Stress may be harmful at first, but in the end, people recover from it.

A study published in the journal Proceedings of the National Academy of Sciences analyzed 33 Dutch soldiers deployed to Afghanistan for 4 months for the first time. Researchers compared these soldiers to 26 soldiers who were not deployed.

The soldiers who were deployed were armed in combat and experienced enemy fire, but this did not appear to aggravate stress symptoms, such as PTSD, anxiety, or mood among them. Despite this, the participants showed marked brain differences.

The combat group displayed reduced functioning and damaged structure in the midbrain, and performed worse on cognitive tests than those who were not deployed. This was seen less than 2 months after they returned.

But a year and a half later, researchers discovered that the deployed soldiers had generally returned to normal in regards to brain structure and cognitive performance.

Although some performance may still suffer, a new brain function is enhanced. Amygdala, a part of the brain for detecting danger, heightened activity in returning soldiers.

“It makes sense that soldiers would benefit from time to recuperate in between deployments, so that the brain can re-adapt to a non-combat situation,” says Guido van Wingen of the Brain Imaging Center in Amsterdam. “What the results collectively show is the brain is able to restore (itself) from the adverse effects of stress, if you give it at least enough time.”

Make sure to consult your doctor if you are experiencing chronic pain or any other types of stress.