title: Chronic dopaminergic stimulation in Parkinson's disease: from dyskinesias to impulse control disorders.
abstract: Dopamine is an essential neurotransmitter for many brain functions, and its dysfunction has been implicated in both neurological and psychiatric disorders. Parkinson's disease is an archetypal disorder of dopamine dysfunction characterised by motor, cognitive, behavioural, and autonomic symptoms. While effective for motor symptoms, dopamine replacement therapy is associated not only with motor side-effects, such as levodopa-induced dyskinesia, but also behavioural side-effects such as impulse control disorders (eg, pathological gambling and shopping, binge eating, and hypersexuality), punding (ie, abnormal repetitive non-goal oriented behaviours), and compulsive medication use. We review clinical features, overlapping molecular mechanisms, and a specific cognitive mechanism of habit learning that might underlie these behaviours. We integrate these mechanisms with the emerging view of the basal ganglia as a distributive system involved in the selection and facilitation of movements, acts, and emotions.
authors.affiliation: Wellcome Trust Centre for Neuroimaging, Institute of Neurology, University College London, London, UK. voonval@gmail.com
authors.forename: Valerie
authors.initials: V
authors.lastname: Voon
authors.forename: Pierre-Olivier
authors.initials: PO
authors.lastname: Fernagut
authors.forename: Jeff
authors.initials: J
authors.lastname: Wickens
authors.forename: Christelle
authors.initials: C
authors.lastname: Baunez
authors.forename: Manuel
authors.initials: M
authors.lastname: Rodriguez
authors.forename: Nancy
authors.initials: N
authors.lastname: Pavon
authors.forename: Jorge L
authors.initials: JL
authors.lastname: Juncos
authors.forename: José A
authors.initials: JA
authors.lastname: Obeso
authors.forename: Erwan
authors.initials: E
authors.lastname: Bezard
mesh_terms: D000978:Antiparkinson Agents / Q000009:adverse effects* / Q000627:therapeutic use; D001332:Automatism / Q000503:physiopathology; D003192:Compulsive Behavior / Q000139:chemically induced / Q000523:psychology; D007174:Disruptive, Impulse Control, and Conduct Disorders / Q000139:chemically induced* / Q000503:physiopathology; D004298:Dopamine / Q000502:physiology*; D015259:Dopamine Agents / Q000009:adverse effects* / Q000627:therapeutic use; D004409:Dyskinesia, Drug-Induced / Q000503:physiopathology*; D005715:Gambling / Q000523:psychology; D006801:Humans; D007980:Levodopa / Q000009:adverse effects* / Q000627:therapeutic use; D010300:Parkinson Disease / Q000150:complications* / Q000188:drug therapy / Q000523:psychology; D011605:Psychoses, Substance-Induced / Q000523:psychology; D012725:Sexual Behavior
chemical_list: D000978:Antiparkinson Agents; D015259:Dopamine Agents; D007980:Levodopa; D004298:Dopamine