Navigation Links
Short stressful events may improve working memory
Date:7/23/2009

BUFFALO, N.Y. -- Experiencing chronic stress day after day can produce wear and tear on the body physically and mentally, and can have a detrimental effect on learning and emotion. However, acute stress -- a short stressful incident -- may enhance learning and memory.

Researchers at the University at Buffalo have shown, in trials using rodents as an animal model, that acute stress can produce a beneficial effect on learning and memory, through the effect of the stress hormone corticosterone (cortisol in humans) on the brain's prefrontal cortex, a key region that controls learning and emotion.

Specifically, they demonstrated that acute stress increases transmission of the neurotransmitter glutamate and improves working memory.

"Stress hormones have both protective and damaging effects on the body," said Zhen Yan, professor of physiology and biophysics at UB and senior author on the study. "This paper and others we have in the pipeline explain why we need stress to perform better, but don't want to be stressed out."

The study appeared July 20 in the online edition of Proceedings of the National Academy of Sciences and will be published in an upcoming print version of the journal. Eunice Y. Yuen, Ph.D., UB research assistant professor of physiology and biophysics, is the first author on the study.

To test the effect of acute stress on working memory, Yan, Yuen and colleagues trained rats in a maze until they could complete it correctly 60-70 percent of the time. When the rodents reached this level of accuracy for two consecutive days, half were put through a 20-minute forced swim, which served as acute stress, and then were put through the maze again.

Results showed that the stressed rats made significantly fewer mistakes as they went through the maze both four hours after the stressful experience and one day post-stress, compared to the non-stressed rats.

To determine if the corticosterone neuropathway was responsible for the improved memory, as they proposed, researchers injected one group of rats before the stressful forced-swim with a medicinal compound that blocks the pathway, and injected another group with saline. Results showed that the saline group, in which the corticosterone neuropathway was not blocked, performed better in the maze than the blocked group.

The researchers also determined that the stressful experience did not increase depression or anxiety-related behavior in the animals.

"It is known that stress has both positive and negative actions in the brain, but the underlying mechanism is elusive," said Yan. "Several key brain regions involved in cognition and emotions, including the prefrontal cortex, have been identified as the primary target of corticosteroid, the major stress hormone.

"Our current study identifies a novel mechanism that underlies the impact of acute stress on working memory, a cognitive process depending on glutamate receptor-mediated excitatory signals in prefrontal cortex circuits."

The investigators have expanded this research in several directions. In a paper currently under review, they have identified the key signaling molecules that link acute stress to the enhancement of glutamate receptors and working memory.

"In addition," noted Yan, "we have discovered that chronic stress suppresses the transmission of glutamate in the prefrontal cortex of male rodents, which is opposite to the facilitating effect of acute stress, and that estrogen receptors in female rodents make them more resilient to chronic stress than male rats.

"All these studies should bring new insights into the complex actions of stress in different circumstances that may be applicable to humans in the future," she said.


'/>"/>

Contact: Lois Baker
ljbaker@buffalo.edu
716-645-4606
University at Buffalo
Source:Eurekalert

Related biology news :

1. Study suggests genetic connection between short stature and arthritis
2. Living fossils have long- and short-term memory
3. Big cats, wild pigs and short-eared dogs -- oh, my!
4. Shorter wait means longer life for kidney transplant candidates
5. Some short-term memories die suddenly, no fading
6. Shortcuts of the mind lead to miscalculations of weight and caloric intake, says Penn study
7. Implanting embryonic cardiac cells prevents arrhythmias
8. Device prevents potential errors in childrens medications
9. A compound extracted from olives inhibits cancer cells growth and prevents their appearance
10. Vobile Launches VideoDNA Live; Enables Real-Time Digital Content Protection for Live Broadcast Events
11. Chemical compound prevents cancer in lab
Post Your Comments:
*Name:
*Comment:
*Email:
(Date:6/21/2016)... , June 21, 2016 NuData ... the new role of principal product architect and ... the director of customer development. Both will report ... technical officer. The moves reflect NuData,s strategic growth ... response to high customer demand and customer focus ...
(Date:6/9/2016)... 9, 2016  Perkotek an innovation leader in attendance control systems is proud to ... hours, for employers to make sure the right employees are actually signing in, and ... ... ... ...
(Date:6/2/2016)... 2, 2016 The Department of Transport ... the 44 million US Dollar project, for the , ... including Personalization, Enrolment, and IT Infrastructure , to ... production and implementation of Identity Management Solutions. Numerous renowned international ... Decatur was selected for the most compliant ...
Breaking Biology News(10 mins):
(Date:6/27/2016)... NC (PRWEB) , ... June 27, 2016 , ... ... mission to bring innovative medical technologies, services and solutions to the healthcare market. ... and implementation of various distribution, manufacturing, sales and marketing strategies that are necessary ...
(Date:6/24/2016)... June 24, 2016 Epic Sciences unveiled ... cancers susceptible to PARP inhibitors by targeting homologous ... (CTCs). The new test has already been incorporated ... multiple cancer types. Over 230 clinical ... response pathways, including PARP, ATM, ATR, DNA-PK and ...
(Date:6/23/2016)... , June 23, 2016   Boston ... of novel compounds designed to target cancer stemness ... has been granted Orphan Drug Designation from the ... treatment of gastric cancer, including gastroesophageal junction (GEJ) ... inhibitor designed to inhibit cancer stemness pathways by ...
(Date:6/23/2016)... 23, 2016  The Prostate Cancer Foundation (PCF) is pleased to ... faster cures for prostate cancer. Members of the Class of 2016 were selected ... Read More About the Class of 2016 PCF Young Investigators ... ... ...
Breaking Biology Technology: