Our finding that decreased current density in the ORP time frame at cingulate gyrus can be further supported and explained in the light of relevant findings in the literature. For example, neuroimaging studies of reward processing have identified a number of brain areas that are activated by the delivery of primary reinforcers such as appetitive stimuli (Berns et al., 2001; McClure et al., 2003; O’Doherty et al., 2001), as well as secondary reinforcement such as monetary gains and losses (Breiter et al., 2001; Delgado et al., 2004; Elliott et al., 2000; Holroyd et al., 2004; Thut et al., 1997, as cited from Nieuwenhuis et al., 2005a). Increasing evidence supports the integral role of the ACC in performance monitoring, especially involving predictability of an outcome (Paulus et al., 2002, 2003, 2004), which are critical in regulating various relevant social behaviors. Subdivisions within the ACC have specialized functions: i) the dorsal (pregenual) region of the ACC may be involved in cognitive aspects of decision making, including reward based decision making, error monitoring, anticipation, working memory, motor response, and novelty detection (Bush et
