Instantaneous Granger Causality with the Hilbert-Huang Transform
Figure 9
ISGC based on the standard cross-spectrum is computed for each time point. Spectral resolution was set to 0.5 Hz for visualization effects. Positive values of ISGC from time series 1 to 2 at 20 Hz can be observed until 0.5 seconds and at 36 Hz from 0.5 to 1 seconds. Spurious causality 2→1 is also present in lower frequencies.
