Serotonin levels influence patterns of repetition priming.
Repetition priming in a word-stem completion task was examined in a group of control subjects and in a group of experimental subjects under conditions of acute tryptophan depletion (T-) and tryptophan augmentation (T+). Experimental subjects ingested amino acid compounds that depleted or loaded the body with tryptophan, and word-stem completion priming performance was measured. Results indicate differential effects of T- and T+ manipulations on word-stem completion priming. In the control group, both specific-visual and amodal priming were observed. Conversely, in the T+ condition, specific-visual priming, but no amodal priming, was observed, whereas in the T- condition, amodal priming, but no specific-visual priming, was observed. The authors conclude that serotonin (5-hydroxytryptamine) plays a critical role in repetition priming by helping to modulate which neural systems contribute to priming effects.
Burgund
E Darcy
ED
Department of Neurology, Washington University School of Medicine, St. Louis, Missouri 63110, USA. darcy@npg.wustl.edu
Marsolek
Chad J
CJ
Luciana
Monica
M
D000293:Adolescent; D000328:Adult; D001307:Auditory Perception / Q000502:physiology; D001921:Brain / Q000502:physiology; D005260:Female; D006801:Humans; D006854:Hydrocortisone / Q000097:blood; D008297:Male; D011939:Mental Recall / Q000502:physiology*; D009483:Neuropsychological Tests; D010153:Paired-Associate Learning / Q000502:physiology*; D010364:Pattern Recognition, Visual / Q000502:physiology; D011214:Practice, Psychological; D011388:Prolactin / Q000097:blood; D011932:Reading; D012701:Serotonin / Q000502:physiology*; D014364:Tryptophan / Q000008:administration & dosage / Q000172:deficiency; D014706:Verbal Learning / Q000502:physiology*
D012701:Serotonin; D014364:Tryptophan; D011388:Prolactin; D006854:Hydrocortisone