EyeLink Usability / Applied Publications
All EyeLink usability and applied research publications up until 2020 (with some early 2021s) are listed below by year. You can search the publications using key words such as Driving, Sport, Workload, etc. You can also search for individual author names. If we missed any EyeLink usability or applied article, please email us!
All EyeLink usability and applied publications are also available for download / import into reference management software as a single Bibtex (.bib) file.
2010 |
Lee Richstone; Michael J Schwartz; Casey Seideman; Jeffrey Cadeddu; Sandra P Marshall; Louis R Kavoussi Eye metrics as an objective assessment of surgical skill Journal Article Annals of Surgery, 252 (1), pp. 177–182, 2010. @article{Richstone2010, title = {Eye metrics as an objective assessment of surgical skill}, author = {Lee Richstone and Michael J Schwartz and Casey Seideman and Jeffrey Cadeddu and Sandra P Marshall and Louis R Kavoussi}, doi = {10.1097/SLA.0b013e3181e464fb}, year = {2010}, date = {2010-01-01}, journal = {Annals of Surgery}, volume = {252}, number = {1}, pages = {177--182}, abstract = {OBJECTIVE: Currently, surgical skills assessment relies almost exclusively on subjective measures, which are susceptible to multiple biases. We investigate the use of eye metrics as an objective tool for assessment of surgical skill. SUMMARY BACKGROUND DATA: Eye tracking has helped elucidate relationships between eye movements, visual attention, and insight, all of which are employed during complex task performance (Kowler and Martins, Science. 1982;215:997-999; Tanenhaus et al, Science. 1995;268:1632-1634; Thomas and Lleras, Psychon Bull Rev. 2007;14:663-668; Thomas and Lleras, Cognition. 2009;111:168-174; Schriver et al, Hum Factors. 2008;50:864-878; Kahneman, Attention and Effort. 1973). Discovery of associations between characteristic eye movements and degree of cognitive effort have also enhanced our appreciation of the learning process. METHODS: Using linear discriminate analysis (LDA) and nonlinear neural network analyses (NNA) to classify surgeons into expert and nonexpert cohorts, we examine the relationship between complex eye and pupillary movements, collectively referred to as eye metrics, and surgical skill level. RESULTS: Twenty-one surgeons participated in the simulated and live surgical environments. In the simulated surgical setting, LDA and NNA were able to correctly classify surgeons as expert or nonexpert with 91.9% and 92.9% accuracy, respectively. In the live operating room setting, LDA and NNA were able to correctly classify surgeons as expert or nonexpert with 81.0% and 90.7% accuracy, respectively. CONCLUSIONS: We demonstrate, in simulated and live-operating environments, that eye metrics can reliably distinguish nonexpert from expert surgeons. As current medical educators rely on subjective measures of surgical skill, eye metrics may serve as the basis for objective assessment in surgical education and credentialing in the future. Further development of this potential educational tool is warranted to assess its ability to both reliably classify larger groups of surgeons and follow progression of surgical skill during postgraduate training.}, keywords = {}, pubstate = {published}, tppubtype = {article} } OBJECTIVE: Currently, surgical skills assessment relies almost exclusively on subjective measures, which are susceptible to multiple biases. We investigate the use of eye metrics as an objective tool for assessment of surgical skill. SUMMARY BACKGROUND DATA: Eye tracking has helped elucidate relationships between eye movements, visual attention, and insight, all of which are employed during complex task performance (Kowler and Martins, Science. 1982;215:997-999; Tanenhaus et al, Science. 1995;268:1632-1634; Thomas and Lleras, Psychon Bull Rev. 2007;14:663-668; Thomas and Lleras, Cognition. 2009;111:168-174; Schriver et al, Hum Factors. 2008;50:864-878; Kahneman, Attention and Effort. 1973). Discovery of associations between characteristic eye movements and degree of cognitive effort have also enhanced our appreciation of the learning process. METHODS: Using linear discriminate analysis (LDA) and nonlinear neural network analyses (NNA) to classify surgeons into expert and nonexpert cohorts, we examine the relationship between complex eye and pupillary movements, collectively referred to as eye metrics, and surgical skill level. RESULTS: Twenty-one surgeons participated in the simulated and live surgical environments. In the simulated surgical setting, LDA and NNA were able to correctly classify surgeons as expert or nonexpert with 91.9% and 92.9% accuracy, respectively. In the live operating room setting, LDA and NNA were able to correctly classify surgeons as expert or nonexpert with 81.0% and 90.7% accuracy, respectively. CONCLUSIONS: We demonstrate, in simulated and live-operating environments, that eye metrics can reliably distinguish nonexpert from expert surgeons. As current medical educators rely on subjective measures of surgical skill, eye metrics may serve as the basis for objective assessment in surgical education and credentialing in the future. Further development of this potential educational tool is warranted to assess its ability to both reliably classify larger groups of surgeons and follow progression of surgical skill during postgraduate training. |
Chris M R Smerecnik; Ilse Mesters; Loes T E Kessels; Robert A C Ruiter; Nanne K De Vries; Hein De Vries Risk Analysis, 30 (9), pp. 1387–1398, 2010. @article{Smerecnik2010, title = {Understanding the positive effects of graphical risk information on comprehension: Measuring attention directed to written, tabular, and graphical risk information}, author = {Chris M R Smerecnik and Ilse Mesters and Loes T E Kessels and Robert A C Ruiter and Nanne K {De Vries} and Hein {De Vries}}, doi = {10.1111/j.1539-6924.2010.01435.x}, year = {2010}, date = {2010-01-01}, journal = {Risk Analysis}, volume = {30}, number = {9}, pages = {1387--1398}, abstract = {Risk communications are an integral aspect of health education and promotion. However, the commonly used textual risk information is relatively difficult to understand for the average recipient. Consequently, researchers and health promoters have started to focus on so-called decision aids, such as tables and graphs. Although tabular and graphical risk information more effectively communicate risks than textual risk information, the cognitive mechanisms responsible for this enhancement are unclear. This study aimed to examine two possible mechanisms (i.e., cognitive workload and attention). Cognitive workload (mean pupil size and peak pupil dilation) and attention directed to the risk information (viewing time, number of eye fixations, and eye fixation durations) were both measured in a between-subjects experimental design. The results suggest that graphical risk information facilitates comprehension of that information because it attracts and holds attention for a longer period of time than textual risk information. Graphs are thus a valuable asset to risk communication practice for two reasons: first, they tend to attract attention and, second, when attended to, they elicit information extraction with relatively little cognitive effort, and finally result in better comprehension.}, keywords = {}, pubstate = {published}, tppubtype = {article} } Risk communications are an integral aspect of health education and promotion. However, the commonly used textual risk information is relatively difficult to understand for the average recipient. Consequently, researchers and health promoters have started to focus on so-called decision aids, such as tables and graphs. Although tabular and graphical risk information more effectively communicate risks than textual risk information, the cognitive mechanisms responsible for this enhancement are unclear. This study aimed to examine two possible mechanisms (i.e., cognitive workload and attention). Cognitive workload (mean pupil size and peak pupil dilation) and attention directed to the risk information (viewing time, number of eye fixations, and eye fixation durations) were both measured in a between-subjects experimental design. The results suggest that graphical risk information facilitates comprehension of that information because it attracts and holds attention for a longer period of time than textual risk information. Graphs are thus a valuable asset to risk communication practice for two reasons: first, they tend to attract attention and, second, when attended to, they elicit information extraction with relatively little cognitive effort, and finally result in better comprehension. |
Matt Canham; Mary Hegarty Effects of knowledge and display design on comprehension of complex graphics Journal Article Learning and Instruction, 20 (2), pp. 155–166, 2010. @article{Canham2010, title = {Effects of knowledge and display design on comprehension of complex graphics}, author = {Matt Canham and Mary Hegarty}, doi = {10.1016/j.learninstruc.2009.02.014}, year = {2010}, date = {2010-01-01}, journal = {Learning and Instruction}, volume = {20}, number = {2}, pages = {155--166}, publisher = {Elsevier Ltd}, abstract = {In two experiments, participants made inferences from weather maps, before and after they received instruction about relevant meteorological principles. Different versions of the maps showed either task-relevant information alone, or both task-relevant and task-irrelevant information. Participants improved on the inference task after instruction, indicating that they could apply newly acquired declarative knowledge to make inferences from graphics. In Experiment 1, participants spent more time viewing task-relevant information and less time viewing task-irrelevant information after instruction, and in Experiment 2, the presence of task-irrelevant information impaired performance. These results show that domain knowledge can affect information selection and encoding from complex graphics as well as processes of interpreting and making inferences from the encoded information. They also provide validation of one principle for the design of effective graphical displays, namely that graphics should not display more information than is required for the task at hand.}, keywords = {}, pubstate = {published}, tppubtype = {article} } In two experiments, participants made inferences from weather maps, before and after they received instruction about relevant meteorological principles. Different versions of the maps showed either task-relevant information alone, or both task-relevant and task-irrelevant information. Participants improved on the inference task after instruction, indicating that they could apply newly acquired declarative knowledge to make inferences from graphics. In Experiment 1, participants spent more time viewing task-relevant information and less time viewing task-irrelevant information after instruction, and in Experiment 2, the presence of task-irrelevant information impaired performance. These results show that domain knowledge can affect information selection and encoding from complex graphics as well as processes of interpreting and making inferences from the encoded information. They also provide validation of one principle for the design of effective graphical displays, namely that graphics should not display more information than is required for the task at hand. |
Jean Carletta; Robin L Hill; Craig Nicol; Tim Taylor; Jan Peter de Ruiter; Ellen Gurman Bard Eyetracking for two-person tasks with manipulation of a virtual world Journal Article Behavior Research Methods, 42 (1), pp. 254–265, 2010. @article{Carletta2010, title = {Eyetracking for two-person tasks with manipulation of a virtual world}, author = {Jean Carletta and Robin L Hill and Craig Nicol and Tim Taylor and Jan Peter de Ruiter and Ellen Gurman Bard}, doi = {10.3758/BRM.42.1.254}, year = {2010}, date = {2010-01-01}, journal = {Behavior Research Methods}, volume = {42}, number = {1}, pages = {254--265}, abstract = {Eyetracking facilities are typically restricted to monitoring a single person viewing static images or pre-recorded video. In the present article, we describe a system that makes it possible to study visual attention in coordination with other activity during joint action. The software links two eyetracking systems in parallel and provides an on-screen task. By locating eye movements against dynamic screen regions, it permits automatic tracking of moving on-screen objects. Using existing SR technology, the system can also cross-project each participant's eyetrack and mouse location onto the other's on-screen work space. Keeping a complete record of eyetrack and on-screen events in the same format as subsequent human coding, the system permits the analysis of multiple modalities. The software offers new approaches to spontaneous multimodal communication: joint action and joint attention. These capacities are demonstrated using an experimental paradigm for cooperative on-screen assembly of a two-dimensional model. The software is available under an open source license.}, keywords = {}, pubstate = {published}, tppubtype = {article} } Eyetracking facilities are typically restricted to monitoring a single person viewing static images or pre-recorded video. In the present article, we describe a system that makes it possible to study visual attention in coordination with other activity during joint action. The software links two eyetracking systems in parallel and provides an on-screen task. By locating eye movements against dynamic screen regions, it permits automatic tracking of moving on-screen objects. Using existing SR technology, the system can also cross-project each participant's eyetrack and mouse location onto the other's on-screen work space. Keeping a complete record of eyetrack and on-screen events in the same format as subsequent human coding, the system permits the analysis of multiple modalities. The software offers new approaches to spontaneous multimodal communication: joint action and joint attention. These capacities are demonstrated using an experimental paradigm for cooperative on-screen assembly of a two-dimensional model. The software is available under an open source license. |
David P Crabb; Nicholas D Smith; Franziska G Rauscher; Catharine M Chisholm; John L Barbur; David F Edgar; David F Garway-Heath Exploring eye movements in patients with glaucoma when viewing a driving scene Journal Article PLoS ONE, 5 (3), pp. e9710, 2010. @article{Crabb2010, title = {Exploring eye movements in patients with glaucoma when viewing a driving scene}, author = {David P Crabb and Nicholas D Smith and Franziska G Rauscher and Catharine M Chisholm and John L Barbur and David F Edgar and David F Garway-Heath}, doi = {10.1371/journal.pone.0009710}, year = {2010}, date = {2010-01-01}, journal = {PLoS ONE}, volume = {5}, number = {3}, pages = {e9710}, abstract = {BACKGROUND: Glaucoma is a progressive eye disease and a leading cause of visual disability. Automated assessment of the visual field determines the different stages in the disease process: it would be desirable to link these measurements taken in the clinic with patient's actual function, or establish if patients compensate for their restricted field of view when performing everyday tasks. Hence, this study investigated eye movements in glaucomatous patients when viewing driving scenes in a hazard perception test (HPT). METHODOLOGY/PRINCIPAL FINDINGS: The HPT is a component of the UK driving licence test consisting of a series of short film clips of various traffic scenes viewed from the driver's perspective each containing hazardous situations that require the camera car to change direction or slow down. Data from nine glaucomatous patients with binocular visual field defects and ten age-matched control subjects were considered (all experienced drivers). Each subject viewed 26 different films with eye movements simultaneously monitored by an eye tracker. Computer software was purpose written to pre-process the data, co-register it to the film clips and to quantify eye movements and point-of-regard (using a dynamic bivariate contour ellipse analysis). On average, and across all HPT films, patients exhibited different eye movement characteristics to controls making, for example, significantly more saccades (Ptextless0.001; 95% confidence interval for mean increase: 9.2 to 22.4%). Whilst the average region of 'point-of-regard' of the patients did not differ significantly from the controls, there were revealing cases where patients failed to see a hazard in relation to their binocular visual field defect. CONCLUSIONS/SIGNIFICANCE: Characteristics of eye movement patterns in patients with bilateral glaucoma can differ significantly from age-matched controls when viewing a traffic scene. Further studies of eye movements made by glaucomatous patients could provide useful information about the definition of the visual field component required for fitness to drive.}, keywords = {}, pubstate = {published}, tppubtype = {article} } BACKGROUND: Glaucoma is a progressive eye disease and a leading cause of visual disability. Automated assessment of the visual field determines the different stages in the disease process: it would be desirable to link these measurements taken in the clinic with patient's actual function, or establish if patients compensate for their restricted field of view when performing everyday tasks. Hence, this study investigated eye movements in glaucomatous patients when viewing driving scenes in a hazard perception test (HPT). METHODOLOGY/PRINCIPAL FINDINGS: The HPT is a component of the UK driving licence test consisting of a series of short film clips of various traffic scenes viewed from the driver's perspective each containing hazardous situations that require the camera car to change direction or slow down. Data from nine glaucomatous patients with binocular visual field defects and ten age-matched control subjects were considered (all experienced drivers). Each subject viewed 26 different films with eye movements simultaneously monitored by an eye tracker. Computer software was purpose written to pre-process the data, co-register it to the film clips and to quantify eye movements and point-of-regard (using a dynamic bivariate contour ellipse analysis). On average, and across all HPT films, patients exhibited different eye movement characteristics to controls making, for example, significantly more saccades (Ptextless0.001; 95% confidence interval for mean increase: 9.2 to 22.4%). Whilst the average region of 'point-of-regard' of the patients did not differ significantly from the controls, there were revealing cases where patients failed to see a hazard in relation to their binocular visual field defect. CONCLUSIONS/SIGNIFICANCE: Characteristics of eye movement patterns in patients with bilateral glaucoma can differ significantly from age-matched controls when viewing a traffic scene. Further studies of eye movements made by glaucomatous patients could provide useful information about the definition of the visual field component required for fitness to drive. |
