Although anorexia nervosa is categorized as an eating disorder, it is not known whether there are alterations of the portions of the brain that regulate appetite.
Now, a new study finds that women with anorexia have distinct differences in the insulta – the specific part of the brain that is important for recognizing taste – according to a new study by University of Pittsburgh and University of California, San Diego researchers.
The study also implies that there may be differences in the processing of information related to self-awareness in recovering anorexics compared to those without the illness – findings that may lead to a better understanding of the cause of this serious and sometimes fatal mental disorder.
In the study led by Angela Wagner, M.D., University of Pittsburgh School of Medicine, and Walter H. Kaye, M.D., of the University of Pittsburgh and the University of California, San Diego (UCSD) Schools of Medicine, the brain activity of 32 women was measured using functional magnetic resonance imaging (fMRI.) The research team looked at images of the brains of 16 women who had recovered from anorexia nervosa – some of whom had been treated at the Center for Overcoming Problem Eating at Western Psychiatric Institute and Clinic of the University of Pittsburgh Medical Center –and 16 control subjects. They measured their brains’ reactions to pleasant taste (sucrose) and neutral taste (distilled water.)
The results of the fMRI study are the first evidence that individuals with anorexia process taste in a different way than those without the eating disorder.
In response to both the sucrose and water, imaging results showed that women who had recovered from anorexia had significantly reduced response in the insula and related brain regions when compared to the control group. These areas of the brain recognize taste and judge how rewarding that taste is to the person. In addition, while the controls showed a strong relationship between how they judged the pleasantness of the taste and the activity of the insula, this relationship was not seen in those who had recovered from anorexia.
According to Kaye, it is possible that individuals with anorexia have difficulty recognizing taste, or responding to the pleasure associated with food. Because this region of the brain also contributes to emotional regulation, it may be that food is aversive, rather than rewarding. This could shed light on why individuals with anorexia avoid normally “pleasurable” foods, fail to appropriately respond to hunger and are able to lose so much weight.
“We know that the insula and the connected regions are thought to play an important role in interoceptive information, which determines how the individual senses the physiological condition of the entire body,” said Kaye. “Interoception has long been thought to be critical for self-awareness because it provides the link between thinking and mood, and the current body state.”
This lack of interoceptive awareness may contribute to other symptoms of anorexia nervosa such as distorted body image, lack of recognition of the symptoms of malnutrition and diminished motivation to change, according to Kaye.
Anorexia nervosa is a serious and potentially lethal illness, which may result in death in ten percent of cases. It is characterized by the relentless pursuit of thinness, emaciation and the obsessive fear of gaining weight. Anorexia commonly begins during adolescence, but strikes throughout the lifespan, and is nine times more common in females than in males. These characteristics support the possibility that biological processes contribute to developing this disorder.
Full article: Neuropsychopharmacology
- PHYSICAL SCIENCES
- EARTH SCIENCES
- LIFE SCIENCES
- SOCIAL SCIENCES
Subscribe to the newsletter
Stay in touch with the scientific world!
Know Science And Want To Write?
- Greenpeace Says Its GMOs Are Better Than Science's GMOs, Still Hates Golden Rice
- Reduce Prostate Cancer Risk By Sleeping With Lots Of Women - But Not Men
- Supersonic Laser-Propelled Aircraft Get A Step Closer
- Homo Floresiensis: Hobbit Species Continues To Provoke Questions About Human Evolution
- Okay With Disgusting Images? You Vote This Way 95 Percent Of The Time
- Everyone Hates Daylight Savings Time - But It Might Improve Public Health
- This Mid-Term Election Can Have Evolutionary Consequences
- "The problem is, American agricultural science cannot be adopted world-wide for the simple reason..."
- "You're quote mining. When it comes to environmental risk, energy emissions from CO2 are back at..."
- "Of course they aren't. These are scientific terms Hank Campbell and you can't just interpret them..."
- "The wealthiest are only formally most educated and, from both my personal expriences and reading..."
- "You think the marker assisted selection suddenly being endorsed by Greenpeace is not genetic modification..."
- Genetically modified clean energy from bacteria
- Designer babies: You can screen for cystic fibrosis but intelligence is a way off
- Science as profane: What superstition of 1752 and 2014 share in common
- What’s so “natural” about “natural crop breeding”?
- Worried you have cancer? Take a Google pill!
- Mars bars for brain health? Not so fast