Featured Research

from universities, journals, and other organizations

Getting a grip on sleep

Date:
May 14, 2013
Source:
RIKEN
Summary:
All mammals sleep, as do birds and some insects. However, how this basic function is regulated by the brain remains unclear. According to a new study, a brain region called the lateral habenula plays a central role in the regulation of REM sleep.

Schematic drawing of the habenular neural circuit.
Credit: Image courtesy of RIKEN

All mammals sleep, as do birds and some insects. However, how this basic function is regulated by the brain remains unclear. According to a new study by researchers from the RIKEN Brain Science Institute, a brain region called the lateral habenula plays a central role in the regulation of REM sleep. In an article published today in the Journal of Neuroscience, the team shows that the lateral habenula maintains and regulates REM sleep in rats through regulation of the serotonin system.

This study is the first to show a role of the lateral habenula in linking serotonin metabolism and sleep.

The lateral habenula is a region of the brain known to regulate the metabolism of the neurotransmitter serotonin in the brain and to play a key role in cognitive functions.

“Serotonin plays a central role in the pathophysiology of depression, however, it is not clear how abnormalities in regulation of serotonin metabolism in the brain lead to symptoms such as insomnia in depression,” explain Dr. Hidenori Aizawa and Dr. Hitoshi Okamoto who led the study.

Since animals with increased serotonergic activity at the synapse experienced less REM sleep, the researchers hypothesized that the lateral habenula, which regulates serotonergic activity in the brain, must modulate the duration of REM sleep.

They show that removing the lateral habenula in rats results in a reduction of theta rhythm, an oscillatory activity that appears during REM sleep, in the hippocampus, and shortens the rats’ REM sleep periods. However, this inhibitory effect of the lateral habenular lesion on REM sleep disappears when the serotonergic neurons in the midbrain are lesioned.

The team recorded neural activity simultaneously in the lateral habenula and hippocampus in a sleeping rat. They find that the lateral habenular neurons, which fire persistently during non-REM sleep, begin to fire rhythmically in accordance with the theta rhythm in the hippocampus when the animal is in REM sleep.

“Our results indicate that the lateral habenula is essential for maintaining theta rhythms in the hippocampus, which characterize REM sleep in the rat, and that this is done via serotonergic modulation,” concludes Dr Aizawa.

“This study reveals a novel role of the lateral habenula, linking serotonin and REM sleep, which suggests that an hyperactive habenula in patients with depression may cause altered REM sleep,” add the authors.


Story Source:

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


Journal Reference:

  1. Aizawa et al. The Synchronous Activity of Lateral Habenular Neurons Is Essential for Regulating Hippocampal Theta Oscillation. The Journal of Neuroscience, 2013 DOI: 10.1523/JNEUROSCI.4369-12.2013

Cite This Page:

RIKEN. "Getting a grip on sleep." ScienceDaily. ScienceDaily, 14 May 2013. <www.sciencedaily.com/releases/2013/05/130514184514.htm>.
RIKEN. (2013, May 14). Getting a grip on sleep. ScienceDaily. Retrieved August 28, 2014 from www.sciencedaily.com/releases/2013/05/130514184514.htm
RIKEN. "Getting a grip on sleep." ScienceDaily. www.sciencedaily.com/releases/2013/05/130514184514.htm (accessed August 28, 2014).

Share This




More Mind & Brain News

Thursday, August 28, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Alice in Wonderland Syndrome

Alice in Wonderland Syndrome

Ivanhoe (Aug. 27, 2014) It’s an unusual condition with a colorful name. Kids with “Alice in Wonderland” syndrome see sudden distortions in objects they’re looking at or their own bodies appear to change size, a lot like the main character in the Lewis Carroll story. Video provided by Ivanhoe
Powered by NewsLook.com
Stopping Schizophrenia Before Birth

Stopping Schizophrenia Before Birth

Ivanhoe (Aug. 27, 2014) Scientists have long called choline a “brain booster” essential for human development. Not only does it aid in memory and learning, researchers now believe choline could help prevent mental illness. Video provided by Ivanhoe
Powered by NewsLook.com
Personalized Brain Vaccine for Glioblastoma

Personalized Brain Vaccine for Glioblastoma

Ivanhoe (Aug. 27, 2014) Glioblastoma is the most common and aggressive brain cancer in humans. Now a new treatment using the patient’s own tumor could help slow down its progression and help patients live longer. Video provided by Ivanhoe
Powered by NewsLook.com
Brain Surgery in 3-D

Brain Surgery in 3-D

Ivanhoe (Aug. 27, 2014) Neurosurgeons now have a new approach to brain surgery using the same 3D glasses you’d put on at an IMAX movie theater. Video provided by Ivanhoe
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