The results concerning the spread of band-limited LFP signals were unexpected, given the relatively lower amplitude of higher frequency signals, and weaker coherence of higher frequency bands between loci (e.g., Maier et al., 2010). However, contrary to general belief that high frequency bands simply do not spread as far as lower frequency signals, our data indicate that band-limited signals over a wide frequency range spread as far as the full-band signals. These results seem at odds with the idea that long range volume conduction itself is limited to lower frequencies, but so does the fact that high frequency signals can be detected in event-related potentials at epidural brain surface (Edwards et al., 2005; Mukamel et al., 2005) and scalp (Schneider et al., 2011). It is worth noting that expressions given for the relationship between CSD and LFP have no dependence on frequency components of signals. Accordingly, all frequency bands in a signal should be volume-conducted equally. Several considerations may help reconcile the “preferential” and “egalitarian” views on volume conduction. First, in keeping with the universally-observed “1/f” power distribution, local generation
