Obese adults have visual attention bias for food cue images: evidence for altered reward system function

• Published in: International Journal of Obesity Vol. 33; no. 9; pp. 1063 - 1073
• Main Authors: Castellanos, E.H, Charboneau, E, Dietrich, M.S, Park, S, Bradley, B.P, Mogg, K, Cowan, R.L
• Format: Journal Article
• Language: English
• Published: London Nature Publishing Group UK 01.09.2009; Nature Publishing Group
• Subjects: Addictions; Adolescent; Adult; Adults; Attentional bias; Bias; Biological and medical sciences; Brain; Cues; Demographic aspects; Dopamine; Drugs; Eating behavior; eating habits; Epidemiology; Evoked Potentials - physiology; Eye movements; eye tracking; fasting; Fasting - psychology; Feeding Behavior - physiology; Feeding Behavior - psychology; Female; Food; food cues; Food habits; General aspects; Genital system. Mammary gland; Health Promotion and Disease Prevention; Humans; Hunger; Hunger - physiology; image analysis; Influence; Internal Medicine; Investigative techniques, diagnostic techniques (general aspects); Medical imaging; Medical sciences; Medicine; Medicine & Public Health; Metabolic Diseases; Narcotics; Neuroimaging; Obesity; Obesity - physiopathology; Obesity - psychology; original-article; Pathology. Cytology. Biochemistry. Spectrometry. Miscellaneous investigative techniques; Public Health; Reward; Reward (Psychology); reward system; self-report measures; Surveys and Questionnaires; visual probe task; weight control; women; Young Adult; United States > US; Nashville Tennessee; visual probe; human obesity; reward system; incentive salience; eye tracking; Human; Incentive; Obesity; Nutrition; Bias; Nutrition disorder; Metabolic diseases; Image; Probe; Eye; Visual system; Adult; Reward; Nutritional status; Food
• ISSN: 0307-0565; 1476-5497
• DOI: 10.1038/ijo.2009.138

Background: The major aim of this study was to investigate whether the motivational salience of food cues (as reflected by their attention-grabbing properties) differs between obese and normal-weight subjects in a manner consistent with altered reward system function in obesity. Methodology/Principal Findings: A total of 18 obese and 18 normal-weight, otherwise healthy, adult women between the ages of 18 and 35 participated in an eye-tracking paradigm in combination with a visual probe task. Eye movements and reaction time to food and non-food images were recorded during both fasted and fed conditions in a counterbalanced design. Eating behavior and hunger level were assessed by self-report measures. Obese individuals had higher scores than normal-weight individuals on self-report measures of responsiveness to external food cues and vulnerability to disruptions in control of eating behavior. Both obese and normal-weight individuals demonstrated increased gaze duration for food compared to non-food images in the fasted condition. In the fed condition, however, despite reduced hunger in both groups, obese individuals maintained the increased attention to food images, whereas normal-weight individuals had similar gaze duration for food and non-food images. Additionally, obese individuals had preferential orienting toward food images at the onset of each image. Obese and normal-weight individuals did not differ in reaction time measures in the fasted or fed condition. Conclusions/Significance: Food cue incentive salience is elevated equally in normal-weight and obese individuals during fasting. Obese individuals retain incentive salience for food cues despite feeding and decreased self-report of hunger. Sensitization to food cues in the environment and their dysregulation in obese individuals may play a role in the development and/or maintenance of obesity.