Featured Research

from universities, journals, and other organizations

New cause of cognitive decline in aging population discovered in nerve cell specializations

Date:
June 2, 2010
Source:
The Mount Sinai Hospital / Mount Sinai School of Medicine
Summary:
Researchers have found that certain types of specializations on nerve cells called "spines" are depleted as a person ages, causing cognitive decline in the part of the brain that mediates the highest levels of learning. These spines receive an important class of synapses that are involved with the process of learning.

Researchers at Mount Sinai School of Medicine have found that certain types of specializations on nerve cells called "spines" are depleted as a person ages, causing cognitive decline in the part of the brain that mediates the highest levels of learning. These spines receive an important class of synapses that are involved with the process of learning. The discovery provides the medical community with a new therapeutic target to help prevent this loss of function.

Related Articles


The study is published in the June 2 issue of the Journal of Neuroscience.

"We know that when we age, we lose certain spines, but we did not know which ones and how their loss impacted cognition," said John H. Morrison, PhD, Dean of Basic Sciences and the Graduate School of Biological Sciences and Professor of the Department of Neuroscience, Mount Sinai School of Medicine. "This study shows which spines are lost and what their impact is on brain function, giving us a foundation to research treatment interventions to protect against age-related cognitive decline."

The research team was led by Dr. Morrison and Peter R. Rapp, PhD, Adjunct Professor of Neuroscience at Mount Sinai School of Medicine, with Dani Dumitriu, MD/PhD student and Dr. Jiandong Hao, Adjunct Assistant Professor at Mount Sinai School of Medicine as the key investigators on the team and co-first authors of the paper. The team studied six young adult and nine older rhesus monkeys as they participated in a delayed response test. The monkeys watched as food was baited and hidden, and then a screen was put in front of them so they could no longer see the location of the hidden reward.

At the beginning of the test, the screen was raised immediately and the monkeys were able to find the food reward right away. The subject's memory was tested by increasing the time that the reward was blocked from view to test if the monkeys retained where the reward was placed over longer intervals of time. Aged monkeys performed significantly worse on the tests than young monkeys, especially as the time intervals increased.

Morrison's team then used microscopic techniques to visualize the spines on nerve cells within the prefrontal cortex, an area of the brain that mediates high level learning. Nerve cells in the prefrontal cortex contain two types of spines: thin, dynamic spines, which are key to learning new things, establishing rules, and planning, and large, mushroom-shaped spines that are very stable and likely mediate long-term memories and highly stable information that we would consider expertise. The researchers determined that the older monkeys lacked the thin spines but retained the larger spines, indicating that the loss of the thin spines may be responsible for the monkeys' inability to learn and retain information during the test. For the first time, the researchers determined that the large spines were stable, which provides a synaptic basis for the observation that expertise and skills learned early in life are often maintained into old age.

"Researchers have long wondered why aging affects our ability to learn and remember new tasks and information, yet we retain well-established information, such as career expertise, well into old age," continued Dr. Morrison. "These data indicate that there is a biological reason why people cannot learn new things at an older age, but can retain knowledge learned years before, such as a professor teaching into his 80s."

Dr. Morrison noted that this study will allow for the development of prevention strategies in youth, such as further emphasis on learning skills and broadening expertise. "The data also provide a foundation for therapies to lessen cognitive decline, through pharmaceutical and lifestyle interventions," he added.

Dr. Morrison and his team have also received funding from the National Institute on Aging (NIA) over the last ten years to study cognitive performance in monkeys undergoing menopause. The funding supports research on whether treatment with estrogen enhances cognitive performance in monkeys after menopause and which synaptic effects of estrogen are critically important for cognitive enhancement.

In future experiments, Dr. Morrison's team will test the idea of a "window of opportunity," to determine whether treatment with hormone therapy needs to be initiated soon after menopause to have the optimal cognitive impact with little risk. The National Institutes of Health (NIH)'s Women's Health Initiative showed that women who took hormone therapy were at increased risk for breast cancer and cognitive decline. However, the data only focused on women who started therapy ten years after menopause. Dr. Morrison's study will evaluate the impact of hormone therapy at the start of menopause on cognition and determine if adverse effect risk is reduced.

"We look forward to continuing to study the impact aging has on cognition and potential ways to reduce that impact," said Dr. Morrison. "While hormone therapy has been controversial in the past, we hope to show that it can provide important cognitive benefits with little risk if initiated within a certain window of opportunity."

The research published in the Journal of Neuroscience was supported through a Merit Award grant that Dr. Morrison received from the NIH.


Story Source:

The above story is based on materials provided by The Mount Sinai Hospital / Mount Sinai School of Medicine. Note: Materials may be edited for content and length.


Cite This Page:

The Mount Sinai Hospital / Mount Sinai School of Medicine. "New cause of cognitive decline in aging population discovered in nerve cell specializations." ScienceDaily. ScienceDaily, 2 June 2010. <www.sciencedaily.com/releases/2010/06/100602094507.htm>.
The Mount Sinai Hospital / Mount Sinai School of Medicine. (2010, June 2). New cause of cognitive decline in aging population discovered in nerve cell specializations. ScienceDaily. Retrieved December 18, 2014 from www.sciencedaily.com/releases/2010/06/100602094507.htm
The Mount Sinai Hospital / Mount Sinai School of Medicine. "New cause of cognitive decline in aging population discovered in nerve cell specializations." ScienceDaily. www.sciencedaily.com/releases/2010/06/100602094507.htm (accessed December 18, 2014).

Share This


More From ScienceDaily



More Mind & Brain News

Thursday, December 18, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Yoga Could Be As Beneficial For The Heart As Walking, Biking

Yoga Could Be As Beneficial For The Heart As Walking, Biking

Newsy (Dec. 17, 2014) Yoga can help your weight, blood pressure, cholesterol and heart just as much as biking and walking does, a new study suggests. Video provided by Newsy
Powered by NewsLook.com
1st Responders Trained for Autism Sensitivity

1st Responders Trained for Autism Sensitivity

AP (Dec. 16, 2014) More departments are ordering their first responders to sit in on training sessions that focus on how to more effectively interact with those with autism spectrum disorder (Dec. 16) Video provided by AP
Powered by NewsLook.com
Guys Are Idiots, According To Sarcastic Study

Guys Are Idiots, According To Sarcastic Study

Newsy (Dec. 12, 2014) A study out of Britain suggest men are more idiotic than women based on the rate of accidental deaths and other factors. Video provided by Newsy
Powered by NewsLook.com
Believing in Father Christmas Good for Children's Imaginations

Believing in Father Christmas Good for Children's Imaginations

AFP (Dec. 12, 2014) As the countdown to Christmas gets underway, so too does the Father Christmas conspiracy. But psychologists say that telling our children about Santa, flying reindeer and elves is good for their imaginations. Duration: 01:57 Video provided by AFP
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:

Breaking News:

Strange & Offbeat Stories


Health & Medicine

Mind & Brain

Living & Well

In Other News

... from NewsDaily.com

Science News

Health News

Environment News

Technology News



Save/Print:
Share:

Free Subscriptions


Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

Get Social & Mobile


Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

Have Feedback?


Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
Mobile: iPhone Android Web
Follow: Facebook Twitter Google+
Subscribe: RSS Feeds Email Newsletters
Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins