Abstract:

Some actions are innate or prewired (such as swallowing or breathing).

Others are learned anew throughout life, likely through a process of trial and feedback. We used electrophysiology, imaging and optogenetics in behaving animals to understand how novel self-paced actions are generated, and how specific actions that lead to particular outcomes are then selected. We uncovered that dopamine is critical for the initiation of novel actions, and that plasticity in cortico-basal ganglia circuits is necessary for action selection. Furthermore, as actions are shaped they become organized into chunks, and neural substrates of parsing and concatenation of motor chunks emerge in basal ganglia circuits.