Understanding how brain structure and function are altered in eating disorders, such as anorexia nervosa and bulimia nervosa, is essential for advancing and improving treatment strategies.

A recent study offers the first comparative analysis using advanced MR imaging to compare brain structure and function in women with these eating disorders to healthy controls. The study revealed neurobiological differences, exploring how these illnesses impact the brain and behavior.

The study
This research, centered on female participants, compared 57 healthy individuals with 130 participants diagnosed with eating disorders, anorexia nervosa, and bulimia nervosa subtypes. Structural and functional MRI scans were used to investigate different parameters of brain anatomy, such as gray matter volume and cortical thickness.

During functional MRI, activity patterns linked to reward response, emotional regulation, and self-control were obtained. Whole-brain analyses were performed to explore how these differences relate to the psychological characteristics of the eating disorders.

The study found that women with eating disorders showed structural brain changes even after accounting for differences in body weight. Key areas affected included the orbitofrontal cortex and the middle frontal gyrus. These changes were linked to behaviors central to eating disorders, such as impulsivity and rigid control over eating.

For example, a reduction in gray matter volume in the orbitofrontal cortex was tied to impulsive behavior, while thinning of the middle frontal gyrus was associated with cognitive restraint, a hallmark of anorexia. These structural changes were particularly pronounced in women with anorexia.

Women with eating disorders had distinct patterns of brain activity on the functional scan during tasks involving rewards, emotions, and self-control. For instance, during reward anticipation, areas like the cerebellum and the superior frontal gyrus were less active, while the lingual gyrus showed reduced responses. These functional changes were connected to heightened emotional sensitivity, a personality trait often linked to eating disorders.

A destructive brain-mind cycle
The study suggested that these brain changes, partly driven by malnutrition, disrupt how rewards are processed and emotions are managed.

This creates a vicious cycle where the brain changes to reinforce the behaviors and thoughts that sustain the eating disorder. By identifying specific brain regions and their roles in the disorders, the research points to potential new strategies for treatment, targeting these areas to break the cycle and improve outcomes.

About the scientific paper:

First author: Xinyang Yu , UK
Published in: Biological Psychiatry. November 2024.
Link to paper: https://www.biologicalpsychiatryjournal.com/article/S0006-3223(24)01759-1/fulltext