Tics and Tourette's: update on pathophysiology and tic control.

Abstract

To describe recent advances in the pathophysiology of tics and Tourette syndrome, and novel insights on tic control. The cortico-basal ganglia-thalamo-cortical loops are implicated in generation of tics. Disruption of GABAergic inhibition lies at the core of tic pathophysiology, but novel animal models also implicate cholinergic and histaminergic neurotransmission. Tourette syndrome patients have altered awareness of volition and enhanced formation of habits. Premonitory urges are not the driving force behind all tics. The intensity of premonitory urges depends on patients' capacity to perceive interoceptive signals. The insular cortex is a key structure in this process. The trait intensity of premonitory urges is not a prerequisite of voluntary tic inhibition, a distinct form of motor control. Voluntary tic inhibition is most efficient in the body parts that tic the least. The prefrontal cortex is associated with the capacity to inhibit tics. The management of tics includes behavioral, pharmacological and surgical interventions. Treatment recommendations differ based on patients' age. The study of Tourette syndrome pathophysiology involves different neural disciplines and provides novel, exciting insights of brain function in health and disease. These in turn provide the basis for innovative treatment approaches of tics and their associations.