Localized or diffuse: the link between prefrontal cortex volume and cognitive reappraisal.

Despite functional brain imaging research pointing to the role of prefrontal cortex in cognitive reappraisal, the structural correlates of habitual engagement of reappraisal are unclear. Functional imaging studies of reappraisal have shown broad engagement of bilateral middle frontal cortex (MFC) and left superior frontal cortex (SFC), and specific engagement of the right SFC. However, volumetric studies have not identified clear associations between reappraisal and these regions. This discrepancy between functional and structural studies suggests that broad functional engagement associated with reappraisal might not be detectable at a structural level using highly localized volumetric measures. This study addressed the discrepant structural findings by assessing the relation between reappraisal and grey matter volume, using methods that allow both region-level broad/diffuse assessments (surface-based morphometry), and voxel-level specific/localized (voxel-based morphometry) measures. Results were consistent with diffuse positive volumetric associations with reappraisal in the right MFC and left SFC, and a localized positive volumetric association in the right SFC, thus resolving the discrepancy between functional and structural studies. This study provides novel evidence supporting the idea that functional engagement related to transient manipulations of reappraisal can be linked to structural associations related to habitual engagement of similar operations, within the same brain regions.