1 THE CEREBELLUM PLAYS MORE THAN ONE ROLE IN APPETITE CONTROL: EVIDENCE FROM TYPICAL AND PATHOLOGICAL POPULATIONS Authors: Michelle Sader 1 *, Gordon D. Waiter 2 , Justin H. G. Williams 1 1 Translational Neuroscience, Institute of Medical Sciences, University of Aberdeen, Aberdeen, United Kingdom 2 Aberdeen Biomedical Imaging Centre, Lilian Sutton Building, Institute of Medical Sciences, University of Aberdeen, United Kingdom *Correspondence: Michelle Sader – m.sader.19@abdn.ac.uk; (+44) 01224 438365 ___________________________________________________________________________ ___________________________________________________________________________ ABSTRACT Background: Dysregulated appetite control is characteristic of anorexia nervosa (AN) and obesity (OB). Studies using a broad range of methods suggest the cerebellum plays an important role in appetite control, and it is implicated in both AN and OB with reports of aberrant grey matter volume (GMV) compared to non-clinical populations. As functions of the cerebellum are anatomically segregated, specific localization of aberrant anatomy may indicate how it affects appetite control in different states. Objective: To determine if there were consistencies in regions of cerebellar GMV changes affected in AN and OB, and across normative variation. Method: systematic review and meta-analysis using Ginger ALE. Results: Twenty publications were identified as either case-control studies (with total n=619) or regressed weight from normative data against brain volume (with total n=3,518). AN and OB analyses both showed consistently decreased GMV within the left cerebellum, but volume reduction was anterior for AN and posterior for OB, with minimal overlap. Analysis of the normative dataset identified a cluster in right posterior lobe. Discussion: These findings suggest that more than one area of the cerebellum is involved in control of eating behaviour and is differentially affected in normal variation and pathological conditions. Specifically, we hypothesise an association with sensorimotor and emotional learning in AN, but with executive function in OB. Keywords: Meta-analysis, appetite regulation, cerebellum, obesity, anorexia, VBM . CC-BY-ND 4.0 International license It is made available under a is the author/funder, who has granted medRxiv a license to display the preprint in perpetuity. (which was not certified by peer review) The copyright holder for this preprint this version posted April 18, 2022. ; https://doi.org/10.1101/2022.04.14.22273867 doi: medRxiv preprint NOTE: This preprint reports new research that has not been certified by peer review and should not be used to guide clinical practice.