“…This perspective is consistent with a large number of previous AP studies that adopted overt paradigms and reported reduced or even absent P300 amplitudes in AP participants (Crummer et al, 1994;Hantz et al, 1992;Wayman et al, 1992;Klein et al, 1984). Further evidence for the involvement of cognitive mechanisms in AP participants arises from labeling tasks, as manifested by a reduction in the P3b component, a reduction in the posterior positive and anterior negative slow waves (Itoh et al, 2005), or by increased N400 and LPC responses (Elmer, Sollberger, et al, 2013). Overall, the reduced P3a amplitudes in our study can be explained as decreased susceptibility among AP participants responding to tones, suggesting more efficient and parsimonious cognitive processing (Bendixen et al, 2010;Wetzel & Schröger, 2007;Wetzel, Widmann, Berti, & Schröger, 2006;Berti et al, 2004;Roeber, Berti, & Schröger, 2003;Gumenyuk et al, 2001;Escera, Alho, Winkler, & Näätänen, 1998;Schröger & Wolff, 1998).…”