title: Dopaminergic challenge with bromocriptine one month after mild traumatic brain injury: altered working memory and BOLD response.
abstract: Catecholamines, particularly dopamine, modulate working memory (WM). Altered sensitivity to dopamine might play a role in WM changes observed after traumatic brain injury (TBI). Thirty-one healthy controls (HC) and 26 individuals with mild TBI (MTBI) 1 month after injury were challenged with bromocriptine versus placebo before administration of a verbal WM functional MRI task. Bromocriptine was associated with improved WM performance in the HC but not the MTBI group. On bromocriptine, the MTBI group showed increased activation outside of a task-specific region of interest. Findings are consistent with the hypothesis that individuals with MTBI have altered responsivity to dopamine.
authors.affiliation: Section of Neuropsychiatry, Department of Psychiatry, Dartmouth Medical School, Lebanon, NH, USA. thomas.w.mcallister@dartmouth.edu
authors.forename: Thomas W
authors.initials: TW
authors.lastname: McAllister
authors.forename: Laura A
authors.initials: LA
authors.lastname: Flashman
authors.forename: Brenna C
authors.initials: BC
authors.lastname: McDonald
authors.forename: Richard B
authors.initials: RB
authors.lastname: Ferrell
authors.forename: Tor D
authors.initials: TD
authors.lastname: Tosteson
authors.forename: Norman N
authors.initials: NN
authors.lastname: Yanofsky
authors.forename: Margaret R
authors.initials: MR
authors.lastname: Grove
authors.forename: Andrew J
authors.initials: AJ
authors.lastname: Saykin
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000704:Analysis of Variance; D001921:Brain / Q000098:blood supply* / Q000187:drug effects*; D001930:Brain Injuries / Q000150:complications / Q000188:drug therapy; D001931:Brain Mapping; D001971:Bromocriptine / Q000627:therapeutic use*; D018592:Cross-Over Studies; D018491:Dopamine Agonists / Q000627:therapeutic use*; D004311:Double-Blind Method; D005260:Female; D006801:Humans; D007091:Image Processing, Computer-Assisted; D008279:Magnetic Resonance Imaging / Q000379:methods; D008297:Male; D008569:Memory Disorders / Q000097:blood / Q000188:drug therapy* / Q000209:etiology; D008570:Memory, Short-Term / Q000187:drug effects*; D008875:Middle Aged; D009483:Neuropsychological Tests; D010100:Oxygen / Q000097:blood; D011388:Prolactin / Q000097:blood; D055815:Young Adult
chemical_list: D018491:Dopamine Agonists; D001971:Bromocriptine; D011388:Prolactin; D010100:Oxygen