This Article Full Text (PDF) References Alert me when this article is cited Alert me if a correction is posted Citation Map Services Email this article to a friend Similar articles in this journal Similar articles in ISI Web of Science Similar articles in PubMed Alert me to new issues of the journal Add to Saved Citations Download to citation manager Request Permissions Request Reprints Add to My Marked Citations Citing Articles Citing Articles via HighWire Citing Articles via ISI Web of Science (13) Citing Articles via Google Scholar Citing Articles via Scopus Google Scholar Articles by Hughes, J. H. Articles by Young, A. H. Search for Related Content PubMed PubMed Citation Articles by Hughes, J. H. Articles by Young, A. H. Social Bookmarking                   What's this?

The Effects of Acute Tryptophan Depletion on Neuropsychological Function

University of Newcastle upon Tyne, Department of Psychiatry, The Royal Victoria Infirmary, Newcastle upon Tyne, UK

Peter Gallagher

University of Newcastle Upon Tyne, Department of Psychiatry, The Royal Victoria Infirmary, Newcastle Upon Tyne, UK

Mary E. Stewart

University of Newcastle Upon Tyne, Department of Psychiatry, The Royal Victoria Infirmary, Newcastle upon Tyne, UK

David Matthews

University of Newcastle Upon Tyne, Department of Psychiatry, The Royal Victoria Infirmary, Newcastle Upon Tyne, UK

Tom P. Kelly

University of Newcastle Upon Tyne, Department of Psychiatry, The Royal Victoria Infirmary, Newcastle Upon Tyne, UK

Allan H. Young

University of Newcastle Upon Tyne, Department of Psychiatry, The Royal Victoria Infirmary, Newcastle Upon Tyne, UK, a.h.young{at}ncl.ac.uk

Serotonin (5-HT, 5-hydroxytryptamine) may have an important role in the maintenance of normal neuropsychological functioning. The method of acute tryptophan depletion (ATD) provides a pharmacological challenge by which central 5-HT levels can be temporarily decreased and effects on learning, memory and mood examined. Twenty healthy male volunteers were recruited to take part in this within-subject, double-blind, crossover study. Neuropsychological function was evaluated 4-6 h after ingestion of a control or 52 g tryptophan (TRP) depleting amino-acid drink. ATD significantly lowered levels of plasma total and free TRP (p < 0.001), but this did not affect mood or performance on tests of verbal and visuo-spatial learning and memory, attention or executive function. These results contradict previous findings; however, the degree of disruption of central 5-HT levels resulting from the use of the 52 g amino-acid protocol may be an important factor in explaining the lack of effect. By utilizing more specific probes of individual 5-HT receptor subtypes, future studies can fully explore the role of 5-HT in neuropsychological functioning and may elucidate the factors determining vulnerability to the effects of serotonergic dysfunction.

Key Words: acute tryptophan depletion • attention • CANTAB • learning • memory • mood • serotonin

Journal of Psychopharmacology, Vol. 17, No. 3, 300-309 (2003)
DOI: 10.1177/02698811030173012


CiteULike    Connotea    Del.icio.us    Digg    Reddit    Technorati    What's this?

This article has been cited by other articles:

				A. Sambeth, W. Riedel, D. Tillie, A. Blokland, A. Postma, and J. Schmitt Memory impairments in humans after acute tryptophan depletion using a novel gelatin-based protein drink J Psychopharmacol, January 1, 2009; 23(1): 56 - 64. [Abstract] [PDF]

				M. Wingen, K.P.C. Kuypers, and J.G. Ramaekers Selective verbal and spatial memory impairment after 5-HT1A and 5-HT2A receptor blockade in healthy volunteers pre-treated with an SSRI J Psychopharmacol, July 1, 2007; 21(5): 477 - 485. [Abstract] [PDF]

				H. F. Clarke, S. C. Walker, H. S. Crofts, J. W. Dalley, T. W. Robbins, and A. C. Roberts Prefrontal Serotonin Depletion Affects Reversal Learning But Not Attentional Set Shifting J. Neurosci., January 12, 2005; 25(2): 532 - 538. [Abstract] [Full Text] [PDF]