e , dACC task selectivity gradually weakened and began later than

e., dACC task selectivity gradually weakened and began later than lPFC) with more trials using the same rule associations. This pattern would seem to be consistent with a role for dACC in control signal specification, and for lPFC in maintenance of the control signal in the service of regulation. Another recent study has provided even finer-grained evidence for a dissociation between the specification and regulation functions of control. Measuring local field potentials (LFPs) in both the dACC and lPFC of macaques, Rothé and colleagues (2011) showed that transient increases

in the high-gamma LFP within dACC signaled salient events (errors and first correct feedback; see also Quilodran et al., 2008), that were followed shortly by more sustained responses in lPFC. Moreover, while high-gamma activity was always correlated between the two regions, the lag in activity between them was LY294002 only found for feedback during search periods and not when the animal was allowed to repeat the behavior for the same reward. see more This is consistent with the engagement of dACC in response to events calling for a re-evaluation and specification of the control signal, and the engagement of lPFC for the representation and maintenance of that signal once specified, in the service of regulating controlled behavior. Despite the challenges involved, some

human imaging studies have also produced evidence for dissociations of responses in dACC and lPFC. For example, MacDonald and colleagues (2000) showed that dACC was more sensitive to response conflict and less MTMR9 so to the implementation of task set instructions, whereas the reverse was true for lPFC. Furthermore, while many studies have found that activity in dACC is consistently associated with the occurrence of an event that triggers adaptive responding, activity in lPFC appears to be more closely associated with the adaptations that

occur after such events (e.g., Egner and Hirsch, 2005a, Egner and Hirsch, 2005b, Kerns, 2006 and Kerns et al., 2004). Additional evidence for this dissociation comes from the study by Kouneiher and colleagues (2009), in which participants switched between two task rules. While the authors found that regions of dACC tracked the incentives for control, they found that lPFC discriminated the task required for the current trial. Furthermore, functional connectivity analyses showed that the connectivity between dACC and lPFC varied with incentive level. The findings above are largely consistent with the division of labor between dACC and lPFC proposed by the EVC model, but they are not definitive. One alternative is that topographic dissociations exist within dACC itself, such that some subregions support specification and others regulation. Consistent with this possibility, findings both from humans (Orr and Weissman, 2009) and macaques (Kaping et al.

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