生物谷：神经学家长期以来相信大脑视觉处理方式是通过神经元构成的通路，就好像通过电线从一处传到另一处的电话信号。但最近来自Georgetown大学医学中心的科学家发现，视觉信息还通过另一种方式处理，类似于在大脑区域间来回振荡。结果发表在Neuron上。
生理学和生物物理学副教授Jian-young Wu是文章通讯作者，他表示：“我们发现信号在大脑中类似波，来回传播。”这对于长期以来持有的大脑处理感官信息的方式是一个挑战，Wu说：“一个传统模型认为神经元结合在一起构成特殊通路。但是新的成像技术告诉我们并非完全如此。”
小组使用电压灵敏染料成像技术对脑皮层类似波的模式进行了成像。他们用特殊染料结合到神经元细胞膜上，它们会随着电压穿过神经元而改变颜色。而传统上，科学家通过电极来测量大脑的活动。
Wu相信这一模式对于触发和组织包含了大量神经元的大脑活动很重要。寻找在视觉处理过程中的波是迈向理解大脑如何处理感官信息的重要一步。这一过程能帮助科学家了解帕金森氏症和癫痫症患者脑部产生的异常波，以及痴呆症患者为何无法正确组织神经元的活动。
Wu认为还需要进行进一步的研究来理解人类大脑中正常和异常的波。他表示：“了解大脑如何处理这些波能帮助我们了解宇宙中最复杂体系之一——大脑的功能。” （教育部科技发展中心）
英文原文链接：http://www.physorg.com/news105119530.html
原始出处:
Neuron, Vol 55, 119-129, 05 July 2007
Article
Compression and Reflection of Visually Evoked Cortical Waves
Weifeng Xu,1 Xiaoying Huang,1 Kentaroh Takagaki,1 and Jian-young Wu1,
1 Department of Physiology and Biophysics, Georgetown University Medical Center, Washington, DC 20057, USA
Corresponding author
Jian-young Wu
wuj@georgetown.edu
Neuronal interactions between primary and secondary visual cortical areas are important for visual processing, but the spatiotemporal patterns of the interaction are not well understood. We used voltage-sensitive dye imaging to visualize neuronal activity in rat visual cortex and found visually evoked waves propagating from V1 to other visual areas. A primary wave originated in the monocular area of V1 and was “compressed” when propagating to V2. A reflected wave initiated after compression and propagated backward into V1. The compression occurred at the V1/V2 border, and local GABAA inhibition is important for the compression. The compression/reflection pattern provides a two-phase modulation: V1 is first depolarized by the primary wave, and then V1 and V2 are simultaneously depolarized by the reflected and primary waves, respectively. The compression/reflection pattern only occurred for evoked waves and not for spontaneous waves, suggesting that it is organized by an internal mechanism associated with visual processing.
