Studies have further demonstrated that delta and theta EROs are the primary contributors to the human P3 ERP component (Basar et al., 1999; Basar-Eroglu et al., 1992; Demiralp et al., 2001; Karakas et al., 2000; Schurmann et al., 2001). Reductions in P3 amplitude have been related to decreased cortical ERO energy and also to higher phase variability and weaker phase locking. For instance, it has been shown that the reduction of P3 amplitude during retrieval of a working memory task is associated with a decrease in delta ERO power and an increase in phase variability (Schack and Klimesch, 2002). In addition to their role in generating the P3 ERP component, evoked oscillations have also been shown to play a role in the generation of other ERP components, including the P1-N1 complex. There is evidence to suggest that alpha and theta evoked power and phase locking (PL) plays an important role in the generation of the P1-N1 complex (Klimesch et al., 2004). However, whether differences in ERO energy and phase variability play a role in the different neurophysiological profiles identified in animal models has been less studied
