Weatherly J N., Himle M B., Plumm K M., Moulton P L.
Department of Psychology, University of North Dakota, 58202-8380, Grand Forks, ND, USA
Behav Processes. 2001 Oct 1;56(1):49-66. doi: 10.1016/s0376-6357(01)00187-5.
Previous research has demonstrated that rats' rates of lever pressing for low-concentration liquid-sucrose reinforcers are increased when food-pellet, rather than sucrose, reinforcement will be upcoming in the same session (i.e. induction). The present experiments were designed to determine whether this induction was the product of 'anticipatory responses' for the upcoming food pellets being added to the responses being made for the currently available sucrose reinforcement. Experiment 1 tested this idea by summing sucrose-reinforced responding and 'anticipatory responding' from different conditions and comparing the sum to responding from a third condition in which subjects responded for sucrose when food-pellet reinforcement was upcoming. The comparison yielded similar response rates. Experiment 2 employed a blackout, of different durations in different conditions, to delay the upcoming food-pellet reinforcement. Consistent with the anticipatory-responding account, the delay decreased the size of the induction. However, results from the blackouts were not entirely consistent with the anticipatory-responding explanation. Experiment 3 provided, in some conditions, sucrose and food-pellet reinforcement in the first and second halves of the session, respectively, for responding on separate levers. These conditions separated 'anticipatory responses' for the food pellets from responses for the sucrose reinforcers. However, induction in responding for sucrose was still present. Together, these experiments demonstrate that, although anticipatory responses may contribute to induction in some instances, they are not solely responsible for the effect.
先前的研究表明，当在同一实验环节中即将出现食物颗粒而非蔗糖强化物时（即诱导），大鼠按压杠杆以获取低浓度液体蔗糖强化物的速率会增加。本实验旨在确定这种诱导是否是即将到来的食物颗粒的“预期反应”与当前可得蔗糖强化物的反应相加的产物。实验1通过将不同条件下蔗糖强化反应和“预期反应”相加，并将总和与第三种条件下的反应进行比较来测试这一想法，在第三种条件下，当即将出现食物颗粒强化物时，受试者对蔗糖做出反应。比较得出了相似的反应速率。实验2在不同条件下采用不同持续时间的遮光处理，以延迟即将到来的食物颗粒强化物。与预期反应的说法一致，延迟减小了诱导的程度。然而，遮光处理的结果并不完全符合预期反应的解释。实验3在某些条件下，分别在实验环节的前半段和后半段为在不同杠杆上的反应提供蔗糖和食物颗粒强化物。这些条件将对食物颗粒的“预期反应”与对蔗糖强化物的反应区分开来。然而，对蔗糖反应的诱导仍然存在。总之，这些实验表明，尽管预期反应在某些情况下可能有助于诱导，但它们并非该效应的唯一原因。
