The researchers are currently expanding these studies to examine the genetic factors that impact normal brain development, and to map brain changes in a variety of child psychiatric conditions.
Other reports describe the effects of environmental influences that occur during adolescence on later conditions that become apparent in the adult.
Studies by Susan Andersen, PhD, of McLean Hospital in Belmont, Mass., and colleagues show that stressful events experienced during adolescence can lead to enduring changes in brain structure in adulthood. This work is the first to demonstrate that exposure to a significant stress during adolescence can impact neuronal connections in the adult brain.
The researchers found that adult rats exposed to a social stress during adolescence (ages approximating 13 to 15 years in humans) showed a significant decrease in a specific protein found in the hippocampus, a brain region important for learning and memory. In fact, the loss of this protein, synaptophysin, is at least as great as that occurring in animals exposed to more severe stressors at a younger age, suggesting that adolescents may be more vulnerable to the effects of stress than younger animals.
Under typical conditions, synaptophysin, which is often used as an index of the number of neuronal connections, or synapses, reaches a peak during young adulthood (approximately ages 18 to 20), with the rise occurring primarily during adolescence. The team tested whether a social stress during this key developmental period might alter this pattern. A control group of rats was housed with their peers, and an experimental group of rats was housed individually during adolescence; individual housing in normall
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Contact: Dawn McCoy
dawn@sfn.org
202-462-6688
Society for Neuroscience
8-Nov-2003