Severe stress harmful to children's brain: study
Xinhua News Agency - March 04, 2007

LOS ANGELES, Mar 4, 2007 (Xinhua via COMTEX) -- Severe stress can
affect children's brain development, according to U.S. researchers.

Children with post-traumatic stress disorder and high levels of the
stress hormone cortisol were likely to experience a decrease in the
size of the hippocampus, a brain structure important in memory
processing and emotion, said researchers at the Stanford University
School of Medicine and Lucile Packard Children's Hospital

The children in the study were suffering from post-traumatic stress
disorder, or PTSD, as a result of undergoing physical, emotional or
sexual abuse, witnessing violence or experiencing lasting separation
and loss. This type of developmental trauma often impairs the child's
ability to reach social, emotional and academic milestones.

The researchers studied 15 children from age 7 to 13 suffering from
PTSD. They measured the volume of the hippocampus at the beginning and
end of the 12- to 18-month study period.

After correcting for gender and for physiological maturity, they found
that kids with more severe PTSD symptoms and higher bedtime cortisol
levels (another marker of stress) at the start of the study were more
likely to have reductions in their hippocampal volumes at the end of
the study than their less-affected, but still traumatized peers.

"We know, for example, that these children are at higher risk of
developing depression and/or anxiety as adults," said child
psychiatrist Victor Carrion.

Carrion, assistant professor of child and adolescent psychiatry at the
medical school and director of Stanford's early life stress research
program speculated that cognitive deficits arising from stress
hormones interfere with psychiatric therapy and prolong symptoms.

"We'd really like to understand why some children are more resilient
than others, and what the long-term effects of extreme stress are,"
said Carrion.

Children predisposed by genetics or environment to be more anxious
than their peers are also more likely to develop PTSD in response to
emotional trauma, perhaps because their responses to other life
experiences simply left them closer to that threshold than less-
anxious children, according to the study to be published in the March
issue of Pediatrics.

Although similar effects have been seen in animal studies, this is the
first time the findings have been replicated in children.

Copyright 2007 XINHUA NEWS AGENCY.