Altered cortical folding and reduced sulcal depth in adults with anorexia nervosa

Previous studies on anorexia nervosa (AN) focused on cortical volume and mainly reported grey matter reduction. They also investigated cortical surface parameters, for example, absolute mean curvature (AMC) providing information on cortical folding or sulcal depth (SD). For the first time, we also analysed cortical complexity using fractal dimension (FD) in AN.

In a cross-sectional study, we performed surface analyses (AMC, SD, and FD) on 34 women with AN, 24 recovered from AN (REC), and 41 healthy controls (HC). Structural MR data was processed using the Computational Anatomy Toolbox and statistically compared across groups on a vertex- and region-of-interest-wise level using statistical parametric mapping.

We found a lower AMC and SD in AN, especially in temporal areas. FD was increased in the left precentral gyrus in AN. No differences of the parameters AMC, SD, or FD were evident between REC and HC participants.

Alterations in AMC, SD, and FD in AN patients, but not between the REC and HC groups, suggest that these alterations are state related. The findings concur with other structural AN studies that suggest restitution with clinical recovery. The changes may be due to malnutrition, dehydration, osmotic dysregulation, or hormonal aberrations during the acute stage.