scholarly journals Visual search without central vision – no single pseudofovea location is best

2014 ◽  
Vol 7 (2) ◽  
Author(s):  
Angelika Lingnau ◽  
Thorsten Albrecht ◽  
Jens Schwarzbach ◽  
Dirk Vorberg
Keyword(s):  
Visual Search ◽  
Macular Degeneration ◽  
Spatial Resolution ◽  
Central Vision ◽  
Foveal Vision ◽  
Scan Path ◽  
Path Direction ◽  
Retinal Region ◽  
Field Location

We typically fixate targets such that they are projected onto the fovea for best spatial resolution. Macular degeneration patients often develop fixation strategies such that targets are projected to an intact eccentric part of the retina, called pseudofovea. A longstanding debate concerns which pseudofovea-location is optimal for non-foveal vision. We examined how pseudofovea position and eccentricity affect performance in visual search, when vision is restricted to an off-foveal retinal region by a gaze-contingent display that dynamically blurs the stimulus except within a small viewing window (forced field location). Trained normally sighted participants were more accurate when forced field location was congruent with the required scan path direction; this contradicts the view that a single pseudofovea location is generally best. Rather, performance depends on the congruence between pseudofovea location and scan path direction.

Does Perisaccadic Compression Require Foveal Vision?

Perception ◽  
10.1068/p7666 ◽  
2014 ◽  
Vol 43 (11) ◽  
pp. 1214-1224
Author(s):  
Maria Matziridi ◽  
Mijke O Hartendorp ◽  
Eli Brenner ◽  
Jeroen B J Smeets
Keyword(s):  
Macular Degeneration ◽  
Systematic Errors ◽  
High Density ◽  
Retinal Locus ◽  
Central Vision ◽  
Foveal Vision ◽  
Central Retina

People make systematic errors when localizing a stimulus that is presented briefly near the time of a saccade. These errors have been interpreted as compression towards the position that is fixated after the saccade. Normally, fixating a position means that its image falls on the fovea. Macular degeneration (MD) damages the central retina, obliterating foveal vision. Many people with MD adopt a new retinal locus for fixation, called the preferred retinal locus (PRL). If the compression of space during the saccade is a special characteristic of the fovea, possibly due to the high density of cones that is found in the fovea, one might expect people lacking central vision to show no compression of space around the time of a saccade. If the compression of space during the saccade is related to the position that is fixated after the saccade, one would expect compression towards the PRL, despite the lack of a high density of cones in this area. We found that a person with MD showed a clear compression towards her PRL. We conclude that perisaccadic compression is related to the position that is fixated after the saccade rather than to the high density of receptors in the fovea.

scholarly journals Photovoltaic Restoration of Central Vision in Atrophic Age-Related Macular Degeneration

Ophthalmology ◽  
2020 ◽  
Vol 127 (8) ◽  
pp. 1097-1104 ◽  
Author(s):  
Daniel Palanker ◽  
Yannick Le Mer ◽  
Saddek Mohand-Said ◽  
Mahiul Muqit ◽  
Jose A. Sahel
Keyword(s):  
Macular Degeneration ◽  
Age Related Macular Degeneration ◽  
Central Vision ◽  
Age Related

scholarly journals Training eye movements for visual search in individuals with macular degeneration

2016 ◽  
Vol 16 (15) ◽  
pp. 29 ◽  
Author(s):  
Christian P. Janssen ◽  
Preeti Verghese
Keyword(s):  
Visual Search ◽  
Eye Movements ◽  
Macular Degeneration

scholarly journals Visual Search with Image Modification in Age-Related Macular Degeneration

2012 ◽  
Vol 53 (10) ◽  
pp. 6600 ◽  
Author(s):  
Emily Wiecek ◽  
Mary Lou Jackson ◽  
Steven C. Dakin ◽  
Peter Bex
Keyword(s):  
Visual Search ◽  
Macular Degeneration ◽  
Age Related Macular Degeneration ◽  
Age Related

scholarly journals Simulated loss of foveal vision eliminates visual search advantage in repeated displays

2012 ◽  
Vol 6 ◽  
Author(s):  
Franziska Geringswald ◽  
Florian Baumgartner ◽  
Stefan Pollmann
Keyword(s):  
Visual Search ◽  
Foveal Vision

scholarly journals Seeing the world through the eyes of a butterfly: visual ecology of the territorial males of Pararge aegeria (Lepidoptera: Nymphalidae)

