据3月13日的《科学》杂志报道说，研究人员已经找到了一个与小鼠的害怕记忆有关联的特别的神经元亚群，这一发现将有助于阐明我们的人脑是如何储存记忆的。 这些发现可能还会有一天给试图战胜恐惧的人们带来治疗效果的改善。
Jin-Hee Han及其同僚用听觉惊吓训练的方法来训练小鼠，接着又将其外侧杏仁核的特殊神经元亚群毁掉，该神经元亚群的被称作CREB的转录因子的表达水平会在惊吓训练之后增加。 他们观察到，这些神经元的消失损害了小鼠的经过听觉训练时所产生的惊吓的回忆能力，但是随机性的毁掉类似数目的外侧杏仁核中的其它神经元（即没有CREB高度表达的那些神经元）则不会防止这些惊吓记忆的重新浮现。 那些缺乏富含CREB神经元的小鼠的遗忘症是持续性的，而且对那些在惊吓训练中所获得的某些记忆具有特异性。 这些结果提示，外侧杏仁核中的那些CREB水平增加的神经元对在那些经过惊吓训练之后的时日中的记忆的表达是至关重要的。而且消除这些神经元会永久性的消抹掉有关的惊吓记忆。
他们还找到了一个记忆“踪迹”（或称通路）的关键性的组分，并暗示这些特别的神经元在一个更为广泛的惊吓记忆神经网络中扮演着一个至关重要的角色。（生物谷Bioon.com）
生物谷推荐原始出处：
Science 13 March 2009:DOI: 10.1126/science.1164139
Selective Erasure of a Fear Memory
Jin-Hee Han,1,2,3 Steven A. Kushner,1,4 Adelaide P. Yiu,1,2 Hwa-Lin (Liz) Hsiang,1,2 Thorsten Buch,5 Ari Waisman,6 Bruno Bontempi,7 Rachael L. Neve,8 Paul W. Frankland,1,2,3 Sheena A. Josselyn1,2,3*
Memories are thought to be encoded by sparsely distributed groups of neurons. However, identifying the precise neurons supporting a given memory (the memory trace) has been a long-standing challenge. We have shown previously that lateral amygdala (LA) neurons with increased cyclic adenosine monophosphate response element–binding protein (CREB) are preferentially activated by fear memory expression, which suggests that they are selectively recruited into the memory trace. We used an inducible diphtheria-toxin strategy to specifically ablate these neurons. Selectively deleting neurons overexpressing CREB (but not a similar portion of random LA neurons) after learning blocked expression of that fear memory. The resulting memory loss was robust and persistent, which suggests that the memory was permanently erased. These results establish a causal link between a specific neuronal subpopulation and memory expression, thereby identifying critical neurons within the memory trace.
1 Program in Neurosciences and Mental Health, Hospital for Sick Children, 555 University Avenue, Toronto, ON, M5G 1X8, Canada.
2 Institute of Medical Sciences, University of Toronto, Toronto, ON, M5G 1X8, Canada.
3 Department of Physiology, University of Toronto, Toronto, ON, M5G 1X8, Canada.
4 Department of Psychiatry, Erasmus University Medical Center, 3015 CE Rotterdam, Netherlands.
5 Department of Pathology, University of Zurich, CH-8057 Zurich, Switzerland.
6 I.Medizinische Klinik und Poliklinik, Johannes Gutenberg-Universit?t Mainz, 55131 Mainz, Germany.
7 Centre de Neurosciences Intégratives et Cognitives, CNRS UMR5228 and University of Bordeaux 1, 33405 Talence, France.
8 Department of Brain and Cognitive Sciences, Massachusetts Institute of Technology, Cambridge, MA 02139, USA.
