Abstract
Thirty-two male albino rats were trained on a black-white discrimination for water reward. Forty-eight hours later, half were tested for memory of the task and the other half trained on a reversal. Subjects received α-methyltyrosine (α-MT), an inhibitor of catecholamine (CA) biosynthesis, by multiple i.p. injections of 50 mg/kg, before the training session, before the testing or reversal, before both, or before neither. Data analysis showed that drugged rats learned the black-white discrimination in fewer trials (p<0.0005), but had longer latencies (p<0.0005). These data are contrasted to α-MT depression of the conditioned avoidance response (CAR), and the difference attributed to the role of CA in motor ability and in attention.
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Saper, C.B., Sweeney, D.C. Enhanced appetitive discrimination learning in rats treated with α-methyltyrosine. Psychopharmacologia 30, 37–44 (1973). https://doi.org/10.1007/BF00422792
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DOI: https://doi.org/10.1007/BF00422792