Department of Psychological Science, Program in Neuroscience and Behavior, Vassar College, Poughkeepsie, NY 12604, United States.
Neurosci Biobehav Rev. 2016 Dec;71:409-417. doi: 10.1016/j.neubiorev.2016.09.028. Epub 2016 Sep 28.
Memories of threatening, fear-evoking events can persist even over a lifetime. While fear memory is widely considered to be a highly persistent and durable form of memory, its circuits are not. This article reviews the dynamic temporal representation of remote fear memory in the brain, at the level of local circuits and distributed networks. Data from the study of Pavlovian cued fear conditioning suggests memory retrieval remains amygdala-dependent, even over protracted time scales, all the while interconnected cortical and subcortical circuits are newly recruited and progressively reorganized. A deeper understanding into how the neurocircuitry of cued fear memory reorganizes with the passage of time will advance our ongoing search for the elusive physical changes representing fear memories in the brain. Considering that persistent, pathological fear memories are a hallmark feature of post-traumatic stress disorder (PTSD), the behavioral and circuit-level study of remote cued fear memory retrieval adds a key element towards a systems understanding of PTSD.
威胁性、引发恐惧的事件的记忆甚至可以持续一生。虽然恐惧记忆被广泛认为是一种高度持久和耐用的记忆形式，但它的回路并非如此。本文回顾了大脑中远程恐惧记忆的动态时间表示，包括局部回路和分布式网络。来自条件性恐惧反射学习研究的数据表明，即使在很长的时间尺度上，记忆检索仍然依赖于杏仁核，同时，相互连接的皮质和皮质下回路被新招募并逐渐重新组织。更深入地了解条件性恐惧记忆的神经回路如何随时间重新组织，将有助于我们继续寻找大脑中代表恐惧记忆的难以捉摸的物理变化。鉴于持续存在的病理性恐惧记忆是创伤后应激障碍（PTSD）的一个显著特征，远程条件性恐惧记忆检索的行为和回路水平研究为 PTSD 的系统理解增加了一个关键要素。
