The neuroimaging studies had findings in the same
direction as the EEG studies. The MRI study by Yoon
et al.13 reported volume loss in the left middle frontal
gyrus, bilateral anterior insula, and right subgenual
ACC and lower mean diffusivity in white matter regions,
whereas FDG-PET revealed hypometabolism in the left
and right medial frontal gyrus. Atrophy of the DLPFC
has been associated with chronic pain conditions in
several studies.27–29 This area of the brain governs the
balance between the descending fascilatory systems and
descending inhibitory systems, which actively control
the perception of pain