The Relationship Between Precuneus Thickness and Psychopathology in Adolescent Females With Anorexia Nervosa

Anorexia nervosa (AN) is a severe psychiatric disorder with structural brain alterations; however, the roles of cortical surface area (CSA) and cortical thickness (CTh) during adolescence remain unclear. Building on frequent reports of gray matter reductions in the cingulate cortex and precuneus, this study assesses CSA, CTh, and cortical volume in these regions, alongside exploratory whole-brain analyses and their associations with psychological dimensions.

We included 26 adolescent females aged 12-19 years with acute AN and 24 age-matched healthy controls. Participants underwent high-resolution structural MRI and completed psychological assessments: Eating Disorder Inventory-2 (EDI-II), Beck Anxiety Inventory (BAI), Beck Depression Inventory-II (BDI-II), Perth Alexithymia Questionnaire (PAQ), and Body Perception Questionnaire. MRI data were processed using BIDScoin, fMRIPrep, and FreeSurfer. Analyses included permutation-based non-parametric testing and multiple regression to investigate associations between brain metrics and psychological scores.

In primary analyses, individuals with AN exhibited a significant reduction in precuneus CTh only. Precuneus CTh correlated negatively with EDI-II, BAI, and BDI-II scores, and positively with BMI-SDS. Regression analysis identified anxiety (BAI), specific EDI-II subscales, supra-diaphragmatic autonomic reactivity and difficulties describing negative feelings (PAQ) as predictors of precuneus CTh. Exploratory analyses revealed thickness differences in parietal and frontal regions, consistent with prior large-scale studies, with anxiety and depression scores correlating with several of these regions.

Reduced precuneus CTh and its association with psychological factors highlight its role in AN's neurobiological mechanisms. Exploratory findings implicate parietal and frontal alterations, suggesting broader disruptions in body perception and behavioral control.