Featured Research

from universities, journals, and other organizations

Memory Experts Show Sleeping Rats May Have Visual Dreams

Date:
December 19, 2006
Source:
Massachusetts Institute of Technology
Summary:
Memories of our life stories may be reinforced while we sleep, MIT researchers report December 17 in the advance online edition of Nature Neuroscience.

Memories of our life stories may be reinforced while we sleep, MIT researchers report Dec. 17 in the advance online edition of Nature Neuroscience.

Matthew A. Wilson, professor of brain and cognitive sciences at MIT's Picower Institute for Learning and Memory, and postdoctoral associate Daoyun Ji looked at what happens in rats' brains when they dream about the mazes they ran while they were awake.

In a landmark 2001 study, Wilson showed that rats formed complex memories for sequences of events experienced while they were awake, and that these memories were replayed while they slept--perhaps reflecting the animal equivalent of dreaming.

Because these replayed memories were detected in the hippocampus, the memory center of the brain, the researchers were not able to determine whether they were accompanied by the type of sensory experience that we associate with dreams--in particular, the presence of visual imagery.

In the latest experiment, by recording brain activity simultaneously in the hippocampus and the visual cortex, Wilson and Ji demonstrated that replayed memories did, in fact, contain the visual images that were present during the running experience.

"This work brings us closer to an understanding of the nature of animal dreams and gives us important clues as to the role of sleep in processing memories of our past experiences," Wilson said.

Reinforcing memories

By recording the spiking patterns of electrodes in individual neurons in the rats' brains, Wilson is able to compare the activity of the neurons when the animal is awake and asleep. It turns out that neurons activated when the animal experiences an event while awake are reactivated during sleep.

In addition, the region of the cortex that processes input from the senses and the hippocampus "talk" to each other during sleep, leading researchers to speculate that this process reinforces and consolidates memories.

But research to date lacked specific evidence that episodic memory--times, places and emotions related to events that make up our life stories--is reinforced in the cortex, the hippocampus or both during sleep.

For the first time, this work shows that the brain is replaying memory events in two locations at once--in the visual cortex and in the hippocampus.

"These results imply simultaneous reactivation of coherent memory traces in the cortex and hippocampus during sleep that may contribute to or reflect the result of the memory consolidation process," Wilson and Ji wrote.

This work is supported by the Brain Science Institute at the Institute of Physical and Chemical Research (RIKEN) in Japan and the National Institutes of Health.


Story Source:

The above story is based on materials provided by Massachusetts Institute of Technology. Note: Materials may be edited for content and length.


Cite This Page:

Massachusetts Institute of Technology. "Memory Experts Show Sleeping Rats May Have Visual Dreams." ScienceDaily. ScienceDaily, 19 December 2006. <www.sciencedaily.com/releases/2006/12/061219094456.htm>.
Massachusetts Institute of Technology. (2006, December 19). Memory Experts Show Sleeping Rats May Have Visual Dreams. ScienceDaily. Retrieved October 20, 2014 from www.sciencedaily.com/releases/2006/12/061219094456.htm
Massachusetts Institute of Technology. "Memory Experts Show Sleeping Rats May Have Visual Dreams." ScienceDaily. www.sciencedaily.com/releases/2006/12/061219094456.htm (accessed October 20, 2014).

Share This



More Mind & Brain News

Monday, October 20, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Your Birth Season Might Determine Your Temperament

Your Birth Season Might Determine Your Temperament

Newsy (Oct. 20, 2014) A new study says the season you're born in can determine your temperament — and one season has a surprising outcome. Video provided by Newsy
Powered by NewsLook.com
Court Ruling Means Kids' Online Activity Could Be On Parents

Court Ruling Means Kids' Online Activity Could Be On Parents

Newsy (Oct. 17, 2014) In a ruling attorneys for both sides agreed was a first of its kind, a Georgia appeals court said parents can be held liable for what kids put online. Video provided by Newsy
Powered by NewsLook.com
The Best Foods To Boost Your Mood

The Best Foods To Boost Your Mood

Buzz60 (Oct. 17, 2014) Feeling down? Reach for the refrigerator, not the medicine cabinet! TC Newman (@PurpleTCNewman) shares some of the best foods to boost your mood. Video provided by Buzz60
Powered by NewsLook.com
You Can Get Addicted To Google Glass, Apparently

You Can Get Addicted To Google Glass, Apparently

Newsy (Oct. 15, 2014) Researchers claim they’ve diagnosed the first example of the disorder in a 31-year-old U.S. Navy serviceman. 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