Belke Terry W, Pierce W David
Mount Allison University, Sackville, New Brunswick, Canada.
University of Alberta, Edmonton, Alberta, Canada.
Behav Processes. 2014 Mar;103:35-42. doi: 10.1016/j.beproc.2013.11.010. Epub 2013 Dec 1.
The current study investigated the effect of motivational manipulations on operant wheel running for sucrose reinforcement and on wheel running as a behavioral consequence for lever pressing, within the same experimental context. Specifically, rats responded on a two-component multiple schedule of reinforcement in which lever pressing produced the opportunity to run in a wheel in one component of the schedule (reinforcer component) and wheel running produced the opportunity to consume sucrose solution in the other component (operant component). Motivational manipulations involved removal of sucrose contingent on wheel running and providing 1h of pre-session wheel running. Results showed that, in opposition to a response strengthening view, sucrose did not maintain operant wheel running. The motivational operations of withdrawing sucrose or providing pre-session wheel running, however, resulted in different wheel-running rates in the operant and reinforcer components of the multiple schedule; this rate discrepancy revealed the extrinsic reinforcing effects of sucrose on operant wheel running, but also indicated the intrinsic reinforcement value of wheel running across components. Differences in wheel-running rates between components were discussed in terms of arousal, undermining of intrinsic motivation, and behavioral contrast.
本研究在相同实验背景下，考察了动机操控对为获取蔗糖强化物而进行的操作性跑轮行为的影响，以及对作为杠杆按压行为结果的跑轮行为的影响。具体而言，大鼠在一个双成分多重强化程序中做出反应，在该程序的一个成分（强化物成分）中，杠杆按压可产生在跑轮中跑步的机会，而在另一个成分（操作性成分）中，跑轮跑步可产生饮用蔗糖溶液的机会。动机操控包括依据跑轮情况移除蔗糖以及在实验开始前提供1小时的跑轮跑步。结果表明，与反应强化观点相反，蔗糖并不能维持操作性跑轮行为。然而，移除蔗糖或在实验开始前提供跑轮跑步的动机操作，在多重程序的操作性成分和强化物成分中导致了不同的跑轮速率；这种速率差异揭示了蔗糖对操作性跑轮行为的外在强化作用，但也表明了跑轮行为在各成分中的内在强化价值。各成分之间跑轮速率的差异从唤醒、内在动机的削弱以及行为对比等方面进行了讨论。
