Cerebellar synaptic plasticity. Relation to learning versus neural activity.
Cerebellar synaptic plasticity. Relation to learning versus neural activity.
复制标题
小脑突触可塑性。
DOI：
10.1111/j.1749-6632.1991.tb25927.x
复制
发表时间：
1991
影响因子：
5.2
通讯作者：
Anderson,BJ
中科院分区：
文献类型：
--
作者：
Greenough,WT;Anderson,BJ
这本书的标题是《学习和发展中的活动驱动的中枢神经系统变化》，这让我们强调了哪些事件实际上是启动神经系统功能(和结构)变化所必需的和充分的。我们认为，有大量证据表明，活动本身并不总是导致功能组织变化的关键因素，尽管在某些情况下，它似乎足以引起高活性区域代谢支持的变化。相反，学习似乎有一些非常特殊的要求，或者神经活动模式的一些其他变化，以驱动中枢神经系统进行自我重组。这一要求最终必须以导致职能组织变化的一系列步骤在细胞级别上表达。虽然这些步骤很可能最终被理解为细胞变化背后的分子事件，但我们的目标是从行为的角度来理解这种重组。我们试图知道施加在受试者身上的行为需求是否可以决定神经反应，如果是的话，又是如何决定的。正如本文后面所讨论的，我们已经看到学习后小脑的结构变化。因此，我们很好奇这些变化是如何发生的，以及它们可能如何适应小脑皮质的总体输出。实验结果和理论都预测，小脑皮质在行为适应中发挥着可塑性作用。如图1所示，有两个主要的兴奋性信息输入，都来自脑干和脊髓部位，以及一个单一的输出神经元，浦肯野细胞。攀爬纤维主要或完全来自下橄榄，携带来自躯体感觉、前庭、视觉和少量听觉模式的信息。苔藓纤维来自脑干和脊髓中的不同位置，也携带感觉输入，因此对于这两个传入系统传递的信息类型没有简单、直接的区别。有时，同样的浦肯野细胞可以被来自同一外周位置的爬行纤维和平行纤维输入激活。‘-’在这两个系统中，输入受到来自前脑的下行投射的调制。攀爬纤维直接终止于浦肯野细胞，每个浦肯野细胞接受多个突触
The title of this volume, Activity-Driven CNS Changes in Learning and Development, has led us to emphasize what events are actually necessary and sufficient to initiate functional (and structural) change in the nervous system. We believe that there is substantial evidence that activity, per se, is not invariably the critical factor for the induction of a change in functional organization, although it appears to be sufficient to bring about changes in the metabolic support of highly active regions in some cases. Rather, there appears to be some very specific requirement for learning, or some other change in the pattern of neural activity, to drive the CNS to reorganize itself. This requirement must ultimately be expressed at the cellular level in a sequence of steps leading to changes in functional organization. Although the steps may well be understood ultimately in terms of the molecular events that underlie the cellular change, our goal is to understand this reorganization from the perspective of behavior. We seek to know whether the behavioral demands placed upon a subject can determine the neural response and if so how. As discussed later in this article, we have seen structural changes in the cerebellum following learning. As a result, we are curious as to how these changes come about, and how they might fit in the overall output of the cerebellar cortex.Both experimental results and theory predict that the cerebellar cortex performs a plastic role in behavioral adaptation. As FIGURE 1 shows, there are two major excitatory informational inputs, both arising from brainstem and spinal loci, and a single output neuron, the Purkinje cell.'Climbing fibers, which originate largely or exclusively from the inferior olive, carry information from the somatosensory, vestibular, visual, and to a lesser extent auditory modalities. Mossy fibers arise from various locations in the brainstem and spinal cord and also carry sensory input, such that there is no simple, straightforward distinction with regard to the types of information the two affer., t systems convey. On occasion the same Purkinje cell may be activated by both climbing fiber and parallel fiber input from the same peripheral location.'-'In both systems the input is modulated by descending projections from the forebrain. Climbing fibers terminate directly upon Purkinje cells, each Purkinje cell receiving multiple synaptic