Top-down control of cortical gamma-band communication via pulvinar induced phase shifts in the alpha rhythm
Fig 3
The alpha drive from the pulvinar modulates gamma power in a phasic manner.
(A,B) The alpha modulation from the pulvinar drive to the I-cells is clearly visible in both (A) the rastergram and (B) the STH. (C) The power spectral density of the E-cell STH had peaks both in the alpha and gamma band. Data was averaged over 10 trials, the shaded areas represent the standard error of the mean (SEM). (D) The gamma power was modulated by the phase of the alpha oscillation. Top: The spectrogram obtained via a wavelet analysis. Bottom: The gamma power (20–50 Hz; green line) is locked to the phase of the modulating alpha oscillation (blue line). (E) The gamma power (green line) follows the peak activity of excitatory neurons (red line), whereas the peak for the inhibitory neuronal firing (blue line) is approximately out of phase with gamma power. Data was averaged over 10 trials, the error bars represent the standard error of the mean (SEM).