Tomie A, Mosakowski E M
Dept. of Psychology, Rutgers University, New Brunswick, NJ 08903, USA.
Pharmacol Biochem Behav. 1996 Aug;54(4):699-703. doi: 10.1016/0091-3057(96)00022-6.
Female Long-Evans rats were trained to discriminate d-amphetamine (0.8 mg/kg) vs. saline in a food-reinforced two-lever operant task. Fifteen rats (fast group) acquired the discrimination rapidly, achieving criterion (eight correct choices within ten sessions) during the first 10 sessions (mean sessions to criterion = 10.0). The remaining eight rats (slow group) made at least three errors during the first 10 sessions and required additional drug discrimination training to achieve criterion (mean sessions to criterion = 15.9). When a rat had completed a minimum of 30 two-lever discrimination training sessions and, in addition, provided 10 correct choices within 10 sessions, generalization testing with lower doses of d-amphetamine was initiated. The fast group made more d-amphetamine-appropriate choices during the generalization test and generalized more to the 0.2 mg/kg d-amphetamine test dose than did the slow group, though the number of training sessions prior to generalization testing was comparable across groups. Results suggest that when the training drug is easily discriminated, fast learners generalize more, even when groups receive comparable amounts of training prior to generalization testing, and this effect is observed in female rats.
雌性Long-Evans大鼠接受训练，在食物强化的双杠杆操作性任务中区分d-苯丙胺（0.8毫克/千克）和生理盐水。15只大鼠（快速组）迅速掌握了辨别能力，在前10个训练阶段达到了标准（10个训练阶段内有8次正确选择）（达到标准的平均训练阶段数 = 10.0）。其余8只大鼠（慢速组）在前10个训练阶段至少犯了3次错误，需要额外的药物辨别训练才能达到标准（达到标准的平均训练阶段数 = 15.9）。当一只大鼠完成至少30次双杠杆辨别训练阶段，并且此外在10个训练阶段内做出10次正确选择时，就开始用较低剂量的d-苯丙胺进行泛化测试。在泛化测试中，快速组做出的与d-苯丙胺相符的选择更多，并且与慢速组相比，对0.2毫克/千克d-苯丙胺测试剂量的泛化程度更高，尽管在泛化测试之前两组的训练阶段数相当。结果表明，当训练药物易于辨别时，快速学习者的泛化程度更高，即使在泛化测试之前各组接受的训练量相当，并且这种效应在雌性大鼠中也能观察到。
