據(jù)3月13日的《科學》雜志報道說,，研究人員已經(jīng)找到了一個與小鼠的害怕記憶有關(guān)聯(lián)的特別的神經(jīng)元亞群，這一發(fā)現(xiàn)將有助于闡明我們的人腦是如何儲存記憶的,。 這些發(fā)現(xiàn)可能還會有一天給試圖戰(zhàn)勝恐懼的人們帶來治療效果的改善。
Jin-Hee Han及其同僚用聽覺驚嚇訓練的方法來訓練小鼠,，接著又將其外側(cè)杏仁核的特殊神經(jīng)元亞群毀掉,，該神經(jīng)元亞群的被稱作CREB的轉(zhuǎn)錄因子的表達水平會在驚嚇訓練之后增加。 他們觀察到,，這些神經(jīng)元的消失損害了小鼠的經(jīng)過聽覺訓練時所產(chǎn)生的驚嚇的回憶能力,，但是隨機性的毀掉類似數(shù)目的外側(cè)杏仁核中的其它神經(jīng)元（即沒有CREB高度表達的那些神經(jīng)元）則不會防止這些驚嚇記憶的重新浮現(xiàn)。 那些缺乏富含CREB神經(jīng)元的小鼠的遺忘癥是持續(xù)性的,，而且對那些在驚嚇訓練中所獲得的某些記憶具有特異性,。 這些結(jié)果提示,，外側(cè)杏仁核中的那些CREB水平增加的神經(jīng)元對在那些經(jīng)過驚嚇訓練之后的時日中的記憶的表達是至關(guān)重要的。而且消除這些神經(jīng)元會永久性的消抹掉有關(guān)的驚嚇記憶,。
他們還找到了一個記憶“蹤跡”（或稱通路）的關(guān)鍵性的組分,，并暗示這些特別的神經(jīng)元在一個更為廣泛的驚嚇記憶神經(jīng)網(wǎng)絡中扮演著一個至關(guān)重要的角色。（生物谷Bioon.com）
生物谷推薦原始出處：
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.
