Severe stress can change the structure of a child’s brain, a new study finds, potentially limiting the child’s ability to cope with the crisis. Levels of the hormone cortisol are known to rise with stress, and past studies in adults have suggested an association between higher emotional stress and a smaller hippocampus – a brain region closely connected to the emotion center and involved with memory storage and processing. A group of researchers led by Dr. Victor Carrion from Stanford University looked at the brain structures and bedtime cortisol levels of 15 children, ages 7 to 13, who were suffering from post-traumatic stress disorder. Twelve to 18 months later, participants were assessed again, and researchers found that hippocampus volumes were reduced more in children with more severe stress symptoms and higher bedtime cortisol levels. Because the hippocampus is so important in memory and emotion processing, researchers think that its reduced volume will lower a child’s coping ability. This, in turn, will raise stress and cortisol levels, further damaging the hippocampus and continuing the vicious cycle.

BOTTOM LINE: Dr. Carrion said that current psychiatric therapies may work less well in children with post-traumatic stress disorder because of their compromised coping abilities. “We need to develop more focused therapeutic interventions that take this into consideration,” he said.

WHAT’S NEXT: The researchers want to see if the functional ability of the hippocampus is also reduced over time by high cortisol levels.

CAUTIONS: This is a small pilot study. More and larger studies are required to confirm its findings. The study does not compare brain structure before and after trauma, or between children with and without post-traumatic stress disorder.
WHERE TO FIND IT: Pediatrics, March 2007
SENA DESAI GOPAL