Finally, it is widely acknowledged that EEG consists of a myriad of oscillations at various frequencies that all serve different functional purposes (Akam & Kullmann, 2014; Klimesch, 1996). EEG is generally separated into oscillation frequency bands that reflect these functional differences; however, the choice of cutoff frequencies separating these bands is generally taken for granted and reflects commonly accepted fixed definitions. For example, where many studies have captured alpha oscillations as a single entity to be analyzed across the 8–12 Hz frequency band (Palva et al., 2013; Smit et al., 2013), many others have used separate upper and lower bands as they found these to be informative for the functional properties investigated (Doppelmayr et al., 2002; Klimesch et al., 1997; Stam, 2000). Arguably, a frequency band definition can be performed in a more bottom‐up fashion, using the data to optimize information content in the frequency band definition. For our upcoming functional connectivity project, we have used such an approach. The Box 1 below explicates how this analysis was performed, with further specifics provided in the supplementary information. By using this
