Featured Research

from universities, journals, and other organizations

New Understanding Of Basic Units Of Memory

Date:
September 24, 2007
Source:
Duke University Medical Center
Summary:
A molecular "recycling plant" permits nerve cells in the brain to carry out two seemingly contradictory functions -- changeable enough to record new experiences, yet permanent enough to maintain these memories over time.

Michael D. Ehlers, M.D., Ph.D., Assistant Professor, department of neurobiology, Duke University Medical Center
Credit: Image courtesy of Duke University Medical Center

A molecular "recycling plant" permits nerve cells in the brain to carry out two seemingly contradictory functions -- changeable enough to record new experiences, yet permanent enough to maintain these memories over time.

Related Articles


The discovery of this molecular recycling plant, detailed in a study appearing early online Sept. 19 in the journal Neuron, provides new insights into how the basic units of learning and memory function. Individual memories are "burned onto" hundreds of receptors that are constantly in motion around nerve synapses -- gaps between individual nerve cells crucial for signals to travel throughout the brain.

According to the study's leader, Duke University Medical Center neurobiologist Michael Ehlers, M.D., Ph.D., these receptors are constantly moving around the synapse and often times they disappear or escape. Ehlers discovered that a specific set of molecules catch these elusive receptors, take them to the recycling plant where they are reprocessed and returned to the synapse intact.

"These receptors constantly escape the synapse and are in a perpetual state of recycling," said Ehlers, who is also a Howard Hughes Medical Institute investigator. "This process occurs on a time scale of minutes or hours, so the acquisition of new neurotransmitter receptors and their recycling is an on-going process. Memory loss may result from receptors escaping from the synapse."

All this activity takes place on millions of tiny "nubs," or protrusions in the synapses known as dendritic spines. The recycling plants are located within the body of these dendritic spines.

"We believe that the existence of this recycling ability explains in part how individual dendritic spines retain their unique identity amidst this constant molecular turnover," Ehlers said. "The system is simultaneously dynamic and stable."

While these findings should be able to help neurobiologists as they attempt to understand the molecular foundations of learning and memory, Ehlers believes that this knowledge could also be helpful in explaining what happens in certain neurological disorders, such as Alzheimer's disease, schizophrenia, or learning disorders like autism.

For example, it appears that in animal models of the early phases of Alzheimer's disease, often before any symptoms become apparent, the dendritic spines gradually lose their ability to transport and recycle the receptors.

"If the receptors don't get recycled, you see a gradual loss of synaptic function that is associated with reduced cognitive ability," Ehlers said. "These dendritic spines are where learning and memories reside. These are the basic units of memory."

Other Duke members of the team were Jiuyi Lu, Thomas Helton, Thomas Blanpied, Bence Racz and Thomas Newpher. Richard Weinberg of the University of North Carolina -- Chapel Hill was also a member of the team. The research was supported by the National Institutes of Health.


Story Source:

The above story is based on materials provided by Duke University Medical Center. Note: Materials may be edited for content and length.


Cite This Page:

Duke University Medical Center. "New Understanding Of Basic Units Of Memory." ScienceDaily. ScienceDaily, 24 September 2007. <www.sciencedaily.com/releases/2007/09/070919123138.htm>.
Duke University Medical Center. (2007, September 24). New Understanding Of Basic Units Of Memory. ScienceDaily. Retrieved March 1, 2015 from www.sciencedaily.com/releases/2007/09/070919123138.htm
Duke University Medical Center. "New Understanding Of Basic Units Of Memory." ScienceDaily. www.sciencedaily.com/releases/2007/09/070919123138.htm (accessed March 1, 2015).

Share This


More From ScienceDaily



More Mind & Brain News

Sunday, March 1, 2015

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

The Best Foods to Battle Stress

The Best Foods to Battle Stress

Buzz60 (Feb. 26, 2015) If you&apos;re dealing with anxiety, there are a few foods that can help. Krystin Goodwin (@krystingoodwin) has the best foods to tame stress. Video provided by Buzz60
Powered by NewsLook.com
Sleeping Too Much Or Too Little Might Increase Stroke Risk

Sleeping Too Much Or Too Little Might Increase Stroke Risk

Newsy (Feb. 26, 2015) People who sleep more than eight hours per night are 45 percent more likely to have a stroke, according to a University of Cambridge study. Video provided by Newsy
Powered by NewsLook.com
Mayor Says District of Columbia to Go Ahead With Pot Legalization

Mayor Says District of Columbia to Go Ahead With Pot Legalization

Reuters - News Video Online (Feb. 25, 2015) Washington&apos;s mayor says the District of Columbia will move forward with marijuana legalization, despite pushback from Congress. Rough Cut (no reporter narration). Video provided by Reuters
Powered by NewsLook.com
Marijuana Nowhere Near As Deadly As Alcohol: Study

Marijuana Nowhere Near As Deadly As Alcohol: Study

Newsy (Feb. 25, 2015) A new study says marijuana is about 114 times less deadly than alcohol. Video provided by Newsy
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