title: Brain activation during implicit sequence learning in individuals with trichotillomania.
abstract: Trichotillomania (TTM) may be related to obsessive-compulsive disorder (OCD) and other neuropsychiatric conditions characterized by cortico-striatal dysfunction. Functional imaging studies of OCD using an implicit learning task have found abnormalities in striatal and hippocampal activation. The current study investigated whether similar abnormalities occur in TTM. Functional MRI and the serial reaction time (SRT) task were used to assess striatal and hippocampal activation during implicit sequence learning in TTM and healthy control (HC) subjects. The results for 20 age- and education-matched participants (10 TTM, 10 HC) are reported. In comparison with HC participants, those with TTM exhibited no significant differences in implicit learning, or in activation within the striatum, hippocampus, or other brain regions. The current findings do not provide evidence for cortico-striatal dysfunction in TTM. Future studies directly comparing OCD and TTM subjects are warranted to confirm the specificity of abnormal striatal and hippocampal findings during implicit sequence learning in OCD.
authors.affiliation: Department of Psychiatry, Massachusetts General Hospital, Harvard Medical School, Boston, MA, USA. srauch@partners.org
authors.forename: Scott L
authors.initials: SL
authors.lastname: Rauch
authors.forename: Christopher I
authors.initials: CI
authors.lastname: Wright
authors.forename: Cary R
authors.initials: CR
authors.lastname: Savage
authors.forename: Brian
authors.initials: B
authors.lastname: Martis
authors.forename: Katherine G
authors.initials: KG
authors.lastname: McMullin
authors.forename: Michelle M
authors.initials: MM
authors.lastname: Wedig
authors.forename: Andrea L
authors.initials: AL
authors.lastname: Gold
authors.forename: Nancy J
authors.initials: NJ
authors.lastname: Keuthen
mesh_terms: D000328:Adult; D001921:Brain / Q000378:metabolism* / Q000503:physiopathology*; D003342:Corpus Striatum / Q000378:metabolism* / Q000503:physiopathology*; D005260:Female; D006624:Hippocampus / Q000378:metabolism / Q000503:physiopathology; D006801:Humans; D007858:Learning / Q000502:physiology*; D008279:Magnetic Resonance Imaging; D009771:Obsessive-Compulsive Disorder / Q000175:diagnosis / Q000453:epidemiology / Q000503:physiopathology; D011930:Reaction Time; D012720:Severity of Illness Index; D014256:Trichotillomania / Q000453:epidemiology / Q000378:metabolism* / Q000503:physiopathology*