Back home   |   Bookmark   |   Start page   |   Site map    
Services
News
Channels
Home & Family
Leisure
Technology
Business
Science
Site Search
Free email




Short-term stress can affect learning and memory

TheAllINeed.com
(NC&T/UCI) It has been known that severe stress lasting weeks or months can impair cell communication in the brain's learning and memory region, but this study provides the first evidence that short-term stress has the same effect. The study appears in the March 12 edition of the Journal of Neuroscience.

"Stress is a constant in our lives and cannot be avoided," said Dr. Tallie Z. Baram, the Danette Shepard Chair in Neurological Sciences in the UC Irvine School of Medicine and study leader. "Our findings can play an important role in the current development of drugs that might prevent these undesirable effects and offer insights into why some people are forgetful or have difficulty retaining information during stressful situations."

In their study, Baram and her UC Irvine colleagues identified a novel process by which stress caused these effects. They found that rather than involving the widely known stress hormone cortisol, which circulates throughout the body, acute stress activated selective molecules called corticotropin releasing hormones, which disrupted the process by which the brain collects and stores memories.

Learning and memory take place at synapses, which are junctions through which brain cells communicate. These synapses reside on specialized branchlike protrusions on neurons called dendritic spines.

In rat and mouse studies, Baram's group saw that the release of CRH in the hippocampus, the brain's primary learning and memory center, led to the rapid disintegration of these dendritic spines, which in turn limited the ability of synapses to collect and store memories.

Tallie Baram. (Photo: UCI)
The researchers discovered that blocking the CRH molecules' interaction with their receptor molecules eliminated stress damage to dendritic spines in the hippocampal cells involved with learning and memory.

In addition, the authors replicated the effects of stress on dendritic spines by administering low levels of synthetic CRH, and watching how the spines retracted over minutes. "Fortunately, once we removed the CRH, the spines seemed to grow back," Baram said.

Baram also noted that there are compounds under development that show the ability to block CRH receptors, and that this study can play a role in the creation of therapies based on these compounds to address stress-related learning and memory loss.

Yuncai Chen, Celine Dubé and Courtney Burgdorff of UC Irvine also participated in the study, which was supported by the National Institutes of Health.


About the Author
©2006 All rights reserved

More articles
Origins of chickens
Detect the snake
Exercise multiple sclerosis
Link between saliva and good and bad bacteria in mouth
Genes, the key of happiness
Drinking influence mortality
To bet
Overweight and exercise
Reaching goals
Short-term stress
Social dominance
Gender differences in language
Memory goes on trial children's testimony may be more reliable
Color vision system
Gene that controls fruit shape
Nature or nurture - why do some of us see red?
Fountain of youth comes in a pill?
Depth-perception mechanism in brain
Risk alzheimers disease in men and women
Protein triggers aggressive cancer
Quotes
And all I have to do is be at home. And that wont be hard - I live at home!
Aaron (your humble moderator)

And dont be tempted to make housecleaning fun. Dont try to dust withthe dog. It might _seem_ like a good idea....
P.J. ORourke into The Bachelor Home Companion

Alcohol and calculus dont mix. Never drink and derive.

Alex, Ill take Things Only I Know for $200


Writers
If you are a writer and want to see your article published at Theallineed.com, just click here to submit.

Info
Today...
In the news...
Hundreds of thousands may need assistance in cyclone-hit Myanmar
Cyclone Nargis, which made landfall in the Irrawaddy delta region on Friday, left thousands of people dead in its wake and hundreds of thousands without shelter.
What would you change about Internet shopping?
Have more sales just like the stores
Offer more incentives like free shipping
Have operators available 24 hours
Wouldn't change anything
Other
 
Things to ponder
Never underestimate the power of stupid people in large groups.

Did you know...
A ten-gallon hat holds about three-fourths of a gallon (2.85 liters).

Quote of the day
Drama is life with the dull bits cut out.
Alfred Hitchcock

Featured article
Effects of excessive alcohol consumption on social environment
Consuming alcohol in the inappropriate times such as, while driving, or operating machines, or in working hours can lead to accidents, loss of work, and may be even more fatal

 
© 2002 - 2007 Lexur