Real action, language, and thought occur in streams of complex sequential patterns, a shared feature named action syntax . The brain neostriatum and related structures such as substantia nigra are thought to help control the sequential pattern of normal human language and thought, and nigrostriatal dysfunction is linked to obsessive-compulsive disorder, Tourette's syndrome, and Parkinson's disease. Human language/thought sequencing functions of the striatum derive from its evolutionary role in sequencing instinctive actions, including rodent grooming.

Our studies show that the brain neostriatum controls the sequential pattern of instinctive grooming behaviors. We are also examining how firing of neurons in neostriatum and connected brain structures actually codes sequential patterns, in collaborative electrophysiology studies with the laboratory of Dr. J. Wayne Aldridge. Our goal is to better understand the brain link that connects animal instinctive actions to human language and thought (Overview ).