[The neurobiological bases of obsessive-compulsive disorder and Tourette syndrome].

OBJECTIVE To describe and discuss evidence-based articles on the neurobiology of obsessive-compulsive disorder and Tourette syndrome. SOURCES OF DATA A review of the most relevant papers on the phenomenology, neuroanatomy, neuroimaging, genetic and immunological aspects of these two disorders was performed. SUMMARY OF THE FINDINGS Ritualistic behaviors and repetitive thoughts have been extensively studied in the last years. The definitions of obsessive-compulsive disorder and Tourette syndrome emphasize the existence of a continuum of symptoms, with high prevalence in the general population. Neurobiological findings have implicated genetic and immunological factors in the etiology of these two disorders. CONCLUSIONS Advances in neuroscience triggered genetic and immunological research studies, allowing new perspectives on the treatment of obsessive-compulsive disorder and Tourette syndrome patients.