Daytime sleepiness affects prefrontal regulation of food intake

• Published in: NeuroImage (Orlando, Fla.) Fla.), 2013-05, Vol.71, p.216-223
• Main Authors: Killgore, William D.S., Schwab, Zachary J., Weber, Mareen, Kipman, Maia, DelDonno, Sophie R., Weiner, Melissa R., Rauch, Scott L.
• Format: Article
• Language: English
• Subjects: Adolescent; Adult; Appetite; Biological and medical sciences; Body mass index; Brain Mapping; Eating - physiology; Female; fMRI; Food; Fundamental and applied biological sciences. Psychology; Gender differences; Humans; Magnetic Resonance Imaging; Male; Middle Aged; Neuroimaging; Obesity; Prefrontal cortex; Prefrontal Cortex - physiology; Sex Characteristics; Sex differences; Sleep; Sleep - physiology; Sleep deprivation; Sleep. Vigilance; Sleepiness; Vertebrates: nervous system and sense organs; Young Adult
• ISSN: 1053-8119; 1095-9572
• DOI: 10.1016/j.neuroimage.2013.01.018

The recent epidemic of obesity corresponds closely with the decline in the average number of hours of sleep obtained nightly. While growing research suggests that sleep loss may affect hormonal and other physiological systems related to food intake, no studies have yet explored the role that sleepiness may play in reducing prefrontal inhibitory control over food intake. Because evidence suggests that women may be more prone to obesity and eating disorders, as well as more likely to suffer from sleep problems, we examined the relation between general daytime sleepiness, brain responses to food stimuli, and self-reported overeating separately for men and women. Thirty-eight healthy adults (16 women; 22 men) aged 18 to 45 underwent functional magnetic resonance imaging (fMRI) while viewing pictures of high- and low-calorie foods. Subjects completed the Epworth Sleepiness Scale (ESS) and provided a rating to the query “how often do you eat more than you intend to.” Contrast images comparing brain activation derived from the high- versus low-calorie conditions were correlated voxel-wise with scores from the ESS in a second-level regression model, the output of which was used to predict self-reported overeating. As hypothesized, daytime sleepiness correlated with reduced activation in the ventromedial prefrontal cortex during perception of high- versus low-calorie food images. Moreover, activation within this cluster predicted overeating, but only for women. Findings suggest that normal fluctuations in sleepiness may be sufficient to affect brain regions important for regulating food intake, but that these effects may differ between men and women. ► Functional magnetic resonance imaging data were acquired in healthy men and women. ► During imaging, participants viewed images of high- and low-calorie foods. ► Sleepiness correlated negatively with ventromedial prefrontal cortex activity. ► Prefrontal cluster activation predicted the tendency to overeat during meals. ► Sleepiness may contribute to overeating by reducing prefrontal brain functioning.