We further note that no potential is measured between any two sites if the dipole orientation and location affects both recording sites equally (e.g., both sites are located on the same isopotential line), regardless of dipole strength. Of course, a zero potential is also measured if there is no underlying dipole. Importantly, because no inactive, silent, quiet or infinite recording site exists anywhere on body (cf. Nunez and Srinivasan, 2006; Kayser and Tenke, 2010), the choice of using one recording site as the reference for another is inherently arbitrary, and this arbitrariness is not resolved by employing a consensus for an EEG reference (i.e., nose, linked-mastoids or -ears, and average reference are commonly used).1 EEG measures, or surface potentials (SPs), cannot be understood in isolation from their reference.
