Recent studies involving time-frequency domain analysis have determined that ERPs may not be unitary entities but arise from phase resetting or superposition of different frequency bands in various regions of the brain [Basar et al., 2001a; Makeig et al., 2002; Gruber et al., 2005]. These underlying neural phenomena, referred to as event-related oscillations (EROs), appear to influence the timing of brain activity and synchrony in networks of active neurons, and thus are likely to represent a basic mechanism of neural communication and integrative brain functions [Basar et al., 1999, 2001a; Fries, 2005; Buzsaki, 2006].
