Effects of MK-801 on vicarious trial-and-error and reversal of olfactory discrimination learning in weanling rats.
The effects of dizocilpine maleate (MK-801) on vicarious trial-and-error (VTE), and on simultaneous olfactory discrimination learning and its reversal, were observed in weanling rats. The term VTE was used by Tolman (The determiners of behavior at a choice point. Psychol. Rev. 1938;46:318-336), who described it as conflict-like behavior at a choice-point in simultaneous discrimination learning. It takes the form of head movements from one stimulus to the other, and has recently been proposed by Amsel (Hippocampal function in the rat: cognitive mapping or vicarious trial-and-error? Hippocampus, 1993;3:251-256) as related to hippocampal, nonspatial function during this learning. Weanling male rats received systemic MK-801 either 30 min before the onset of olfactory discrimination training and its reversal, or only before its reversal. The MK-801-treated animals needed significantly more sessions to acquire the discrimination and showed significantly fewer VTEs in the acquisition phase of learning. Impaired reversal learning was shown only when MK-801 was administered during the reversal-learning phase, itself, and not when it was administered throughout both phases.
Griesbach
G S
GS
Department of Psychology and Institute for Neuroscience, University of Texas at Austin, 78712, USA.
Hu
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D
Amsel
A
A
D000818:Animals; D004193:Discrimination Learning / Q000187:drug effects*; D004192:Discrimination, Psychological / Q000187:drug effects; D016291:Dizocilpine Maleate / Q000494:pharmacology*; D018691:Excitatory Amino Acid Antagonists / Q000494:pharmacology*; D008297:Male; D010056:Overlearning / Q000187:drug effects; D011597:Psychomotor Performance / Q000187:drug effects; D051381:Rats; D017207:Rats, Sprague-Dawley; D012193:Reversal Learning / Q000187:drug effects*; D012903:Smell / Q000187:drug effects*
D018691:Excitatory Amino Acid Antagonists; D016291:Dizocilpine Maleate