Speaker: Allison Hamilos

Affiliation: Whitehead Fellow, Whitehead Institute, MIT

Title: Linking learning and movement initiation

Abstract: The question of what dopamine represents has sparked spirited debate, with much attention devoted to understanding how reward-related dopaminergic signals may be involved in learning, potentially via the update of cortico-striatal synaptic weights. Yet, human movement disorders have long suggested that dopamine can also have “real-time” effects on behavior. It remains mysterious how and in what settings dopamine serves each of these roles, as well as how it exerts these effects through its interactions with downstream neural circuitry. We recently demonstrated a causal, real-time effect of dopamine in the context of a self-timing game, where the ongoing activity of dopamine neurons modulates the moment-to-moment probability of initiating movement. Given this game also elicits reward-related dopaminergic signals, this paradigm presents an opportunity to examine both movement-timing and (potential) learning signals within the same task, allowing us to dissect how dopamine neurons and their downstream neural circuit partners participate in both processes. In this talk, I will present new results from mice and humans playing this game, which suggest an unexpected, trial-by-trial learning effect of dopaminergic signaling that shapes an apparent probabilistic generative process for initiating movement in the near future.

Location: 46-3310

Zoom: https://mit.zoom.us/j/3473065359