White Matter Tracts Show Subtle Changes in the Months After Anorexia Hospitalization

A small longitudinal brain-imaging study has tracked how the brain's white matter evolves in young women with anorexia nervosa, from hospital admission through six months after discharge. Using an advanced diffusion MRI technique called fixel-based analysis, the researchers detected a significant increase in a combined measure of fiber density and cross-section in the right cingulum. The findings, published in BMC Psychiatry, indicate that fiber-specific white matter metrics change measurably during the months surrounding hospitalization for anorexia nervosa.

Across the follow-up interval, the combined fiber density and cross-section measure rose significantly in the right cingulum, with a corrected statistical significance threshold of q = 0.017 and an effect estimate of 0.367. The analysis also uncovered two time-by-age interactions. In the posterior midbody of the corpus callosum, the fiber bridge connecting the brain's two hemispheres, older participants showed greater increases in fiber bundle cross-section over time, with q = 0.008 and an effect estimate of 0.118.

A parallel interaction appeared in the left uncinate fasciculus, with q = 0.008 and an effect estimate of 0.195. These interaction effects suggest that age may moderate how white matter metrics evolve during the observed period. Clinically, the participants gained weight as expected during treatment: body mass index increased significantly between the two scans.

Cognitive flexibility also improved significantly over the follow-up interval. In contrast, the eating disorder symptom measures did not change significantly between admission and the six-month post-discharge assessment. The researchers emphasize that the study is exploratory and that its conclusions must be read cautiously.

Because the design lacked a longitudinal healthy control group, the observed white matter changes cannot be attributed specifically to recovery from anorexia, nutritional restoration, treatment effects, or ordinary brain maturation in this age range. Any of these factors, alone or in combination, could account for the tract changes, and the small sample of seventeen participants limits generalizability. The authors frame their results as hypothesis-generating evidence that fiber-specific white matter metrics change measurably during the months surrounding hospitalization for anorexia nervosa.

They conclude that future studies should include longitudinal healthy controls to disentangle recovery-related, nutritional, treatment-related, and developmental contributions to the observed signal changes. Until such controlled designs are available, the right cingulum finding and the age-moderated cross-section changes in the corpus callosum and left uncinate fasciculus stand as measured observations from an exploratory scan-rescan cohort rather than as established markers of recovery from anorexia nervosa.

Subject of Research: Longitudinal fixel-based diffusion MRI study of white matter changes in anorexia nervosa during hospitalization and six-month follow-up

Article Title: Longitudinal white matter changes in anorexia nervosa: an exploratory fixel-based study

Article References: Zemánková, P. H., Musálková, J., Bartoňová, M., Knejzlíková, T., Jáni, M., Rektorová, K., & Kašpárek, T. (2026). Longitudinal white matter changes in anorexia nervosa: an exploratory fixel-based study. BMC Psychiatry. https://doi.org/10.1186/s12888-026-08795-3

Image Credits: AI Generated

DOI: 10.1186/s12888-026-08795-3

Keywords: anorexia nervosa, white matter, fixel-based analysis, diffusion MRI, cingulum, corpus callosum, uncinate fasciculus, fiber density and cross-section, cognitive flexibility, longitudinal study, eating disorders, Longitudinal