Beasley Madeline M, Amantini Sarah, Gunawan Tommy, Silberberg Alan, Kearns David N
Department of Psychology, American University.
Human Psychopharmacology Laboratory, National Institute on Alcohol Abuse and Alcoholism.
Exp Clin Psychopharmacol. 2024 Apr;32(2):158-172. doi: 10.1037/pha0000674. Epub 2023 Aug 3.
The present study used a rat choice model to test how cocaine or heroin economically interacted with two different nondrug reinforcers along the substitute-to-complement continuum. In Experiment 1, the nondrug alternative was the negative reinforcer timeout-from-avoidance (TOA)-that is, rats could press a lever to obtain a period of safety from footshock. One group of rats chose between cocaine and TOA and another group chose between heroin and TOA. The relative prices of the reinforcers were manipulated across phases while controlling for potential income effects. When cocaine was the reinforcer, rats reacted to price changes by increasing their allocation of behavior to the more expensive option, thereby maintaining relatively proportional intake of cocaine and TOA reinforcers across prices, suggesting these reinforcers were complements here. In contrast, when heroin became relatively cheap, rats increased allocation of income to heroin and decreased allocation of income to TOA, suggesting that heroin substituted for safety. Additionally, rats were willing to accept more footshocks when heroin was easily available. In Experiment 2, the nondrug alternative was saccharin, a positive reinforcer. Heroin and saccharin were complements, but there was no consistent effect of price changes on the allocation of behavior between cocaine and saccharin. As a model of the processes that could be involved in human drug use, these results show that drug-taking behavior depends on the type of drug, the type of nondrug alternative available, and the prices of both. (PsycInfo Database Record (c) 2024 APA, all rights reserved).
本研究使用大鼠选择模型来测试可卡因或海洛因如何沿替代到互补的连续体与两种不同的非药物强化物进行经济上的相互作用。在实验1中，非药物选择是负性强化物——回避超时（TOA），即大鼠可以按压杠杆以获得免受电击的一段安全时间。一组大鼠在可卡因和TOA之间进行选择，另一组大鼠在海洛因和TOA之间进行选择。在控制潜在收入效应的同时，跨阶段操纵强化物的相对价格。当可卡因作为强化物时，大鼠通过增加对更昂贵选项的行为分配来对价格变化做出反应，从而在不同价格下保持可卡因和TOA强化物的摄入量相对成比例，这表明这些强化物在这里是互补的。相比之下，当海洛因变得相对便宜时，大鼠增加了对海洛因的收入分配，减少了对TOA的收入分配，这表明海洛因替代了安全。此外，当海洛因容易获得时，大鼠愿意接受更多电击。在实验2中，非药物选择是糖精，一种正性强化物。海洛因和糖精是互补的，但价格变化对可卡因和糖精之间行为分配没有一致的影响。作为可能涉及人类药物使用过程的模型，这些结果表明，吸毒行为取决于药物类型、可用的非药物选择类型以及两者的价格。（PsycInfo数据库记录（c）2024美国心理学会，保留所有权利）
