title: Tourette's and comorbid syndromes: obsessive compulsive and attention deficit hyperactivity disorder. A common etiology?
abstract: Tourette's syndrome (TS), a neuropsychiatric movement disorder that manifests itself in childhood, is often associated with comorbid symptomatology, such as obsessions, compulsions, hyperactivity, distractibility, and impulsivity. Epidemiological studies suggest that a substantial number of TS patients develop clinical levels of obsessive-compulsive disorder (OCD) and/or attention deficit hyperactivity disorder (ADHD). This review aims to provide an integrated account of the three disorders in terms of their comorbidity. Neuroimaging studies suggest that all three disorders involve neuropathology of the basal-ganglia thalamocortical (BGTC) pathways: TS in the sensorimotor and limbic BGTC circuits; OCD in the prefrontal and limbic BGTC pathways; and ADHD in the sensorimotor, orbitofrontal, and limbic BGTC circuits. The pattern of comorbidity and other evidence indicates that the TS gene(s) may be responsible for a spectrum of disorders, including OCD and ADHD, but also that the disorders OCD and ADHD can exist in their own right with their own etiologies.
authors.affiliation: Psychology Department, Monash University, Clayton, Victoria, Australia.
authors.forename: D M
authors.initials: DM
authors.lastname: Sheppard
authors.forename: J L
authors.initials: JL
authors.lastname: Bradshaw
authors.forename: R
authors.initials: R
authors.lastname: Purcell
authors.forename: C
authors.initials: C
authors.lastname: Pantelis
mesh_terms: D001289:Attention Deficit Disorder with Hyperactivity / Q000209:etiology* / Q000473:pathology / Q000503:physiopathology; D001921:Brain / Q000000981:diagnostic imaging / Q000378:metabolism / Q000473:pathology; D006801:Humans; D009415:Nerve Net / Q000503:physiopathology*; D009771:Obsessive-Compulsive Disorder / Q000209:etiology* / Q000473:pathology / Q000503:physiopathology; D011859:Radiography; D011877:Radionuclide Imaging; D005879:Tourette Syndrome / Q000209:etiology* / Q000473:pathology / Q000503:physiopathology