Kehoe EJ
School of Psychology, The University of New South Wales, 2052, NSW, Sydney, Australia
Behav Processes. 2000 Aug 17;50(2-3):155-164. doi: 10.1016/s0376-6357(00)00099-1.
Five experiments were conducted in which the onset of a tone conditioned stimulus (CS) preceded the unconditioned stimulus (US) by 500 ms. Across experiments, the offset of the CS was extended past the offset of the US by values ranging from 0 ms to 40000 ms. Extensions of the CS of 2000 ms or greater produced acquisition of a conditioned response (CR) that was as fast or faster than in the no-extension condition (0 ms). While extension of a forward tone CS after the US enhanced excitatory conditioning, insertion of another CS (light) in a purely backward relationship with the US passed only a retardation test, indicative of latent inhibition, and not a summation test needed for conditioned inhibition. The results add to the evidence that excitatory and inhibitory processes are both engaged following US offset. Alternative theories of CS processing are discussed.
进行了五项实验，其中音调条件刺激（CS）的开始比无条件刺激（US）提前500毫秒。在各项实验中，CS的结束时间比US的结束时间延长了0毫秒至40000毫秒不等。CS延长2000毫秒或更长时间会产生条件反应（CR），其速度与无延长条件（0毫秒）下的速度一样快或更快。虽然在美国之后延长正向音调CS会增强兴奋性条件作用，但以与美国完全反向的关系插入另一个CS（光）仅通过了延迟测试，表明存在潜伏抑制，而未通过条件抑制所需的总和测试。这些结果进一步证明，在美国结束后，兴奋性和抑制性过程都会参与其中。还讨论了CS处理的替代理论。
