Brain structural alterations associated with dysfunctional cognitive control of pain in patients with low back pain

Pain-related thought suppression (TS) is the most common cognitive responses to pain. Previous research has shown that TS has paradoxical effects that may increase the awareness of pain. But, the relationship between pain-related TS and structural brain alterations is unknown. Therefore the results of this study provide the potential insights into the neural substrates of obstructive cognitive control in chronic low back pain, with a particular emphasis on pain-related TS.  

The chronic back pain (CBP) may lead to functional disability in the circuitry underlying the cognitive control of pain as per the recent evidence. One of the common types of cognitive control of pain is the thought suppression (TS). This approach displays the paradoxical effects that may increase the awareness of pain as per the previous researches. Pain-related TS may also enhance individuals' attention to pain, which may also develop pain sensation, but therefore far, the association between structural brain alterations and pain-related TS is unexplored.

The study examined 30 patients six months following lumbar disc surgery using voxel-based morphometry (VBM) to recognise brain regions associated with TS scores.

As pain-related TS has been positively associated with depression, all estimations were constrained for age and depression. VBM reported a negative relationship between the TS score and regional grey matter volume (GMV) in the left middle temporal gyrus (L MTG) and the left superior temporal gyrus (LSTG), which is part of the left temporoparietal junction (L TPJ). Further, a mediation analysis exhibited a considerable mediation impact of the pain-related TS on the connection between GMV of the left TPJ and recorded pain severity in the last seven days.

These outcomes are compatible with prior research on the dysfunctional cognitive control of pain and may, consequently, produce possible insights into the neural substrates of obstructive cognitive management in chronic low back pain, with particular stress on pain-related TS.