autism Research, vol. 18, no. 5, pp. 909–921, 2025. @article{Hudac2025,This preliminary study sought to assess biomarkers of attention using electroencephalography (EEG) and eye tracking in two ultra-rare monogenic populations associated with autism spectrum disorder (ASD). Relative to idiopathic ASD (n = 12) and neurotypical comparison (n = 49) groups, divergent attention profiles were observed for the monogenic groups, such that individuals with DYRK1A (n = 9) exhibited diminished auditory attention condition differences during an oddball EEG paradigm whereas individuals with SCN2A (n = 5) exhibited diminished visual attention condition differences noted by eye gaze tracking when viewing social interactions. Findings provide initial support for alignment of auditory and visual attention markers in idiopathic ASD and neurotypical development but not monogenic groups. These results support ongoing efforts to develop translational ASD biomarkers within the attention domain. |
Lukas Suveg; Tanvi Thakkar; Emily Burg; Shelly P. Godar; Daniel Lee; Ruth Y. Litovsky The relationship between spatial release from masking and listening effort among cochlear implant users with single-sided deafness Journal Article In: Ear and Hearing, vol. 46, no. 3, pp. 624–639, 2025. @article{Suveg2025,Objectives: To examine speech intelligibility and listening effort in a group of patients with single-sided deafness (SSD) who received a cochlear implant (CI). There is limited knowledge on how effectively SSD-CI users can integrate electric and acoustic inputs to obtain spatial hearing benefits that are important for navigating everyday noisy environments. The present study examined speech intelligibility in quiet and noise simultaneously with measuring listening effort using pupillometry in individuals with SSD before, and 1 year after, CI activation. The study was designed to examine whether spatial separation between target and interfering speech leads to improved speech understanding (spatial release from masking [SRM]), and is associated with a decreased effort (spatial release from listening effort [SRE]) measured with pupil dilation (PPD). Design: Eight listeners with adult-onset SSD participated in two visits: (1) pre-CI and (2) post-CI (1 year after activation). Target speech consisted of Electrical and Electronics Engineers sentences and masker speech consisted of AzBio sentences. Outcomes were measured in three target-masker configurations with the target fixed at 0° azimuth: (1) quiet, (2) co-located target/maskers, and (3) spatially separated (±90° azimuth) target/maskers. Listening effort was quantified as change in peak proportional PPD on the task relative to baseline dilation. Participants were tested in three listening modes: acoustic-only, CI-only, and SSD-CI (both ears). At visit 1, the acoustic-only mode was tested in all three target-masker configurations. At visit 2, the acoustic-only and CI-only modes were tested in quiet, and the SSD-CI listening mode was tested in all three target-masker configurations. Results: Speech intelligibility scores in quiet were at the ceiling for the acoustic-only mode at both visits, and in the SSD-CI listening mode at visit 2. In quiet, at visit 2, speech intelligibility scores were significantly worse in the CI-only listening modes than in all other listening modes. Comparing SSD-CI listening at visit 2 with pre-CI acoustic-only listening at visit 1, speech intelligibility scores for co-located and spatially separated configurations showed a trend toward improvement (higher scores) that was not significant. However, speech intelligibility was significantly higher in the separated compared with the co-located configuration in acoustic-only and SSD-CI listening modes, indicating SRM. PPD evoked by speech presented in quiet was significantly higher with CI-only listening at visit 2 compared with acoustic-only listening at visit 1. However, there were no significant differences between co-located and spatially separated configurations on PPD, likely due to the variability among this small group of participants. There was a negative correlation between SRM and SRE, indicating that improved speech intelligibility with spatial separation of target and masker is associated with a greater decrease in listening effort on those conditions. Conclusions: The small group of patients with SSD-CI in the present study demonstrated improved speech intelligibility from spatial separation of target and masking speech, but PPD measures did not reveal the effects of spatial separation on listening effort. However, there was an association between the improvement in speech intelligibility (SRM) and the reduction in listening effort (SRE) from spatial separation of target and masking speech. |
