Goal-directed behavior relies on maintaining relevant goalsin working memory (WM) and updating them when required.Computational modeling, behavioral, and neuroimaging workhas previously identified the processes and brain regionsinvolved in selecting, updating, and maintaining declarativeinformation, such as letters and pictures. However, the neuralsubstrates that underlie the analogous processes that operateon procedural information, namely, task goals, are currentlyunknown. Forty-three participants were therefore scanned withfMRI while performing a procedural version of the referencebackparadigm that allowed for the decomposition of WMupdating processes into gate-opening, gate-closing, task switching,and task cue conflict components. Significant behavioralcosts were observed for each of these components, withinteractions indicating facilitation between gate-opening andtask switching, and a modulation of cue conflict by gate state.In neural terms, opening the gate to procedural WM was associatedwith activity in medial pFC, posterior parietal cortex(PPC), the basal ganglia (BG), thalamus, and midbrain, but onlywhen the task set needed to be updated. Closing the gate toprocedural WM was associated with frontoparietal and BG activityspecifically in conditions where conflicting task cues had tobe ignored. Task switching was associated with activity in themedial pFC/ACC, PPC, and BG, whereas cue conflict was associatedwith PPC and BG activity during gate closing but wasabolished when the gate was already closed. These resultsare discussed in relation to declarative WM and to gatingmodels of WM.
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