title: Independent functional connectivity networks underpin food and monetary reward sensitivity in excess weight.
abstract: Overvaluation of palatable food is a primary driver of obesity, and is associated with brain regions of the reward system. However, it remains unclear if this network is specialized in food reward, or generally involved in reward processing. We used functional magnetic resonance imaging (fMRI) to characterize functional connectivity during processing of food and monetary rewards. Thirty-nine adults with excess weight and 37 adults with normal weight performed the Willingness to Pay for Food task and the Monetary Incentive Delay task in the fMRI scanner. A data-driven graph approach was applied to compare whole-brain, task-related functional connectivity between groups. Excess weight was associated with decreased functional connectivity during the processing of food rewards in a network involving primarily frontal and striatal areas, and increased functional connectivity during the processing of monetary rewards in a network involving principally frontal and parietal areas. These two networks were topologically and anatomically distinct, and were independently associated with BMI. The processing of food and monetary rewards involve segregated neural networks, and both are altered in individuals with excess weight.
authors.affiliation: Institute of Neuroscience F. Olóriz, Red de Trastornos Adictivos and Mind, Brain, and Behavior Center-CIMCYC, Universidad de Granada, Granada 18071, Spain.
authors.forename: Juan
authors.initials: J
authors.lastname: Verdejo-Román
authors.affiliation: Brain and Mental Health Laboratory, Monash Institute of Cognitive and Clinical Neurosciences and Monash Biomedical Imaging, Monash University, Melbourne, Victoria 3168, Australia.
authors.forename: Alex
authors.initials: A
authors.lastname: Fornito
authors.affiliation: Department of Psychiatry, Bellvitge University Hospital-IDIBELL, Hospitalet de Llobregat, Barcelona 08907, Spain; CIBERSAM, Carlos III Health Institute, Barcelona 08907, Spain; Department of Psychobiology and Methodology in Health Sciences, Universitat Autònoma de Barcelona 08193, Spain.
authors.forename: Carles
authors.initials: C
authors.lastname: Soriano-Mas
authors.affiliation: Institute of Neuroscience F. Olóriz, Red de Trastornos Adictivos and Mind, Brain, and Behavior Center-CIMCYC, Universidad de Granada, Granada 18071, Spain.
authors.forename: Raquel
authors.initials: R
authors.lastname: Vilar-López
authors.affiliation: School of Psychological Sciences and Monash Institute of Cognitive and Clinical Neurosciences, Monash University, Melbourne, Victoria 3800, Australia. Electronic address: antonio.verdejo@monash.edu.
authors.forename: Antonio
authors.initials: A
authors.lastname: Verdejo-García
mesh_terms: D000328:Adult; D001921:Brain / Q000502:physiology / Q000503:physiopathology*; D001931:Brain Mapping; D002755:Choice Behavior / Q000502:physiology*; D005260:Female; D005502:Food; D005518:Food Preferences; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D009434:Neural Pathways / Q000502:physiology / Q000503:physiopathology; D009765:Obesity / Q000503:physiopathology*; D011930:Reaction Time; D012201:Reward
keywords: Food reward; Functional connectivity networks; Monetary reward; Obesity; fMRI