title: Processing of food pictures: influence of hunger, gender and calorie content.
abstract: In most cases obesity, a major risk factor for diabetes mellitus type 2 and other associated chronic diseases, is generated by excessive eating. For a better understanding of eating behavior, it is necessary to determine how it is modulated by factors such as the calorie content of food, satiety and gender. Twelve healthy normal weighted participants (six female) were investigated in a functional magnetic resonance imaging (fMRI) study. In order to prevent the influence of social acceptability, an implicit one-back task was chosen for stimulus presentation. We presented food (high- and low-caloric) and non-food pictures in a block design and subjects had to indicate by button press whether two consecutive pictures were the same or not. Each subject performed the task in a hungry and satiated state on two different days. High-caloric pictures compared to low-caloric pictures led to increased activity in food processing and reward related areas, like the orbitofrontal and the insular cortex. In addition, we found activation differences in visual areas (occipital lobe), despite the fact that the stimuli were matched for their physical features. Detailed investigation also revealed gender specific effects in the fusiform gyrus. Women showed higher activation in the fusiform gyrus while viewing high-caloric pictures in the hungry state. This study shows that the calorie content of food pictures modulates the activation of brain areas related to reward processing and even early visual areas. In addition, satiation seems to influence the processing of food pictures differently in men and women. Even though an implicit task was used, activation differences could also be observed in the orbitofrontal cortex, known to be activated during explicit stimulation with food related stimuli.
authors.affiliation: MEG-Center, University of Tübingen, Tübingen, Germany. sabine.frank@med.uni-tuebingen.de
authors.forename: Sabine
authors.initials: S
authors.lastname: Frank
authors.forename: Naima
authors.initials: N
authors.lastname: Laharnar
authors.forename: Stephanie
authors.initials: S
authors.lastname: Kullmann
authors.forename: Ralf
authors.initials: R
authors.lastname: Veit
authors.forename: Carlos
authors.initials: C
authors.lastname: Canova
authors.forename: Yiwen Li
authors.initials: YL
authors.lastname: Hegner
authors.forename: Andreas
authors.initials: A
authors.lastname: Fritsche
authors.forename: Hubert
authors.initials: H
authors.lastname: Preissl
mesh_terms: D000328:Adult; D001921:Brain / Q000502:physiology*; D001931:Brain Mapping; D003463:Cues; D005260:Female; D005502:Food; D006801:Humans; D006815:Hunger / Q000502:physiology*; D007091:Image Processing, Computer-Assisted; D008279:Magnetic Resonance Imaging; D008297:Male; D010775:Photic Stimulation; D011930:Reaction Time / Q000502:physiology; D012201:Reward; D012527:Satiation / Q000502:physiology*; D012737:Sex Factors