The basal ganglia and the cerebellum are two crucial areas in the central nervous system which are connected together to form an integrated functional network according to researchers at the University of Pittsburgh.
Each subcortical structure houses a unique learning mechanism.
It is believed that the basal ganglia circuits are involved in reward-driven learning and the gradual formation of habits.
On the other hand, cerebellar circuits are thought to contribute to more rapid and plastic learning in response to errors in performance.
"The basal ganglia and the cerebellum are two major subcortical structures that receive input from and send output to the cerebral cortex to influence movement and cognition," explained senior author Dr. Peter L. Strick, professor of neurobiology and co-director of the Center for the Neural Basis of Cognition, Pitt School of Medicine.
"In the past, these two learning mechanisms were viewed as entirely separate, and we wondered how signals from the two were integrated. Using a unique method for revealing chains of synaptically linked neurons, we have demonstrated that the cerebellum and basal ganglia are actually interconnected and communicate with each other," said Strick.
The finding not only has important implications for the normal control of movement and cognition, but it also helps to explain some puzzling findings from patients with basal ganglia disorders.
"Our findings provide a neural basis for these findings. In essence, the pathways that we have discovered may enable abnormal signals from the basal ganglia to disrupt cerebellar function. The alterations in cerebellar function are likely to contribute to the disabling symptoms of basal ganglia disorders. Thus, a new approach for treating these symptoms might be to attempt to normalize cerebellar activity," said Strick.
The findings are available online this week in the Proceedings of the National Academy of Sciences.