Top-down processing mediated by interareal synchronization
Top-down processing mediated by interareal synchronization
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DOI：
10.1073/pnas.97.26.14748
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发表时间：
2000-12-19
影响因子：
11.1
通讯作者：
König, P
中科院分区：
文献类型：
--
作者：
von Stein, A;Chiang, C;König, P
感知和皮层反应不仅由外部刺激“自下而上”驱动，而且还受到内部约束（如预期或当前行为目标）的影响。为了研究这种自上而下的影响的神经生理机制，我们分析了在不同的行为意义的刺激感知过程中，不同层次的皮层神经元的时间相互作用。我们发现，在中频范围内（θ和α：4-12 Hz）的相互作用强烈依赖于相关的行为，相位关系和层特异性表明自上而下的相互作用。对于新的意想不到的刺激，大概是在前馈方式处理，没有这样的相互作用发生，但高频相互作用（伽马，20-100赫兹）进行了观察。因此，皮质同步反映了动物的内部状态，并可能介导自上而下的过程。
Perception and cortical responses are not only driven "bottom-up" by the external stimulus but are altered by internal constraints such as expectancy or the current behavioral goal. To investigate neurophysiological mechanisms of such top-down effects, we analyzed the temporal interactions of neurons on different levels of the cortical hierarchy during perception of stimuli with varying behavioral significance. We found that interareal interactions in a middle-frequency range (theta and alpha :4-12 Hz) strongly depend on the associated behavior, with a phase relationship and a layer specificity indicating a top-down-directed interaction. For novel unexpected stimuli, presumably processed in a feed-forward fashion, no such interactions occurred but high-frequency interactions (gamma, 20-100 Hz) were observed. Thus corticocortical synchronization reflects the internal state of the animal and may mediate top-down processes.