Department of Anatomy and Cell Biology, University of Melbourne, Melbourne, Victoria 3010, Australia.
Learn Mem. 2011 Oct 3;18(10):678-87. doi: 10.1101/lm.2314311. Print 2011.
The identity and distribution of neurons that are involved in any learning or memory event is not known. In previous studies, we identified a discrete population of neurons in the lateral amygdala that show learning-specific activation of a c-fos-regulated transgene following context fear conditioning. Here, we have extended these studies to look throughout the amygdala for learning-specific activation. We identified two further neuronal populations, in the amygdalo-striatal transition area and medial amygdala, that show learning-specific activation. We also identified a population of hypothalamic neurons that show strong learning-specific activation. In addition, we asked whether these neurons are activated following recall of fear-conditioning memory. None of the populations of neurons we identified showed significant memory-recall-related activation. These findings suggest that a series of discrete populations of neurons are involved in fear learning in amygdala and hypothalamus. The lack of reactivation during memory recall suggests that these neurons either do not undergo substantial change following recall, or that c-fos is not involved in any such activation and change.
目前还不知道参与任何学习或记忆事件的神经元的身份和分布。在之前的研究中，我们在外侧杏仁核中鉴定出了一个离散的神经元群体，在经过情境恐惧条件作用后，该神经元群体中 c-fos 调控的转基因表现出特定的学习激活。在这里，我们将这些研究扩展到整个杏仁核，以寻找特定的学习激活。我们在杏仁核-纹状体过渡区和内侧杏仁核中又鉴定出两个表现出特定学习激活的神经元群体。我们还鉴定出了一群表现出强烈特定学习激活的下丘脑神经元。此外，我们还询问了这些神经元是否在恐惧条件记忆的回忆中被激活。我们鉴定的神经元群体中没有一个表现出明显的记忆回忆相关激活。这些发现表明，一系列离散的神经元群体参与了杏仁核和下丘脑的恐惧学习。在记忆回忆过程中没有发现这些神经元的再激活，这表明这些神经元要么在回忆后没有发生实质性变化，要么 c-fos 没有参与任何这种激活和变化。
