title: Acquired differences in brain responses among monozygotic twins discordant for restrained eating.
abstract: We studied whether self-reported intent to exert cognitive control over eating was associated with differences in brain response to food cues, independent of genetic background. Subjects were ten pairs of identical twins in which one twin was a restrained eater and the co-twin was unrestrained, as classified by the Herman and Polivy Restraint Scale. Before and after ingestion of a milkshake, we used functional magnetic resonance imaging to measure brain response to photographs of objects, "fattening" food, and "non-fattening" food. At baseline, restrained eaters had greater activation in the left amygdala and the right thalamus in response to fattening food cues than did their unrestrained co-twins. When restrained eaters drank a milkshake, activation in response to fattening food photographs decreased across multiple brain areas, whereas activation induced by non-fattening food photographs increased. As compared to their unrestrained co-twins, restrained eaters who drank a milkshake had greater decreases in activation by fattening food images in the left amygdala and occipital lobe, and greater increases in activation by non-fattening food images in the medial orbitofrontal cortex. Because of the discordant monozygotic twin study design, the findings provide a rigorous level of support for the hypothesis that adopting an intention to restrain eating alters brain response to food cues.
authors.affiliation: Division of General Internal Medicine, Department of Medicine, University of Washington School of Medicine, Seattle, WA, United States. ellschur@u.washington.edu
authors.forename: Ellen A
authors.initials: EA
authors.lastname: Schur
authors.forename: Natalia M
authors.initials: NM
authors.lastname: Kleinhans
authors.forename: Jack
authors.initials: J
authors.lastname: Goldberg
authors.forename: Dedra S
authors.initials: DS
authors.lastname: Buchwald
authors.forename: Janet
authors.initials: J
authors.lastname: Polivy
authors.forename: Angelo
authors.initials: A
authors.lastname: Del Parigi
authors.forename: Kenneth R
authors.initials: KR
authors.lastname: Maravilla
mesh_terms: D000328:Adult; D000368:Aged; D001835:Body Weight / Q000235:genetics; D001921:Brain / Q000098:blood supply / Q000502:physiology*; D001931:Brain Mapping; D003463:Cues; D004327:Drinking Behavior / Q000502:physiology; D005247:Feeding Behavior / Q000523:psychology*; D005260:Female; D005508:Food Deprivation; D005518:Food Preferences; D006801:Humans; D007091:Image Processing, Computer-Assisted; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D010100:Oxygen / Q000097:blood; D016037:Single-Blind Method; D014430:Twins, Monozygotic; D055815:Young Adult
chemical_list: D010100:Oxygen