Alarcón Daniel, Bonardi Charlotte
School of Psychology.
J Exp Psychol Anim Learn Cogn. 2016 Jan;42(1):82-94. doi: 10.1037/xan0000087. Epub 2015 Nov 16.
Four experiments examined the effect of Pavlovian conditioned inhibition on specific Pavlovian-instrumental transfer (PIT) in human participants. The task comprised an instrumental phase in which 2 responses (R1, R2) were each paired with 1 of 2 outcomes (O1, O2: R1→O1, R2→O2), and a Pavlovian phase, in which 2 conditioned stimuli (CSs), CS1 and CS2 each signaled 1 of the 2 outcomes (CS1→O1, CS2→O2). In Experiments 1-2 a conditioned inhibitor, X, predicted the omission of 1 of the outcomes (e.g., CS1→O1, CS1X→nothing). In a subsequent test, performance of R1 and R2 was examined in the presence of CS1 and CS2. A specific PIT effect was observed: R1 was performed more than R2 during CS1, and R2 more than R1 during CS2. This PIT effect was significantly reduced by the presence of the inhibitor X in Experiment 1, in which the Pavlovian phase followed the instrumental phase, and in Experiment 2 in which it preceded it. No such effect was observed when X was presented in the absence of any expectation of the outcomes during the PIT test (Experiment 3a), or when X was trained as a signal for an alternative outcome (Experiment 3b). These results are consistent with the suggestion that the specific PIT effect occurs through a stimulus-outcome-response (S-O-R) mechanism, according to which the CS evokes a representation of the outcome which in turn elicits the response (e.g., CS1→O1→R1). The conditioned inhibitor suppresses performance of the response by suppressing activation of the outcome representation.
四项实验研究了巴甫洛夫条件性抑制对人类参与者特定巴甫洛夫-工具性迁移（PIT）的影响。该任务包括一个工具性阶段，其中两种反应（R1、R2）分别与两种结果（O1、O2：R1→O1，R2→O2）之一配对，以及一个巴甫洛夫阶段，其中两个条件刺激（CSs），CS1和CS2分别预示两种结果之一（CS1→O1，CS2→O2）。在实验1-2中，一个条件性抑制剂X预示其中一种结果的缺失（例如，CS1→O1，CS1X→无结果）。在随后的测试中，在CS1和CS2出现时检查R1和R2的表现。观察到一种特定的PIT效应：在CS1期间，R1的表现多于R2，而在CS2期间，R2的表现多于R1。在实验1（其中巴甫洛夫阶段在工具性阶段之后）和实验2（其中巴甫洛夫阶段在工具性阶段之前）中，抑制剂X的存在显著降低了这种PIT效应。当在PIT测试期间在没有任何结果预期的情况下呈现X时（实验3a），或者当X被训练为替代结果的信号时（实验3b），未观察到这种效应。这些结果与以下观点一致，即特定的PIT效应是通过刺激-结果-反应（S-O-R）机制发生的，根据该机制，CS唤起结果的表征，进而引发反应（例如，CS1→O1→R1）。条件性抑制剂通过抑制结果表征的激活来抑制反应的表现。
