When you’re in constant pain, it can be hard to think of anything else. The pain clouds your thoughts like a fog, wearing away at your patience and your attention. New research, however, suggests that when relief does finally come, your brain can recover all the way down to a cellular level.

A report in the May 18 Journal of Neuroscience finds that relieving chronic lower back pain correlates with a return to normal brain function. Fourteen patients performed a cognitive task before and after one of two treatments, either spinal surgery or an injection of anesthesia between spinal joints. The cognitive task, which tested patients’ ability to focus, involved picking out which of three numbers or letters didn’t belong in a group.

Among those who felt pain relief after treatment, neural activity during the task improved to healthy levels in the dorsolateral prefrontal cortex, a brain region associated with attention. More striking, the cortex had actually become thicker, attaining a thickness similar to that of healthy individuals.

Previous research has suggested that chronic pain leads to a loss in volume of gray matter, and potentially function,in several brain regions. Laura Stone, lead author of the current study and a researcher at McGill University, said she expected a slowdown, not a reversal, of these kinds of losses. The dorsolateral prefrontal cortex is a particularly interesting area because it’s also associated with decision-making, anxiety, depression and emotion.

“There’s something special about the emotional aspects of recovery from pain,” Stone said.

David Seminowicz, another study author and an assistant professor at the University of Maryland School of Dentistry, said he plans to try other pain treatments and evaluate their effects on brain function.For example, cognitive-behavioral therapy and meditation are being considered by researchers.

Stone said future studies might also look at the cellular basis for cortex recovery. The brain, rather than the back, would become the target for therapy.