Rong-Fuh Day Examining the validity of the Needleman-Wunsch algorithm in identifying decision strategy with eye-movement data Journal Article Decision Support Systems, 49 (4), pp. 396–403, 2010. @article{Day2010, title = {Examining the validity of the Needleman-Wunsch algorithm in identifying decision strategy with eye-movement data}, author = {Rong-Fuh Day}, doi = {10.1016/j.dss.2010.05.001}, year = {2010}, date = {2010-01-01}, journal = {Decision Support Systems}, volume = {49}, number = {4}, pages = {396--403}, publisher = {Elsevier B.V.}, abstract = {A new generation of eye trackers shows us a promising alternative approach to tracing decision processes beyond the popular computerized-information-board approach. In order to exploit the eye-movement data, this study examined the validity of the Needleman-Wunsch algorithm (NWA) to characterize the decision process, and proposed an NWA-based classification method to predict which typical strategy an empirical search behavior might belong to. An eye-tracking based experiment was conducted. Our results showed that the resemblance score by NWA conformed to the assumption that the pair of information search behaviors based on the same strategy should have the closest resemblance. Moreover, with respect to our NWA-based classification method, our result showed that its overall prediction accuracy, hit-ratio, in identifying underlying strategies achieved 88%, significantly much higher than that gained from chance. On the whole, the combination of eye-fixation data and our NWA-based classification method is qualified.}, keywords = {}, pubstate = {published}, tppubtype = {article} } A new generation of eye trackers shows us a promising alternative approach to tracing decision processes beyond the popular computerized-information-board approach. In order to exploit the eye-movement data, this study examined the validity of the Needleman-Wunsch algorithm (NWA) to characterize the decision process, and proposed an NWA-based classification method to predict which typical strategy an empirical search behavior might belong to. An eye-tracking based experiment was conducted. Our results showed that the resemblance score by NWA conformed to the assumption that the pair of information search behaviors based on the same strategy should have the closest resemblance. Moreover, with respect to our NWA-based classification method, our result showed that its overall prediction accuracy, hit-ratio, in identifying underlying strategies achieved 88%, significantly much higher than that gained from chance. On the whole, the combination of eye-fixation data and our NWA-based classification method is qualified. |
Leandro Luigi Di Stasi; Mauro Marchitto; Adoracíon Antolí; Thierry Baccino; José J Cañas Approximation of on-line mental workload index in ATC simulated multitasks Journal Article Journal of Air Transport Management, 16 (6), pp. 330–333, 2010. @article{DiStasi2010, title = {Approximation of on-line mental workload index in ATC simulated multitasks}, author = {Leandro Luigi {Di Stasi} and Mauro Marchitto and Adoracíon Antolí and Thierry Baccino and José J Ca{ñ}as}, doi = {10.1016/j.jairtraman.2010.02.004}, year = {2010}, date = {2010-01-01}, journal = {Journal of Air Transport Management}, volume = {16}, number = {6}, pages = {330--333}, publisher = {Elsevier Ltd}, abstract = {To assess the effects of workload pressures, participants interacted with a modified version of air traffic control simulated tasks requiring different levels of cognitive resources. Changes in mental workload between the levels were evaluated multidimensionally using a subjective rating, performance in a secondary task, and other behavioural indices. Saccadic movements were measured using a video-based eye tracking system. The Wickens multiple resource model is used as a theoretical reference framework. Saccadic peak velocity decreases with increasing cognitive load, in agreement with subjective test scores and performance data. That saccadic peak velocity is sensitive to variations in mental workload during ecologically valid tasks is demonstrated.}, keywords = {}, pubstate = {published}, tppubtype = {article} } To assess the effects of workload pressures, participants interacted with a modified version of air traffic control simulated tasks requiring different levels of cognitive resources. Changes in mental workload between the levels were evaluated multidimensionally using a subjective rating, performance in a secondary task, and other behavioural indices. Saccadic movements were measured using a video-based eye tracking system. The Wickens multiple resource model is used as a theoretical reference framework. Saccadic peak velocity decreases with increasing cognitive load, in agreement with subjective test scores and performance data. That saccadic peak velocity is sensitive to variations in mental workload during ecologically valid tasks is demonstrated. |
Leandro Luigi Di Stasi; Rebekka Renner; Peggy Staehr; Jens R Helmert; Boris M Velichkovsky; Jose J Canas; Andrés Catena; Sebastian Pannasch Saccadic Peak Velocity Sensitivity to Variations in Mental Workload Journal Article Aviation Space and Environmental Medicine, 81 (4), pp. 413–417, 2010. @article{DiStasi2010a, title = {Saccadic Peak Velocity Sensitivity to Variations in Mental Workload}, author = {Leandro Luigi {Di Stasi} and Rebekka Renner and Peggy Staehr and Jens R Helmert and Boris M Velichkovsky and Jose J Canas and Andrés Catena and Sebastian Pannasch}, doi = {10.3357/ASEM.2579.2010}, year = {2010}, date = {2010-01-01}, journal = {Aviation Space and Environmental Medicine}, volume = {81}, number = {4}, pages = {413--417}, abstract = {Introduction: For research and applications in the field of (neuro)ergonomics, it is of increasing importance to have reliable methods for measuring mental workload. In the present study we examined the hypothesis that saccadic eye movements can be used for an online assessment of mental workload. Methods: Saccadic main sequence (amplitude, dura- tion and peak velocity) was used as a diagnostic measure of mental workload in a virtual driving task with three complexity levels. We tested 18 drivers in the SIRCA driving simulator while their eye movements were recorded. The Wickens' multiple resources model was used as theoretical framework. Changes in mental workload between the complexity levels were evaluated multidimensionally, using subjective rating, performance in a secondary task, and other behavioral indices. Results: Saccadic peak velocity decreased (7.2 visual °/s) as the mental workload increased, as measured by scores of mental workload test (15.2 scores) and the increase of the reaction time on the secondary task (46 ms). Discussion: Saccadic peak velocity is affected by variations in mental workload during ecologically valid tasks. We conclude that saccadic peak velocity could be a useful diagnostic index for the assessment of operators' mental workload and attentional state in hazardous environments.}, keywords = {}, pubstate = {published}, tppubtype = {article} } Introduction: For research and applications in the field of (neuro)ergonomics, it is of increasing importance to have reliable methods for measuring mental workload. In the present study we examined the hypothesis that saccadic eye movements can be used for an online assessment of mental workload. Methods: Saccadic main sequence (amplitude, dura- tion and peak velocity) was used as a diagnostic measure of mental workload in a virtual driving task with three complexity levels. We tested 18 drivers in the SIRCA driving simulator while their eye movements were recorded. The Wickens' multiple resources model was used as theoretical framework. Changes in mental workload between the complexity levels were evaluated multidimensionally, using subjective rating, performance in a secondary task, and other behavioral indices. Results: Saccadic peak velocity decreased (7.2 visual °/s) as the mental workload increased, as measured by scores of mental workload test (15.2 scores) and the increase of the reaction time on the secondary task (46 ms). Discussion: Saccadic peak velocity is affected by variations in mental workload during ecologically valid tasks. We conclude that saccadic peak velocity could be a useful diagnostic index for the assessment of operators' mental workload and attentional state in hazardous environments. |
Mary Hegarty; Matt S Canham; Sara I Fabrikant Thinking about the weather: How display salience and knowledge affect performance in a graphic inference task Journal Article Journal of Experimental Psychology: Learning, Memory, and Cognition, 36 (1), pp. 37–53, 2010. @article{Hegarty2010, title = {Thinking about the weather: How display salience and knowledge affect performance in a graphic inference task}, author = {Mary Hegarty and Matt S Canham and Sara I Fabrikant}, doi = {10.1037/a0017683}, year = {2010}, date = {2010-01-01}, journal = {Journal of Experimental Psychology: Learning, Memory, and Cognition}, volume = {36}, number = {1}, pages = {37--53}, abstract = {Three experiments examined how bottom-up and top-down processes interact when people view and make inferences from complex visual displays (weather maps). Bottom-up effects of display design were investigated by manipulating the relative visual salience of task-relevant and task-irrelevant information across different maps. Top-down effects of domain knowledge were investigated by examining performance and eye fixations before and after participants learned relevant meteorological principles. Map design and knowledge interacted such that salience had no effect on performance before participants learned the meteorological principles; however, after learning, participants were more accurate if they viewed maps that made task-relevant information more visually salient. Effects of display design on task performance were somewhat dissociated from effects of display design on eye fixations. The results support a model in which eye fixations are directed primarily by top-down factors (task and domain knowledge). They suggest that good display design facilitates performance not just by guiding where viewers look in a complex display but also by facilitating processing of the visual features that represent task-relevant information at a given display location.}, keywords = {}, pubstate = {published}, tppubtype = {article} } Three experiments examined how bottom-up and top-down processes interact when people view and make inferences from complex visual displays (weather maps). Bottom-up effects of display design were investigated by manipulating the relative visual salience of task-relevant and task-irrelevant information across different maps. Top-down effects of domain knowledge were investigated by examining performance and eye fixations before and after participants learned relevant meteorological principles. Map design and knowledge interacted such that salience had no effect on performance before participants learned the meteorological principles; however, after learning, participants were more accurate if they viewed maps that made task-relevant information more visually salient. Effects of display design on task performance were somewhat dissociated from effects of display design on eye fixations. The results support a model in which eye fixations are directed primarily by top-down factors (task and domain knowledge). They suggest that good display design facilitates performance not just by guiding where viewers look in a complex display but also by facilitating processing of the visual features that represent task-relevant information at a given display location. |
Constanze Hesse; Tristan T Nakagawa; Heiner Deubel Bimanual movement control is moderated by fixation strategies Journal Article Experimental Brain Research, 202 (4), pp. 837–850, 2010. @article{Hesse2010, title = {Bimanual movement control is moderated by fixation strategies}, author = {Constanze Hesse and Tristan T Nakagawa and Heiner Deubel}, doi = {10.1007/s00221-010-2189-3}, year = {2010}, date = {2010-01-01}, journal = {Experimental Brain Research}, volume = {202}, number = {4}, pages = {837--850}, abstract = {Our study examined the effects of performing a pointing movement with the left hand on the kinematics of a simultaneous grasping movement executed with the right hand. We were especially interested in the question of whether both movements can be controlled independently or whether interference effects occur. Since previous studies suggested that eye movements may play a crucial role in bimanual movement control, the effects of different fixation strategies were also studied. Human participants were either free to move their eyes (Experiment 1) or they had to fixate (Experiment 2) while doing the task. The results show that bimanual movement control differed fundamentally depending on the fixation condition: if free viewing was allowed, participants tended to perform the task sequentially, as reflected in grasping kinematics by a delayed grip opening and a poor adaptation of the grip to the object properties for the duration of the pointing movement. This behavior was accompanied by a serial fixation of the targets for the pointing and grasping movements. In contrast, when central fixation was required, both movements were performed fast and with no obvious interference effects. The results support the notion that bimanual movement control is moderated by fixation strategies. By default, participants seem to prefer a sequential behavior in which the eyes monitor what the hands are doing. However, when forced to fixate, they do surprisingly well in performing both movements in parallel.}, keywords = {}, pubstate = {published}, tppubtype = {article} } Our study examined the effects of performing a pointing movement with the left hand on the kinematics of a simultaneous grasping movement executed with the right hand. We were especially interested in the question of whether both movements can be controlled independently or whether interference effects occur. Since previous studies suggested that eye movements may play a crucial role in bimanual movement control, the effects of different fixation strategies were also studied. Human participants were either free to move their eyes (Experiment 1) or they had to fixate (Experiment 2) while doing the task. The results show that bimanual movement control differed fundamentally depending on the fixation condition: if free viewing was allowed, participants tended to perform the task sequentially, as reflected in grasping kinematics by a delayed grip opening and a poor adaptation of the grip to the object properties for the duration of the pointing movement. This behavior was accompanied by a serial fixation of the targets for the pointing and grasping movements. In contrast, when central fixation was required, both movements were performed fast and with no obvious interference effects. The results support the notion that bimanual movement control is moderated by fixation strategies. By default, participants seem to prefer a sequential behavior in which the eyes monitor what the hands are doing. However, when forced to fixate, they do surprisingly well in performing both movements in parallel. |
Lynn Huestegge; Eva Maria Skottke; Sina Anders; Jochen Müsseler; Günter Debus The development of hazard perception: Dissociation of visual orientation and hazard processing Journal Article Transportation Research Part F: Traffic Psychology and Behaviour, 13 (1), pp. 1–8, 2010. @article{Huestegge2010e, title = {The development of hazard perception: Dissociation of visual orientation and hazard processing}, author = {Lynn Huestegge and Eva Maria Skottke and Sina Anders and Jochen Müsseler and Günter Debus}, doi = {10.1016/j.trf.2009.09.005}, year = {2010}, date = {2010-01-01}, journal = {Transportation Research Part F: Traffic Psychology and Behaviour}, volume = {13}, number = {1}, pages = {1--8}, publisher = {Elsevier Ltd}, abstract = {Eye movements are a key behavior for visual information processing in traffic situations and for vehicle control. Previous research showed that effective ways of eye guidance are related to better hazard perception skills. Furthermore, hazard perception is reported to be faster for experienced drivers as compared to novice drivers. However, little is known whether this difference can be attributed to the development of visual orientation, or hazard processing. In the present study, we compared eye movements of 20 inexperienced and 20 experienced drivers in a hazard perception task. We separately measured (a) the interval between the onset of a static hazard scene and the first fixation on a potential hazard, and (b) the interval between the first fixation on a potential hazard and the final response. While overall RT was faster for experienced compared to inexperienced drivers, the scanning patterns revealed that this difference was due to faster processing after the initial fixation on the hazard, whereas scene scanning times until the initial fixation on the hazard did not differ between groups. textcopyright 2009 Elsevier Ltd. All rights reserved.}, keywords = {}, pubstate = {published}, tppubtype = {article} } Eye movements are a key behavior for visual information processing in traffic situations and for vehicle control. Previous research showed that effective ways of eye guidance are related to better hazard perception skills. Furthermore, hazard perception is reported to be faster for experienced drivers as compared to novice drivers. However, little is known whether this difference can be attributed to the development of visual orientation, or hazard processing. In the present study, we compared eye movements of 20 inexperienced and 20 experienced drivers in a hazard perception task. We separately measured (a) the interval between the onset of a static hazard scene and the first fixation on a potential hazard, and (b) the interval between the first fixation on a potential hazard and the final response. While overall RT was faster for experienced compared to inexperienced drivers, the scanning patterns revealed that this difference was due to faster processing after the initial fixation on the hazard, whereas scene scanning times until the initial fixation on the hazard did not differ between groups. textcopyright 2009 Elsevier Ltd. All rights reserved. |
