Acute dopamine and/or serotonin depletion does not modulate mismatch negativity (MMN) in healthy human participants.
BACKGROUND
Schizophrenia is commonly associated with impairments in pre-attentive change detection, as represented by reduced mismatch negativity (MMN). While the neurochemical basis of MMN has been linked to N-methyl-D: -aspartic acid (NMDA) receptor function, the roles of the dopaminergic and/or the serotonergic systems are not fully explored in humans.


OBJECTIVE
The aim of the present study was to investigate the effects of acutely depleting dopamine (DA) and serotonin (5-hydroxytryptamine, 5-HT) alone or simultaneously by depleting their amino acid precursors on MMN in healthy participants.


METHODS
Sixteen healthy male subjects participated in a double-blind, placebo-controlled, cross-over design in which each subject's duration MMN was assessed under four acute treatment conditions separated by a 5-day washout period: balanced amino acid control (no depletion), tyrosine/phenylalanine depletion (to reduce DA neurotransmission), tryptophan depletion (to reduce 5-HT neurotransmission) and tryptophan/tyrosine/phenylalanine depletion (to reduce DA and 5-HT neurotransmission simultaneously).


RESULTS
Acute depletion of either DA and 5-HT alone or simultaneously had no effect on MMN.


CONCLUSIONS
These findings suggest that modulation of the dopaminergic and serotonergic systems acutely does not lead to changes in MMN.
Leung
Sumie
S
Brain Sciences Institute, Faculty of Life and Social Sciences, Swinburne University of Technology, P.O. Box 218, John Street Hawthorn, 3122, Melbourne, VIC, Australia. smleung@groupwise.swin.edu.au
Croft
Rodney J
RJ
Guille
Valérie
V
Scholes
Kirsty
K
O'Neill
Barry V
BV
Phan
K Luan
KL
Nathan
Pradeep J
PJ
D000328:Adult; D003265:Contingent Negative Variation; D018592:Cross-Over Studies; D004298:Dopamine / Q000172:deficiency*; D004311:Double-Blind Method; D004569:Electroencephalography; D006801:Humans; D008297:Male; D009434:Neural Pathways / Q000378:metabolism*; D010649:Phenylalanine / Q000172:deficiency; D011930:Reaction Time; D012701:Serotonin / Q000172:deficiency*; D013997:Time Factors; D014364:Tryptophan / Q000172:deficiency; D014443:Tyrosine / Q000172:deficiency; D055815:Young Adult
D012701:Serotonin; D014443:Tyrosine; D010649:Phenylalanine; D014364:Tryptophan; D004298:Dopamine