Lancaster J S, Dallery J
Department of Psychology, Morris Brown College, Atlanta, Georgia, USA.
Behav Pharmacol. 1999 Jul;10(4):337-47. doi: 10.1097/00008877-199907000-00001.
The study was designed to integrate rate-related principles and Herrnstein's hyperbolic matching equation (1970) as they apply to drug effects. It was also designed to assess the validity of an interpretation of Herrnstein's equation used to account for the behavioral mechanisms of drug action. Eight rats were trained to press a lever under a range of variable-interval (VI) schedules of reinforcement using sucrose solution (0.1 M) as a reinforcer. After 90 baseline sessions the effect of morphine sulfate, 3, 6, 12 and 17 mg/kg, on responding was tested. Response rates were suppressed in a dose-dependent manner after morphine administration. Herrnstein's equation, which states that responding is a function of relative reinforcement rate, provided a good description of the relationship between responding and reinforcement under most conditions. Therefore, the traditional variable used to predict the drug effect in rate-dependency functions, baseline response rate, was compared to a new variable, baseline relative reinforcement rate. Relative reinforcement rate performed as well as response rate in predicting the drug effect. In order to test if Herrnstein's hyperbola can identify the behavioral mechanisms of the action of morphine, the concentration of the sucrose solution was increased (0.32 M). The y-asymptote of Herrnstein's equation, k, increased as sucrose concentration increased. This calls into question one common interpretation of Herrnstein's equation used to identify the behavioral mechanisms of drug action.
该研究旨在整合与速率相关的原理以及赫尔斯坦的双曲线匹配方程（1970），因为它们适用于药物效应。该研究还旨在评估一种用于解释药物作用行为机制的赫尔斯坦方程解释的有效性。八只大鼠被训练在一系列可变间隔（VI）强化程序下按压杠杆，使用蔗糖溶液（0.1M）作为强化物。在90次基线实验后，测试了3、6、12和17mg/kg硫酸吗啡对反应的影响。给予吗啡后，反应速率以剂量依赖性方式受到抑制。赫尔斯坦方程表明反应是相对强化率的函数，在大多数情况下，该方程很好地描述了反应与强化之间的关系。因此，将速率依赖性函数中用于预测药物效应的传统变量基线反应速率与一个新变量基线相对强化率进行了比较。相对强化率在预测药物效应方面与反应速率表现相当。为了测试赫尔斯坦双曲线是否能识别吗啡作用的行为机制，增加了蔗糖溶液的浓度（0.32M）。随着蔗糖浓度的增加，赫尔斯坦方程的y轴截距k增加。这对用于识别药物作用行为机制的赫尔斯坦方程的一种常见解释提出了质疑。