2009 |
Sauman Chu; Nora Paul; Laura Ruel Using eye tracking technology to examine the effectiveness of design elements on news websites Journal Article Information Design Journal, 17 (1), pp. 31–43, 2009. @article{Chu2009, title = {Using eye tracking technology to examine the effectiveness of design elements on news websites}, author = {Sauman Chu and Nora Paul and Laura Ruel}, doi = {10.1075/idj.17.1.04chu}, year = {2009}, date = {2009-01-01}, journal = {Information Design Journal}, volume = {17}, number = {1}, pages = {31--43}, abstract = {Online environments allow for a richer expression for certain design elements. The goal of this collaborative research project is to identify, design, and examine various online news features in order to determine the impact of different digital design combinations on news audiences. Eye tracking was the primary method we used to examine three main areas: navigation for slide shows, effectiveness of breaking news formats, and design options for supplemental links. The project used an applied research approach by taking academically rigorous research and using that to inform and guide industry practice. [ABSTRACT FROM AUTHOR] Copyright of Information Design Journal (IDJ) is the property of John Benjamins Publishing Co. and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract.}, keywords = {}, pubstate = {published}, tppubtype = {article} } Online environments allow for a richer expression for certain design elements. The goal of this collaborative research project is to identify, design, and examine various online news features in order to determine the impact of different digital design combinations on news audiences. Eye tracking was the primary method we used to examine three main areas: navigation for slide shows, effectiveness of breaking news formats, and design options for supplemental links. The project used an applied research approach by taking academically rigorous research and using that to inform and guide industry practice. [ABSTRACT FROM AUTHOR] Copyright of Information Design Journal (IDJ) is the property of John Benjamins Publishing Co. and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. |
Leandro Luigi Di Stasi; Vanessa Álvarez-Valbuena; José J Cañas; Antonio Maldonado; Andrés Catena; Adoración Antolí; Antonio Candido Risk behaviour and mental workload: Multimodal assessment techniques applied to motorbike riding simulation Journal Article Transportation Research Part F: Traffic Psychology and Behaviour, 12 (5), pp. 361–370, 2009. @article{DiStasi2009, title = {Risk behaviour and mental workload: Multimodal assessment techniques applied to motorbike riding simulation}, author = {Leandro Luigi {Di Stasi} and Vanessa Álvarez-Valbuena and José J Ca{ñ}as and Antonio Maldonado and Andrés Catena and Adoración Antolí and Antonio Candido}, doi = {10.1016/j.trf.2009.02.004}, year = {2009}, date = {2009-01-01}, journal = {Transportation Research Part F: Traffic Psychology and Behaviour}, volume = {12}, number = {5}, pages = {361--370}, abstract = {We present data from an ongoing research project on the cognitive, emotional and neuropsychological basis of risk behaviour. The main aim of the project is to build a model of risk behaviour so that if we know certain cognitive, behavioural and emotional variables, we will be able to predict decisions made in the face of uncertainty and risk, with the final goal of designing programs for evaluating, preventing and controlling risk behaviour. The objective of the present study was to look for individual differences in hazard perception during a static riding simulation and their relationship with mental workload. We used a multidimensional methodology, including behavioural, subjective and physiological data. The behavioural measures were obtained in a static riding simulation during eight hazard situations. We evaluated whether eye activity measures correlated with cognitive workload and different types of risky behaviours. Eye movement parameters were measured using a video-based eye tracking system. We found that risk-prone individuals showed specific patterns of risky behaviours and that peak of saccadic velocity and subjective mental workload indexes were both reliable indicators of risk proneness. Mental workload was higher for participants showing attitudes to risk behaviours probably because of a lack of conscious awareness of specific cues indicating dangerous scenarios.}, keywords = {}, pubstate = {published}, tppubtype = {article} } We present data from an ongoing research project on the cognitive, emotional and neuropsychological basis of risk behaviour. The main aim of the project is to build a model of risk behaviour so that if we know certain cognitive, behavioural and emotional variables, we will be able to predict decisions made in the face of uncertainty and risk, with the final goal of designing programs for evaluating, preventing and controlling risk behaviour. The objective of the present study was to look for individual differences in hazard perception during a static riding simulation and their relationship with mental workload. We used a multidimensional methodology, including behavioural, subjective and physiological data. The behavioural measures were obtained in a static riding simulation during eight hazard situations. We evaluated whether eye activity measures correlated with cognitive workload and different types of risky behaviours. Eye movement parameters were measured using a video-based eye tracking system. We found that risk-prone individuals showed specific patterns of risky behaviours and that peak of saccadic velocity and subjective mental workload indexes were both reliable indicators of risk proneness. Mental workload was higher for participants showing attitudes to risk behaviours probably because of a lack of conscious awareness of specific cues indicating dangerous scenarios. |
Jamal K Mansour; R C L Lindsay; Neil Brewer; Kevin G Munhall Characterizing visual behaviour in a lineup task Journal Article Applied Cognitive Psychology, 23 (7), pp. 1012–1026, 2009. @article{Mansour2009, title = {Characterizing visual behaviour in a lineup task}, author = {Jamal K Mansour and R C L Lindsay and Neil Brewer and Kevin G Munhall}, doi = {10.1002/acp.1570}, year = {2009}, date = {2009-01-01}, journal = {Applied Cognitive Psychology}, volume = {23}, number = {7}, pages = {1012--1026}, abstract = {Eye tracking was used to monitor participants' visual behaviour while viewing lineups in order to determine whether gaze behaviour predicted decision accuracy. Participants viewed taped crimes followed by simultaneous lineups. Participants (N¼34) viewed 4 target-present and 4 target-absent lineups. Decision time, number of fixations and duration of fixations differed for selections vs. non- selections. Correct and incorrect selections differed only in terms of comparison-type behaviour involving the selected face. Correct and incorrect non-selections could be distinguished by decision time, number of fixations and duration of fixations on the target or most-attended face and comparisons. Implications of visual behaviour for judgment strategy (relative vs. absolute) are discussed.}, keywords = {}, pubstate = {published}, tppubtype = {article} } Eye tracking was used to monitor participants' visual behaviour while viewing lineups in order to determine whether gaze behaviour predicted decision accuracy. Participants viewed taped crimes followed by simultaneous lineups. Participants (N¼34) viewed 4 target-present and 4 target-absent lineups. Decision time, number of fixations and duration of fixations differed for selections vs. non- selections. Correct and incorrect selections differed only in terms of comparison-type behaviour involving the selected face. Correct and incorrect non-selections could be distinguished by decision time, number of fixations and duration of fixations on the target or most-attended face and comparisons. Implications of visual behaviour for judgment strategy (relative vs. absolute) are discussed. |
Jason S McCarley Effects of speed - accuracy instructions on oculomotor scanning and target recognition in a simulated baggage X-ray screening task Journal Article Ergonomics, 52 (3), pp. 325–333, 2009. @article{McCarley2009, title = {Effects of speed - accuracy instructions on oculomotor scanning and target recognition in a simulated baggage X-ray screening task}, author = {Jason S McCarley}, doi = {10.1080/00140130802376059}, year = {2009}, date = {2009-01-01}, journal = {Ergonomics}, volume = {52}, number = {3}, pages = {325--333}, abstract = {Visual search tasks are often carried out under high levels of time stress. Transportation security screeners, for example, face demands to achieve high levels of accuracy while maintaining rapid passenger throughput. An experiment examined the strategies by which operators regulate visual search performance under such conditions. Observers performed a simulated baggage-screening task under instructions to emphasise either response speed or accuracy. Behavioural measures and eye movements were recorded. Observers made fewer and briefer fixations under emphasise-speed than under emphasise-accuracy instructions. Losses in accuracy were produced by more frequent failures to fixate on targets and a decrease in the detection rate of non-fixated targets. The likelihood with which observers detected a fixated target was similar across speed-accuracy instructions. Results will inform efforts to model visual search in naturalistic tasks, allowing more accurate prediction of response times and error rate and may aid the design of training programmes and other interventions to improve search performance under stress.}, keywords = {}, pubstate = {published}, tppubtype = {article} } Visual search tasks are often carried out under high levels of time stress. Transportation security screeners, for example, face demands to achieve high levels of accuracy while maintaining rapid passenger throughput. An experiment examined the strategies by which operators regulate visual search performance under such conditions. Observers performed a simulated baggage-screening task under instructions to emphasise either response speed or accuracy. Behavioural measures and eye movements were recorded. Observers made fewer and briefer fixations under emphasise-speed than under emphasise-accuracy instructions. Losses in accuracy were produced by more frequent failures to fixate on targets and a decrease in the detection rate of non-fixated targets. The likelihood with which observers detected a fixated target was similar across speed-accuracy instructions. Results will inform efforts to model visual search in naturalistic tasks, allowing more accurate prediction of response times and error rate and may aid the design of training programmes and other interventions to improve search performance under stress. |
Michael Rohs; Robert Schleicher; Johannes Schöning; Georg Essl; Anja Naumann; Antonio Krüger Impact of item density on the utility of visual context in magic lens interactions Journal Article Personal and Ubiquitous Computing, 13 (8), pp. 633–646, 2009. @article{Rohs2009, title = {Impact of item density on the utility of visual context in magic lens interactions}, author = {Michael Rohs and Robert Schleicher and Johannes Schöning and Georg Essl and Anja Naumann and Antonio Krüger}, doi = {10.1007/s00779-009-0247-2}, year = {2009}, date = {2009-01-01}, journal = {Personal and Ubiquitous Computing}, volume = {13}, number = {8}, pages = {633--646}, abstract = {This article reports on two user studies investi- gating the effect of visual context in handheld augmented reality interfaces.Adynamic peephole interface (without vi- sual context beyond the device display) was compared to a magic lens interface (with video see-through augmentation of external visual context). The task was to explore items on a map and look for a specific attribute. We tested dif- ferent sizes of visual context as well as different numbers of items per area, i.e. different item densities. Hand motion patterns and eye movements were recorded. We found that visual context is most effective for sparsely distributed items and gets less helpful with increasing item density. User per- formance in the magic lens case is generally better than in the dynamic peephole case, but approaches the performance of the latter the more densely the items are spaced. In all conditions, subjective feedback indicates that participants generally prefer visual context over the lack thereof. The insights gained from this study are relevant for designers of mobile AR and dynamic peephole interfaces, involving spa- tially tracked personal displays or combined personal and public displays, by suggesting when to use visual context.}, keywords = {}, pubstate = {published}, tppubtype = {article} } This article reports on two user studies investi- gating the effect of visual context in handheld augmented reality interfaces.Adynamic peephole interface (without vi- sual context beyond the device display) was compared to a magic lens interface (with video see-through augmentation of external visual context). The task was to explore items on a map and look for a specific attribute. We tested dif- ferent sizes of visual context as well as different numbers of items per area, i.e. different item densities. Hand motion patterns and eye movements were recorded. We found that visual context is most effective for sparsely distributed items and gets less helpful with increasing item density. User per- formance in the magic lens case is generally better than in the dynamic peephole case, but approaches the performance of the latter the more densely the items are spaced. In all conditions, subjective feedback indicates that participants generally prefer visual context over the lack thereof. The insights gained from this study are relevant for designers of mobile AR and dynamic peephole interfaces, involving spa- tially tracked personal displays or combined personal and public displays, by suggesting when to use visual context. |
Ladislao Salmerón; Thierry Baccino; José J Cañas; Rafael I Madrid; Inmaculada Fajardo Do graphical overviews facilitate or hinder comprehension in hypertext? Journal Article Computers and Education, 53 (4), pp. 1308–1319, 2009. @article{Salmeron2009, title = {Do graphical overviews facilitate or hinder comprehension in hypertext?}, author = {Ladislao Salmerón and Thierry Baccino and José J Ca{ñ}as and Rafael I Madrid and Inmaculada Fajardo}, doi = {10.1016/j.compedu.2009.06.013}, year = {2009}, date = {2009-01-01}, journal = {Computers and Education}, volume = {53}, number = {4}, pages = {1308--1319}, publisher = {Elsevier Ltd}, abstract = {Educational hypertexts usually include graphical overviews, conveying the structure of the text schematically with the aim of fostering comprehension. Despite the claims about their relevance, there is currently no consensus on the impact that hypertext overviews have on the reader's comprehension. In the present paper we have explored how hypertext overviews might affect comprehension with regard to (a) the time at which students read the overview and (b) the hypertext difficulty. The results from two eye-tracking studies revealed that reading a graphical overview at the beginning of the hypertext is related to an improvement in the participant's comprehension of quite difficult hypertexts, whereas reading an overview at the end of the hypertext is linked to a decrease in the student's comprehension of easier hypertexts. These findings are interpreted in light of the Assimilation Theory and the Active Processing model. Finally, the key educational and hypertext design implications of the results are discussed.}, keywords = {}, pubstate = {published}, tppubtype = {article} } Educational hypertexts usually include graphical overviews, conveying the structure of the text schematically with the aim of fostering comprehension. Despite the claims about their relevance, there is currently no consensus on the impact that hypertext overviews have on the reader's comprehension. In the present paper we have explored how hypertext overviews might affect comprehension with regard to (a) the time at which students read the overview and (b) the hypertext difficulty. The results from two eye-tracking studies revealed that reading a graphical overview at the beginning of the hypertext is related to an improvement in the participant's comprehension of quite difficult hypertexts, whereas reading an overview at the end of the hypertext is linked to a decrease in the student's comprehension of easier hypertexts. These findings are interpreted in light of the Assimilation Theory and the Active Processing model. Finally, the key educational and hypertext design implications of the results are discussed. |
Oleg Špakov; Päivi Majaranta Scrollable keyboards for casual eye typing Journal Article PsychNology Journal, 7 (2), pp. 159–173, 2009. @article{Spakov2009, title = {Scrollable keyboards for casual eye typing}, author = {Oleg {Š}pakov and Päivi Majaranta}, doi = {10.1017/CBO9781107415324.004}, year = {2009}, date = {2009-01-01}, journal = {PsychNology Journal}, volume = {7}, number = {2}, pages = {159--173}, abstract = {In eye typing, a full on-screen keyboard often takes a lot of space because the inaccuracy in eye tracking requires big keys. We propose “scrollable keyboards” where one or more rows are hidden to save space. Results from an experiment with 8 expert participants show that the typing speed reduced by 51.4% for a 1-row keyboard and 25.3% for a 2-row keyboard compared to a full (3-row) QWERTY. By optimizing the keyboard layout according to letter- to-letter probabilities we were able to reduce the scroll button usage, which further increased the typing speed from 7.26 wpm (QWERTY) to 8.86 wpm (optimized layout) on the 1-row keyboard, and from 11.17 wpm to 12.18 wpm on the 2-row keyboard, respectively}, keywords = {}, pubstate = {published}, tppubtype = {article} } In eye typing, a full on-screen keyboard often takes a lot of space because the inaccuracy in eye tracking requires big keys. We propose “scrollable keyboards” where one or more rows are hidden to save space. Results from an experiment with 8 expert participants show that the typing speed reduced by 51.4% for a 1-row keyboard and 25.3% for a 2-row keyboard compared to a full (3-row) QWERTY. By optimizing the keyboard layout according to letter- to-letter probabilities we were able to reduce the scroll button usage, which further increased the typing speed from 7.26 wpm (QWERTY) to 8.86 wpm (optimized layout) on the 1-row keyboard, and from 11.17 wpm to 12.18 wpm on the 2-row keyboard, respectively |
