魏茨曼科学研究院(Weizmann Institue of Science)神经生物所的科学家Ilan Lampl博士发现了一个具有说服力的证据，说明神经细胞传讯的可能真相，这项研究发表于近期的Neuron期刊。
细胞在中枢神经系统会倾向于与其它细胞沟通，乃是藉由电讯号在神经元中传递讯息，问题是：大脑要怎么转译这些信息，才能让我们感知及理解在我们面前的世界呢？大部分的人认为这些电讯号会产生一些图谱(patterns)，转译为不同的认知信息，因此，大脑可以辨识桌子或椅子，因为每种东西都会在神经系统中产生不同序列的图谱，而大脑会对这些图谱给予不同的批注。重复出现的物体，其图谱便会很精确在神经系统的支配下出现一样的图谱。
然而，当Lampl及其研究团队记录并分析被麻醉的大鼠脑皮层(cortex)的活动时，他们发现产生图谱的数目与形态并没有差异，因此，他们推论先前看到的图谱，可能不是由于神经细胞电讯号所传达而来的，而仅是偶然发生的情况罢了。这项研究结果看来似乎对于神经讯息传递的争议有明显的贡献，Lampl博士说：「自1980年代起，许多神经科学家都相信神经电讯号传讯理论，但这份研究却提供了强烈的证据，大脑似乎不是用这些图谱来转译感知信息的。」
(资料来源 : Bio.com)
Neuron, Vol 53, 413-425, 01 February 2007
Article
Stochastic Emergence of Repeating Cortical Motifs in Spontaneous Membrane Potential Fluctuations In Vivo
Alik Mokeichev,1,2 Michael Okun,1,3 Omri Barak,1 Yonatan Katz,1 Ohad Ben-Shahar,2 and Ilan Lampl1,
1 Department of Neurobiology, Weizmann Institute of Science, Rehovot 76100, Israel
2 Department of Computer Science and The Zlotowski Center for Neuroscience, Ben Gurion University of the Negev, Beer-Sheva 84105, Israel
3 Department of Computer Science, The Hebrew University of Jerusalem, Jerusalem 91904, Israel
Corresponding author
Ilan Lampl
ilan.lampl@weizmann.ac.il
Summary
It was recently discovered that subthreshold membrane potential fluctuations of cortical neurons can precisely repeat during spontaneous activity, seconds to minutes apart, both in brain slices and in anesthetized animals. These repeats, also called cortical motifs, were suggested to reflect a replay of sequential neuronal firing patterns. We searched for motifs in spontaneous activity, recorded from the rat barrel cortex and from the cat striate cortex of anesthetized animals, and found numerous repeating patterns of high similarity and repetition rates. To test their significance, various statistics were compared between physiological data and three different types of stochastic surrogate data that preserve dynamical characteristics of the recorded data. We found no evidence for the existence of deterministically generated cortical motifs. Rather, the stochastic properties of cortical motifs suggest that they appear by chance, as a result of the constraints imposed by the coarse dynamics of subthreshold ongoing activity.
