生物谷：神經(jīng)學(xué)家長期以來相信大腦視覺處理方式是通過神經(jīng)元構(gòu)成的通路,，就好像通過電線從一處傳到另一處的電話信號(hào),。但最近來自Georgetown大學(xué)醫(yī)學(xué)中心的科學(xué)家發(fā)現(xiàn)，視覺信息還通過另一種方式處理,，類似于在大腦區(qū)域間來回振蕩,。結(jié)果發(fā)表在Neuron上。
生理學(xué)和生物物理學(xué)副教授Jian-young Wu是文章通訊作者,，他表示：“我們發(fā)現(xiàn)信號(hào)在大腦中類似波,，來回傳播。”這對(duì)于長期以來持有的大腦處理感官信息的方式是一個(gè)挑戰(zhàn),，Wu說：“一個(gè)傳統(tǒng)模型認(rèn)為神經(jīng)元結(jié)合在一起構(gòu)成特殊通路,。但是新的成像技術(shù)告訴我們并非完全如此。”
小組使用電壓靈敏染料成像技術(shù)對(duì)腦皮層類似波的模式進(jìn)行了成像,。他們用特殊染料結(jié)合到神經(jīng)元細(xì)胞膜上,，它們會(huì)隨著電壓穿過神經(jīng)元而改變顏色。而傳統(tǒng)上,，科學(xué)家通過電極來測量大腦的活動(dòng),。
Wu相信這一模式對(duì)于觸發(fā)和組織包含了大量神經(jīng)元的大腦活動(dòng)很重要。尋找在視覺處理過程中的波是邁向理解大腦如何處理感官信息的重要一步,。這一過程能幫助科學(xué)家了解帕金森氏癥和癲癇癥患者腦部產(chǎn)生的異常波,，以及癡呆癥患者為何無法正確組織神經(jīng)元的活動(dòng)。
Wu認(rèn)為還需要進(jìn)行進(jìn)一步的研究來理解人類大腦中正常和異常的波,。他表示：“了解大腦如何處理這些波能幫助我們了解宇宙中最復(fù)雜體系之一——大腦的功能,。” （教育部科技發(fā)展中心）
英文原文鏈接：http://www.physorg.com/news105119530.html
原始出處:
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
[email protected]
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.
