Coherence in EEG
With regard to EEG, coherence is {{c1:: a squared correlation coefficient that estimates the consistency of relative amplitude and phase between any pair of signals in each frequency band. Any pair of EEG signals may be coherent in some frequency bands and incoherent in others.}}
Coherence provides one important estimate of functional interactions between neural systems operating in each frequency band, and may yield information about network formation and functional integration across brain regions.
Spectral coherence refers to the coherence across a power spectrum of a time series, which shows the intensity or relative power of a certain frequency averaged across temporal data.