Åsa Wengelin; Mark Torrance; Kenneth Holmqvist; Sol Simpson; David Galbraith; Victoria Johansson; Roger Johansson Combined eyetracking and keystroke-logging methods for studying cognitive processes in text production Journal Article Behavior Research Methods, 41 (2), pp. 337–351, 2009. @article{Wengelin2009, title = {Combined eyetracking and keystroke-logging methods for studying cognitive processes in text production}, author = {Åsa Wengelin and Mark Torrance and Kenneth Holmqvist and Sol Simpson and David Galbraith and Victoria Johansson and Roger Johansson}, doi = {10.3758/BRM.41.2.337}, year = {2009}, date = {2009-01-01}, journal = {Behavior Research Methods}, volume = {41}, number = {2}, pages = {337--351}, abstract = {Writers typically spend a certain proportion of time looking back over the text that they have written. This is likely to serve a number of different functions, which are currently poorly understood. In this article, we present two systems, ScriptLog+ TimeLine and EyeWrite, that adopt different and complementary approaches to exploring this activity by collecting and analyzing combined eye movement and keystroke data from writers composing extended texts. ScriptLog+ TimeLine is a system that is based on an existing keystroke-logging program and uses heuristic, pattern-matching methods to identify reading episodes within eye movement data. EyeWrite is an integrated editor and analysis system that permits identification of the words that the writer fixates and their location within the developing text. We demonstrate how the methods instantiated within these systems can be used to make sense of the large amount of data generated by eyetracking and keystroke logging in order to inform understanding of the cognitive processes that underlie written text production.}, keywords = {}, pubstate = {published}, tppubtype = {article} } Writers typically spend a certain proportion of time looking back over the text that they have written. This is likely to serve a number of different functions, which are currently poorly understood. In this article, we present two systems, ScriptLog+ TimeLine and EyeWrite, that adopt different and complementary approaches to exploring this activity by collecting and analyzing combined eye movement and keystroke data from writers composing extended texts. ScriptLog+ TimeLine is a system that is based on an existing keystroke-logging program and uses heuristic, pattern-matching methods to identify reading episodes within eye movement data. EyeWrite is an integrated editor and analysis system that permits identification of the words that the writer fixates and their location within the developing text. We demonstrate how the methods instantiated within these systems can be used to make sense of the large amount of data generated by eyetracking and keystroke logging in order to inform understanding of the cognitive processes that underlie written text production. |
2008 |
Yasuhiro Seya; Hidetoshi Nakayasu; Patrick Patterson Visual search of trained and untrained drivers in a driving simulator Journal Article Japanese Psychological Research, 50 (4), pp. 242–252, 2008. @article{Seya2008, title = {Visual search of trained and untrained drivers in a driving simulator}, author = {Yasuhiro Seya and Hidetoshi Nakayasu and Patrick Patterson}, doi = {10.1111/j.1468-5884.2008.00380.x}, year = {2008}, date = {2008-11-01}, journal = {Japanese Psychological Research}, volume = {50}, number = {4}, pages = {242--252}, abstract = {To investigate the effects of driving experience on visual search during driving, we measured eye movements during driving tasks using a driving simulator. We evaluated trained and untrained drivers for selected driving road section types (for example, intersections and straight roads). Participants in the trained group had received driving training by the simulator before the experiment, while the others had no driving training by it. In the experiment, the participants were instructed to drive safely in the simulator. The results of scan paths showed that eye positions were less variable in the trained group than in the untrained group. Total eye-movement distances were shorter, and fixation durations were longer in the trained group than in the untrained group. These results suggest that trained drivers may perceive relevant information efficiently with few eye movements by using their anticipation skills and useful field of view, which may have been developed through their driving training in the simulator.}, keywords = {}, pubstate = {published}, tppubtype = {article} } To investigate the effects of driving experience on visual search during driving, we measured eye movements during driving tasks using a driving simulator. We evaluated trained and untrained drivers for selected driving road section types (for example, intersections and straight roads). Participants in the trained group had received driving training by the simulator before the experiment, while the others had no driving training by it. In the experiment, the participants were instructed to drive safely in the simulator. The results of scan paths showed that eye positions were less variable in the trained group than in the untrained group. Total eye-movement distances were shorter, and fixation durations were longer in the trained group than in the untrained group. These results suggest that trained drivers may perceive relevant information efficiently with few eye movements by using their anticipation skills and useful field of view, which may have been developed through their driving training in the simulator. |
Keith Rayner; Brett Miller; Caren M Rotello Eye movements when looking at print advertisements: The goal of the viewer matters Journal Article Applied Cognitive Psychology, 22 (5), pp. 697–707, 2008. @article{Rayner2008, title = {Eye movements when looking at print advertisements: The goal of the viewer matters}, author = {Keith Rayner and Brett Miller and Caren M Rotello}, doi = {10.1002/acp.1389}, year = {2008}, date = {2008-01-01}, journal = {Applied Cognitive Psychology}, volume = {22}, number = {5}, pages = {697--707}, abstract = {Viewers looked at print advertisements as their eye movements were recorded. Half of them were asked to rate how much they liked each ad (for convenience, we will generally use the term 'ad' from this point on), while the other half were asked to rate the effectiveness of each ad. Previous research indicated that viewers who were asked to consider purchasing products in the ads looked at the text earlier and more often than the picture part of the ad. In contrast, viewers in the present experiment looked at the picture part of the ad earlier and longer than the text. The results indicate quite clearly that the goal of the viewer very much influences where (and for how long) viewers look at different parts of ads, but also indicate that the nature of the ad per se matters.}, keywords = {}, pubstate = {published}, tppubtype = {article} } Viewers looked at print advertisements as their eye movements were recorded. Half of them were asked to rate how much they liked each ad (for convenience, we will generally use the term 'ad' from this point on), while the other half were asked to rate the effectiveness of each ad. Previous research indicated that viewers who were asked to consider purchasing products in the ads looked at the text earlier and more often than the picture part of the ad. In contrast, viewers in the present experiment looked at the picture part of the ad earlier and longer than the text. The results indicate quite clearly that the goal of the viewer very much influences where (and for how long) viewers look at different parts of ads, but also indicate that the nature of the ad per se matters. |
Brian Sullivan; Jelena Jovancevic-Misic; Mary Hayhoe; Gwen Sterns Use of multiple preferred retinal loci in Stargardt's disease during natural tasks: A case study Journal Article Ophthalmic and Physiological Optics, 28 (2), pp. 168–177, 2008. @article{Sullivan2008, title = {Use of multiple preferred retinal loci in Stargardt's disease during natural tasks: A case study}, author = {Brian Sullivan and Jelena Jovancevic-Misic and Mary Hayhoe and Gwen Sterns}, doi = {10.1111/j.1475-1313.2008.00546.x}, year = {2008}, date = {2008-01-01}, journal = {Ophthalmic and Physiological Optics}, volume = {28}, number = {2}, pages = {168--177}, abstract = {Individuals with central visual field loss often use a preferred retinal locus (PRL) to compensate for their deficit. We present a case study examining the eye movements of a subject with Stargardt's disease causing bilateral central scotomas, while performing a set of natural tasks including: making a sandwich; building a model; reaching and grasping; and catching a ball. In general, the subject preferred to use PRLs in the lower left visual field. However, there was considerable variation in the location and extent of the PRLs used. Our results demonstrate that a well-defined PRL is not necessary to adequately perform this set of tasks and that many sites in the peripheral retina may be viable for PRLs, contingent on task and stimulus constraints.}, keywords = {}, pubstate = {published}, tppubtype = {article} } Individuals with central visual field loss often use a preferred retinal locus (PRL) to compensate for their deficit. We present a case study examining the eye movements of a subject with Stargardt's disease causing bilateral central scotomas, while performing a set of natural tasks including: making a sandwich; building a model; reaching and grasping; and catching a ball. In general, the subject preferred to use PRLs in the lower left visual field. However, there was considerable variation in the location and extent of the PRLs used. Our results demonstrate that a well-defined PRL is not necessary to adequately perform this set of tasks and that many sites in the peripheral retina may be viable for PRLs, contingent on task and stimulus constraints. |
Jens R Helmert; Sebastian Pannasch; Boris M Velichkovsky Influences of dwell time and cursor control on the performance in gaze driven typing Journal Article Journal of Eye Movement Research, 2 (1), pp. 1–8, 2008. @article{Helmert2008, title = {Influences of dwell time and cursor control on the performance in gaze driven typing}, author = {Jens R Helmert and Sebastian Pannasch and Boris M Velichkovsky}, doi = {10.16910/jemr.2.4.3}, year = {2008}, date = {2008-01-01}, journal = {Journal of Eye Movement Research}, volume = {2}, number = {1}, pages = {1--8}, abstract = {In gaze controlled computer interfaces the dwell time is often used as selection criterion. But this solution comes along with several problems, especially in the temporal domain: Eye movement studies on scene perception could demonstrate that fixations of different durations serve different purposes and should therefore be differentiated. The use of dwell time for selection implies the need to distinguish intentional selections from merely per-ceptual processes, described as the Midas touch problem. Moreover, the feedback of the actual own eye position has not yet been addressed to systematic studies in the context of usability in gaze based computer interaction. We present research on the usability of a simple eye typing set up. Different dwell time and eye position feedback configurations were tested. Our results indicate that smoothing raw eye position and temporal delays in visual feedback enhance the system's functionality and usability. Best overall performance was obtained with a dwell time of 500 ms.}, keywords = {}, pubstate = {published}, tppubtype = {article} } In gaze controlled computer interfaces the dwell time is often used as selection criterion. But this solution comes along with several problems, especially in the temporal domain: Eye movement studies on scene perception could demonstrate that fixations of different durations serve different purposes and should therefore be differentiated. The use of dwell time for selection implies the need to distinguish intentional selections from merely per-ceptual processes, described as the Midas touch problem. Moreover, the feedback of the actual own eye position has not yet been addressed to systematic studies in the context of usability in gaze based computer interaction. We present research on the usability of a simple eye typing set up. Different dwell time and eye position feedback configurations were tested. Our results indicate that smoothing raw eye position and temporal delays in visual feedback enhance the system's functionality and usability. Best overall performance was obtained with a dwell time of 500 ms. |
2007 |
Michael L Spezio; Po-Yin Samuel Huang; Fulvia Castelli; Ralph Adolphs Amygdala damage impairs eye contact during conversations with real people Journal Article Journal of Neuroscience, 27 (15), pp. 3994–3997, 2007. @article{Spezio2007bb, title = {Amygdala damage impairs eye contact during conversations with real people}, author = {Michael L Spezio and Po-Yin Samuel Huang and Fulvia Castelli and Ralph Adolphs}, doi = {10.1523/JNEUROSCI.3789-06.2007}, year = {2007}, date = {2007-01-01}, journal = {Journal of Neuroscience}, volume = {27}, number = {15}, pages = {3994--3997}, abstract = {The role of the human amygdala in real social interactions remains essentially unknown, although studies in nonhuman primates and studies using photographs and video in humans have shown it to be critical for emotional processing and suggest its importance for social cognition. We show here that complete amygdala lesions result in a severe reduction in direct eye contact during conversations with real people, together with an abnormal increase in gaze to the mouth. These novel findings from real social interactions are consistent with an hypothesized role for the amygdala in autism and the approach taken here opens up new directions for quantifying social behavior in humans.}, keywords = {}, pubstate = {published}, tppubtype = {article} } The role of the human amygdala in real social interactions remains essentially unknown, although studies in nonhuman primates and studies using photographs and video in humans have shown it to be critical for emotional processing and suggest its importance for social cognition. We show here that complete amygdala lesions result in a severe reduction in direct eye contact during conversations with real people, together with an abnormal increase in gaze to the mouth. These novel findings from real social interactions are consistent with an hypothesized role for the amygdala in autism and the approach taken here opens up new directions for quantifying social behavior in humans. |
Fernando Vilariño; Gerard Lacey; Jiang Zhou; Hugh Mulcahy; Stephen Patchett Automatic labeling of colonoscopy video for cancer detection Journal Article Pattern Recognition and Image Analysis, (1), pp. 290–297, 2007. @article{Vilarino2007, title = {Automatic labeling of colonoscopy video for cancer detection}, author = {Fernando Vilari{ñ}o and Gerard Lacey and Jiang Zhou and Hugh Mulcahy and Stephen Patchett}, doi = {10.1007/978-3-540-72847-4_38}, year = {2007}, date = {2007-01-01}, journal = {Pattern Recognition and Image Analysis}, number = {1}, pages = {290--297}, abstract = {The labeling of large quantities of medical video data by clinicians is a tedious and time consuming task. In addition, the labeling process itself is rigid, since it requires the expert's interaction to classify image contents into a limited number of predetermined categories. This paper describes an architecture to accelerate the labeling step using eye movement tracking data. We report some initial results in training a Support Vector Machine (SVM) to detect cancer polyps in colonoscopy video, and a further analysis of their categories in the feature space using Self Organizing Maps (SOM). Our overall hypothesis is that the clinician's eye will be drawn to the salient features of the image and that sustained fixations will be associated with those features that are associated with disease states.}, keywords = {}, pubstate = {published}, tppubtype = {article} } The labeling of large quantities of medical video data by clinicians is a tedious and time consuming task. In addition, the labeling process itself is rigid, since it requires the expert's interaction to classify image contents into a limited number of predetermined categories. This paper describes an architecture to accelerate the labeling step using eye movement tracking data. We report some initial results in training a Support Vector Machine (SVM) to detect cancer polyps in colonoscopy video, and a further analysis of their categories in the feature space using Self Organizing Maps (SOM). Our overall hypothesis is that the clinician's eye will be drawn to the salient features of the image and that sustained fixations will be associated with those features that are associated with disease states. |
