En esta nueva exposición de nuestro ciclo de "Seminarios de Neurociencia", el Dr. Ulises Pereira del Center for Neural Science, New York University., expone sobre los mecanismos de circuitos neuronales multirregionales subyacentes a la toma de decisiones.
Abstract: Neuroscience is advancing at a breakneck pace into a big data era. Science consortiums, as well as large-scale lab collaborations, are producing ever-more-precise connectomes. In parallel, high-density probes now make it possible to record in the entire mouse brain during behavior by coordinating measurements across several labs. In physics, similar large-scale collaborations have been extremely successful. However, unlike physics, in which experimental discoveries go hand-to-hand with theoretical developments, in neuroscience, theories for multi-regional neural computations are seldom being developed. In this talk, I will present two projects in which we combine theory, electrophysiology, behavior, and data analysis for understanding decision-making at a multiregional scale. In the first project, we investigate the neuronal mechanisms for deciding when to act in a self-initiated action task. We show that in this task, ensemble activity in M2 unfolds through reliable discrete pattern sequences, however, with highly variable dwell times. We propose a two-area network model in which correlated variability drives meta-stable attractors sequences reproducing several aspects of neuronal recordings in M2. In the second project, we probe two contrasting theories for the circuit mechanism for action value maintenance and update during value-based decision-making. In the first theory, action value is maintained in the synapses, and rewards trigger dopamine release, which enables the update of action value via synaptic plasticity. In the second theory, neural populations integrate reward events updating action value, which is maintained in memory by a line attractor. We draw contrasting predictions and test them in theory-guided experiments using Neuropixels recordings and perturbation experiments in mice during a dynamic foraging task.
Realizado el 19 de noviembre de 2021
Idioma: Inglés
