Narrator: This is Science Today. Researchers are looking into how stressful, early life experiences can influence brain function later in life. Dr. Tallie Z. Baram, a professor of anatomy and neurobiology at the University of California, Irvine has found that stress induced in rat pups releases a neuropeptide called corticotropin-releasing hormone, or CRH. This caused lower cognitive function in learning and memory later in life by shrinking dendritic spines - areas of the neuron where synapses take place.

Baram: Essentially in controlled situation without CRH, the number of new spines and the number of retracting spines stays about balanced so we don't lose anything. However, when you put in CRH for thirty minutes, the retraction of spines was markedly enhanced without really any change in formation of new ones. So, the total number of spines, the connections where memories can be formed, reduced.

Narrator: But when the researchers used a receptor to block CRH, the effects were reversed.

Baram: The whole point here is that if we really go deep and understand the mechanism, we can use this mechanism to treat.

Narrator: For Science Today, I'm Larissa Branin.