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Neurosci Biobehav Rev. 2013 Mar;37(3):401-17. doi: 10.1016/j.neubiorev.2013.01.013. Epub 2013 Jan 17.
Cortical oscillatory synchrony in the gamma range has been attracting increasing attention in cognitive neuroscience ever since being proposed as a solution to the so-called binding problem. This growing literature is critically reviewed in both its basic neuroscience and cognitive aspects. A physiological "default assumption" regarding these oscillations is introduced, according to which they signal a state of physiological activation of cortical tissue, and the associated need to balance excitation with inhibition in particular. As such these oscillations would belong among a variety of generic neural control operations that enable neural tissue to perform its systems level functions, without implementing those functions themselves. Regional control of cerebral blood flow provides an analogy in this regard, and gamma oscillations are tightly correlated with this even more elementary control operation. As correlates of neural activation they will also covary with cognitive activity, and this typically suffices to account for the covariation between gamma activity and cognitive task variables. A number of specific cases of gamma synchrony are examined in this light, including the original impetus for attributing cognitive significance to gamma activity, namely the experiments interpreted as evidence for "binding by synchrony". This examination finds no compelling reasons to assign functional roles to oscillatory synchrony in the gamma range beyond its generic functions at the level of infrastructural neural control.
皮质振荡同步在伽马范围内已经吸引了越来越多的关注，自从被提出作为所谓的绑定问题的解决方案。这一不断增长的文献在其基础神经科学和认知方面都得到了批判性的回顾。根据生理“默认假设”，这些振荡信号表示皮质组织的生理激活状态，特别是需要平衡兴奋和抑制。因此，这些振荡将属于各种通用的神经控制操作，使神经组织能够执行其系统级功能，而不执行这些功能本身。在这方面，大脑血流的区域控制提供了一个类比，而伽马振荡与这个更基本的控制操作紧密相关。作为神经激活的相关物，它们也会与认知活动相关，而这通常足以解释伽马活动和认知任务变量之间的协变。从这个角度来看，检查了一些特定的伽马同步案例，包括最初将伽马活动归因于认知意义的动力，即解释为“同步绑定”证据的实验。这种检查发现，除了在基础设施神经控制层面的通用功能之外，没有令人信服的理由将伽马范围内的振荡同步赋予功能角色。
