Visual field recovery after vision restoration therapy (VRT) is independent of eye movements: An eye tracker study

2006 ◽  
Vol 175 (1) ◽  
pp. 18-26 ◽  
Author(s):  
Erich Kasten ◽  
Ulrike Bunzenthal ◽  
Bernhard A. Sabel
2021 ◽  
Vol 15 ◽  
Author(s):  
Scott W. J. Mooney ◽  
Nazia M. Alam ◽  
Glen T. Prusky

Visual deficits in children that result from brain injury, including cerebral/cortical visual impairment (CVI), are difficult to assess through conventional methods due to their frequent co-occurrence with cognitive and communicative disabilities. Such impairments hence often go undiagnosed or are only determined through subjective evaluations of gaze-based reactions to different forms, colors, and movements, which limits any potential for remediation. Here, we describe a novel approach to grading visual health based on eye movements and evidence from gaze-based tracking behaviors. Our approach—the “Visual Ladder”—reduces reliance on the user’s ability to attend and communicate. The Visual Ladder produces metrics that quantify spontaneous saccades and pursuits, assess visual field responsiveness, and grade spatial visual function from tracking responses to moving stimuli. We used the Ladder to assess fourteen hospitalized children aged 3 to 18 years with a diverse range of visual impairments and causes of brain injury. Four children were excluded from analysis due to incompatibility with the eye tracker (e.g., due to severe strabismus). The remaining ten children—including five non-verbal children—were tested multiple times over periods ranging from 2 weeks to 9 months, and all produced interpretable outcomes on at least three of the five visual tasks. The results suggest that our assessment tasks are viable in non-communicative children, provided their eyes can be tracked, and hence are promising tools for use in a larger clinical study. We highlight and discuss informative outcomes exhibited by each child, including directional biases in eye movements, pathological nystagmus, visual field asymmetries, and contrast sensitivity deficits. Our findings indicate that these methodologies will enable the rapid, objective classification and grading of visual impairments in children with CVI, including non-verbal children who are currently precluded from most vision assessments. This would provide a much-needed differential diagnostic and prognostic tool for CVI and other impairments of the visual system, both ocular and cerebral.


1997 ◽  
Vol 9 (2) ◽  
pp. 191-202 ◽  
Author(s):  
R. W. Kentridge ◽  
C. A. Heywood ◽  
L. Weiskrantz

There is an important new proposal that “blindsight”-the ability to detect and identify visual stimuli by forcedchoice guessing and in the absence of conscious awareness when they fall in blind regions of the visual field—is a function of residual “islands” of undamaged visual cortex. This stands in contrast to the widely accepted view that blindsight is exclusively a function of secondary visual pathways. According to the new view, residual vision in blindsight should be patchy. Thus, when apparently wide areas of residual vision in blindsight are found, these may be due to eye-movements that allow stimuli to pass over retinal locations corresponding to islands of sparing. We tested this hypothesis by examining the distribution of residual vision in blindsight when the effects of eye movements on the retinal location of stimuli were minimized. We report a series of experiments that examined twealternate forcedchoice discrimination in the blind field of the subject GY. Using a dual-Purkinje image eye-tracker we applied three methods of minimizing the effects of retinal slippage due to eye-movements on discrimination performance: fixation stability-dependent trials, software image stabilization, and post hoc rejection of trials in which saccadic eye-movements were detected. In the first experiment, GY's discrimination performance was significantly above chance in 8 of 15 locations tested. In the subsequent experiments the subject knew the location of the target in each block of trials, and this resulted in improvements to performance in a further three locations. Increasing the luminance of the stimulus display (while maintaining 95% target contrast), and increasing the temporal discriminability of the forced choice produced performance above chance in all but two of the locations tested. The consistent chance performance observed in two locations in the lower visual field nevertheless implies that GY's blindsight does not extend over the whole of his scotoma. Nevertheless, abolishing, or minimizing, the effects of eye-movements did not result in a loss of detection in all the widely separated regions tested, and we thus conclude that GY's blindsight cannot adequately be explained in terms of islands of spared vision. Islands may account for residual vision in scotomata in some patients, but cannot be a universal account of the phenomenon of blindsight.


PLoS ONE ◽  
2020 ◽  
Vol 15 (11) ◽  
pp. e0242009
Author(s):  
Chuan Luo ◽  
John M. Franchak

Infants’ visual experiences are important for learning, and may depend on how information is structured in the visual field. This study examined how objects are distributed in 12-month-old infants’ field of view in a mobile play setting. Infants wore a mobile eye tracker that recorded their field of view and eye movements while they freely played with toys and a caregiver. We measured how centered and spread object locations were in infants’ field of view, and investigated how infant posture, object looking, and object distance affected the centering and spread. We found that far toys were less centered in infants’ field of view while infants were prone compared to when sitting or upright. Overall, toys became more centered in view and less spread in location when infants were looking at toys regardless of posture and toy distance. In sum, this study showed that infants’ visual experiences are shaped by the physical relation between infants’ bodies and the locations of objects in the world. However, infants are able to compensate for postural and environmental constraints by actively moving their head and eyes when choosing to look at an object.


