小脑和大脑皮层都可以收到来自体觉系统的输入信息。有人曾经指出,这两个区域的相互作用可以通过正确选择和执行指令来完成。但目前科学家尚不清楚的是:这种相互作用是如何发生的。
在大脑皮层,信息输入会引起有节律的变化,从而为信息的输入和随后的输出提供了一个时空编码策略。在6月12日的《神经元》(Neuron)杂志上,Middleton等人报道了发生在小脑的烟碱受体亚型激活期的类似节律变化模式。伽马振荡(30–80 Hz)和非常快速振荡(VFOs, 80–160 Hz)都在缺乏功能谷氨酸的连接时,由小脑内皮层的电路所产生。作为在新大脑皮层,伽玛节律依赖于伽马氨基丁酸(GABAA)受体介导的抑制作用,而VFOs只需要非经典连接的细胞间网络。
小脑皮层作为新皮层在同一频率段范围内产生节律变化的能力表明,频率带作为一项共同的时空代码,也可能会发生小脑皮质的信息传递。(生物谷Bioon.com)
生物谷推荐原始出处:
Neuron,Vol 58, 763-774, 12 June 2008,Steven J. Middleton, Miles A. Whittington
High-Frequency Network Oscillations in Cerebellar Cortex
Steven J. Middleton,1,4 Claudia Racca,1 Mark O. Cunningham,1 Roger D. Traub,2 Hannah Monyer,3 Thomas Knöpfel,4 Ian S. Schofield,5 Alistair Jenkins,5 and Miles A. Whittington1,
1 Institute of Neuroscience, The Medical School, Newcastle University, Newcastle upon Tyne, NE2 4HH, UK
2 Departments of Physiology, Pharmacology, and Neurology, SUNY Downstate Medical Center, Brooklyn, NY 11203, USA
3 Department of Clinical Neurobiology, University Hospital of Neurology, IZN, Im Neuenheimer Feld 364, 69120 Heidelberg, Germany
4 Laboratory for Neuronal Circuit Dynamics, RIKEN Brain Science Institute, 2-1 Hirosawa, Wako-shi, Saitama 351-0198, Japan
5 Regional Neurosciences Center, Newcastle General Hospital, Newcastle upon Tyne, NE7 7DN, UK
Corresponding author
Miles A. Whittington
m.a.whittington@ncl.ac.uk
Summary
Both cerebellum and neocortex receive input from the somatosensory system. Interaction between these regions has been proposed to underpin the correct selection and execution of motor commands, but it is not clear how such interactions occur. In neocortex, inputs give rise to population rhythms, providing a spatiotemporal coding strategy for inputs and consequent outputs. Here, we show that similar patterns of rhythm generation occur in cerebellum during nicotinic receptor subtype activation. Both gamma oscillations (30–80 Hz) and very fast oscillations (VFOs, 80–160 Hz) were generated by intrinsic cerebellar cortical circuitry in the absence of functional glutamatergic connections. As in neocortex, gamma rhythms were dependent on GABAA receptor-mediated inhibition, whereas VFOs required only nonsynaptically connected intercellular networks. The ability of cerebellar cortex to generate population rhythms within the same frequency bands as neocortex suggests that they act as a common spatiotemporal code within which corticocerebellar dialog may occur.