title: Neural mechanisms associated with food motivation in obese and healthy weight adults.
abstract: One out of three adults in the United States is clinically obese. Excess food intake is associated with food motivation, which has been found to be higher in obese compared to healthy weight (HW) individuals. Little is known, however, regarding the neural mechanisms associated with food motivation in obese compared to HW adults. The current study used functional magnetic resonance imaging (fMRI) to examine changes in the hemodynamic response in obese and HW adults while they viewed food and nonfood images in premeal and postmeal states. During the premeal condition, obese participants showed increased activation, compared to HW participants, in anterior cingulate cortex (ACC) and medial prefrontal cortex (MPFC). Moreover, in the obese group, self-report measures of disinhibition were negatively correlated with premeal ACC activations and self-report measures of hunger were positively correlated with premeal MPFC activations. During the postmeal condition, obese participants also showed greater activation than HW participants in the MPFC. These results indicate that brain function associated with food motivation differs in obese and HW adults and may have implications for understanding brain mechanisms contributing to overeating and obesity, and variability in response to diet interventions.
authors.affiliation: Hoglund Brain Imaging Center, University of Kansas Medical Center, Kansas City, Kansas, USA.
authors.forename: Laura E
authors.initials: LE
authors.lastname: Martin
authors.forename: Laura M
authors.initials: LM
authors.lastname: Holsen
authors.forename: Rebecca J
authors.initials: RJ
authors.lastname: Chambers
authors.forename: Amanda S
authors.initials: AS
authors.lastname: Bruce
authors.forename: William M
authors.initials: WM
authors.lastname: Brooks
authors.forename: Jennifer R
authors.initials: JR
authors.lastname: Zarcone
authors.forename: Merlin G
authors.initials: MG
authors.lastname: Butler
authors.forename: Cary R
authors.initials: CR
authors.lastname: Savage
mesh_terms: D001931:Brain Mapping / Q000379:methods; D016022:Case-Control Studies; D002560:Cerebrovascular Circulation; D005215:Fasting; D005247:Feeding Behavior; D005260:Female; D006801:Humans; D006815:Hunger; D008032:Limbic System / Q000098:blood supply / Q000503:physiopathology*; D008279:Magnetic Resonance Imaging; D008297:Male; D009042:Motivation; D009765:Obesity / Q000503:physiopathology* / Q000523:psychology*; D010775:Photic Stimulation; D019518:Postprandial Period; D017397:Prefrontal Cortex / Q000098:blood supply / Q000503:physiopathology*