Michael W von Grünau; Kamala Pilgrim; Rong Zhou Velocity discrimination thresholds for flowfield motions with moving observers Journal Article Vision Research, 47 (18), pp. 2453–2464, 2007. @article{Gruenau2007, title = {Velocity discrimination thresholds for flowfield motions with moving observers}, author = {Michael W von Grünau and Kamala Pilgrim and Rong Zhou}, doi = {10.1016/j.visres.2007.06.008}, year = {2007}, date = {2007-01-01}, journal = {Vision Research}, volume = {47}, number = {18}, pages = {2453--2464}, abstract = {The visual flow field, produced by forward locomotion, contains useful information about many aspects of visually guided behavior. But locomotion itself also contributes to possible distortions by adding head bobbing motions. Here we examine whether vertical head bobbing affects velocity discrimination thresholds and how the system may compensate for the distortions. Vertical head and eye movements while fixating were recorded during standing, walking or running on a treadmill. Bobbing noise was found to be larger during locomotion. The same observers were equally good at discriminating velocity increases in large accelerating flow fields when standing or walking or running. Simulated head bobbing was compensated when produced by pursuit eye movements, but not when it was part of the flow field. The results showed that these two contributions are additive and dealt with independently before they are combined. Distortions produced by body/head oscillations may also be compensated. Visual performance during running was at least as good as during walking, suggesting more efficient compensation mechanisms for running.}, keywords = {}, pubstate = {published}, tppubtype = {article} } The visual flow field, produced by forward locomotion, contains useful information about many aspects of visually guided behavior. But locomotion itself also contributes to possible distortions by adding head bobbing motions. Here we examine whether vertical head bobbing affects velocity discrimination thresholds and how the system may compensate for the distortions. Vertical head and eye movements while fixating were recorded during standing, walking or running on a treadmill. Bobbing noise was found to be larger during locomotion. The same observers were equally good at discriminating velocity increases in large accelerating flow fields when standing or walking or running. Simulated head bobbing was compensated when produced by pursuit eye movements, but not when it was part of the flow field. The results showed that these two contributions are additive and dealt with independently before they are combined. Distortions produced by body/head oscillations may also be compensated. Visual performance during running was at least as good as during walking, suggesting more efficient compensation mechanisms for running. |
Jyun Cheng Wang; Rong-Fuh Day The effects of attention inertia on advertisements on the WWW Journal Article Computers in Human Behavior, 23 (3), pp. 1390–1407, 2007. @article{Wang2007b, title = {The effects of attention inertia on advertisements on the WWW}, author = {Jyun Cheng Wang and Rong-Fuh Day}, doi = {10.1016/j.chb.2004.12.014}, year = {2007}, date = {2007-01-01}, journal = {Computers in Human Behavior}, volume = {23}, number = {3}, pages = {1390--1407}, abstract = {When a viewer browses a web site, one presumably performs the task of seeking information from a sequence of scattered web pages to form a meaningful path. The aim of this study is to explore changes in the distribution of attention to banner advertisements as a viewer advances along a meaningful path and their effects on the advertisements. With aid of an instrument called eye-tracker, a laboratory experiment was conducted to observe directly the attention that subjects allocate along meaningful paths. Our results show that at different levels of depth in a meaningful path, the amount of attention allocated to the content of a web page is not the same, regardless of whether attention indexes were based on dwell time or the number of fixations. Theoretically, this experiment successfully generalizes the attentional inertia theory to web environment and elaborates web advertising research by involving a significant web structural factor. In practice, this findings hint that web advertising located in the earlier and later phases of a path should be priced higher than advertising in the middle phases because, during these two phases, the audience is more sensitive to the peripheral advertising.}, keywords = {}, pubstate = {published}, tppubtype = {article} } When a viewer browses a web site, one presumably performs the task of seeking information from a sequence of scattered web pages to form a meaningful path. The aim of this study is to explore changes in the distribution of attention to banner advertisements as a viewer advances along a meaningful path and their effects on the advertisements. With aid of an instrument called eye-tracker, a laboratory experiment was conducted to observe directly the attention that subjects allocate along meaningful paths. Our results show that at different levels of depth in a meaningful path, the amount of attention allocated to the content of a web page is not the same, regardless of whether attention indexes were based on dwell time or the number of fixations. Theoretically, this experiment successfully generalizes the attentional inertia theory to web environment and elaborates web advertising research by involving a significant web structural factor. In practice, this findings hint that web advertising located in the earlier and later phases of a path should be priced higher than advertising in the middle phases because, during these two phases, the audience is more sensitive to the peripheral advertising. |
Yi Fang Tsai; Erik Viirre; Christopher Strychacz; Bradley Chase; Tzyy-Ping Jung Task performance and eye activity: Predicting behavior relating to cognitive workload Journal Article Aviation Space and Environmental Medicine, 78 (5), pp. B176–B185, 2007. @article{Tsai2007, title = {Task performance and eye activity: Predicting behavior relating to cognitive workload}, author = {Yi Fang Tsai and Erik Viirre and Christopher Strychacz and Bradley Chase and Tzyy-Ping Jung}, doi = {10.1017/S0007123416000144}, year = {2007}, date = {2007-01-01}, journal = {Aviation Space and Environmental Medicine}, volume = {78}, number = {5}, pages = {B176--B185}, abstract = {The focus of this study was to examine oculomotor behavioral changes while subjects performed auditory and driving tasks. There were 13 participants who completed 3 10-min tasks consisting of driving only, the Paced Auditory Serial Addition Task (PASAT) only, and a dual task of both driving and auditory tasks. For each participant, changes in six measures were assessed as a function of cognitive workload, specifically changes in eye activity, including blink frequency, blink duration, fixation frequency, fixation duration, pupil diameter, and horizontal vergence. In addition, deviations in lateral lane position were assessed as a measure of driving behavior. Compared with the subjects' behavior in the driving-only task, results showed an increase in blink frequency during the combined driving and auditory task. Also, during the dual task the mean pupil diameter and horizontal vergence increased when subjects performed well in the auditory task in contrast to when the subjects performed poorly. Evidence of visual tunneling or reduced range of scanning and decreases in rearview mirror and odometer glances appeared when subjects performed the driving and auditory dual task. There was no significant change in fixation frequency. However, decreased fixation duration appeared to predict upcoming errors in the auditory task. Pupil diameter changes were significantly higher when performing well on the auditory task than when subjects were performing poorly. Eye behavior trends reported in this study may provide insight to human behavior corresponding with cognitive workload, which may in turn be utilized to produce reliable workload indicators and applications that predict poor performance in real time.}, keywords = {}, pubstate = {published}, tppubtype = {article} } The focus of this study was to examine oculomotor behavioral changes while subjects performed auditory and driving tasks. There were 13 participants who completed 3 10-min tasks consisting of driving only, the Paced Auditory Serial Addition Task (PASAT) only, and a dual task of both driving and auditory tasks. For each participant, changes in six measures were assessed as a function of cognitive workload, specifically changes in eye activity, including blink frequency, blink duration, fixation frequency, fixation duration, pupil diameter, and horizontal vergence. In addition, deviations in lateral lane position were assessed as a measure of driving behavior. Compared with the subjects' behavior in the driving-only task, results showed an increase in blink frequency during the combined driving and auditory task. Also, during the dual task the mean pupil diameter and horizontal vergence increased when subjects performed well in the auditory task in contrast to when the subjects performed poorly. Evidence of visual tunneling or reduced range of scanning and decreases in rearview mirror and odometer glances appeared when subjects performed the driving and auditory dual task. There was no significant change in fixation frequency. However, decreased fixation duration appeared to predict upcoming errors in the auditory task. Pupil diameter changes were significantly higher when performing well on the auditory task than when subjects were performing poorly. Eye behavior trends reported in this study may provide insight to human behavior corresponding with cognitive workload, which may in turn be utilized to produce reliable workload indicators and applications that predict poor performance in real time. |
2006 |
Dimitris Agrafiotis; Nishan Canagarajah; David R Bull; Jim Kyle; Helen Seers; Matthew Dye A perceptually optimised video coding system for sign language communication at low bit rates Journal Article Signal Processing: Image Communication, 21 (7), pp. 531–549, 2006. @article{Agrafiotis2006, title = {A perceptually optimised video coding system for sign language communication at low bit rates}, author = {Dimitris Agrafiotis and Nishan Canagarajah and David R Bull and Jim Kyle and Helen Seers and Matthew Dye}, doi = {10.1016/j.image.2006.02.003}, year = {2006}, date = {2006-01-01}, journal = {Signal Processing: Image Communication}, volume = {21}, number = {7}, pages = {531--549}, abstract = {The ability to communicate remotely through the use of video as promised by wireless networks and already practised over fixed networks, is for deaf people as important as voice telephony is for hearing people. Sign languages are visual-spatial languages and as such demand good image quality for interaction and understanding. In this paper, we first analyse the sign language viewer's eye-gaze, based on the results of an eye-tracking study that we conducted, as well as the video content involved in sign language person-to-person communication. Based on this analysis we propose a sign language video coding system using foveated processing, which can lead to bit rate savings without compromising the comprehension of the coded sequence or equivalently produce a coded sequence with higher comprehension value at the same bit rate. We support this claim with the results of an initial comprehension assessment trial of such coded sequences by deaf users. The proposed system constitutes a new paradigm for coding sign language image sequences at limited bit rates. textcopyright 2006 Elsevier B.V. All rights reserved.}, keywords = {}, pubstate = {published}, tppubtype = {article} } The ability to communicate remotely through the use of video as promised by wireless networks and already practised over fixed networks, is for deaf people as important as voice telephony is for hearing people. Sign languages are visual-spatial languages and as such demand good image quality for interaction and understanding. In this paper, we first analyse the sign language viewer's eye-gaze, based on the results of an eye-tracking study that we conducted, as well as the video content involved in sign language person-to-person communication. Based on this analysis we propose a sign language video coding system using foveated processing, which can lead to bit rate savings without compromising the comprehension of the coded sequence or equivalently produce a coded sequence with higher comprehension value at the same bit rate. We support this claim with the results of an initial comprehension assessment trial of such coded sequences by deaf users. The proposed system constitutes a new paradigm for coding sign language image sequences at limited bit rates. textcopyright 2006 Elsevier B.V. All rights reserved. |
Denis Alamargot Eye and Pen: A new device for studying reading Journal Article Behavior Research Methods, 38 (2), pp. 287–299, 2006. @article{Alamargot2006, title = {Eye and Pen: A new device for studying reading}, author = {Denis Alamargot}, year = {2006}, date = {2006-01-01}, journal = {Behavior Research Methods}, volume = {38}, number = {2}, pages = {287--299}, abstract = {We present a new method for studying reading during writing and the relationships between these two activities. the Eye and Pen device makes a synchronous recording of handwriting and eye move- ments during written composition. it complements existing online methods by providing a fine-grained description of the visual information fixated during pauses as well as during the actual writing act. this device can contribute to the exploration of several research issues, since it can be used to investigate the role of the text produced so far and the documentary sources displayed in the task environment. the study of the engagement of reading during writing should provide important information about the dynamics of writing processes based on visual information. Written}, keywords = {}, pubstate = {published}, tppubtype = {article} } We present a new method for studying reading during writing and the relationships between these two activities. the Eye and Pen device makes a synchronous recording of handwriting and eye move- ments during written composition. it complements existing online methods by providing a fine-grained description of the visual information fixated during pauses as well as during the actual writing act. this device can contribute to the exploration of several research issues, since it can be used to investigate the role of the text produced so far and the documentary sources displayed in the task environment. the study of the engagement of reading during writing should provide important information about the dynamics of writing processes based on visual information. Written |
David Crundall; Editha M van Loon; Geoffrey Underwood Attraction and distraction of attention with roadside advertisements Journal Article Accident Analysis & Prevention, 38 (4), pp. 671–677, 2006. @article{Crundall2006, title = {Attraction and distraction of attention with roadside advertisements}, author = {David Crundall and Editha M van Loon and Geoffrey Underwood}, doi = {10.1016/j.aap.2005.12.012}, year = {2006}, date = {2006-01-01}, journal = {Accident Analysis & Prevention}, volume = {38}, number = {4}, pages = {671--677}, abstract = {The optimum positioning of roadside advertisements is recognized by the industry as an important factor in attracting the attention of passing drivers. Less acknowledged is the possibility that the location of an advertisement may distract attention from vital driving-related information. This study compared street-level advertisements (SLAs; predominantly bus shelters) with raised-level advertisements (RLAs) of the same size that were suspended 3 m above the ground, on their ability to attract attention under different task conditions. Participants were split into two groups and watched video clips of driving, rating them for hazardousness while their eye movements were recorded. One of the groups was additionally primed to attend to advertisements. SLAs received the most fixations when participants were solely looking for hazards, and the fewest fixations when primed to look for advertisements. Though SLAs also had longer fixations than the RLAs, they were more poorly recognized in a subsequent memory test. We conclude that SLAs attract and hold attention at inappropriate times compared to raised-level advertisements.}, keywords = {}, pubstate = {published}, tppubtype = {article} } The optimum positioning of roadside advertisements is recognized by the industry as an important factor in attracting the attention of passing drivers. Less acknowledged is the possibility that the location of an advertisement may distract attention from vital driving-related information. This study compared street-level advertisements (SLAs; predominantly bus shelters) with raised-level advertisements (RLAs) of the same size that were suspended 3 m above the ground, on their ability to attract attention under different task conditions. Participants were split into two groups and watched video clips of driving, rating them for hazardousness while their eye movements were recorded. One of the groups was additionally primed to attend to advertisements. SLAs received the most fixations when participants were solely looking for hazards, and the fewest fixations when primed to look for advertisements. Though SLAs also had longer fixations than the RLAs, they were more poorly recognized in a subsequent memory test. We conclude that SLAs attract and hold attention at inappropriate times compared to raised-level advertisements. |
Rong-Fuh Day; Gary C -W Shyi; Jyun Cheng Wang The effect of flash banners on multiattribute decision making: Distractor or source of arousal? Journal Article Psychology and Marketing, 23 (5), pp. 369–382, 2006. @article{Day2006, title = {The effect of flash banners on multiattribute decision making: Distractor or source of arousal?}, author = {Rong-Fuh Day and Gary C -W Shyi and Jyun Cheng Wang}, doi = {10.1002/mar}, year = {2006}, date = {2006-01-01}, journal = {Psychology and Marketing}, volume = {23}, number = {5}, pages = {369--382}, abstract = {The role of peripheral flash advertisements in decision making as a distractor or a source of arousal was examined. Participants were asked to perform multiattribute decision making in a display envi- ronment with or without banners of advertisement flashing occasion- ally in the peripheral region of the display. The flash banners acceler- ated the speed of decision making, although the participants rarely made eye movements in response to the banners or fixated their eyes on them. It was interesting to note that the participants' pupil sizes increased with the presence of flash banners. These findings suggest that rather than distracting participants' attention, flash banners appear to elevate the general level of arousal of the participants, which in turn led to making faster on-line decisions.}, keywords = {}, pubstate = {published}, tppubtype = {article} } The role of peripheral flash advertisements in decision making as a distractor or a source of arousal was examined. Participants were asked to perform multiattribute decision making in a display envi- ronment with or without banners of advertisement flashing occasion- ally in the peripheral region of the display. The flash banners acceler- ated the speed of decision making, although the participants rarely made eye movements in response to the banners or fixated their eyes on them. It was interesting to note that the participants' pupil sizes increased with the presence of flash banners. These findings suggest that rather than distracting participants' attention, flash banners appear to elevate the general level of arousal of the participants, which in turn led to making faster on-line decisions. |
