Physiological and behavioral functions of the basal ganglia

The basal ganglia are implicated in a wide range of behaviors and are particularly important for many types of learning. The diversity of basal ganglia function is tied to cortical diversity; indeed, the entire cortex outputs to the basal ganglia, which is routed in a loop via the thalamus back to the cortex. These three components of the cortex, basal ganglia, and thalamus likely form an archetypal circuit which carries out similar computations in the perceptual, cognitive, and motor domains. The way in which activity propagates across these structures, and how this propagation changes to support learning, are largely unknown. I propose to investigate the interdependence within this circuit by building on my prior work on communication between the cortex and striatum. In those experiments, I developed methodology towards defining the functional relationship between structures, and identified specific learning-induced changes. Here, I will trace those changes across structures throughout learning, I will determine how these changes affect the little-studied output arm of the basal ganglia, and I will causally determine which connections within this circuit drive specific components of both activity and learned behavior. These experiments will contribute toward a holistic understanding of a major neural circuit.