A team of neuroscientists at the University of Bath (UK) with international partners has revealed the essential differences in brain structure between people with and without anorexia nervosa. A severe eating disorder and mental health condition, Anorexia, affects over a quarter of a million people aged 16 and over in the UK. According to the experts, symptoms are characterised by people trying to keep their weight as low as possible by not eating enough.
It is still unknown why some people develop anorexia whilst others do not. However, biological factors are widely recognised. The findings of the study were published in the journal Biological Psychiatry.
In the study, the scientists have revealed that people with anorexia demonstrate ‘sizeable reductions’ in three critical measures of the brain: cortical thickness, subcortical volumes, and cortical surface area. Moreover, reductions in brain size are significant because they are thought to imply the loss of brain cells or the connections between them.
According to the scientists, the outcomes of the study are some of the clearest yet to show links between structural changes in the brain and eating disorders. The researchers reveal that the effect sizes in their study for anorexia are in fact the largest of any psychiatric disorder investigated to date. This suggests that people with anorexia showed reductions in brain size and shape between two and four times larger than people with conditions such as depression, ADHD, or OCD. The changes observed in brain size for anorexia might be attributed to reductions in people’s body mass index (BMI), according to scientists.
While conducting the study, the scientists pooled nearly 2,000 pre-existing brain scans for people with anorexia, including people in recovery and ‘healthy controls’. For people in recovery from anorexia, the study found that reductions in brain structure were less severe. This could mean that with appropriate early treatment and support, the brain might be able to repair itself.
“For this study, we worked intensively over several years with research teams across the world. Being able to combine thousands of brain scans from people with anorexia allowed us to study the brain changes that might characterise this disorder in much greater detail. We found that the large reductions in brain structure, which we observed in patients, were less noticeable in patients already on the path to recovery. This is a good sign, because it indicates that these changes might not be permanent. With the right treatment, the brain might be able to bounce back,” Lead researcher, Dr Esther Walton of the Department of Psychology at the University of Bath said.
The research team also involved academics working at The Technical University in Dresden, Germany; the Icahn School of Medicine at Mount Sinai, New York; and King’s College London.
To understand the link between brain structure, function and mental health, the team worked together as part of the ENIGMA Eating Disorders Working Group, run by the University of Southern California. The ENIGMA Consortium is an international effort to bring together researchers in imaging genomics, neurology and psychiatry.
The team of scientists also maintained that this study is novel in terms of the thousands of brain scans analysed. According to the researchers, this reveals that anorexia affects the brain more “profoundly” than any other psychiatric condition.
