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Top-down processing mediated by interareal synchronization.

A von Stein·C Chiang·P König
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Abstract

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.

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AnimalsBehavior, AnimalCatsPhotic StimulationVisual CortexVisual PerceptionJournal ArticleResearch Support, Non-U.S. Gov't

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A von Stein, C Chiang, P König. 2000-12-19. Top-down processing mediated by interareal synchronization.. https://doi.org/10.1073/pnas.97.26.14748

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