Ito M
RIKEN Brain Science Institute, 2-1 Hirosawa, Wako, 351-0198, Saitama, Japan.
Brain Res. 2000 Dec 15;886(1-2):237-245. doi: 10.1016/s0006-8993(00)03142-5.
How the elaborate neuronal circuit in the cerebellum operates and is involved in motor learning is a question addressed in earnest in studies on the cerebellum. During the past four decades, experimental studies have revealed circuit and module structures of the cerebellum, established long-term depression (LTD) as a unique and characteristic type of synaptic plasticity in the cerebellum, and analysed signal contents of activates of cerebellar neurons related to motor learning. In the 1990s, these studies were developed to detailed analyses of the signal transduction underlying LTD, and to uncovering the involvement of the cerebellum in cognitive function. On the other hand, theoretical studies yielded epochal Marr-Albus network models of the cerebellum around 1970, and introduced control system principles explaining the essential roles of the cerebellum in motor learning as providing internal models, both forward and inverse. The author maintains the hypothesis that reorganisation of the neuronal circuit by error-driven induction of LTD constitutes the major memory and learning mechanisms of the cerebellum. In this article, we examine the validity of the hypothesis in light of currently available data in recent studies of the cerebellum.
小脑内精细的神经元回路是如何运作并参与运动学习的，这是小脑研究中认真探讨的一个问题。在过去的四十年里，实验研究揭示了小脑的回路和模块结构，确立了长时程抑制（LTD）作为小脑中一种独特且具有特征性的突触可塑性类型，并分析了与运动学习相关的小脑神经元激活的信号内容。在20世纪90年代，这些研究发展到对LTD潜在信号转导的详细分析，以及揭示小脑在认知功能中的作用。另一方面，理论研究在1970年左右产生了具有划时代意义的小脑马尔-阿尔布斯网络模型，并引入了控制系统原理，解释了小脑在运动学习中作为提供正向和反向内部模型的重要作用。作者坚持这样的假设，即由错误驱动的LTD诱导引起的神经元回路重组构成了小脑的主要记忆和学习机制。在本文中，我们根据小脑近期研究中的现有数据来检验这一假设的有效性。
