Moerschbaecher J M, Thompson D M, Thomas J R
J Exp Anal Behav. 1979 Sep;32(2):255-63. doi: 10.1901/jeab.1979.32-255.
Methamphetamine and scopolamine were studied in monkeys responding under a multiple fixed-ratio fixed-interval schedule of reinforcement. A response on any one of six levers could satisfy the schedule requirements. Variability of response location was evaluated in terms of switches, where a switch was defined as a response on one lever followed by a response on a different lever. Under baseline conditions the fixed-ratio schedule generated a high rate of responding and a low level of variability, while the fixed-interval schedule generated a low rate of responding and a high level of variability. Both methamphetamine (0.1 to 0.5 mg/kg) and scopolamine (2.4 to 240 microgram/kg) decreased overall response rate and increased variability of response location in each component of the multiple schedule with increasing doses of drug. At lower doses both drugs were found to decrease rate without affecting response variability.
在猴子按照多重固定比率-固定间隔强化程序做出反应的情况下，对甲基苯丙胺和东莨菪碱进行了研究。在六个杠杆中的任何一个上做出反应都可以满足程序要求。反应位置的变异性通过转换来评估，其中一次转换被定义为在一个杠杆上做出反应后紧接着在另一个不同的杠杆上做出反应。在基线条件下，固定比率程序产生高反应率和低变异性水平，而固定间隔程序产生低反应率和高变异性水平。随着药物剂量增加，甲基苯丙胺（0.1至0.5毫克/千克）和东莨菪碱（2.4至240微克/千克）均降低了多重程序各部分的总体反应率，并增加了反应位置的变异性。在较低剂量下，发现两种药物均降低反应率但不影响反应变异性。
