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 of LFPs as indexed by CSD analysis yields weaker strength at higher frequency bands (Lakatos et al., 2005, 2007). We can speculate that although generally weak, high frequency band signals spread as far as stronger low frequency band signals, with attenuation over distance, lower frequency signals are more reliably detected at longer distances from the generator site. Additionally, a given small temporal variation in signals affects coherence more dramatically in high than in low frequency signals. That would account for the observation that better coherence seen for lower frequency bands over distance (Leopold et al., 2003; Maier et al., 2010).
