Differential kinematic coding in sensorimotor striatum across species-typical and learned behaviors reflects a difference in control

The sensorimotor arm of the basal ganglia is a major part of the mammalian motor control network, yet whether it is essential for generating natural behaviors or specialized for learning and controlling motor skills is unclear. We examine this by contrasting contributions of the sensorimotor striatum (rodent dorsolateral striatum, DLS) to spontaneously expressed species-typical behaviors versus those adapted for a task. In stark contrast to earlier work implicating DLS in the control of acquired skills, bilateral lesions had no discernable effects on the expression or detailed kinematics of species-typical behaviors, such as grooming, rearing, or walking. To probe the neural correlates underlying this dissociation, we compared DLS activity across the behavioral domains. While neural activity reflected the kinematics of both learned and species-typical behaviors, the coding schemes were very different. Taken together, we did not find evidence for the basal ganglia circuit being required for species-typical behaviors; rather, our results suggest that it monitors ongoing movement and learns to alter its output to shape skilled behaviors in adaptive and task-specific ways.