Kristian Lukander A system for tracking gaze on handheld device Journal Article Behavior Research Methods, 38 (4), pp. 660–666, 2006. @article{Lukander2006, title = {A system for tracking gaze on handheld device}, author = {Kristian Lukander}, year = {2006}, date = {2006-01-01}, journal = {Behavior Research Methods}, volume = {38}, number = {4}, pages = {660--666}, abstract = {Many of the current gaze-tracking systems require that a subject's head be stabilized and that the interface be fixed to a table. This article describes a prototype system for tracking gaze on the screen of mobile, handheld devices. The proposed system frees the user and the interface from previous constraints, allowing natural freedom of movement within the operational envelope of the system. The method is software-based, and integrates a commercial eye-tracking device (EyeLink I) with a magnetic positional tracking device (Polhemus FASTRAK). The evaluation of the system shows that it is capable of producing valid data with adequate accuracy.}, keywords = {}, pubstate = {published}, tppubtype = {article} } Many of the current gaze-tracking systems require that a subject's head be stabilized and that the interface be fixed to a table. This article describes a prototype system for tracking gaze on the screen of mobile, handheld devices. The proposed system frees the user and the interface from previous constraints, allowing natural freedom of movement within the operational envelope of the system. The method is software-based, and integrates a commercial eye-tracking device (EyeLink I) with a magnetic positional tracking device (Polhemus FASTRAK). The evaluation of the system shows that it is capable of producing valid data with adequate accuracy. |
2005 |
Carol O'sullivan Collisions and attention Journal Article ACM Transactions on Applied Perception, 2 (3), pp. 309–321, 2005. @article{Osullivan2005, title = {Collisions and attention}, author = {Carol O'sullivan}, doi = {10.1145/1077399.1077407}, year = {2005}, date = {2005-01-01}, journal = {ACM Transactions on Applied Perception}, volume = {2}, number = {3}, pages = {309--321}, abstract = {Attention is an important factor in the perception of static and dynamic scenes, which should, therefore, be taken into account when creating graphical images and animation. Recently, researchers have recognized this fact and have been investigating how the focus of attention can be measured, predicted, and exploited in graphical systems. In this article, we explore some preliminary strategies for developing an automatic means of predicting and exploiting attention in the processing of collisions and other dynamic events. Recent work on the perception of causality has shown that attention can change the way in which a dynamic scene consisting of collision events is perceived. We describe a series of experiments designed to determine the source of biases in the perception of anomalous collision dynamics and, in particular, whether attention plays a role. Using an eyetracker, eye-movements were recorded while participants viewed animations of simple causal launching events in 3D involving two colliding spheres. Results indicated that there was indeed a definite pattern to the allocation of attention based on the nature of the event, which is promising for the goal of developing a predictive metric. As a follow-up, a paper-based experiment was carried out in which participants were asked to sketch the predicted post-collision trajectories of the same two spheres printed on paper. These experiments demonstrated that attention alone was not sufficient in determining performance, but rather the nature of the dynamic event itself also played a role.}, keywords = {}, pubstate = {published}, tppubtype = {article} } Attention is an important factor in the perception of static and dynamic scenes, which should, therefore, be taken into account when creating graphical images and animation. Recently, researchers have recognized this fact and have been investigating how the focus of attention can be measured, predicted, and exploited in graphical systems. In this article, we explore some preliminary strategies for developing an automatic means of predicting and exploiting attention in the processing of collisions and other dynamic events. Recent work on the perception of causality has shown that attention can change the way in which a dynamic scene consisting of collision events is perceived. We describe a series of experiments designed to determine the source of biases in the perception of anomalous collision dynamics and, in particular, whether attention plays a role. Using an eyetracker, eye-movements were recorded while participants viewed animations of simple causal launching events in 3D involving two colliding spheres. Results indicated that there was indeed a definite pattern to the allocation of attention based on the nature of the event, which is promising for the goal of developing a predictive metric. As a follow-up, a paper-based experiment was carried out in which participants were asked to sketch the predicted post-collision trajectories of the same two spheres printed on paper. These experiments demonstrated that attention alone was not sufficient in determining performance, but rather the nature of the dynamic event itself also played a role. |
Peter Tarasewich; Marc Pomplun; Stephanie Fillion; Daniel Broberg The enhanced restricted focus viewer Journal Article International Journal of Human-Computer Interaction, 19 (1), pp. 35–54, 2005. @article{Tarasewich2005, title = {The enhanced restricted focus viewer}, author = {Peter Tarasewich and Marc Pomplun and Stephanie Fillion and Daniel Broberg}, doi = {10.1207/s15327590ijhc1901_4}, year = {2005}, date = {2005-01-01}, journal = {International Journal of Human-Computer Interaction}, volume = {19}, number = {1}, pages = {35--54}, abstract = {The Enhanced Restricted Focus Viewer (ERFV) is a unique software tool for tracking the visual attention of users in hyperlinked environments, such as Web sites. The software collects data, such as mouse clicks along with the path of users' visual attention, as they browse a site. Unlike traditional eye-tracking procedures, the ERFV requires no hardware to operate other than a personal computer. In addition to time and cost savings, the ERFV allows the administration of usability testing to groups of participants simultaneously. A laboratory test comparing the ERFV to a hardware-based eye-tracking system showed that the two methods compared favorably in terms of how well they track a user's visual attention. The value of the ERFV as a usability testing tool was demonstrated through an experiment that evaluated two Web sites that were equivalent in content but that differed in terms of design. Although several open issues concerning the ERFV still remain, some of these issues are being addressed through ongoing research efforts.}, keywords = {}, pubstate = {published}, tppubtype = {article} } The Enhanced Restricted Focus Viewer (ERFV) is a unique software tool for tracking the visual attention of users in hyperlinked environments, such as Web sites. The software collects data, such as mouse clicks along with the path of users' visual attention, as they browse a site. Unlike traditional eye-tracking procedures, the ERFV requires no hardware to operate other than a personal computer. In addition to time and cost savings, the ERFV allows the administration of usability testing to groups of participants simultaneously. A laboratory test comparing the ERFV to a hardware-based eye-tracking system showed that the two methods compared favorably in terms of how well they track a user's visual attention. The value of the ERFV as a usability testing tool was demonstrated through an experiment that evaluated two Web sites that were equivalent in content but that differed in terms of design. Although several open issues concerning the ERFV still remain, some of these issues are being addressed through ongoing research efforts. |
David Crundall; Peter Chapman; Emma France; Geoffrey Underwood; Nicola Phelps What attracts attention during police pursuit driving? Journal Article Applied Cognitive Psychology, 19 (4), pp. 409–420, 2005. @article{Crundall2005, title = {What attracts attention during police pursuit driving?}, author = {David Crundall and Peter Chapman and Emma France and Geoffrey Underwood and Nicola Phelps}, doi = {10.1002/acp.1067}, year = {2005}, date = {2005-01-01}, journal = {Applied Cognitive Psychology}, volume = {19}, number = {4}, pages = {409--420}, abstract = {Efficient deployment of attention is important to the safe execution of tasks with a high content of visual information, such as driving. Chasing a lead vehicle is an extremely demanding and dangerous task, though little is known of the visual skills required. A study is reported that recorded the eye movements of police drivers and two control groups (novices and age- and experienced- matched controls) while watching a series of video clips of driving. The clips included pursuits, emergency response drives, and control drives (at normal speeds) around Nottinghamshire, UK. Analysis of gaze durations within certain categories of stimuli revealed that daytime pursuit drives correspond with an increase in gaze durations on a lead car (controlled for exposure), though police drivers direct their attention to other sources of potential hazards, such as pedestrians, more so than other drivers.}, keywords = {}, pubstate = {published}, tppubtype = {article} } Efficient deployment of attention is important to the safe execution of tasks with a high content of visual information, such as driving. Chasing a lead vehicle is an extremely demanding and dangerous task, though little is known of the visual skills required. A study is reported that recorded the eye movements of police drivers and two control groups (novices and age- and experienced- matched controls) while watching a series of video clips of driving. The clips included pursuits, emergency response drives, and control drives (at normal speeds) around Nottinghamshire, UK. Analysis of gaze durations within certain categories of stimuli revealed that daytime pursuit drives correspond with an increase in gaze durations on a lead car (controlled for exposure), though police drivers direct their attention to other sources of potential hazards, such as pedestrians, more so than other drivers. |
2004 |
David Crundall; Claire Shenton; Geoffrey Underwood Eye movements during intentional car following Journal Article Perception, 33 (8), pp. 975–986, 2004. @article{Crundall2004, title = {Eye movements during intentional car following}, author = {David Crundall and Claire Shenton and Geoffrey Underwood}, doi = {10.1068/p5105}, year = {2004}, date = {2004-01-01}, journal = {Perception}, volume = {33}, number = {8}, pages = {975--986}, abstract = {Does intentional car following capture visual attention to the extent that driving may be impaired? We tested fifteen participants on a rudimentary driving simulator. Participants were either instructed to follow a vehicle ahead through a simulated version of London, or were given verbal instructions on where to turn during the route. The presence or absence of pedestrians, and the simulated time of the drive (day or night) were varied across the trials. Eye movements were recorded along with behavioural measures including give-way violations, give-way accidents, and kerb impacts. The results revealed that intentional car following reduced the spread of search and increased fixation durations, with a dramatic increase in the time spent processing the vehicle ahead (controlled for exposure). The effects were most pronounced during nighttime drives. During the car-following trials participants were also less aware of pedestrians, produced more give-way violations, and were involved in more give-way accidents. The results draw attention to the problems encountered during car following, and we relate this to the cognitive demands placed on drivers, especially police drivers who often engage in intentional car following and pursuits.}, keywords = {}, pubstate = {published}, tppubtype = {article} } Does intentional car following capture visual attention to the extent that driving may be impaired? We tested fifteen participants on a rudimentary driving simulator. Participants were either instructed to follow a vehicle ahead through a simulated version of London, or were given verbal instructions on where to turn during the route. The presence or absence of pedestrians, and the simulated time of the drive (day or night) were varied across the trials. Eye movements were recorded along with behavioural measures including give-way violations, give-way accidents, and kerb impacts. The results revealed that intentional car following reduced the spread of search and increased fixation durations, with a dramatic increase in the time spent processing the vehicle ahead (controlled for exposure). The effects were most pronounced during nighttime drives. During the car-following trials participants were also less aware of pedestrians, produced more give-way violations, and were involved in more give-way accidents. The results draw attention to the problems encountered during car following, and we relate this to the cognitive demands placed on drivers, especially police drivers who often engage in intentional car following and pursuits. |
Christof Körner Sequential Processing in Comprehension of Hierarchical Graphs Journal Article Applied Cognitive Psychology, 18 , pp. 467–480, 2004. @article{Koerner2004, title = {Sequential Processing in Comprehension of Hierarchical Graphs}, author = {Christof Körner}, doi = {10.1002/acp.997}, year = {2004}, date = {2004-01-01}, journal = {Applied Cognitive Psychology}, volume = {18}, pages = {467--480}, abstract = {Hierarchical graphs represent the relationships between non-numerical entities or concepts (like computer file systems, family trees, etc). Graph nodes represent the concepts and interconnecting lines represent the relationships. We recorded participants' eye movements while viewing such graphs to test two possible models of graph comprehension. Graph readers had to answer interpretive questions, which required comparisons between two graph nodes. One model postulates a search and a combined search-reasoning stage of graph comprehension (two-stage model), whereas the second model predicts three stages, two stages devoted to the search of the relevant graph nodes and a separate reasoning stage. A detailed analysis of the eye movement data provided clear support for the three-stage model. This is in line with recent studies, which suggest that participants serialize problem solving tasks in order to minimize the overall processing load.}, keywords = {}, pubstate = {published}, tppubtype = {article} } Hierarchical graphs represent the relationships between non-numerical entities or concepts (like computer file systems, family trees, etc). Graph nodes represent the concepts and interconnecting lines represent the relationships. We recorded participants' eye movements while viewing such graphs to test two possible models of graph comprehension. Graph readers had to answer interpretive questions, which required comparisons between two graph nodes. One model postulates a search and a combined search-reasoning stage of graph comprehension (two-stage model), whereas the second model predicts three stages, two stages devoted to the search of the relevant graph nodes and a separate reasoning stage. A detailed analysis of the eye movement data provided clear support for the three-stage model. This is in line with recent studies, which suggest that participants serialize problem solving tasks in order to minimize the overall processing load. |
Jason S McCarley; Arthur F Kramer; Christopher D Wickens; Eric D Vidoni; Walter R Boot Visual skills in airport security inspection Journal Article Psychological Science, 15 (5), pp. 302–306, 2004. @article{McCarley2004, title = {Visual skills in airport security inspection}, author = {Jason S McCarley and Arthur F Kramer and Christopher D Wickens and Eric D Vidoni and Walter R Boot}, doi = {10.1111/j.0956-7976.2004.00673.x}, year = {2004}, date = {2004-01-01}, journal = {Psychological Science}, volume = {15}, number = {5}, pages = {302--306}, abstract = {An experiment examined visual performance in a simulated luggage-screening task. Observers participated in five sessions of a task requiring them to search for knives hidden in x-ray images of cluttered bags. Sensitivity and response times improved reliably as a result of practice. Eye movement data revealed that sensitivity increases were produced entirely by changes in observers' ability to recognize target objects, and not by changes in the effectiveness of visual scanning. Moreover, recognition skills were in part stimulus-specific, such that performance was degraded by the introduction of unfamiliar target objects. Implications for screener training are discussed.}, keywords = {}, pubstate = {published}, tppubtype = {article} } An experiment examined visual performance in a simulated luggage-screening task. Observers participated in five sessions of a task requiring them to search for knives hidden in x-ray images of cluttered bags. Sensitivity and response times improved reliably as a result of practice. Eye movement data revealed that sensitivity increases were produced entirely by changes in observers' ability to recognize target objects, and not by changes in the effectiveness of visual scanning. Moreover, recognition skills were in part stimulus-specific, such that performance was degraded by the introduction of unfamiliar target objects. Implications for screener training are discussed. |
