title: Differential role of dopamine in emotional attention and memory: evidence from Parkinson's disease.
abstract: Consistent with the hypothesis that dopamine is implicated in the processing of salient stimuli relevant to the modification of various behavioral responses, Parkinson's disease is associated with emotional blunting. To address the hypothesis that emotional attention and memory are modulated by dopaminergic neurotransmission in Parkinson's disease, we assessed 15 nondemented patients with Parkinson's disease while on and off dopaminergic medication and 15 age-matched healthy controls. Visual stimuli were presented, and recognition was used to assess emotional memory. Response latency was used as a measure of emotional attention modulation. Stimuli were varied based on valence (pleasant, neutral, and unpleasant) and arousal (high and low) dimensions. Controls had significantly better memory for positive than negative stimuli, whereas patients with Parkinson's disease tested off medication had significantly better memory for negative than positive items. This negativity bias was lost when they were tested while on dopaminergic medication. Reaction times in patients with Parkinson's disease off medication were longer than in healthy controls and, paradoxically, were even longer when on medication. Further, although both healthy controls and patients with Parkinson's disease in the "off" state had arousal-induced prolongation of reaction time, this effect was not seen in patients with Parkinson's disease on medication. These data indicate that dopaminergic neurotransmission is implicated in emotional memory and attention and suggest that dopamine mediates emotional memory via the valence dimension and emotional attention via arousal. Furthermore, our findings suggest that emotional changes in Parkinson's disease result from the effects of both the disease process and dopaminergic treatment.
authors.affiliation: Department of Neurology, Mount Sinai School of Medicine, New York, New York, USA. thomas.haelbig@charite.de
authors.forename: Thomas D
authors.initials: TD
authors.lastname: Hälbig
authors.forename: Stephanie
authors.initials: S
authors.lastname: Assuras
authors.forename: Judy
authors.initials: J
authors.lastname: Creighton
authors.forename: Joan C
authors.initials: JC
authors.lastname: Borod
authors.forename: Winona
authors.initials: W
authors.lastname: Tse
authors.forename: Pasquale G
authors.initials: PG
authors.lastname: Frisina
authors.forename: Andrei
authors.initials: A
authors.lastname: Voustianiouk
authors.forename: Jean-Michel
authors.initials: JM
authors.lastname: Gracies
authors.forename: C Warren
authors.initials: CW
authors.lastname: Olanow
mesh_terms: D000368:Aged; D000704:Analysis of Variance; D001288:Attention / Q000187:drug effects*; D016022:Case-Control Studies; D015259:Dopamine Agents / Q000494:pharmacology* / Q000627:therapeutic use; D004644:Emotions / Q000187:drug effects*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009483:Neuropsychological Tests; D010300:Parkinson Disease / Q000188:drug therapy / Q000503:physiopathology*; D010775:Photic Stimulation / Q000379:methods; D011930:Reaction Time; D021641:Recognition, Psychology / Q000187:drug effects*
chemical_list: D015259:Dopamine Agents