Description du projet
De nouvelles informations sur l’activité complexe des réseaux corticaux
La communication neuronale au sein du cortex des mammifères demeure un mystère en neurosciences. Des recherches approfondies sur les réponses à des signaux environnementaux ont permis de fournir des données importantes à ce sujet, mais elles reposent principalement sur des études de cellules individuelles. Ces preuves ne permettent pas d’envisager la complexité et la dynamique des réseaux neuronaux. Afin de répondre à ces limitations et de dévoiler la communication entre les populations de cellules intermélangées du cortex, le projet KiloNeurons, financé par l’UE, propose de surveiller l’activité de milliers de neurones simultanément. Les données obtenues serviront à développer et à affiner des modèles théoriques de calculs corticaux au sein du cerveau des mammifères.
Objectif
A major goal in neuroscience is to understand neural computation in the mammalian cortex. Since the 1950s, we have learnt how cells respond to changes in the environment but the cells have largely been observed one at a time. However, single-cell recording cannot access the complexity of distributed processing and coding in the large, intermixed cell populations of the cortex. To understand this complexity, we need population-wide activity measurements, at single-cell resolution, as well as theoretical models to interpret the data. In this project, we shall combine experiments and theory to enable a paradigmatic shift from single-cell to population analysis for a prototypical high-level cortical system, the navigation system of the mammalian medial entorhinal-hippocampal region. In this system, spatial firing correlates of individual cells are so evident that they have been given simple, descriptive names – such as place cells, grid cells, and head direction cells. The wealth of information on the phenomenology of these cells, and the existence of theoretical frameworks that offer strong predictions on their population-wide activity patterns, renders the system perfect for population-level analyses of cortical computation. We shall introduce experimental tools to obtain the amount and specificity of multi-neuron data required to decipher neural population codes in freely navigating rodents. Guided initially by theory on attractor network dynamics, we shall identify regularities in firing and connectivity patterns of thousands of simultaneously monitored neurons and use the data to test, refine and develop theoretical models. This exercise will be extended to less-understood high-end systems such as lateral entorhinal cortex, where computational operations have remained elusive due to the lack of similar single-cell correlates. The project is transformative in that it will uncover fundamental and general mechanisms of high-end cortical population coding in mammals.
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ERC-SyG - Synergy grantInstitution d’accueil
7491 Trondheim
Norvège