Featured Research

from universities, journals, and other organizations

Structural brain alterations in patients with irritable bowel syndrome discovered

Date:
July 23, 2010
Source:
University of California - Los Angeles
Summary:
A large academic study has demonstrated structural changes in specific brain regions in female patients with irritable bowel syndrome, a condition that causes pain and discomfort in the abdomen, along with diarrhea, constipation or both. According to researchers, the finding removes the idea once and for all that IBS symptoms are not real and are "only psychological."

This MRI image demonstrates structural brain changes between patients who characterized IBS symptoms primarily as pain, compared with non-painful discomfort.
Credit: UCLA

A large academic study has demonstrated structural changes in specific brain regions in female patients with irritable bowel syndrome (IBS), a condition that causes pain and discomfort in the abdomen, along with diarrhea, constipation or both.

Related Articles


A collaborative effort between UCLA and Canada's McGill University, the study appears in the July issue of the journal Gastroenterology.

The findings show that IBS is associated with both decreases and increases in grey matter density in key areas of the brain involved in attention, emotion regulation, pain inhibition and the processing of visceral information.

IBS affects approximately 15 percent of the U.S. population, primarily women. Currently, the condition is considered by the medical field to be a "functional" syndrome of the digestive tract not working properly rather than an "organic" disorder with structural organ changes. Efforts to identify structural or biochemical alterations in the gut have largely been unsuccessful. Even though the pathophysiology is not completely understood, it is generally agreed that IBS represents an alteration in brain-gut interactions.

These study findings, however, show actual structural changes to the brain, which places IBS in the category of other pain disorders, such as lower back pain, temporomandibular joint disorder, migraines and hip pain -- conditions in which some of the same anatomical brain changes have been observed, as well as other changes. A recent, smaller study suggested structural brain changes in IBS, but a larger definitive study hadn't been completed until now.

"Discovering structural changes in the brain, whether they are primary or secondary to the gastrointestinal symptoms, demonstrates an 'organic' component to IBS and supports the concept of a brain-gut disorder," said study author Dr. Emeran Mayer, professor of medicine, physiology and psychiatry at the David Geffen School of Medicine at UCLA. "Also, the finding removes the idea once and for all that IBS symptoms are not real and are 'only psychological.' The findings will give us more insight into better understanding IBS."

Researchers employed imaging techniques to examine and analyze brain anatomical differences between 55 female IBS patients and 48 female control subjects. Patients had moderate IBS severity, with disease duration from one to 34 years (average 11 years). The average age of the participants was 31.

Investigators found both increases and decreases of brain grey matter in specific cortical brain regions.

Even after accounting for additional factors such as anxiety and depression, researchers still discovered differences between IBS patients and control subjects in areas of the brain involved in cognitive and evaluative functions, including the prefrontal and posterior parietal cortices, and in the posterior insula, which represents the primary viscerosensory cortex receiving sensory information from the gastrointestinal tract.

"The grey-matter changes in the posterior insula are particularly interesting since they may play a role in central pain amplification for IBS patients," said study author David A. Seminowicz, Ph.D., of the Alan Edwards Centre for Research on Pain at McGill University. "This particular finding may point to a specific brain difference or abnormality that plays a role in heightening pain signals that reach the brain from the gut."

Decreases in grey matter in IBS patients occurred in several regions involved in attentional brain processes, which decide what the body should pay attention to. The thalamus and midbrain also showed reductions, including a region -- the periaqueductal grey -- that plays a major role in suppressing pain.

"Reductions of grey matter in these key areas may demonstrate an inability of the brain to effectively inhibit pain responses," Seminowicz said.

The observed decreases in brain grey matter were consistent across IBS patient sub-groups, such as those experiencing more diarrhea-like symptoms than constipation.

"We noticed that the structural brain changes varied between patients who characterized their symptoms primarily as pain, rather than non-painful discomfort," said Mayer, director of the UCLA Center for Neurobiology of Stress. "In contrast, the length of time a patient has had IBS was not related to these structural brain changes."

Mayer added that the next steps in the research will include exploring whether genes can be identified that are related to these structural brain changes. In addition, there is a need to increase the study sample size to address male-female differences and to determine if these brain changes are a cause or consequence of having IBS.

The study was funded by the National Institutes of Health.

Additional authors include M. Catherine Bushnell, Ph.D., of McGill University, and Jennifer B. Labus, Joshua A. Bueller, Kirsten Tillisch and Bruce D. Naliboff, Ph.D., all of UCLA.


Story Source:

The above story is based on materials provided by University of California - Los Angeles. Note: Materials may be edited for content and length.


Cite This Page:

University of California - Los Angeles. "Structural brain alterations in patients with irritable bowel syndrome discovered." ScienceDaily. ScienceDaily, 23 July 2010. <www.sciencedaily.com/releases/2010/07/100722132433.htm>.
University of California - Los Angeles. (2010, July 23). Structural brain alterations in patients with irritable bowel syndrome discovered. ScienceDaily. Retrieved November 23, 2014 from www.sciencedaily.com/releases/2010/07/100722132433.htm
University of California - Los Angeles. "Structural brain alterations in patients with irritable bowel syndrome discovered." ScienceDaily. www.sciencedaily.com/releases/2010/07/100722132433.htm (accessed November 23, 2014).

Share This


More From ScienceDaily



More Health & Medicine News

Sunday, November 23, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Ebola-Hit Sierra Leone's Late Cocoa Leaves Bitter Taste

Ebola-Hit Sierra Leone's Late Cocoa Leaves Bitter Taste

AFP (Nov. 23, 2014) The arable district of Kenema in Sierra Leone -- at the centre of the Ebola outbreak in May -- has been under quarantine for three months as the cocoa harvest comes in. Duration: 01:32 Video provided by AFP
Powered by NewsLook.com
Don't Fall For Flu Shot Myths

Don't Fall For Flu Shot Myths

Newsy (Nov. 23, 2014) Misconceptions abound when it comes to your annual flu shot. Medical experts say most people older than 6 months should get the shot. Video provided by Newsy
Powered by NewsLook.com
WFP: Ebola Risks Heightened Among Women Throughout Africa

WFP: Ebola Risks Heightened Among Women Throughout Africa

AFP (Nov. 21, 2014) Having children has always been a frightening prospect in Sierra Leone, the world's most dangerous place to give birth, but Ebola has presented an alarming new threat for expectant mothers. Duration: 00:37 Video provided by AFP
Powered by NewsLook.com
Could Your Genes Be The Reason You're Single?

Could Your Genes Be The Reason You're Single?

Newsy (Nov. 21, 2014) Researchers in Beijing discovered a gene called 5-HTA1, and carriers are reportedly 20 percent more likely to be single. 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