Abstract

The EEG is traditionally categorized into a handful of different frequency bands (δ, θ, α, β, γ; c.f. Schomer and Lopes da Silva, 2011). This implies that EEG frequencies do not represent an unstruc-tured continuum. But what could be the reasons for that? One obvious reason is that frequency bands such as e.g., θ and α exhibit a clear task and event related behavior (Klimesch, 1999, 2012; Buzsaki, 2006). But here the emphasis is on a for-mal aspect, which is to avoid unwanted “spurious ” phase synchronization. If the numerical ratio between two frequencies (f1, f2; f1 < f2) is harmonic (f2 = I ∗ f1;