[Eeglablist] crossf phase coherence

[Brian Roach]

EEGlab users,

I am wondering about the lower panel in a channel or component cross 
coherence time frequency plot.  The lower panel presents the coherence 
phase difference with the default settings.  My question is whether phase 
coherence here reflects two EEG tracings -- namely an assessment of the 
degree that there is a consistent phase difference of one signal versus the 
other.  Alternatively the two signals could be combined as a single bipolar 
tracing with phase determined relative to the onset of the signaled 
events.  This definition would determine the degree that the bipolar 
tracing demonstrates a consistent phase relative to event onset.  Does 
EEGlab do the first or second process when pop_crossf() or crossf() is called?

thanks,
Brian