Jialu You; Xi Liu; Jing Yang; Liyuan Zhang; Le Zhang; Quan Wang Quantifying the impact of mild and moderate myopia on attention in school-age children through eye tracking Journal Article In: European Journal of Pediatrics, vol. 184, no. 5, 2025. @article{You2025,Objectives: By utilizing eye-tracking data, this study aims to evaluate the impact of both mild and moderate myopia and different refractive correction methods on certain types of attention of school-age children. Methods: In this prospective case–control study, data was collected from 90 children aged 8 to 10 years old. Participants were classified into three groups based on their spherical lens: mild myopia group (SE: ≤ − 0.50D and > − 3.00D), moderate myopia group (SE: ≤ − 3.00D and > − 6.00D), and control group (SE: ≤ + 0.50D and > − 0.50D). Additionally, children with myopia were subdivided into three subgroups based on refractive correction methods: the uncorrected group, the spectacles corrected group, and the orthokeratology lenses group. The eye-tracking system was used to record and compare attention assessment metrics, including saccade latency, total search time, and saccade accuracy. To enhance result reproducibility, MoCA scale scores were used as a control method to measure attention. Results: When categorized by refraction, MoCA scale scores were lower in the moderate myopia group compared to the control group (p = 0.011). Saccade latency and total search time were slower in both the mild and moderate myopia groups compared to the control group (p < 0.001). A weak positive correlation was observed between spherical lens and total search time (r = 0.260 |
Wajd Amly; Chih-Yang Chen; Hirotaka Onoe; Tadashi Isa Different properties of successful and error saccades in marmosets Journal Article In: Neuroscience Research, vol. 213, pp. 60–71, 2025. @article{Amly2025,Various oculomotor tasks have been used to study eye movements, cognitive control, attention, and neurological disorders. Typically, analysis focuses on successful trials, where the saccade lands very close to the intended target, in both humans or non-human primates (NHPs). Error trials, in which the saccade fails to land on the intended target, are often excluded from these analyses. In this study, we hypothesized that saccades contain information that can predict whether they will result in success or not. We collected data from common marmosets performing the gap saccade task and the oculomotor delayed response task. Successful saccades in both tasks were characterized by higher peak velocities, shorter durations, and shorter latencies compared to errant saccades, regardless of whether the amplitudes were matched or not. These results were further validated using a generalized linear model, with saccade velocity, duration, and latency as predictors. The model demonstrated high accuracy in distinguishing between behavioural outcomes. Our findings suggest that the likelihood of a saccadic eye movement leading to a successful outcome may be predetermined, potentially reflecting the interaction between cognitive processes and saccade programming. |
Lingyue Chen; Lukasz Grzeczkowski; Hermann J. Müller; Zhuanghua Shi Saccade-induced temporal distortion: Opposing effects of time expansion and compression Journal Article In: Psychological Research, vol. 89, no. 2, pp. 1–14, 2025. @article{Chen2025e,Saccadic eye movements, or saccades, can distort our perception of time, as evidenced by the phenomenon of Chronostasis, where the first event after a saccade appears to last longer than it actually does. However, the impact of saccades on events following the first has never been explored. Here, we compared how participants perceived durations of first and second intervals after a saccade with their perceived durations during fixation, where no saccades occurred. We found that saccades lengthened the perceived duration of the first event, confirming Chronostasis. Moreover, when the second event occurred right after the first, its duration was perceived as shorter. Interestingly, when the second event was used as a reference, the Chronostasis effect was even stronger. Notably, this shortening of the second event persisted even when we ruled out processes like the “attentional blink” that might interfere with the timing between the two events. Our findings suggest that saccades induce a brief, uneven distribution of attentional processing in time, leading to an overestimation of the first and an underestimation of the second interval when the two intervals occur close together. |
Steven P. Errington; Jeffrey D. Schall A preparatory cranial potential for saccadic eye movements in macaque monkeys Journal Article In: eNeuro, vol. 12, no. 4, pp. 1–10, 2025. @article{Errington2025,Response preparation is accomplished by gradual accumulation in neural activity until a threshold is reached. In humans, such a preparatory signal, referred to as the lateralized readiness potential (LRP), can be observed in the EEG over sensorimotor cortical areas before execution of a voluntary movement. Although well described for manual movements, less is known about preparatory EEG potentials for saccadic eye movements in humans and nonhuman primates. Hence, we describe a LRP over the frontolateral cortex in macaque monkeys. Homologous to humans, we observed lateralized electrical potentials ramping before the execution of both rewarded and nonrewarded contralateral saccades. This potential parallels the neural spiking of saccadic movement neurons in the frontal eye field (FEF), suggesting that it may offer a noninvasive correlate of intracortical spiking activity. However, unlike neural spiking in the FEF, polarization in frontolateral channels did not distinguish between saccade generation and inhibition. These findings provide new insights into noninvasive electrophysiological signatures of saccadic preparation in nonhuman primates, highlighting the potential of EEG measures to bridge invasive neural recordings and noninvasive studies of eye movement control in humans. |