Circuit mechanisms of sensorimotor learning in the cortico-basal ganglia-thalamocortical network

Basal ganglia are essential for learning and adapting movements, yet their output is often unnecessary for executing learned actions. A biologically grounded model of the closed cortico-basal ganglia-thalamocortical loop explains this apparent discrepancy. Dopamine-dependent plasticity, recurrent cortical dynamics and basal ganglia feedback jointly support early motor acquisition and adaptation, shaping cortical activity even when basal ganglia output is no longer directly required. Parallel loops form functional channels for particular motor outputs. Neural recordings during zebra finch song learning provide evidence for these proposed circuit mechanisms.