Arshavsky Yuri I
Institute for Nonlinear Science, University of California San Diego, La Jolla, CA 92093-0402, USA.
Prog Neurobiol. 2006 Oct;80(3):99-113. doi: 10.1016/j.pneurobio.2006.09.004. Epub 2006 Oct 30.
Memorizing new facts and events means that entering information produces specific physical changes within the brain. According to the commonly accepted view, traces of memory are stored through the structural modifications of synaptic connections, which result in changes of synaptic efficiency and, therefore, in formations of new patterns of neural activity (the hypothesis of synaptic plasticity). Most of the current knowledge on learning and initial stages of memory consolidation ("synaptic consolidation") is based on this hypothesis. However, the hypothesis of synaptic plasticity faces a number of conceptual and experimental difficulties when it deals with potentially permanent consolidation of declarative memory ("system consolidation"). These difficulties are rooted in the major intrinsic self-contradiction of the hypothesis: stable declarative memory is unlikely to be based on such a non-stable foundation as synaptic plasticity. Memory that can last throughout an entire lifespan should be "etched in stone." The only "stone-like" molecules within living cells are DNA molecules. Therefore, I advocate an alternative, genomic hypothesis of memory, which suggests that acquired information is persistently stored within individual neurons through modifications of DNA, and that these modifications serve as the carriers of elementary memory traces.
记住新的事实和事件意味着输入信息会在大脑中产生特定的物理变化。根据普遍接受的观点,记忆痕迹是通过突触连接的结构改变来存储的,这会导致突触效率的变化,进而形成新的神经活动模式(突触可塑性假说)。目前关于学习和记忆巩固初始阶段(“突触巩固”)的大部分知识都是基于这一假说。然而,当突触可塑性假说涉及陈述性记忆的潜在永久性巩固(“系统巩固”)时,它面临着一些概念和实验上的困难。这些困难源于该假说的主要内在矛盾:稳定的陈述性记忆不太可能基于像突触可塑性这样不稳定的基础。能够持续一生的记忆应该是“铭刻在石头上”的。活细胞内唯一“像石头一样”的分子是DNA分子。因此,我主张一种替代性的记忆基因组假说,该假说认为获得的信息通过DNA的修饰持久地存储在单个神经元内,并且这些修饰作为基本记忆痕迹的载体。