Large-scale gamma-band phase synchronization and selective attention
Large-scale gamma-band phase synchronization and selective attention
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DOI：
10.1093/cercor/bhm073
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发表时间：
2008-02-01
期刊：
影响因子：
3.7
通讯作者：
Ward, Lawrence M.
中科院分区：
文献类型：
--
作者：
Doesburg, Sam M.;Roggeveen, Alexa B.;Ward, Lawrence M.
从分布式神经元的活动中解释一个连贯的意识感知和一个意向性主体的出现，是理解大脑如何产生高级认知过程的关键。伽马波段同步被认为是一种神经群体功能整合的机制，这些神经群体一起形成一个短暂的、大规模的、特定于任务和/或感知的网络。在注意力定向的背景下，这一机制的运作需要，代表出席地点的皮层区域应该比那些代表无人值守的位置显示出更多的伽马波段与其他皮层区域的同步。这种加强的同步性在对某一特定地点的注意力部署的同一时间范围内应该是显而易见的。为了观察这种效应，我们在受试者注意视野的一侧或另一侧时进行了脑电图记录（我们通过事件相关电位分析证实了这一点），并计算了相关电极对记录的信号之间的锁相统计。我们观察到增加的γ-波段相位同步的视觉皮层对侧的出席的位置和其他，广泛的，皮质区约240-380毫秒后的方向线索，确认预测的大规模伽玛同步网络面向的线索位置。
Explaining the emergence of a coherent conscious percept and an intentional agent from the activity of distributed neurons is key to understanding how the brain produces higher cognitive processes. Gamma-band synchronization has been proposed to be a mechanism for the functional integration of neural populations that together form a transitory, large-scale, task- and/or percept-specific network. The operation of this mechanism in the context of attention orienting entails that cortical regions representing attended locations should show more gamma-band synchronization with other cortical areas than would those representing unattended locations. This increased synchronization should be apparent in the same time frame as that of the deployment of attention to a particular location. In order to observe this effect, we made electroencephalogram recordings while subjects attended to one side or the other of the visual field (which we confirmed by event-related potential analysis) and calculated phase-locking statistics between the signals recorded at relevant electrode pairs. We observed increased gamma-band phase synchronization between visual cortex contralateral to the attended location and other, widespread, cortical areas approximately 240-380 ms after the directional cue was presented, confirming the prediction of a large-scale gamma synchronous network oriented to the cued location.