Find Information About:

Drugs & Supplements

Get information and reviews on prescription drugs, over-the-counter medications, vitamins, and supplements. Search by name or medical condition.

Pill Identifier

Pill Identifier

Having trouble identifying your pills?

Enter the shape, color, or imprint of your prescription or OTC drug. Our pill identification tool will display pictures that you can compare to your pill.

Get Started
My Medicine

My Medicine

Save your medicine, check interactions, sign up for FDA alerts, create family profiles and more.

Get Started

WebMD Health Experts and Community

Talk to health experts and other people like you in WebMD's Communities. It's a safe forum where you can create or participate in support groups and discussions about health topics that interest you.

  • Second Opinion

    Second Opinion

    Read expert perspectives on popular health topics.

  • Community


    Connect with people like you, and get expert guidance on living a healthy life.

Got a health question? Get answers provided by leading organizations, doctors, and experts.

Get Answers

Sign up to receive WebMD's award-winning content delivered to your inbox.

Sign Up

Brain & Nervous System Health Center

Font Size

Stomach Full? Brain May Not Know

Overweight People's Brains Seem Slow to Sense Satiety
WebMD Health News
Reviewed by Louise Chang, MD

Jan. 11, 2008 -- Overweight people's brains may not know when their stomachs are full, a brain scan study suggests.

The findings come from Gene-Jack Wang, MD, of Brookhaven National Laboratory, Nora D. Volkow, MD, director of the National Institute on Drug Abuse, and colleagues. These researchers have used real-time brain scans to explore addictive behaviors. They're also looking at interactions between eating behaviors and brain function.

In their new study, Wang and colleagues had 18 adult volunteers swallow balloons -- sections of latex condoms tied off with unwaxed dental floss -- attached to a long tube. Once the balloons were in the patients' stomachs, the researchers filled them with body-temperature water. The idea was to simulate eating enough food to fill the stomach.

While the balloons were being filled, the researchers scanned the patients' brains. At various times during the experiment -- when the balloons were partially or fully filled -- the patients were asked how full they felt, how uncomfortable they were, how hungry they were, and how much they wanted food. The patients had not eaten since 7 p.m. the night before the experiments, which were conducted between 11 a.m. and 1 p.m.

Perhaps not surprisingly -- as they had a tube going down their throat -- the patients reported only a little less hunger and a little more desire for food when the balloons were full.

Interestingly, the thinner the subject, the more likely that person was to report feeling full when the balloon was full. The heavier the patients, the less likely they were to feel full with a filled water balloon in their stomachs.

Filling the balloon triggered a response in the amygdala, the part of the brain that controls emotional responses -- and possibly feeding behavior. Removal of a specific part of the amygdala causes animals to eat uncontrollably.

Interestingly, the left rear amygdala became active when patients reported feeling full.

"This study provides the first evidence of the connection of the left amygdala and feelings of hunger during stomach fullness, demonstrating that activation of this brain region suppresses hunger," Wang says in a news release.

Wang went on to suggest that possible treatment options for obesity might include brain surgery.

"Our findings indicate a potential direction for treatment strategies -- be they behavioral, medical, or surgical," he says.

Wang and colleagues report their findings in the Feb. 15 issue of the journal NeuroImage.

Today on WebMD

nerve damage
Learn how this disease affects the nervous system.
senior woman with lost expression
Know the early warning signs.
woman in art gallery
Tips to stay smart, sharp, and focused.
medical marijuana plant
What is it used for?
senior man
boy hits soccer ball with head
red and white swirl
marijuana plant
brain illustration stroke
nerve damage
Alzheimers Overview
Graphic of number filled head and dna double helix