Behavioral flexibility in the corticostriatal network
- Author(s): Kondapavulur, Sravani
- Advisor(s): Ganguly, Karunesh
- et al.
A critical question in skilled motor control is how brain circuits can flexibly apply learned motor behaviors to novel contexts. Plasticity in the corticostriatal network has been historically been implicated in motor learning across different species. In particular, the motor cortex and striatum are monosynaptically connected structures that play critical roles in early motor learning as well as consolidation of crystallized motor skills. However, when a welllearned skill must adapt to a new context, how does neural activity in these important motor regions support the behavioral transition?
This thesis begins by providing a perspective on how motor learning, adaptation, and habit formation have been classically studied, in addition to the current understanding of neural bases for each of these processes. I then outline the implications of motor task selection and behavioral intervention when making conclusions about underlying neural mechanisms. In Chapter 2, I present my work investigating how the corticostriatal network supports transfer learning of a previously acquired complex coordinated upper limb action, demonstrating that relearning in a new context involves partial breakdown of previously crystallized neural activity. I conclude by presenting in Chapter 3 a model for network control of motor flexibility, proposing that cortico-striatal activity reflects dynamic optimization of neural patterns, adapting upstream cognitive contributions and driving existing downstream circuits for movement generation. Finally, I explore the implications of corticostriatal dysfunction in motor diseases.