2011a) as well as at rest (de Pasquale et al., 2010; Brookes et al., 2011b). However, a more physiologically oriented probe on brain functional connectivity can be identified by phase-based metrics under the CTC hypothesis (Fries, 2005), that states that only coherently oscillating neuronal groups can interact effectively. Thus, MEG can be an ideal tool to assess functional connectivity by investigating the phase relationship between two (possibly) interacting areas. This approach will be discussed extensively in the following section.
