Dopaminergic modulation of semantic network activation.
In order to examine the effect of dopamine on semantic processing, we performed a double-blind, placebo-controlled study. Healthy volunteers (n = 31) were tested in a lexical decision paradigm after ingestion of either L-dopa 100 mg with benserazide 25 mg or placebo. While direct semantic priming was influenced only marginally by L-dopa, the indirect priming effects was reduced significantly. These data support the hypothesis that dopamine increases the signal-to-noise ratio in semantic networks by reducing the spread of semantic processing, thereby leading to a focussing of activation.
Kischka
U
U
Department of Neurology, University of Magdeburg, Germany.
Kammer
T
T
Maier
S
S
Weisbrod
M
M
Thimm
M
M
Spitzer
M
M
D000328:Adult; D001545:Benserazide / Q000494:pharmacology; D002540:Cerebral Cortex / Q000187:drug effects / Q000502:physiology; D004298:Dopamine / Q000502:physiology*; D004311:Double-Blind Method; D005260:Female; D006801:Humans; D007980:Levodopa / Q000494:pharmacology; D008297:Male; D011939:Mental Recall / Q000187:drug effects / Q000502:physiology; D009415:Nerve Net / Q000187:drug effects / Q000502:physiology*; D010153:Paired-Associate Learning / Q000187:drug effects / Q000502:physiology*; D011954:Receptors, Dopamine / Q000187:drug effects / Q000502:physiology*; D012660:Semantics
D011954:Receptors, Dopamine; D007980:Levodopa; D001545:Benserazide; D004298:Dopamine