The findings from the third section, that NAcc-aPFC and NAcc-vmPFC overconnectivity in ADHD is associated with impulsive decision, can be linked to one ADHD theory. That theory hypothesized that overactivity of NAcc and its increased signaling to the prefrontal cortex would lead to excessive approach and failure in estimating future consequences, and as a result, impulsivity (Nigg and Casey, 2005). Functional MRI studies in ADHD have found atypical activation of NAcc and OFC (usally overlapping with vmPFC) during reward anticipation and outcome gain, respectively (Plichta et al., 2009; Scheres et al., 2007). The left aPFC cited above was shown to be part of the cingulo-opercular network and is involved in control functions and decision making (Dosenbach et al., 2007). From this point of view, these results suggest that an atypical interaction between a control network and the reward circuit leads to impulsive decision in ADHD.
