Functional organization of the multisensory motion system

Description du projet

Revisiter le système visuel du mouvement

Le cerveau humain possède la capacité remarquable de percevoir le mouvement, une caractéristique centrale pour un développement cérébral sain. Les individus présentant une capacité réduite à détecter et à traiter le mouvement éprouvent des difficultés dans leurs activités quotidiennes. Le projet ItsAllAboutMotion financé par l’UE compte étudier le système de traitement visuel du mouvement et son fonctionnement en réponse à différents stimuli sensoriels. À l’aide de méthodologies avancées, les chercheurs identifieront et caractériseront les régions du cerveau impliquées dans le traitement du mouvement et élucideront leur rôle dans sa perception. Le fait que les régions cérébrales sensibles au mouvement soient susceptibles d’exhiber des réponses sensorielles indépendantes devrait pousser à repenser les stratégies de réhabilitation existantes chez les personnes déficientes du point de vue sensoriel.

Objectif

One of the most significant current discussions in the understanding of the human brain is the functional recruitment of some regions of the cortex for specific tasks, regardless the sensory modality (e.g. visual, tactile or auditory) in which the stimuli is received. The ability to perceive motion, among others visual properties, is a fundamental faculty of the human brain. The predisposition to detect motion is present since the first months of life and is one of the main prerequisites for a child’s healthy brain development. Brain lesions that impair the detection and processing of motion have a profound impact on daily activity. Consequently, visual motion processing is one of the most fundamental and well-studied systems in the human brain, canonically known to develop mainly for the purpose of visual perception. The aim of this proposal is to elucidate in humans whether the functional recruitment and specialization of the visual motion system is independent of the sensory modality in which the stimuli are perceived, to characterize the sensory independent functional mesoscopic architecture within the brain regions involved and to establish their causal role in perception. I will answer these questions using advanced methods such as ultra-high field fMRI at 7T, intracranial electrodes, transcranial magnetic stimulation and advanced neural based analyses. The integrated approach I propose here provides a unique multiangle perspective to investigate the neural substrate of multisensory processes. The fact that motion sensitive brain regions exhibit sensory-independent responses and that the same neuronal ensemble may respond to aspecific sensory features will challenge our notions on brain sensory segregation and functional development and will impact other high-level cognition studies at large. Moreover, it will provide essential knowledge for novel research on sensory substitution devices for rehabilitation in sensory-impaired individuals.