Johanson C E
Psychopharmacology (Berl). 1977 Aug 16;53(3):277-82. doi: 10.1007/BF00492364.
A choice procedure was used to determine the ability of electric shock to suppress cocaine-maintained responding in a situation where cocaine was also available on a second lever without shock. In each session rhesus monkeys were allowed to self-inject cocaine five times in the presence of a stimulus. Thirty minutes after the fifth injection a second dose of cocaine could be self-injected five times in the presence of a different stimulus. At the onset of the injection of this dose a 5 or 10 mA electric shock was delivered. Thirty minutes later choice trials began in which both stimuli were present and monkeys could choose one of the two doses of cocaine. Electric shock was delivered at the onset of the injection of one of these alternatives. Initially, both doses of cocaine were 0.1 mg/kg. The dose of cocaine associated with electric shock was systematically increased until it was preferred to the dose not associated with electric shock. The results indicate that although responding maintained by cocaine can be suppressed by punishment, this effect can be attenuated by increasing magnitude of reinforcement.
采用一种选择程序来确定电击在可卡因也可在无电击的第二个杠杆上获取的情况下抑制可卡因维持反应的能力。在每个实验阶段，恒河猴被允许在一种刺激存在的情况下自我注射可卡因五次。在第五次注射后30分钟，可在另一种不同刺激存在的情况下自我注射第二剂可卡因五次。在注射该剂量时开始施加5或10毫安的电击。30分钟后开始选择试验，此时两种刺激都存在，猴子可以选择两种可卡因剂量中的一种。在注射其中一种选择的药物时开始施加电击。最初，两种可卡因剂量均为0.1毫克/千克。与电击相关的可卡因剂量被系统地增加，直到它比与电击无关的剂量更受偏爱。结果表明，虽然可卡因维持的反应可以通过惩罚来抑制，但这种效应可以通过增加强化强度来减弱。
