Schiffino Felipe L, Holland Peter C
Department of Psychological and Brain Sciences, Johns Hopkins University, Baltimore, MD 21218, USA.
Department of Psychological and Brain Sciences, Johns Hopkins University, Baltimore, MD 21218, USA.
Neurobiol Learn Mem. 2016 Sep;133:204-213. doi: 10.1016/j.nlm.2016.07.016. Epub 2016 Jul 15.
The surprising omission of a reinforcer can enhance the associability of the stimuli that were present when the reward prediction error was induced, so that they more readily enter into new associations in the future. Previous research from this laboratory identified brain circuit elements critical to the enhancement of stimulus associability by the omission of an expected event and to the subsequent expression of that altered associability in more rapid learning. These elements include the amygdala, the midbrain substantia nigra, the basal forebrain substantia innominata, the dorsolateral striatum, the secondary visual cortex, and the posterior parietal cortex. Here, we found that consolidation of a surprise-enhanced associability memory in a serial prediction task depends on processing in the amygdala central nucleus (CeA) after completion of sessions that included the surprising omission of an expected event. Post-surprise infusions of anisomycin, lidocaine, or muscimol prevented subsequent display of surprise-enhanced associability. Because previous studies indicated that CeA function is unnecessary for the expression of associability enhancements that were induced previously when CeA function was intact (Holland & Gallagher, 2006), we interpreted these results as indicating that post-surprise activity of CeA ("surprise replay") is necessary for the consolidation of altered associability memories elsewhere in the brain, such as the posterior parietal cortex (Schiffino et al., 2014a).
强化物的意外缺失能够增强在奖励预测误差产生时出现的刺激的关联性，从而使它们在未来更容易形成新的关联。该实验室之前的研究确定了一些脑回路元件，它们对于通过意外事件缺失来增强刺激关联性以及随后在更快学习中表达这种改变后的关联性至关重要。这些元件包括杏仁核、中脑黑质、基底前脑无名质、背外侧纹状体、次级视觉皮层和后顶叶皮层。在此，我们发现，在包含意外事件缺失的系列预测任务中，意外增强的关联性记忆的巩固取决于在包含意外事件缺失的实验结束后杏仁核中央核（CeA）的处理过程。意外事件后注入茴香霉素、利多卡因或蝇蕈醇可阻止随后意外增强的关联性的表现。因为先前的研究表明，当CeA功能完好时，CeA功能对于先前诱导的关联性增强的表达并非必要（Holland & Gallagher，2006），所以我们将这些结果解释为表明CeA的意外事件后活动（“意外重演”）对于大脑其他部位（如后顶叶皮层，Schiffino等人，2014a）改变后的关联性记忆的巩固是必要的。
