Model-founded explorations of the roles of molecular layer inhibition in regulating Purkinje cell responses in cerebellar cortex: more trouble for the beam hypothesis
Model-founded explorations of the roles of molecular layer inhibition in regulating Purkinje cell responses in cerebellar cortex: more trouble for the beam hypothesis
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DOI：
10.3389/fncel.2010.00027
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发表时间：
2010-07-01
影响因子：
5.3
通讯作者：
Bower, James M.
中科院分区：
文献类型：
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作者：
Bower, James M.
在过去50年的大部分时间里，对小脑皮质回路中抑制的功能解释一直被一个相对简单的概念所主导，即兴奋性和抑制性树突输入之和，如果这个总和超过了体细胞的阈值，浦肯野细胞就会产生动作电位。因此，抑制传统上被降级为雕刻，限制或阻止激发的作用。在网络层面，这个相对简单的概念体现在诸如“环绕抑制”之类的机制中，这种机制被认为是“塑造”或“调节”兴奋性神经元反应。在小脑中，除了一种细胞（颗粒细胞）外，所有细胞类型都是抑制性的，这些关于抑制作用的假设继续占主导地位。基于我们最近一系列的模型和实验研究，我们现在怀疑抑制可能在小脑皮层的生理和功能组织中起着更复杂、更微妙和更重要的作用。本文概述了基于模型的研究如何改变我们对前馈分子层抑制在小脑皮层中的作用的看法。这些结果不仅对继续努力了解小脑的计算功能具有重要意义，而且还可能揭示这种典型的大型脊椎动物大脑结构进化的重要特征。
For most of the last 50 years, the functional interpretation for inhibition in cerebellar cortical circuitry has been dominated by the relatively simple notion that excitatory and inhibitory dendritic inputs sum, and if that sum crosses threshold at the soma the Purkinje cell generates an action potential. Thus, inhibition has traditionally been relegated to a role of sculpting, restricting, or blocking excitation. At the level of networks, this relatively simply notion is manifest in mechanisms like "surround inhibition" which is purported to "shape" or "tune" excitatory neuronal responses. In the cerebellum, where all cell types except one (the granule cell) are inhibitory, these assumptions regarding the role of inhibition continue to dominate. Based on our recent series of modeling and experimental studies, we now suspect that inhibition may play a much more complex, subtle, and central role in the physiological and functional organization of cerebellar cortex. This paper outlines how model-based studies are changing our thinking about the role of feed-forward molecular layer inhibition in the cerebellar cortex. The results not only have important implications for continuing efforts to understand what the cerebellum computes, but might also reveal important features of the evolution of this large and quintessentially vertebrate brain structure.