Allen M Todd, Chelius Lori, Masand Vivek, Gluck Mark A, Myers Catherine E, Schnirman Geoffrey
Center for Molecular and Behavioral Neuroscience, Rutgers University, Newark, NJ, USA.
Integr Physiol Behav Sci. 2002 Jul-Sep;37(3):188-214. doi: 10.1007/BF02734181.
The learning of an association between a CS and a US can be retarded by unreinforced presentations of the CS alone (termed latent inhibition or LI) or by un-correlated presentations of the CS and US (termed learned irrelevance or LIRR). In rabbit eyeblink conditioning, there have been some recent failures to replicate LI. LIRR has been hypothesized as producing a stronger retardation effect than LI based on both empirical studies and computational models. In the work presented here, we examined the relative strength of LI and LIRR in eyeblink conditioning in rabbits and humans. In both species, a number of preexposure trials sufficient to produce LIRR failed to produce LI (Experiments 1 & 3). Doubling the number of CS pre-exposures did produce LI in rabbits (Experiment 2), but not in humans (Experiment 4). LI was demonstrated in humans only after manipulations including an increased inter-trial interval or ITI (Experiment 5). Overall, it appears that LIRR is a more easily producible pre-exposure retardation effect than LI for eyeblink conditioning in both rabbits and humans. Several theoretical mechanisms for LI including the conditioned attention theory, stimulus compression, novelty, and the switching theory are discussed as possible explanations for the differences between LIRR and LI. Overall, future work involving testing the neural substrates of pre-exposure effects may benefit from the use of LIRR rather than LI.
单独呈现条件刺激（CS）而无强化（称为潜伏抑制或LI），或者呈现不相关的条件刺激和非条件刺激（称为习得性无关或LIRR），均可延缓CS与非条件刺激（US）之间联系的学习。在兔眨眼条件反射实验中，最近有一些未能重复出潜伏抑制现象的情况。基于实证研究和计算模型，有人提出习得性无关比潜伏抑制产生的延缓效应更强。在本文介绍的研究中，我们考察了兔和人眨眼条件反射中潜伏抑制和习得性无关的相对强度。在这两个物种中，进行足以产生习得性无关的多次预暴露试验均未能产生潜伏抑制（实验1和3）。将条件刺激预暴露次数加倍确实在兔中产生了潜伏抑制（实验2），但在人中未产生（实验4）。仅在进行包括增加试验间隔或ITI等操作后，才在人中证明了潜伏抑制（实验5）。总体而言，对于兔和人的眨眼条件反射，习得性无关似乎是比潜伏抑制更容易产生的预暴露延缓效应。文中讨论了潜伏抑制的几种理论机制，包括条件性注意理论、刺激压缩、新颖性和转换理论，作为对习得性无关和潜伏抑制之间差异的可能解释。总体而言，未来涉及测试预暴露效应神经基础的研究可能会受益于使用习得性无关而非潜伏抑制。
