Stress affects your memory? interesting article...
Stress Hampers Memory Retrieval
NEW YORK, Aug 19 (Reuters) -- Feeling stressed out? It may have an impact on your memory. According to a study in rats, a stress-induced surge of hormones known as glucocorticoids may inhibit the retrieval of memories.
The findings may explain why some students who study hard may have a difficult time remembering material under the stress of test taking, according to researchers from the Center for the Neurobiology of Learning and Memory at the University of California, Irvine. Glucocorticoids have long been known to interfere with memory consolidation, or the transfer of memories from short-term to long-term storage in the brain.
"To our knowledge, our report in the first to demonstrate that once memories are consolidated, the efficacy or accuracy of the information retrieved remains vulnerable to glucocorticoids at the time of recall," wrote lead author Dr. Dominique J.-F. de Quervain and colleagues.
In the study, the researchers trained rats to swim through a water maze to a platform. But when the trained rats were stressed by a mild electrical shock 30 minutes before being put in the water, they had difficulty locating the platform. In contrast, the researchers found that if the shock was given 2 minutes or 4 hours before the test, the animals had no difficulty swimming the maze, according to the report in the August 20th issue of Nature.
This impairment in performance coincides with high blood levels of a glucocorticoid hormone known as corticosterone, which reach a peak about 30 minutes after a stressful incident, explain the researchers. Blocking the hormone with a drug "blocks the stress-induced retention impairment," according to the report.
The finding was backed up by the results of another part of the study. The researchers found that administering corticosterone to unstressed rats 30 minutes prior to testing also resulted in impaired performance similar to that seen in the rats given a shock.
According to a statement issued by the Center, the study results contribute to knowledge of how physical and emotional states can affect memory recall, and how stress triggers survival behaviors.
"It you are in a stressful situation, it's not important to remember things like two plus two equals four -- the most important thing is to run away," said co-author Benno Roozendaal.
Future research planned at the Center "will further explore the brain mechanisms involved in stress and long-term memory retrieval," according to the statement.
SOURCE: Nature 1998;394:787-790.
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