Role of Peripheral Vision in Scene Perception (PERISCE)

Despite its low spatial resolution, peripheral vision is very useful for rapidly categorizing a visual scene. Low spatial frequencies of a visual stimulus available in peripheral vision would allow a coarse categorization of the scene and objects (deciding, for example, whether it is an urban or natural landscape). This first representation would then trigger predictive mechanisms which would subsequently guide a more detailed visual analysis in central vision. The psychophysical studies that the investigators have already conducted in this scientific context has been carried out under normal vision conditions. The objective of this project is to study the influence of peripheral vision on central vision with an original approach: What are the consequences of a loss of peripheral vision on the processing performed in central vision? The project will concern patients with glaucoma. This ophthalmic pathology particularly affects the peripheral retina and thus represents a good pathological cognitive model of a visual recognition system in which peripheral vision is less important. The investigators will conduct psychophysical studies with glaucomatous patients and healthy volunteers with normal vision. All participants will be required to perform a short experiment on a computer (15 minutes) where they will look at different photographs of scenes of different luminance and spatial frequencies. Participants will have to perform various tasks on these images using the keys on the keyboard.