To evaluate performance on a cognitive flexibility task after administration of a dopaminergic agonist.
L-3,4-dihydroxyphenylalanine, which is converted into dopamine and norepinephrine, results in a restriction of the semantic network in priming experiments. Recent evidence suggests that flexibility of access to semantic networks in problem solving is mediated by the noradrenergic system. We wished to determine if dopaminergic agonists also affect this type of cognitive flexibility.
Eighty-four subjects were tested twice on an anagram task, once 1 hour after bromocriptine (dopamine agonist) and once 1 hour after placebo administration.
No difference was detected between placebo and bromocriptine on anagram performance.
Therefore, modulation of this type of cognitive flexibility does not seem to be mediated by the dopaminergic system. This suggests that the noradrenergic modulation of cognitive flexibility previously reported does not seem to extend to the dopaminergic system among catecholamines.
*Department of Neurology, The Ohio State University, Columbus, OH
†Department of Neurology, University of Colorado, Boulder, CO
Funded by The Roessler Scholarship from The Ohio State University (Smith) and by NIDA (DA15734) and NINDS (NS043222) (Beversdorf).
Preliminary results of this research were presented in abstract form at Society for Neuroscience, 2002.
Reprints: David Q. Beversdorf, MD, Department of Neurology, The Ohio State University, 1654 Upham Dr Room 461, Columbus, OH 43210 (e-mail: email@example.com).
Received for publication January 11, 2007; accepted October 12, 2007