referential vs bipolar montage

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Pete: I understand how, in a bipolar montage, phase differences between signals at TWO different scalp sites determine the value of the observed amplitude difference. When two signals from two different sites are in phase the observed amplitude DIFFERENCE (ie. C3/C4) DECREASES (they cancel each other:C3-C4) Phase differences might also affect the observed amplitude at a SINGLE scalp site in a referential montage (eg. C3/A1) in the OPPOSITE way. When signals (ie. sine waves) are being trained up it may be that the phase differences among them are being trained down and vice versa for down training. Thus when two signals at the same scalp site are in phase the observed AMPLITUDE (ie C3-A1) INCREASES -- (I think you called the "phase locking" when it gets out of hand). Kind

of suggests that training up in a referential montage might not be a good idea for seizure prone clients esp in fast frequencies eg.SMR). Squishes, Squashes and window squashes only -- just to be on the safe side? nick mammano