BOSTON—Sleep loss impairs the brain’s ability to integrate appetitive information, and thus makes it more difficult for people to choose healthy foods to eat, according to a study presented at the 26th Annual Meeting of the Associated Professional Sleep Societies.
After a night of sleep deprivation, brain activity in study participants’ frontal lobe was impaired, and networks governing appetitive food stimulus evaluation appeared to be disrupted.
Stephanie Greer, a graduate student at the Sleep and Neuroimaging Laboratory at the University of California, Berkeley, conducted an imaging study to investigate the effect of sleep deprivation on central brain mechanisms underlying food appraisal. She and her colleagues recruited eight healthy adults ages 18 to 25, eight of whom were female, for two MRI sessions during which they rated their current desire for 80 foods. The first session was conducted after a night of normal sleep, and the second was conducted after 24 hours without sleep in a repeated-measures cross-over design. The investigators took subjective taste ratings from the participants after each scan.
“Sleep deprivation selectively and significantly impaired activity in high-order regions known to integrate affective signals, specifically the right anterior insula and dorsal anterior cingulate, in response to desired foods,” said Ms. Greer. She and her colleagues observed equivalent reactivity in classical subcortical reward regions and basic taste-perception networks, such as the medial orbital-frontal cortex, the middle insula, and the caudate.
In addition, sleep deprivation decreased the correlation between food desire and taste ratings. This result, which was consistent with a failure of appetitive signal integration, indicated a decreased ability to determine food desire based on taste value. The researchers did not observe any differences in mean ratings of food desire or taste value.
“These results shed light on how the brain becomes impaired by sleep deprivation, leading to improper food choices,” said Ms. Greer. The study findings also provide a mechanistic brain link between sleep loss and obesity and may be valuable to public health researchers, she added.