The polarity histogram in relation to the average evoked potential.
It is shown analytically that the polarity histogram (PH) and the average evoked potential (AEP) are linearly related under certain conditions. The relative merits of the two approaches are compared both analytically and by statistical simulation. In general, the PH is a biased estimator of the evoked potential and is less efficient than the AEP, which is unbiased. The PH is more robust against artifact, but this advantage vanishes when conventional artifact rejection is used. The detection of an EP using the PH is problematic. The polarity histogram offers little advantage over signal averaging under typical clinical recording conditions.
D004569:Electroencephalography; D005071:Evoked Potentials; D008433:Mathematics