2003 |
Tomas Lindberg; Risto Näsänen The effect of icon spacing and size on the speed of icon processing in the human visual system Journal Article Displays, 24 (3), pp. 111–120, 2003. @article{Lindberg2003, title = {The effect of icon spacing and size on the speed of icon processing in the human visual system}, author = {Tomas Lindberg and Risto Näsänen}, doi = {10.1016/S0141-9382(03)00035-0}, year = {2003}, date = {2003-01-01}, journal = {Displays}, volume = {24}, number = {3}, pages = {111--120}, abstract = {Alphanumeric and graphical information needs to be presented in such a way that its perception is accurate, fast and as effortless as possible. This study investigated the effects of spacing and size of individual interface elements on their perception. Experiment 1 investigated the effect of icon spacing on the speed of visual search for a target icon and determined the perceptual span for icons, that is, the number of icons that can be processed by one eye fixation. Experiment 2 studied the effect of size, and experiment 3 the subjective preferences for levels of icon spacing. The results of experiment 1 showed that spacing does not have an effect on search times. On average the perceptual span for icons was found to be 25 arranged in a 5 × 5 array. The size of the interface elements, on the other hand, was found to have a great effect. Icons smaller than 0.7° resulted in significantly raised search times. Experiment 3 revealed that an inter-element spacing of one icon is to be preferred and a spacing of zero icons is to be avoided.}, keywords = {}, pubstate = {published}, tppubtype = {article} } Alphanumeric and graphical information needs to be presented in such a way that its perception is accurate, fast and as effortless as possible. This study investigated the effects of spacing and size of individual interface elements on their perception. Experiment 1 investigated the effect of icon spacing on the speed of visual search for a target icon and determined the perceptual span for icons, that is, the number of icons that can be processed by one eye fixation. Experiment 2 studied the effect of size, and experiment 3 the subjective preferences for levels of icon spacing. The results of experiment 1 showed that spacing does not have an effect on search times. On average the perceptual span for icons was found to be 25 arranged in a 5 × 5 array. The size of the interface elements, on the other hand, was found to have a great effect. Icons smaller than 0.7° resulted in significantly raised search times. Experiment 3 revealed that an inter-element spacing of one icon is to be preferred and a spacing of zero icons is to be avoided. |
Risto Näsänen; Helena Ojanpää Effect of image contrast and sharpness on visual search for computer icons Journal Article Displays, 24 , pp. 137–144, 2003. @article{Naesaenen2003, title = {Effect of image contrast and sharpness on visual search for computer icons}, author = {Risto Näsänen and Helena Ojanpää}, doi = {10.1016/j.displa.2003.09.003}, year = {2003}, date = {2003-01-01}, journal = {Displays}, volume = {24}, pages = {137--144}, abstract = {The purpose of the study was to determine the effect of image blur and contrast on the speed of visual search for user interface icons and investigate how the effect is reflected in eye movement parameters. The task of the observer was to search for a target icon from among a rectangular array of distracter icons. A staircase algorithm was used to determine the stimulus presentation time, threshold search time, for which the probability of correct responses was 0.79. Simultaneously, eye-movements were recorded with a video eye-tracker with a sampling rate of 250 Hz. Image sharpness was varied by filtering the stimulus images with a Gaussian low-pass filter. The results showed that with increasing contrast or sharpness search time, number of fixations per search, and fixation duration first decreased, and then became constant at medium levels of contrast or sharpness. These effects were somewhat more pronounced for contrast than for sharpness. Saccade amplitudes were not affected by contrast or sharpness. The results suggest that the perception of user interface icons is quite resistant to small or moderate deterioration of image quality.}, keywords = {}, pubstate = {published}, tppubtype = {article} } The purpose of the study was to determine the effect of image blur and contrast on the speed of visual search for user interface icons and investigate how the effect is reflected in eye movement parameters. The task of the observer was to search for a target icon from among a rectangular array of distracter icons. A staircase algorithm was used to determine the stimulus presentation time, threshold search time, for which the probability of correct responses was 0.79. Simultaneously, eye-movements were recorded with a video eye-tracker with a sampling rate of 250 Hz. Image sharpness was varied by filtering the stimulus images with a Gaussian low-pass filter. The results showed that with increasing contrast or sharpness search time, number of fixations per search, and fixation duration first decreased, and then became constant at medium levels of contrast or sharpness. These effects were somewhat more pronounced for contrast than for sharpness. Saccade amplitudes were not affected by contrast or sharpness. The results suggest that the perception of user interface icons is quite resistant to small or moderate deterioration of image quality. |
Helena Ojanpää; Risto Näsänen Effects of luminance and colour contrast on the search of information on display devices Journal Article Displays, 24 (4-5), pp. 167–178, 2003. @article{Ojanpaeae2003a, title = {Effects of luminance and colour contrast on the search of information on display devices}, author = {Helena Ojanpää and Risto Näsänen}, doi = {10.1016/j.displa.2004.01.003}, year = {2003}, date = {2003-01-01}, journal = {Displays}, volume = {24}, number = {4-5}, pages = {167--178}, abstract = {For black-and-white alphanumeric information, the speed of visual perception decreases with decreasing contrast. We investigated the effect of luminance contrast on the speed of visual search and reading when characters and background differed also with respect to colour. The luminance contrast between background and characters was varied, while colour contrast was held nearly constant. Stimuli with moderate (green/grey) or high colour contrast (green/red or yellow/blue), and three character sizes (0.17, 0.37, and 1.26deg) were used. Eye movements were recorded during the visual search task. We found that the visual search times, number of eye fixations, and mean fixation durations increased strongly with decreasing luminance contrast despite the presence of colour contrast. The effects were largest for small characters (0.17deg), but occurred also for medium (0.37deg), and in some cases for large (1.26deg) characters. Similarly, reading rates decreased with decreasing luminance contrast. Thus, moderate or even high colour contrast does not guarantee quick visual perception, if the luminance contrast between characters and background is small. This is probably due to the fact that visual acuity (the ability to see small details) is considerably lower for pure colour information than for luminance information. Therefore, in user interfaces, good visibility of alphanumeric information requires clear luminance (brightness) difference between foreground and background.}, keywords = {}, pubstate = {published}, tppubtype = {article} } For black-and-white alphanumeric information, the speed of visual perception decreases with decreasing contrast. We investigated the effect of luminance contrast on the speed of visual search and reading when characters and background differed also with respect to colour. The luminance contrast between background and characters was varied, while colour contrast was held nearly constant. Stimuli with moderate (green/grey) or high colour contrast (green/red or yellow/blue), and three character sizes (0.17, 0.37, and 1.26deg) were used. Eye movements were recorded during the visual search task. We found that the visual search times, number of eye fixations, and mean fixation durations increased strongly with decreasing luminance contrast despite the presence of colour contrast. The effects were largest for small characters (0.17deg), but occurred also for medium (0.37deg), and in some cases for large (1.26deg) characters. Similarly, reading rates decreased with decreasing luminance contrast. Thus, moderate or even high colour contrast does not guarantee quick visual perception, if the luminance contrast between characters and background is small. This is probably due to the fact that visual acuity (the ability to see small details) is considerably lower for pure colour information than for luminance information. Therefore, in user interfaces, good visibility of alphanumeric information requires clear luminance (brightness) difference between foreground and background. |
Dimitris Agrafiotis; Nishan Canagarajah; David R Bull; Matthew Dye Perceptually optimised sign language video coding based on eye tracking analysis Journal Article Electronics Letters, 39 , pp. 1–2, 2003. @article{Agrafiotis2003, title = {Perceptually optimised sign language video coding based on eye tracking analysis}, author = {Dimitris Agrafiotis and Nishan Canagarajah and David R Bull and Matthew Dye}, doi = {10.1049/el}, year = {2003}, date = {2003-01-01}, journal = {Electronics Letters}, volume = {39}, pages = {1--2}, abstract = {A perceptually optimised approach to sign language video coding is presented. The proposed approach is based on the results (included) of an eye tracking study in the visual attention of sign language viewers. Results show reductions in bit rate of over 30% with very good subjective quality.}, keywords = {}, pubstate = {published}, tppubtype = {article} } A perceptually optimised approach to sign language video coding is presented. The proposed approach is based on the results (included) of an eye tracking study in the visual attention of sign language viewers. Results show reductions in bit rate of over 30% with very good subjective quality. |
David Crundall; Peter Chapman; Nicola Phelps; Geoffrey Underwood Eye movements and hazard perception in police pursuit and emergency response driving Journal Article Journal of Experimental Psychology: Applied, 9 (3), pp. 163–174, 2003. @article{Crundall2003, title = {Eye movements and hazard perception in police pursuit and emergency response driving}, author = {David Crundall and Peter Chapman and Nicola Phelps and Geoffrey Underwood}, doi = {10.1037/1076-898X.9.3.163}, year = {2003}, date = {2003-01-01}, journal = {Journal of Experimental Psychology: Applied}, volume = {9}, number = {3}, pages = {163--174}, abstract = {How do police cope with the visual demands placed on them during pursuit driving? This study compared the hazard ratings, eye movements, and physiological responses of police drivers with novice and with age-matched control drivers while viewing video clips of driving taken from police vehicles. The clips included pursuits, emergency responses, and control drives. Although police drivers did not report more hazards than the other participants reported, they had an increased frequency of electrodermal responses while viewing dangerous clips and a greater visual sampling rate and spread of search. However, despite an overall police advantage in oculomotor and physiological measures, all drivers had a reduced spread of search in nighttime pursuits because of the focusing of overt attention.}, keywords = {}, pubstate = {published}, tppubtype = {article} } How do police cope with the visual demands placed on them during pursuit driving? This study compared the hazard ratings, eye movements, and physiological responses of police drivers with novice and with age-matched control drivers while viewing video clips of driving taken from police vehicles. The clips included pursuits, emergency responses, and control drives. Although police drivers did not report more hazards than the other participants reported, they had an increased frequency of electrodermal responses while viewing dangerous clips and a greater visual sampling rate and spread of search. However, despite an overall police advantage in oculomotor and physiological measures, all drivers had a reduced spread of search in nighttime pursuits because of the focusing of overt attention. |
Elizabeth Gilman; Geoffrey Underwood Restricting the field of view to investigate the perceptual spans of pianists Journal Article Visual Cognition, 10 (2), pp. 201–232, 2003. @article{Gilman2003, title = {Restricting the field of view to investigate the perceptual spans of pianists}, author = {Elizabeth Gilman and Geoffrey Underwood}, doi = {10.1080/13506280244000104}, year = {2003}, date = {2003-01-01}, journal = {Visual Cognition}, volume = {10}, number = {2}, pages = {201--232}, abstract = {An experiment is reported, which was designed to determine how the perceptual span of pianists varies with developing skill and cognitive load. Eye-movements were recorded as musical phrases were presented through a gaze-contingent window, which contained one beat, two beats, or four beats. In a control condition, the music was presented without a window. The pianists were required to perform three tasks of varying cognitive load: An error-detection task (low load); a sight- reading task (medium load); and a transposition task (high load). Measures taken comprised fixation duration, fixation frequency, saccade length, fixation locations, performance duration, note duration, position of first error, number of errors, and eye±hand span. The results indicate that good and poor sight-readers do not differ in terms of perceptual span. However, good sight-readers were found to have larger eye±hand spans. Furthermore, the results show that increasing cognitive load decreases eye±hand span, but has little effect on perceptual span.}, keywords = {}, pubstate = {published}, tppubtype = {article} } An experiment is reported, which was designed to determine how the perceptual span of pianists varies with developing skill and cognitive load. Eye-movements were recorded as musical phrases were presented through a gaze-contingent window, which contained one beat, two beats, or four beats. In a control condition, the music was presented without a window. The pianists were required to perform three tasks of varying cognitive load: An error-detection task (low load); a sight- reading task (medium load); and a transposition task (high load). Measures taken comprised fixation duration, fixation frequency, saccade length, fixation locations, performance duration, note duration, position of first error, number of errors, and eye±hand span. The results indicate that good and poor sight-readers do not differ in terms of perceptual span. However, good sight-readers were found to have larger eye±hand spans. Furthermore, the results show that increasing cognitive load decreases eye±hand span, but has little effect on perceptual span. |
2002 |
Tanja R M Coeckelbergh The effect of visual field defects on driving performance Journal Article Archives of Ophthalmology, 120 (11), pp. 1509–1516, 2002. @article{Coeckelbergh2002a, title = {The effect of visual field defects on driving performance}, author = {Tanja R M Coeckelbergh}, doi = {10.1001/archopht.120.11.1509}, year = {2002}, date = {2002-01-01}, journal = {Archives of Ophthalmology}, volume = {120}, number = {11}, pages = {1509--1516}, abstract = {Objectives: To investigate the effect of visual field de-fects on driving performance, and to predict practical fit-ness to drive. Methods: The driving performance of 87 subjects with visual field defects due to ocular abnormalities was as-sessed on a driving simulator and during an on-road driv-ing test. Outcome Measures: The final score on the on-road driving test and simulator indexes, such as driving speed, viewing behavior, lateral position, time-headway, and time to collision. Results: Subjects with visual field defects showed dif-ferential performance on measures of driving speed, steer-ing stability, lateral position, time to collision, and time-headway. Effective compensation consisted of reduced driving speed in cases of central visual field defects and increased scanning in cases of peripheral visual field de-fects. The sensitivity and specificity of models based on vision, visual attention, and compensatory viewing effi-ciency were increased when the distance at which the sub-ject started to scan was taken into account. Conclusions: Subjects with visual field defects demon-strated differential performance on several driving simu-lator indexes. Driving examiners considered reduced speed and increased scanning to be valid compensation for cen-tral and peripheral visual field defects, respectively. Pre-dicting practical fitness to drive was improved by taking driving simulator indexes into account.}, keywords = {}, pubstate = {published}, tppubtype = {article} } Objectives: To investigate the effect of visual field de-fects on driving performance, and to predict practical fit-ness to drive. Methods: The driving performance of 87 subjects with visual field defects due to ocular abnormalities was as-sessed on a driving simulator and during an on-road driv-ing test. Outcome Measures: The final score on the on-road driving test and simulator indexes, such as driving speed, viewing behavior, lateral position, time-headway, and time to collision. Results: Subjects with visual field defects showed dif-ferential performance on measures of driving speed, steer-ing stability, lateral position, time to collision, and time-headway. Effective compensation consisted of reduced driving speed in cases of central visual field defects and increased scanning in cases of peripheral visual field de-fects. The sensitivity and specificity of models based on vision, visual attention, and compensatory viewing effi-ciency were increased when the distance at which the sub-ject started to scan was taken into account. Conclusions: Subjects with visual field defects demon-strated differential performance on several driving simu-lator indexes. Driving examiners considered reduced speed and increased scanning to be valid compensation for cen-tral and peripheral visual field defects, respectively. Pre-dicting practical fitness to drive was improved by taking driving simulator indexes into account. |
