Based on a priori interest in reward, anatomical 5mm-diameter spherical masks for NAcc were created as specified in Bjork et al (2008a) using MarsBaR (Brett et al., 2002). Figure 1 illustrates mask location: the ventromesial intersection of caudate and putamen (Bjork et al., 2008b). Visual inspection of each dataset confirmed masks were accurately placed on NAcc, repositioning up to 1mm ensured accurate placement. NAcc activations were extracted from each individual’s contrast images using MarsBaR. A post-hoc ANOVA (hemisphere x FH x valence x amount) was used to evaluate effects on activation.
