Tics and tourette syndrome

Abstract

Gilles de la Tourette syndrome is a neurodevelopmental disorder, characterized by a wide variety of symptoms, ranging from simple motor and phonic tics to complex movement cascades, and echophenomena and coprophenomena. Moreover, Tourette syndrome is frequently accompanied by obsessive-compulsive disorder and attention-deficit hyperactivity disorder, often leading to a higher psychosocial impairment than tics. Tics are typically associated with an uncontrollable, uncomfortable, premonitory urge to execute the tic. Although Tourette syndrome is highly heritable, no single gene could be identified as a main risk factor for developing tics, yet. Moreover, the severity of Tourette syndrome can be influenced by environmental factors such as stress or attention. Pathophysiologically, Tourette syndrome has been repeatedly associated with abnormalities in cortico-striatal-thalamo-cortical loops and the dopaminergic neurotransmitter system. In accordance with these observations, successful treatment measures include neuroleptics, behavioural therapy and in severe cases tetra-hydro-cannabinol and deep brain stimulation of some of the structures in cortico-striatal-thalamo-cortical loops.