'Connection error' in the brains of anorexics

January 24, 2013

RUB researchers find altered connectivity in the brain network for body perception. The weaker the connection, the greater the misjudgement of body shape

When people see pictures of bodies, a whole range of brain regions are active. This network is altered in women with anorexia nervosa. In a functional magnetic resonance imaging study, two regions that are important for the processing of body images were functionally more weakly connected in anorexic women than in healthy women. The stronger this "connection error" was, the more overweight the respondents considered themselves. "These alterations in the brain could explain why women with anorexia perceive themselves as fatter, even though they are objectively underweight" says Prof. Dr. Boris Suchan of the Institute of Cognitive Neuroscience at the Ruhr-Universität. Together with Prof. Dr. Dietrich Grönemeyer (University of Witten-Herdecke), Prof. Dr. Silja Vocks (University of Osnabrück) and other colleagues, the Bochum researchers report in the journal Behavioural Brain Research.

Anorexics misperceive their body shape

The researchers tested ten anorexic and fifteen healthy women of similar age. To start with, all the women judged on the computer which of several different silhouettes corresponded best to their own body shape. Ten control subjects who did not participate in the MRI scan answered the same question by matching a photo of the test subject to the right silhouette. Both healthy and anorexic women estimated their body shape differently than outsiders: healthy subjects rated themselves as thinner than the control subjects. Anorexic women on the other hand perceived themselves to be fatter than the control subjects did.

Brain areas for body perception examined with MRI

In MRI scanners, the researchers then recorded the brain activity of the 25 participants while they observed photos of bodies. Above all, they analysed the activity in the "fusiform body area" (FBA) and the "extrastriate body area" (EBA), because previous studies showed that these brain regions are critical for the perception of bodies. To this end, the neuroscientists from Bochum calculated the so-called effective connectivity between the FBA and EBA in both hemispheres. This is a measure of how much the activity in several brain areas is temporally correlated. A high degree of correlation is indicative of a strong connection.

Brains of anorexics structurally and functionally altered

The connection between the FBA and EBA was weaker in women with anorexia nervosa than in healthy women. In addition, the researchers found a negative correlation between the EBA-FBA connection in the left hemisphere and the misjudgement of body weight: the weaker the effective connectivity between the EBA and FBA was, the fatter the subjects with anorexia falsely estimated themselves to be. "In a previous study we found that there are structural changes in the brains of patients with anorexia", says Boris Suchan. They have a lower density of nerve cells in the EBA. "The new data shows that the network for body processing is also functionally altered." The EBA, which has a lower cell density in anorexics, is also the area that stood out in the connection analysis: it receives reduced input from the FBA. "These changes could provide a mechanism for the development of anorexia", says Suchan.
-end-
Bibliographic record

B. Suchan, D. Soria Bauser, M. Busch, D. Schulte, D. Grönemeyer, S. Herpertz, S. Vocks (2012): Reduced connectivity between the left fusiform body area and the extrastriate body area in anorexia nervosa is associated with body image distortion, Behavioural Brain Research, DOI: 10.1016/j.bbr.2012.12.002

Figure online

A figure related to this press release can be found online at: http://aktuell.ruhr-uni-bochum.de/pm2013/pm00019.html.en

Further information

Prof. Dr. Boris Suchan, Department of Neuropsychology, Institute of Cognitive Neuroscience at the Ruhr-Universität, 44780 Bochum, Germany, Tel. +49/234/32-27575 boris.suchan@rub.de

Click for more

Previous press release on brain changes in anorexia (German) http://aktuell.ruhr-uni-bochum.de/pm2010/msg00005.htm

Editor: Dr. Julia Weiler

Ruhr-University Bochum

Related Brain Articles from Brightsurf:

Glioblastoma nanomedicine crosses into brain in mice, eradicates recurring brain cancer
A new synthetic protein nanoparticle capable of slipping past the nearly impermeable blood-brain barrier in mice could deliver cancer-killing drugs directly to malignant brain tumors, new research from the University of Michigan shows.

Children with asymptomatic brain bleeds as newborns show normal brain development at age 2
A study by UNC researchers finds that neurodevelopmental scores and gray matter volumes at age two years did not differ between children who had MRI-confirmed asymptomatic subdural hemorrhages when they were neonates, compared to children with no history of subdural hemorrhage.

New model of human brain 'conversations' could inform research on brain disease, cognition
A team of Indiana University neuroscientists has built a new model of human brain networks that sheds light on how the brain functions.

Human brain size gene triggers bigger brain in monkeys
Dresden and Japanese researchers show that a human-specific gene causes a larger neocortex in the common marmoset, a non-human primate.

Unique insight into development of the human brain: Model of the early embryonic brain
Stem cell researchers from the University of Copenhagen have designed a model of an early embryonic brain.

An optical brain-to-brain interface supports information exchange for locomotion control
Chinese researchers established an optical BtBI that supports rapid information transmission for precise locomotion control, thus providing a proof-of-principle demonstration of fast BtBI for real-time behavioral control.

Transplanting human nerve cells into a mouse brain reveals how they wire into brain circuits
A team of researchers led by Pierre Vanderhaeghen and Vincent Bonin (VIB-KU Leuven, Université libre de Bruxelles and NERF) showed how human nerve cells can develop at their own pace, and form highly precise connections with the surrounding mouse brain cells.

Brain scans reveal how the human brain compensates when one hemisphere is removed
Researchers studying six adults who had one of their brain hemispheres removed during childhood to reduce epileptic seizures found that the remaining half of the brain formed unusually strong connections between different functional brain networks, which potentially help the body to function as if the brain were intact.

Alcohol byproduct contributes to brain chemistry changes in specific brain regions
Study of mouse models provides clear implications for new targets to treat alcohol use disorder and fetal alcohol syndrome.

Scientists predict the areas of the brain to stimulate transitions between different brain states
Using a computer model of the brain, Gustavo Deco, director of the Center for Brain and Cognition, and Josephine Cruzat, a member of his team, together with a group of international collaborators, have developed an innovative method published in Proceedings of the National Academy of Sciences on Sept.

Read More: Brain News and Brain Current Events
Brightsurf.com is a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for sites to earn advertising fees by advertising and linking to Amazon.com.