-
Vision Research Oct 2006Precise binocular alignment of the visual axes is of utmost importance for good vision. The fact that so few of us ever experience diplopia is evidence of how well the... (Review)
Review
Precise binocular alignment of the visual axes is of utmost importance for good vision. The fact that so few of us ever experience diplopia is evidence of how well the oculomotor system performs this function in the face of changes due to development, disease and injury. The capacity of the oculomotor system to adapt to visual stimuli that mimic alignment deficits has been extensively explored in laboratory experiments. While the present paper reviews many of those studies, the primary focus is on issues involved in maintaining good vertical and torsional alignment in everyday viewing situations where the parsing of muscle forces may vary for the same horizontal and vertical eye positions due to changes in horizontal vergence and head posture.
Topics: Eye Movements; Fixation, Ocular; Head Movements; Humans; Pursuit, Smooth; Rotation; Torsion Abnormality; Vision, Binocular
PubMed: 16879856
DOI: 10.1016/j.visres.2006.06.005 -
Journal of Vision Oct 2020Attending to peripheral visual targets while maintaining central fixation, a process that involves covert attention, reduces fixation stability. Here, we tested the...
Attending to peripheral visual targets while maintaining central fixation, a process that involves covert attention, reduces fixation stability. Here, we tested the hypothesis that changes in fixation stability induced by peripheral viewing contribute to crowding in peripheral vision by increasing positional uncertainty. We first assessed whether fixation was less stable during peripheral versus central (foveal) viewing for both crowded and uncrowded stimuli. We then tested whether fixation stability during peripheral viewing was associated with the extent of crowding. Fourteen participants performed a tumbling E orientation discrimination task at three different eccentricities (0°, 5°, 10°). The target was presented with or without flankers. Fixational eye movements were measured using an infrared video-based eyetracker. A central fixation cross was provided for the two peripheral viewing conditions, and optotype size was scaled for each eccentricity. Discrimination of appropriately scaled uncrowded stimuli was unaffected by eccentricity, whereas discrimination of crowded stimuli deteriorated dramatically with eccentricity, despite scaling. Both crowded and uncrowded peripheral stimuli were associated with reduced fixation stability, increased microsaccadic amplitude, and a greater proportion of horizontal microsaccades relative to centrally presented stimuli. However, these effects were not associated with the magnitude of crowding. This suggests that reduced fixation stability due to peripheral viewing does not contribute to crowding in peripheral vision.
Topics: Adult; Female; Fixation, Ocular; Humans; Male; Orientation, Spatial; Visual Perception
PubMed: 33007078
DOI: 10.1167/jov.20.10.3 -
Journal of Vision Jan 2014A large body of previous models to predict where people look in natural scenes focused on pixel-level image attributes. To bridge the semantic gap between the predictive...
A large body of previous models to predict where people look in natural scenes focused on pixel-level image attributes. To bridge the semantic gap between the predictive power of computational saliency models and human behavior, we propose a new saliency architecture that incorporates information at three layers: pixel-level image attributes, object-level attributes, and semantic-level attributes. Object- and semantic-level information is frequently ignored, or only a few sample object categories are discussed where scaling to a large number of object categories is not feasible nor neurally plausible. To address this problem, this work constructs a principled vocabulary of basic attributes to describe object- and semantic-level information thus not restricting to a limited number of object categories. We build a new dataset of 700 images with eye-tracking data of 15 viewers and annotation data of 5,551 segmented objects with fine contours and 12 semantic attributes (publicly available with the paper). Experimental results demonstrate the importance of the object- and semantic-level information in the prediction of visual attention.
Topics: Adolescent; Adult; Attention; Computer Simulation; Eye Movements; Fixation, Ocular; Humans; Pattern Recognition, Visual; Young Adult
PubMed: 24474825
DOI: 10.1167/14.1.28 -
Vision Research Feb 2019During reading, eye movement patterns differ between children and adults. Children make more fixations that are longer in duration and make shorter saccades....
During reading, eye movement patterns differ between children and adults. Children make more fixations that are longer in duration and make shorter saccades. Return-sweeps are saccadic eye movements that move a reader's fixation to a new line of text. Return-sweeps move fixation further than intra-line saccades and often undershoot their target. This necessitates a corrective saccade to bring fixation closer to the start of the line. There have been few empirical investigations of return-sweep saccades in adults, and even fewer in children. In the present study, we examined return-sweeps of 47 adults and 48 children who read identical multiline texts. We found that children launch their return-sweeps closer to the end of the line and target a position closer to the left margin. Therefore, children fixate more extreme positions on the screen when reading for comprehension. Furthermore, children required a corrective saccade following a return-sweep more often than adults. Analysis of the duration of the fixation preceding the corrective saccade indicated that children are as efficient as adults at responding to retinal feedback following a saccade. Rather than consider differences in adult's and children's return-sweep behaviour an artefact of oculomotor control, we believe that these differences represent adult's ability to utilise parafoveal processing to encode text at extreme positions.
Topics: Adolescent; Adult; Child; Female; Fixation, Ocular; Humans; Male; Oculomotor Muscles; Reading; Saccades; Young Adult
PubMed: 30625336
DOI: 10.1016/j.visres.2018.12.007 -
Proceedings. Biological Sciences Feb 2019According to the natural pedagogy theory, infant gaze following is based on an understanding of the communicative intent of specific ostensive cues. However, it has...