2021 ◽  
Author(s):  
Martin Bergman ◽  
Jochen Smolka ◽  
Dan-Eric Nilsson ◽  
Almut Kelber
Keyword(s):  
Visual Field ◽  
Spatial Resolution ◽  
Visual Environment ◽  
Sexually Dimorphic ◽  
European Forests ◽  
Head Posture ◽  
Pararge Aegeria ◽  
Visual Systems ◽  
The World ◽  
Retinal Region

AbstractCombining studies of animal visual systems with exact imaging of their visual environment can get us a step closer to understand how animals see their “Umwelt”. Here, we have combined both methods to better understand how males of the speckled wood butterfly, Pararge aegeria, see the surroundings of their perches. These males are well known to sit and wait for a chance to mate with a passing females, in sunspot territories in European forests. We provide a detailed description of the males' body and head posture, viewing direction, visual field and spatial resolution, as well as the visual environment. Pararge aegeria has sexually dimorphic eyes, the smallest interommatidial angles of males are around 1°, those of females 1.5°. Perching males face the antisolar direction with their retinal region of the highest resolution pointing at an angle of about 45° above the horizon; thus, looking at a rather even and dark background in front of which they likely have the best chance to detect a sunlit female passing through the sunspot.

scholarly journals Reliance on central vs. peripheral vision for visual search in younger and older adults

2020 ◽  
Author(s):  
Anne-Sophie Laurin ◽  
Julie Ouerfelli-Éthier ◽  
Laure Pisella ◽  
Aarlenne Zein Khan
Keyword(s):  
Older Adults ◽  
Visual Search ◽  
Peripheral Vision ◽  
Reaction Times ◽  
Central Vision ◽  
Younger Adults ◽  
Serial Search ◽  
Attentional Resources ◽  
Search Tasks ◽  
Fixation Durations

Older adults show declines performing visual search, but their nature is unclear. We propose that it is related to greater attentional reliance on central vision. To investigate this, we tested how occluding central vision would affect younger and older adults in visual search. Participants (14 younger, M = 21.6 years; 16 older, M = 69.6 years) performed pop-out and serial search tasks in full view and with different sized gaze-contingent artificial central scotomas (no scotoma, 3°, 5° or 7° diameter).In pop-out search, older adults showed longer search times for peripheral targets during full viewing. Their reaction times, saccades and fixation durations also increased as a function of scotoma size, contrary to younger adults. These declines may reflect a relative impairment in peripheral visual attention for global processing in aging.In serial search, despite older adults being generally slower, we found no difference between groups in reaction time increases for eccentric targets and for bigger scotomas. These results may come from the difficulty of serial search, in which both groups used centrally limited attentional windows.We conclude that older adults allocate more attentional resources towards central vision compared to younger adults, impairing their peripheral processing primarily in pop-out visual search.

scholarly journals An Eye Tracking Analysis on Diagnostic Performance of Digital Fundus Photography Images between Ophthalmologists and Optometrists

2019 ◽  
Vol 17 (1) ◽  
pp. 30
Author(s):  
Mizhanim Mohamad Shahimin ◽  
Azalia Razali
Keyword(s):  
Visual Search ◽  
Eye Movement ◽  
Correct Diagnosis ◽  
Fundus Photography ◽  
Eye Tracker ◽  
Total Fixation ◽  
Search Patterns ◽  
Scan Path ◽  
Scan Paths ◽  
Fundus Photographs

To investigate the parameters of eye movement between ophthalmologists and optometrists while diagnosing digital fundus photographs, sixteen participants (eight ophthalmologists and eight optometrists) were recruited in this study. Every participant’s eye movement during diagnosis of a randomized set of fundus photographs displayed on an eye tracker were recorded. Fixation metrics (duration, count and rate) and scan path patterns were extracted from the eye tracker. These parameters of eye movement and correct diagnosis score were compared between both groups. Correlation analyses between fixation metrics and correct diagnosis score were also performed. Although fixation metrics between ophthalmologists and optometrists were not statistically different (p > 0.05), these parameters were statistically different when compared between different area of interests. Both participant groups had a similar correct diagnosis score. No correlation was found between fixation metrics and correct diagnosis score between both groups, except for total fixation duration and ophthalmologists’ diagnosis score of diabetic retinopathy photographs. The ophthalmologists’ scan paths were simpler, with larger saccades, and were distributed at the middle region of the photographs. Conversely, optometrists’ scan paths were extensive, with shorter saccades covering wider fundus areas, and were accumulated in some unrelated fundus areas. These findings indicated comparable efficiency and systematic visual search patterns between both the groups. Understanding visual search strategy could expedite the creation of a novel training routine for interpretation of ophthalmic diagnostic imaging.

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