Neuroimaging Studies in Tourette Syndrome

Abstract

ABSTRACTTourette syndrome (TS) is a complex neurobehavioral disorder principally characterized by motor and vocal tics. However, features of obsessive-compulsive and attention-deficit/hyperactivity disorders are often present. The basal ganglia and associated brain structures have been implicated in the pathophysiology of TS, as well as in these related conditions. Specifically, it is believed that the neuroanatomically and functionally defined basal ganglia thalamocortical loops are involved in TS. These loops are composed of a sequence of connections originating in the cortex and passing in series through the striatum (caudate and putamen), globus pallidus, and thalamus before returning to the cortical areas of origin. This review concentrates on the neuroimaging findings in Ts, particularly as they relate to alterations in components of the basal ganglia thalamocortical circuits. These neuroimaging data suggest that the major abnormalities in TS involve striatal or cortical dysfunction, as well as dysfunction of dopaminergic systems that regulate basas ganglia neurotransmission.