Featured Research

from universities, journals, and other organizations

New Discoveries About Neuron Plasticity Linked To Learning And Memory

Date:
November 3, 2005
Source:
University of Texas at Austin
Summary:
Neurons experience large-scale changes across their dendrites during learning, say neuroscientists at The University of Texas at Austin in a new study that highlights the important role that these cell regions may play in the processes of learning and memory. The research, published this month in Nature Neuroscience, shows that ion channels distributed in the dendritic membrane change during a simulated learning task and that this requires the rapid production of new proteins.

Neurons experience large-scale changes across their dendrites during learning, say neuroscientists at The University of Texas at Austin in a new study that highlights the important role that these cell regions may play in the processes of learning and memory.

The research, published online Oct. 23 and in the November issue of the journal Nature Neuroscience, shows that ion channels distributed in the dendritic membrane change during a simulated learning task and that this requires the rapid production of new proteins.

"Our new work strongly supports the idea that learning involves changes in dendrites," says Dr. Daniel Johnston, director of the Center for Learning and Memory and professor in the Institute for Neuroscience.

The finding could also lead to advances in understanding conditions like epilepsy and age-related memory loss and could point to potential treatment opportunities for such conditions in the future.

Dendrites--the thin branch-like extensions of a neuron cell--receive many inputs from other neurons that transmit information through contact points called synapses. Much attention has been focused on the role that changes at synapses play in learning. They change in ways that make it easier for connected neurons to pass information.

Johnston and his colleagues show that learning and memory are likely to not only involve changes at synapses, but also in dendrites. They found that h-channels, which are distributed throughout the dendrite membrane and allow the passage of potassium and sodium ions into and out of the neuron, are altered during learning.

"The h-channels undergo plasticity, not near the synapse but probably throughout the dendritic tree," says Johnston.

To record the changes during learning, cells from the rat hippocampus (an important area of the brain for short-term memory) were electrically stimulated using a high frequency pattern called theta-bursts. Theta-bursts mimic the electrical stimulus that shoots through neurons when animals perform a learning task. The researchers found that when stimulated with theta-bursts, hippocampus neurons showed h-channel plasticity and a rapid increase in the synthesis of h-channel proteins.

The proteins were produced in the rat hippocampal neurons within 10 minutes, which is pretty rapid for cells, says Johnston.

"This really pushes the envelope with respect to how fast a neuron can produce new proteins important for learning," he says.

Learning and memory researchers know that protein synthesis in neurons is related to long-term memory, because protein synthesis inhibitors block long-term memory in animals.

Johnston says it's possible that the new proteins are being used by the neuron to build more h-channels in the dendrite membrane. He has a working hypothesis that h-channels may help buffer receiving neurons from being barraged and over-stimulated by inputs coming from information transmitting neurons.

"The h-channel plasticity alters the way the entire dendritic tree responds to the synaptic inputs," he says.

H-channel plasticity may normalize the firing rate of the cell.

"If cells aren't kept in a normal operating regime, learning would not be as effective," Johnston says. "H-channel plasticity might keep the cell within an operating window in which it can continue to learn."



Story Source:

The above story is based on materials provided by University of Texas at Austin. Note: Materials may be edited for content and length.


Cite This Page:

University of Texas at Austin. "New Discoveries About Neuron Plasticity Linked To Learning And Memory." ScienceDaily. ScienceDaily, 3 November 2005. <www.sciencedaily.com/releases/2005/11/051103082711.htm>.
University of Texas at Austin. (2005, November 3). New Discoveries About Neuron Plasticity Linked To Learning And Memory. ScienceDaily. Retrieved July 29, 2014 from www.sciencedaily.com/releases/2005/11/051103082711.htm
University of Texas at Austin. "New Discoveries About Neuron Plasticity Linked To Learning And Memory." ScienceDaily. www.sciencedaily.com/releases/2005/11/051103082711.htm (accessed July 29, 2014).

Share This




More Mind & Brain News

Tuesday, July 29, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Losing Sleep Leaves You Vulnerable To 'False Memories'

Losing Sleep Leaves You Vulnerable To 'False Memories'

Newsy (July 27, 2014) A new study shows sleep deprivation can make it harder for people to remember specific details of an event. Video provided by Newsy
Powered by NewsLook.com
University Quiz Implies Atheists Are Smarter Than Christians

University Quiz Implies Atheists Are Smarter Than Christians

Newsy (July 25, 2014) An online quiz from a required course at Ohio State is making waves for suggesting atheists are inherently smarter than Christians. Video provided by Newsy
Powered by NewsLook.com
Beatings and Addiction: Pakistan Drug 'clinic' Tortures Patients

Beatings and Addiction: Pakistan Drug 'clinic' Tortures Patients

AFP (July 24, 2014) A so-called drugs rehab 'clinic' is closed down in Pakistan after police find scores of ‘patients’ chained up alleging serial abuse. Duration 03:05 Video provided by AFP
Powered by NewsLook.com
New Painkiller Designed To Discourage Abuse: Will It Work?

New Painkiller Designed To Discourage Abuse: Will It Work?

Newsy (July 24, 2014) The FDA approved Targiniq ER on Wednesday, a painkiller designed to keep users from abusing it. Like any new medication, however, it has doubters. 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:
from the past week

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