Top-down control of cortical gamma-band communication via pulvinar induced phase shifts in the alpha rhythm
Fig 2
Gamma oscillations emerged spontaneously from the reciprocal interaction between E cells and I cells.
(A) Rastergram of excitatory (red) and inhibitory (blue) neurons in one population during an interval of 1000 ms. Gamma oscillations are visible as vertical alignment of spike times. (B) The spike time histogram (STH) reveals the gamma oscillations (bin width Δt = 1 ms) in both excitatory and inhibitory cells. (C) The power spectral density of the E-population STH, showing gamma oscillations between 30 and 50 Hz. Data was averaged over 10 trials, the shaded areas represent the standard error of the mean (SEM). (D) Increasing the input current to excitatory neurons increases gamma power, while increasing input current to the inhibitory neurons decreases gamma power. The current to excitatory cells is varied along the y-direction, whereas that to the inhibitory cells is varied along the x-axis, the resulting gamma power is color-coded according to the color bar shown on the right of the panel. (E) The frequency of the gamma oscillation increases with increasing input to the excitatory as well as the inhibitory neurons.