While these findings support P3-AR’s potential as an endophenotype for EXT psychopathology, at least for males, there is evidence that the P3 ERP is composed of multiple neurophysiological processes (e.g. Dien, Spencer, & Donchin, 2003; Mantini, Corbetta, Perrucci, Romani, & Del Gratta, 2009). An emerging methodological approach that serves to represent the ERP in a more detailed way than standard measures (e.g. peak amplitude), and endeavors to delineate these multiple processes is time-frequency (TF) decomposition. For instance, TF decomposition has been used to show that ERP activity during the P3 can be characterized by TF components in the delta (0–3 Hz) and theta (3–7 Hz) frequency bands (Basar-Eroglu, Basar, Demiralp, & Schurmann, 1992; E. M. Bernat, Malone, Williams, Patrick, & Iacono, 2007; Jones et al., 2006; Yordanova, Devrim, Kolev, Ademoglu, & Demiralp, 2000), suggesting that TF representations may present a more detailed characterization of event-related brain activity.