2012 ◽  
Vol 17 (4) ◽  
pp. 257-265 ◽  
Author(s):  
Carmen Munk ◽  
Günter Daniel Rey ◽  
Anna Katharina Diergarten ◽  
Gerhild Nieding ◽  
Wolfgang Schneider ◽  
...  

An eye tracker experiment investigated 4-, 6-, and 8-year old children’s cognitive processing of film cuts. Nine short film sequences with or without editing errors were presented to 79 children. Eye movements up to 400 ms after the targeted film cuts were measured and analyzed using a new calculation formula based on Manhattan Metrics. No age effects were found for jump cuts (i.e., small movement discontinuities in a film). However, disturbances resulting from reversed-angle shots (i.e., a switch of the left-right position of actors in successive shots) led to increased reaction times between 6- and 8-year old children, whereas children of all age groups had difficulties coping with narrative discontinuity (i.e., the canonical chronological sequence of film actions is disrupted). Furthermore, 4-year old children showed a greater number of overall eye movements than 6- and 8-year old children. This indicates that some viewing skills are developed between 4 and 6 years of age. The results of the study provide evidence of a crucial time span of knowledge acquisition for television-based media literacy between 4 and 8 years.


2018 ◽  
Author(s):  
Fatima Maria Felisberti

Visual field asymmetries (VFA) in the encoding of groups rather than individual faces has been rarely investigated. Here, eye movements (dwell time (DT) and fixations (Fix)) were recorded during the encoding of three groups of four faces tagged with cheating, cooperative, or neutral behaviours. Faces in each of the three groups were placed in the upper left (UL), upper right (UR), lower left (LL), or lower right (LR) quadrants. Face recognition was equally high in the three groups. In contrast, the proportion of DT and Fix were higher for faces in the left than the right hemifield and in the upper rather than the lower hemifield. The overall time spent looking at the UL was higher than in the other quadrants. The findings are relevant to the understanding of VFA in face processing, especially groups of faces, and might be linked to environmental cues and/or reading habits.


1980 ◽  
Vol 50 (2) ◽  
pp. 631-636
Author(s):  
Evans Mandes

Post-exposural eye movements were studied in 32 adults and 24 7-yr.-old children. Stimuli were binary figures exposed tachistoscopically in both visual fields simultaneously. The data showed significant correlations between direction of eye movement and locus of recognition for both children and adults. No significant differences were found in frequencies of eye movements of children and adults. The data are interpreted in terms of the facilitative effects of post-exposural eye movements upon perception for both groups.


2014 ◽  
Vol 519-520 ◽  
pp. 828-832
Author(s):  
He Shan Liu ◽  
Xun Chen ◽  
Jun Zhou ◽  
Wei Liu

In today’s marketplace, external appearance and internal decoration become an increasingly important factor that affecting sales volume of product. Moreover, for loaders, the external appearance and decoration of the cab may influence the driver’s comfort both visually and mentally. In order to find out how it works, we divided the experimental subjects into professional group and nonprofessional group and used eye tracker to record subjects’ responses (eye movements) to the pictures of the loader, and then analyzed these responses with the eye tracker build-in analyzing software. The results show that the professional are more interested in functional parts and the nonprofessionals are more likely to be influenced by appearance shape and color; the instrument panel is less attracted during the whole experiments.


Healthcare ◽  
2020 ◽  
Vol 9 (1) ◽  
pp. 10
Author(s):  
Chong-Bin Tsai ◽  
Wei-Yu Hung ◽  
Wei-Yen Hsu

Optokinetic nystagmus (OKN) is an involuntary eye movement induced by motion of a large proportion of the visual field. It consists of a “slow phase (SP)” with eye movements in the same direction as the movement of the pattern and a “fast phase (FP)” with saccadic eye movements in the opposite direction. Study of OKN can reveal valuable information in ophthalmology, neurology and psychology. However, the current commercially available high-resolution and research-grade eye tracker is usually expensive. Methods & Results: We developed a novel fast and effective system combined with a low-cost eye tracking device to accurately quantitatively measure OKN eye movement. Conclusions: The experimental results indicate that the proposed method achieves fast and promising results in comparisons with several traditional approaches.


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