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bioRxiv · 10.1101/2021.01.23.427916

Long range, high-gamma phase coherence in the human brain during overt and covert speech

Valiante, T.·Garic, B.
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Abstract

Using intracranial electroencephalography (iEEG) in patients undergoing diagnostic workup for epilepsy, we show that during reading, phase coherent high-gamma activity emerges between spatially distant regions of proven involvement in vocalization. Using the novel metric of "phase-dependent power-causal correlations", causal interactions were shown to be maximal at high-gamma frequencies, and displayed stronger correlations to power fluctuations near the optimal time delay, with this delay potentially accounted for by axonal conduction. We conclude that high-gamma activity may represents propagated, directed, large-scale integration between task related regions of the human brain.

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Valiante, T., Garic, B.. 2021-01-23. Long range, high-gamma phase coherence in the human brain during overt and covert speech. https://doi.org/10.1101/2021.01.23.427916

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