By definition, volume conduction requires zero phase lag, but a phase difference close to zero is not necessarily due to volume conduction, as this kind of phase associations can be found widespread over the cerebral cortex because of corticothalamic
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5-9 Hz oscillations are more pro-epileptogenic than sleep spindles in rats.
In the 1990's there was consensus that the neurons in the nuclei reticularis thalami (nrt) "gated"' information in the corticothalamic