Frohardt R J, Guarraci F A, Bouton M E
Department of Psychology, University of Vermont, Burlington 05405, USA.
Behav Neurosci. 2000 Apr;114(2):227-40. doi: 10.1037//0735-7044.114.2.227.
Three conditioned suppression experiments with rats examined the role of the hippocampus in 2 effects of context after extinction. Reinstatement is the context-specific recovery of fear to an extinguished conditioned stimulus (CS) that occurs following independent presentations of the unconditioned stimulus (US), after extinction. Renewal is the recovery of fear when the CS is presented in the context in which it was conditioned, after extinction in a different context. Results indicated that neurotoxic lesions of the hippocampus, performed before conditioning, abolished reinstatement, which depends on context-US associations, but not renewal, which does not. This dissociation is not the result of differences in the recentness of context learning that ordinarily governs the 2 effects. The results suggest that the hippocampus is necessary for some, but not all, types of contextual learning.
三项以大鼠为对象的条件性抑制实验，研究了海马体在消退后情境的两种效应中的作用。恢复是指在消退后，无条件刺激（US）单独呈现后，对已消退的条件刺激（CS）的情境特异性恐惧恢复。更新是指在不同情境中消退后，当CS在其被条件化的情境中呈现时恐惧的恢复。结果表明，在条件化之前进行的海马体神经毒性损伤消除了恢复效应，恢复效应依赖于情境-US关联，但没有消除更新效应，更新效应并不依赖于此。这种分离不是通常控制这两种效应的情境学习近期性差异的结果。结果表明，海马体对于某些但并非所有类型的情境学习是必要的。
