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Panoramic screen

The human visual field covers 180° horizontally but visual acuity is not uniform across the field of view. The density receptors, responsible for high-resolution perception, decreases considerably as eccentricity increases from the fovea. Their number drops to about 50% at 1.75° from the fovea and to less than 5% at 20° from the fovea and projections to visual cortex prioritize foveal inputs, resulting in a disproportionately large representation of central vision in the visual cortex whilst peripheral parts are less and less represented on the cortical surface as eccentricity increases. For technical reasons (the size of computer screens) little work has concentrated on studying perception in the peripheral visual field, particularly above 20° eccentricity. Yet, detection of relevant stimuli (e.g., a pedestrian crossing, a moving car, a fearful animal, a face in a crowd) at peripheral locations is important, not only for survival reactions. Indeed, despite its low spatial resolution peripheral vision provides critical information about the environment.

Our group (AVA team, member of SCALab) has developed a panoramic screen (5 meter diameter) covering the 180° of the human visual field with the objectives of (1) understanding the capabilities of peripheral vision for object, face and scene recognition at large eccentricities (above 20°) and (2) studying visual plasticity, especially how peripheral vision can be improved, in people who must rely on their peripheral vision due to a central scotoma (e.g. in macular degeneration).

We have shown that people with central vision loss due to age-related macular degeneration or to juvenile maculopathy (Stargardt disease) can recognize objects and photographs of scenes using their peripheral vision but we have observed no improvement of peripheral vision in people who had loss central vision since childhood. With normally sighted young people we have found that faces, objects and scenes can be recognized above chance at very large eccentricities (above 50°).

Our research is now oriented to the following questions:

-       Whether peripheral vision can be improved with perceptual learning

-       Whether using realistic environments and natural activities (e.g., object search, distance evaluation, visuo-spatial memory…) improve perception and action in people with central visual field loss (e.g., in maculopathies) or with peripheral visual field loss (e.g., in glaucoma)

-       Where in the brain is processed visual information displayed at very large eccentricities

Our group involves experts in visual neuroscience and ophthalmologists.

The “vision” laboratory is located in the university hospital of Lille in the departments of ophthalmology of Dr S Defoort (hospital Salengro) and Pr JF Rouland (hospital Huriez) and the hospital Saint Vincent de Paul (Dr THC Tran). Our main collaborators are Pr L Loschky (university of Kansas City), Pr M Hayhoe (University of Austin), Pr A McKendrick (university of Melbourne) and Drs C Peyrin  and N Guyader (university of Grenoble).

 

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