Tanja R M Coeckelbergh; Frans W Cornelissen; Wiebo H Brouwer; Aart C Kooijman The effect of visual field defects on eye movements and practical fitness to drive Journal Article Vision Research, 42 (5), pp. 669–677, 2002. @article{Coeckelbergh2002b, title = {The effect of visual field defects on eye movements and practical fitness to drive}, author = {Tanja R M Coeckelbergh and Frans W Cornelissen and Wiebo H Brouwer and Aart C Kooijman}, doi = {10.1016/S0042-6989(01)00297-8}, year = {2002}, date = {2002-01-01}, journal = {Vision Research}, volume = {42}, number = {5}, pages = {669--677}, abstract = {Eye movements of subjects with visual field defects due to ocular pathology were monitored while performing a dot counting task and a visual search task. Subjects with peripheral field defects required more fixations, longer search times, made more errors, and had shorter fixation durations than control subjects. Subjects with central field defects performed less well than control subjects although no specific impairment could be pinpointed. In both groups a monotonous relationship was observed between the visual field impairment and eye movement parameters. The use of eye movement parameters to predict viewing behavior in a complex task (e.g. driving) was limited.}, keywords = {}, pubstate = {published}, tppubtype = {article} } Eye movements of subjects with visual field defects due to ocular pathology were monitored while performing a dot counting task and a visual search task. Subjects with peripheral field defects required more fixations, longer search times, made more errors, and had shorter fixation durations than control subjects. Subjects with central field defects performed less well than control subjects although no specific impairment could be pinpointed. In both groups a monotonous relationship was observed between the visual field impairment and eye movement parameters. The use of eye movement parameters to predict viewing behavior in a complex task (e.g. driving) was limited. |
Boris M Velichkovsky; Sascha M Dornhoefer; Mathias Kopf; Jens R Helmert; Markus Joos Change detection and occlusion modes in road-traffic scenarios Journal Article Transportation Research Part F: Traffic Psychology and Behaviour, 5 (2), pp. 99–109, 2002. @article{Velichkovsky2002, title = {Change detection and occlusion modes in road-traffic scenarios}, author = {Boris M Velichkovsky and Sascha M Dornhoefer and Mathias Kopf and Jens R Helmert and Markus Joos}, doi = {10.1016/S1369-8478(02)00009-8}, year = {2002}, date = {2002-01-01}, journal = {Transportation Research Part F: Traffic Psychology and Behaviour}, volume = {5}, number = {2}, pages = {99--109}, abstract = {Change blindness phenomena are widely known in cognitive science, but their relation to driving is not quite clear. We report a study where subjects viewed colour video stills of natural traffic while eye movements were recorded. A change could occur randomly in three different occlusion modes-blinks, blanks and saccades-or during a fixation (as control condition). These changes could be either relevant or irrelevant with respect to the traffic safety. We used deletions as well as insertions of objects. All occlusion modes were equivalent concerning detection rate and reaction time, deviating from the control condition only. The detection of relevant changes was both more likely and faster than that of irrelevant ones, particularly for relevant insertions, which approached the base line level. Even in this case, it took about 180 ms longer to react to changes when they occurred during a saccade, blink or blank. In a second study, relevant insertions and the blank occlusion were used in a driving simulator environment. We found a surprising effect in the dynamic setting: an advantage in change detection rate and time with blanks compared to the control condition. Change detection was also good during blinks, but not in saccades. Possible explanation of these effects and their practical implications are discussed.}, keywords = {}, pubstate = {published}, tppubtype = {article} } Change blindness phenomena are widely known in cognitive science, but their relation to driving is not quite clear. We report a study where subjects viewed colour video stills of natural traffic while eye movements were recorded. A change could occur randomly in three different occlusion modes-blinks, blanks and saccades-or during a fixation (as control condition). These changes could be either relevant or irrelevant with respect to the traffic safety. We used deletions as well as insertions of objects. All occlusion modes were equivalent concerning detection rate and reaction time, deviating from the control condition only. The detection of relevant changes was both more likely and faster than that of irrelevant ones, particularly for relevant insertions, which approached the base line level. Even in this case, it took about 180 ms longer to react to changes when they occurred during a saccade, blink or blank. In a second study, relevant insertions and the blank occlusion were used in a driving simulator environment. We found a surprising effect in the dynamic setting: an advantage in change detection rate and time with blanks compared to the control condition. Change detection was also good during blinks, but not in saccades. Possible explanation of these effects and their practical implications are discussed. |
2001 |
Risto Näsänen; Jan Karlsson; Helena Ojanpää Display quality and the speed of visual letter search Journal Article Displays, 22 (4), pp. 107–113, 2001. @article{Naesaenen2001, title = {Display quality and the speed of visual letter search}, author = {Risto Näsänen and Jan Karlsson and Helena Ojanpää}, doi = {10.1016/S0141-9382(01)00058-0}, year = {2001}, date = {2001-01-01}, journal = {Displays}, volume = {22}, number = {4}, pages = {107--113}, abstract = {Previously it has been suggested that visual search tasks can be used to evaluate the perceptual quality of display devices with respect to their ability to convey alphanumeric information. The purpose of the present study was to examine how character size and contrast used in a visual search test affects its sensitivity to differences in the quality of display devices. The task of the observer was to search for, and identify, an uppercase letter from a rectangular array of characters in which the other items were numerals. Threshold search time, that is, the duration of stimulus presentation required for search that is successful with a given probability, was determined by using a multiple-alternative staircase method. Eye movements were recorded simultaneously by using a fast video eye tracker. Threshold search times were measured as a function of character size at two contrast levels using a CRT and an LCD display. For all experimental conditions, threshold search time decreased with increasing letter size. This was accompanied with a decrease in the number of eye fixations per search as well as a decrease of fixation duration. At high contrast (CMichelson≈ 1), no statistically significant difference was found between the two displays. However, at the lower contrast used (CMichelson≈ 0.2) and at small character sizes, threshold search times for the CRT display were clearly longer and the number of fixations per search was higher than for the LCD display. In conclusion, visual letter search is a more sensitive method for display evaluation at small contrasts and with small character sizes.}, keywords = {}, pubstate = {published}, tppubtype = {article} } Previously it has been suggested that visual search tasks can be used to evaluate the perceptual quality of display devices with respect to their ability to convey alphanumeric information. The purpose of the present study was to examine how character size and contrast used in a visual search test affects its sensitivity to differences in the quality of display devices. The task of the observer was to search for, and identify, an uppercase letter from a rectangular array of characters in which the other items were numerals. Threshold search time, that is, the duration of stimulus presentation required for search that is successful with a given probability, was determined by using a multiple-alternative staircase method. Eye movements were recorded simultaneously by using a fast video eye tracker. Threshold search times were measured as a function of character size at two contrast levels using a CRT and an LCD display. For all experimental conditions, threshold search time decreased with increasing letter size. This was accompanied with a decrease in the number of eye fixations per search as well as a decrease of fixation duration. At high contrast (CMichelson≈ 1), no statistically significant difference was found between the two displays. However, at the lower contrast used (CMichelson≈ 0.2) and at small character sizes, threshold search times for the CRT display were clearly longer and the number of fixations per search was higher than for the LCD display. In conclusion, visual letter search is a more sensitive method for display evaluation at small contrasts and with small character sizes. |
Risto Näsänen; Helena Ojanpää; Ilpo Kojo Effect of stimulus contrast on performance and eye movements in visual search Journal Article Vision Research, 41 (14), pp. 1817–1824, 2001. @article{Naesaenen2001a, title = {Effect of stimulus contrast on performance and eye movements in visual search}, author = {Risto Näsänen and Helena Ojanpää and Ilpo Kojo}, doi = {10.1016/S0042-6989(01)00056-6}, year = {2001}, date = {2001-01-01}, journal = {Vision Research}, volume = {41}, number = {14}, pages = {1817--1824}, abstract = {According to the visual span control hypothesis, eye movements are controlled in relation to the size of visual span. In reading, the decrease of contrast reduces visual span, saccade sizes, and reading speed. The purpose of the present study is to determine how stimulus contrast affects the speed of two-dimensional visual search and how changes in eye movements and visual span could explain changes in performance. The task of the observer was to search for, and identify, an uppercase letter from a rectangular array of characters in which the other items were numerals. Threshold search time, i.e. the duration of stimulus presentation required for search that is successful with a given probability, was determined by using a multiple-alternative staircase method. Eye movements were recorded simultaneously by using a video eye tracker. Four different set sizes (the sizes of stimulus array) (3 × 3-10 × 10), and five different contrasts (0.0186 - 0.412) were used. At all set sizes, threshold search time decreased with increasing contrast. Also the average number of fixations per search decreased with increasing contrast. At the smallest set size (3 × 3), only one fixation was needed except at the lowest contrast. Average fixation duration decreased and saccade amplitudes increased slightly with increasing contrast. The reduction of the number of fixations with increasing contrast suggests that visual span, i.e. the area from which information can be collected at one fixation, increases with increasing contrast. The reduction of the number of fixations together with reduced fixation duration result in reduced search times when contrast increases.}, keywords = {}, pubstate = {published}, tppubtype = {article} } According to the visual span control hypothesis, eye movements are controlled in relation to the size of visual span. In reading, the decrease of contrast reduces visual span, saccade sizes, and reading speed. The purpose of the present study is to determine how stimulus contrast affects the speed of two-dimensional visual search and how changes in eye movements and visual span could explain changes in performance. The task of the observer was to search for, and identify, an uppercase letter from a rectangular array of characters in which the other items were numerals. Threshold search time, i.e. the duration of stimulus presentation required for search that is successful with a given probability, was determined by using a multiple-alternative staircase method. Eye movements were recorded simultaneously by using a video eye tracker. Four different set sizes (the sizes of stimulus array) (3 × 3-10 × 10), and five different contrasts (0.0186 - 0.412) were used. At all set sizes, threshold search time decreased with increasing contrast. Also the average number of fixations per search decreased with increasing contrast. At the smallest set size (3 × 3), only one fixation was needed except at the lowest contrast. Average fixation duration decreased and saccade amplitudes increased slightly with increasing contrast. The reduction of the number of fixations with increasing contrast suggests that visual span, i.e. the area from which information can be collected at one fixation, increases with increasing contrast. The reduction of the number of fixations together with reduced fixation duration result in reduced search times when contrast increases. |
Keith Rayner; Caren M Rotello; Andrew J Stewart; Jessica Keir; Susan A Duffy Integrating text and pictorial information: Eye movements when looking at print advertisements Journal Article Journal of Experimental Psychology: Applied, 7 (3), pp. 219–226, 2001. @article{Rayner2001, title = {Integrating text and pictorial information: Eye movements when looking at print advertisements}, author = {Keith Rayner and Caren M Rotello and Andrew J Stewart and Jessica Keir and Susan A Duffy}, doi = {10.1037/1076-898X.7.3.219}, year = {2001}, date = {2001-01-01}, journal = {Journal of Experimental Psychology: Applied}, volume = {7}, number = {3}, pages = {219--226}, abstract = {Viewers looked at print advertisements as their eye movements were recorded. Half of them were told to pay special attention to car ads, and the other half were told to pay special attention to skin-care ads. Viewers tended to spend more time looking at the text than the picture part of the ad, though they did spend more time looking at the type of ad they were instructed to pay attention to. Fixation durations and saccade lengths were both longer on the picture part of the ad than the text, but more fixations were made on the text regions. Viewers did not alternate fixations between the text and picture part of the ad, but they tended to read the large print, then the smaller print, and then they looked at the picture (although some viewers did an initial cursory scan of the picture). Implications for (a) how viewers integrate pictorial and textual information and (b) applied research and advertisement development are discussed.}, keywords = {}, pubstate = {published}, tppubtype = {article} } Viewers looked at print advertisements as their eye movements were recorded. Half of them were told to pay special attention to car ads, and the other half were told to pay special attention to skin-care ads. Viewers tended to spend more time looking at the text than the picture part of the ad, though they did spend more time looking at the type of ad they were instructed to pay attention to. Fixation durations and saccade lengths were both longer on the picture part of the ad than the text, but more fixations were made on the text regions. Viewers did not alternate fixations between the text and picture part of the ad, but they tended to read the large print, then the smaller print, and then they looked at the picture (although some viewers did an initial cursory scan of the picture). Implications for (a) how viewers integrate pictorial and textual information and (b) applied research and advertisement development are discussed. |
Eyal M Reingold; Neil Charness; Marc Pomplun; Dave M Stampe Visual span in expert chess players: Evidence from eye movements Journal Article Psychological Science, 12 (1), pp. 48–55, 2001. @article{Reingold2001, title = {Visual span in expert chess players: Evidence from eye movements}, author = {Eyal M Reingold and Neil Charness and Marc Pomplun and Dave M Stampe}, doi = {10.1111/1467-9280.00309}, year = {2001}, date = {2001-01-01}, journal = {Psychological Science}, volume = {12}, number = {1}, pages = {48--55}, abstract = {The reported research extends classic findings that after briefly viewing structured, but not random, chess positions, chess masters reproduce these positions much more accurately than lessskilled players. Using a combination of the gaze-contingent window paradigm and the change blindness flicker paradigm, we documented dramatically larger visual spans for experts while processing structured, but not random, chess positions. In addition, in a checkdetection task, a minimized 3 × 3 chessboard containing a King and potentially checking pieces was displayed. In this task, experts made fewer fixations per trial than less-skilled players, and had a greater proportion of fixations between individual pieces, rather than on pieces. Our results provide strong evidence for a perceptual encoding advantage for experts attributable to chess experience, rather than to a general perceptual or memory superiority.}, keywords = {}, pubstate = {published}, tppubtype = {article} } The reported research extends classic findings that after briefly viewing structured, but not random, chess positions, chess masters reproduce these positions much more accurately than lessskilled players. Using a combination of the gaze-contingent window paradigm and the change blindness flicker paradigm, we documented dramatically larger visual spans for experts while processing structured, but not random, chess positions. In addition, in a checkdetection task, a minimized 3 × 3 chessboard containing a King and potentially checking pieces was displayed. In this task, experts made fewer fixations per trial than less-skilled players, and had a greater proportion of fixations between individual pieces, rather than on pieces. Our results provide strong evidence for a perceptual encoding advantage for experts attributable to chess experience, rather than to a general perceptual or memory superiority. |