Description du projet
Des substrats neuraux du modèle bayésien de perception sensorielle
Toute la journée, nous sommes bombardés par un déferlement d’influx sensoriels. Ces processus pourraient être uniformisés via un modèle que le cerveau crée de notre monde, mis à jour avec l’expérience et utilisé pour faire des prédictions affectant nos réactions. Récemment, cette idée a été revue dans l’application de théories bayésiennes, proposées pour décrire la perception sensorielle saine ainsi que la capacité prédictive réduite liée à l’autisme de haut niveau. GenPercept cherche des mécanismes neuraux dans le traitement sensoriel normal et les troubles neuropsychiatriques en mettant l’accent sur les saccades et les oscillations rythmiques relevées dans l’activité cérébrale. Les scientifiques espèrent trouver le substrat neural impliqué dans notre réponse à la manière dont le passé influence notre perception présente.
Objectif
How do we rapidly and effortlessly compute a vivid veridical representation of the external world from the noisy and ambiguous input supplied by our sensors? One possibility is that the brain does not process all incoming sensory information anew, but actively generates a model of the world from past experience, and uses current sensory data to update that model. This classic idea has been well formulised within the modern framework of Generative Bayesian Inference. However, despite these recent theoretical and empirical advances, there is no definitive proof that generative mechanisms prevail in perception, and fundamental questions remain.
The ambitious aim of GenPercept is to establish the importance of generative processes in perception, characterise quantitatively their functional role, and describe their underlying neural mechanisms. With innovative psychophysical and pupillometry techniques, it will show how past perceptual experience is exploited to manage and mould sensory analysis of the present. With ultra-high field imaging, it will identify the underlying neural mechanisms in early sensory cortex. With EEG and custom psychophysics it will show how generative predictive mechanisms mediate perceptual continuity at the time of saccadic eye movements, and explore the innovative idea that neural oscillations reflect reverberations in the propagation of generative prediction and error signals. Finally, it will look at individual differences, particularly in autistic perception, where generative mechanisms show interesting atypicalities.
A full understanding of generative processes will lead to fundamental insights in understanding how we perceive and interact with the world, and how past perceptual experience influences what we perceive. The project is also of clinical relevance, as these systems are prone to dysfunction in several neuro-behavioural conditions, including autism spectrum disorder.
Champ scientifique
Programme(s)
Thème(s)
Régime de financement
ERC-ADG - Advanced GrantInstitution d’accueil
50121 Florence
Italie