[Eeglablist] channel cross-coherence

[Kline, Keith A]

Regarding the channel cross-coherence function:
Does "coherence" represent synchronous changes in signal *amplitude* between two channels, or something else?  Since any two signals containing X Hz activity would necessarily show phase coherenece, albeit with an phase offset (as plotted in the lower graph), I am assume the function's output represents coherently modulated amplitude.  Is this correct? 
Thanks,
Keith