Hemispheric specialization, retinotopic mapping and retino-cortical interaction during scene perception – RECOR

The RECOR program aims to investigate the visual and neural mechanisms involved in the processing of natural scenes, through behavioural and functional Magnetic Resonance Imaging (fMRI) investigations on healthy participants and patients with retinal diseases. Therefore, we aim to develop visual tests (based on natural scene image categorization) for the diagnosis of visual deficits and the monitoring of treatments in retinal diseases such as Age-related Macular Degeneration (AMD) and Retinitis Pigmentosa (RP) with the investigation of the functional cerebral reorganization of these patients, using fMRI. For this purpose, we will first investigate on healthy participants the hemispheric specialization and retinotopic mapping of spatial frequency processing during scene perception using for the first time large scenes (> 24° of visual angle) which cover a large part of the visual field and movies of these scenes that experimentally “mimic” the sequential processing of spatial frequencies within the visual system ('coarse-to-fine' scheme). Studies will also be conducted on children (4 to 10 years) and aged participants (50 to 70 years) to precise the mechanisms of spatial frequency processing in childhood and normal aging. Then, we will focus on the retino-cortical interaction during scene perception through the investigation of the visual deficits for spatial frequency processing in two contrasted retinal diseases (AMD patients with a central retinal lesion and RP patients with a more peripheral retinal lesion) and the changes in the brain and the retinotopic maps of the visual cortical areas after a lesion of the retina. Finally, we will assess the effect of an anti-VEGF treatment (Ranibizumab) used in the treatment of wet type AMD on the functional cerebral reorganization of these patients. The achievement of this project will have a strong theoretical impact on models of scene perception, and will contribute to improve the children teaching programs (such in reading), the quality of life for older people, and the ophthalmological rehabilitation with novel tools for the diagnostic and the monitoring of future treatments in retinal diseases.