Shape shifting pain: chronification of back pain shifts brain representation from nociceptive to emotional circuits.
Studies indicate that people with chronic pain conditions exhibit changes in brain activity and function compared to healthy subjects with acute pain. The aim of this study was to examine these changes in brain activity during the transition from (sub) acute back pain (SBP) to chronic back pain (CBP).
Back pain related brain activity were measured using brain scans (MRI) and compared between subjects who had back pain <2 months (n=94) to subjects with chronic back pain >10 years (n=59). Functional areas of interest were determined (Pain, emotion and reward), and masks were used to compare brain activity to the areas associated with these terms.
The results suggest that in the transition from SBP to CBP, the brain undergoes large shifts in brain activity. With the chronification of back pain, brain activity transforms from the pattern associated with ‘pain’ to that associated with the term ‘emotion’.
Implication and considerations: The brain maps should not be interpreted as a unique relationship. There is considerable overlap between these circuits and they are associated but not limited to terms such as pain, emotion and reward. However, novel insights are given regarding the transition from acute- to chronic pain. > From: Hashmi et al., Brain 136 (2013) 2751–2768. All rights reserved to Oxford University Press.
The free full text article can be found here.