Summary
Thirty-two rats injected with 20 mg/kg amobarbital and 32 given placebo were run 96 trials on a black-white discrimination followed by 160 trials of reversal training. Trials to the discriminanda were equated to provide speed data to the nonrewarded stimulus (S−) as well as to the rewarded stimulus (S+). Half the Ss were changed in drug state at the onset of reversal. The drug did not affect choice behavior or differential start speed to S+ and S− in acquisition although speeds closer to the goal were affected. In contrast, during reversal amobarbital Ss made fewer correct choice responses when compared to placebo Ss and displayed less pronounced differential start speed responding to S+ and S−. In addition to the main drug effect, a change of drug state facilitated reversal.
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This paper is based upon a dissertation submitted to Carnegie Institute of Technology in partial fulfillment of the requirements for the Ph. D. degree. The author wishes to thank H. Wayne Ludvigson for his guidance throughout this investigation, and Herbert Barry, III, for his critical reading of the manuscript. A brief report of this experiment was presented at the Midwestern Psychological Association, April 1965.
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Caul, W.F. Effects of amobarbital on discrimination acquisition and reversal. Psychopharmacologia 11, 414–421 (1967). https://doi.org/10.1007/BF00405025
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DOI: https://doi.org/10.1007/BF00405025