Tryptophan depletion alters the decision-making of healthy volunteers through altered processing of reward cues.

@article{citeulike:1095073, abstract = {While accumulating evidence suggests that effective real-life decision-making depends upon the functioning of the orbitofrontal cortex, much less is known about the involvement of the monoamine neurotransmitter systems and, in particular, serotonin. In the present study, we explored the impact of depleting the serotonin precursor, tryptophan, on human decision-making. Eighteen healthy volunteers consumed an amino-acid drink containing tryptophan and 18 healthy volunteers consumed an amino-acid drink without tryptophan, before choosing between simultaneously presented gambles, differing in the magnitude of expected gains (ie reward), the magnitude of expected losses (ie punishment), and the probabilities with which these outcomes were delivered. Volunteers also chose between gambles probing identified non-nomative biases in human decision-making, namely, risk-aversion when choosing between gains and risk-seeking when choosing between losses. Tryptophan-depleted volunteers showed reduced discrimination between magnitudes of expected gains associated with different choices. There was little evidence that tryptophan depletion was associated with altered discrimination between the magnitudes of expected losses, or altered discrimination between the relative probabilities with which these positive or negative outcomes were delivered. Risk-averse and risk-seeking biases were also unchanged. These results suggest that serotonin mediates decision-making in healthy volunteers by modulating the processing of reward cues, perhaps represented within the orbitofrontal cortex. It is possible that such a change in the cognition mediating human choice is one mechanism associated with the onset and maintenance of anhedonia and lowered mood in psychiatric illness.}, address = {University Department of Psychiatry, University of Oxford, UK. robert.rogers@psych.ox.ac.uk}, author = {Rogers, R. D. and Tunbridge, E. M. and Bhagwagar, Z. and Drevets, W. C. and Sahakian, B. J. and Carter, C. S. }, citeulike-article-id = {1095073}, doi = {http://dx.doi.org/10.1038/sj.npp.1300001}, issn = {0893-133X}, journal = {Neuropsychopharmacology}, keywords = {behavior, decision-making, reward, tryptophan\_depletion}, month = {January}, number = {1}, pages = {153--162}, posted-at = {2007-05-18 16:48:24}, priority = {2}, title = {Tryptophan depletion alters the decision-making of healthy volunteers through altered processing of reward cues.}, url = {http://dx.doi.org/10.1038/sj.npp.1300001}, volume = {28}, year = {2003} }

TY - JOUR ID - citeulike:1095073 L3 - citeulike-article-id:1095073 TI - Tryptophan depletion alters the decision-making of healthy volunteers through altered processing of reward cues. JF - Neuropsychopharmacology VL - 28 IS - 1 SP - 153 EP - 162 AD - University Department of Psychiatry, University of Oxford, UK. robert.rogers@psych.ox.ac.uk SN - 0893-133X N2 - While accumulating evidence suggests that effective real-life decision-making depends upon the functioning of the orbitofrontal cortex, much less is known about the involvement of the monoamine neurotransmitter systems and, in particular, serotonin. In the present study, we explored the impact of depleting the serotonin precursor, tryptophan, on human decision-making. Eighteen healthy volunteers consumed an amino-acid drink containing tryptophan and 18 healthy volunteers consumed an amino-acid drink without tryptophan, before choosing between simultaneously presented gambles, differing in the magnitude of expected gains (ie reward), the magnitude of expected losses (ie punishment), and the probabilities with which these outcomes were delivered. Volunteers also chose between gambles probing identified non-nomative biases in human decision-making, namely, risk-aversion when choosing between gains and risk-seeking when choosing between losses. Tryptophan-depleted volunteers showed reduced discrimination between magnitudes of expected gains associated with different choices. There was little evidence that tryptophan depletion was associated with altered discrimination between the magnitudes of expected losses, or altered discrimination between the relative probabilities with which these positive or negative outcomes were delivered. Risk-averse and risk-seeking biases were also unchanged. These results suggest that serotonin mediates decision-making in healthy volunteers by modulating the processing of reward cues, perhaps represented within the orbitofrontal cortex. It is possible that such a change in the cognition mediating human choice is one mechanism associated with the onset and maintenance of anhedonia and lowered mood in psychiatric illness. KW - behavior KW - decision-making KW - reward KW - tryptophan_depletion AU - Rogers, RD AU - Tunbridge, EM AU - Bhagwagar, Z AU - Drevets, WC AU - Sahakian, BJ AU - Carter, CS PY - 2003/01// UR - http://dx.doi.org/10.1038/sj.npp.1300001 ER -