Chronic Pain Forces the Brain to Work Overtime

Fatigue is a well-known companion to chronic pain, but the mental side of this exhaustion has been less understood. A recent study has shed light on this “cognitive fatigability” using functional magnetic resonance imaging (fMRI).

Researchers asked women with chronic pain and a healthy control group to perform a 20-minute reaction-time task. The results were telling: while healthy participants maintained steady performance, those with chronic pain showed a significant decline in their reaction times over the course of the task.

Brain scans revealed different patterns of organisation. The chronic pain group showed stronger activation in brain regions linked to motor and cognitive control. Researchers suggest this may be a compensatory mechanism—the brain working overtime just to keep up. In contrast, the healthy controls showed more activity in areas associated with motivation and efficient decision-making. The findings offer a potential neurological basis for the mental exhaustion reported by so many people living with chronic pain.