According to the natural pedagogy theory, infant gaze following is based on an understanding of the communicative intent of specific ostensive cues. However, it has remained unclear how eye contact affects this understanding and why it induces gaze following behaviour. In this study, we examined infant arousal in different gaze following contexts and whether arousal levels during eye contact predict gaze following. Twenty-five infants, ages 9-10 months participated in this study. They watched a video of an actress gazing towards one of two objects and then either looking directly into the camera to make eye contact or not showing any communicative intent. We found that eye contact led to an elevation in the infants' heart rates (HRs) and that HR during eye contact was predictive of later gaze following. Furthermore, increases in HR predicted gaze following whether it was accompanied by communicative cues or not. These findings suggest that infant gaze following behaviour is associated with both communicative cues and physiological arousal.
Topics: Arousal; Attention; Cues; Female; Fixation, Ocular; Humans; Infant; Male
PubMed: 30963922
DOI: 10.1098/rspb.2018.2746 -
Consciousness and Cognition Oct 2017The power of music is a literary topos, which can be attributed to intense and personally significant experiences, one of them being the state of absorption. Such...
The power of music is a literary topos, which can be attributed to intense and personally significant experiences, one of them being the state of absorption. Such phenomenal states are difficult to grasp objectively. We investigated the state of musical absorption by using eye tracking. We utilized a load related definition of state absorption: multimodal resources are committed to create a unified representation of music. Resource allocation was measured indirectly by microsaccade rate, known to indicate cognitive processing load. We showed in Exp. 1 that microsaccade rate also indicates state absorption. Hence, there is cross-modal coupling between an auditory aesthetic experience and fixational eye movements. When removing the fixational stimulus in Exp. 2, saccades are no longer generated upon visual input and the cross-modal coupling disappeared. Results are interpreted in favor of the load hypothesis of microsaccade rate and against the assumption of general slowing by state absorption.
Topics: Adult; Auditory Perception; Eye Movement Measurements; Female; Fixation, Ocular; Humans; Male; Music; Pleasure; Saccades; Young Adult
PubMed: 28787663
DOI: 10.1016/j.concog.2017.07.009 -
Journal of Vision Jun 2018Micromovements of the eye during visual fixations provide clues about how our visual system acquires information. The analysis of fixational eye movements can thus serve...
Micromovements of the eye during visual fixations provide clues about how our visual system acquires information. The analysis of fixational eye movements can thus serve as a noninvasive means to detect age-related or pathological changes in visual processing, which can in turn reflect associated cognitive or neurological disorders. However, the utility of such diagnostic approaches relies on the quality and usability of detection methods applied for the eye movement analysis. Here, we propose a novel method for (micro)saccade detection that is resistant to high-frequency recording noise, a frequent problem in video-based eye tracking in either aged subjects or subjects suffering from a vision-related pathology. The method is fast, it does not require manual noise removal, and it can work with position, velocity, or acceleration features, or a combination thereof. The detection accuracy of the proposed method is assessed on a new dataset of manually labeled recordings acquired from 14 subjects of advanced age (69-81 years old), performing an ocular fixation task. It is demonstrated that the detection accuracy of the new method compares favorably to that of two frequently used reference methods and that it is comparable to the best of the two algorithms when tested on an existing low-noise eye-tracking dataset.
Topics: Aged; Aged, 80 and over; Algorithms; Female; Fixation, Ocular; Humans; Male; Noise; Saccades; Visual Pathways; Visual Perception
PubMed: 30029229
DOI: 10.1167/18.6.19 -
Vision Research Sep 2014Pre-saccadic fixation durations associated with saccades directed in different directions were compared in three endogenous-attention oriented saccadic scanning tasks...
Pre-saccadic fixation durations associated with saccades directed in different directions were compared in three endogenous-attention oriented saccadic scanning tasks (i.e. visual search and scene viewing). Pre-saccadic fixation durations were consistently briefer before the execution of upward saccades, than downward saccades. Saccades also had a higher probability of being directed upwards than downwards. Pre-saccadic fixation durations were symmetric and longer for horizontally-directed saccades. The vertical visual field asymmetry in pre-saccadic fixation durations reflects an influence of factors not directly related to currently fixated elements. The ability to predict pre-saccadic fixation durations is important for computational modelling of real-time saccadic scanning, and the findings make a case for including directional constraints in computational modelling of when the eyes move.
Topics: Adult; Analysis of Variance; Attention; Female; Fixation, Ocular; Humans; Male; Middle Aged; Photic Stimulation; Saccades; Visual Fields; Young Adult
PubMed: 25094053
DOI: 10.1016/j.visres.2014.07.012 -
Perception 2007
Topics: Depth Perception; Eye Movements; Fixation, Ocular; Head Movements; Humans; Motion Perception; Vision Disparity
PubMed: 17844961
DOI: 10.1068/p3607ed -
Journal of Vision Apr 2018In this study, we investigated the influence of gaze and prior knowledge about the reach target on the use of allocentric information for memory-guided reaching....
In this study, we investigated the influence of gaze and prior knowledge about the reach target on the use of allocentric information for memory-guided reaching. Participants viewed a breakfast scene with five objects in the background and six objects on the table. Table objects served as potential reach targets. Participants first encoded the scene and, after a short delay, a test scene was presented with one table object missing and one, three, or five table objects horizontally shifted in the same direction. Participants performed a memory-guided reaching movement toward the position of the missing object on a blank screen. In order to examine the influence of gaze, participants either freely moved their gaze (free-view) or kept gaze at a fixation point (fixation) throughout the trial. The effect of prior knowledge was investigated by informing participants about the reach target either before (preview) or after (nonpreview) scene encoding. Our results demonstrate that humans use allocentric information for reaching even if a stable retinal reference is available. However, allocentric coding of reach targets is stronger when gaze is free and prior knowledge about the reach target is missing.
Topics: Adult; Computer Simulation; Cues; Female; Fixation, Ocular; Humans; Male; Memory, Short-Term; Mental Recall; Psychomotor Performance; Space Perception; Young Adult
PubMed: 29710312
DOI: 10.1167/18.4.22