BOSTON, June 11 (UPI) -- Sleep loss exaggerates the degree to which people anticipate impending emotional events, particularly among those highly anxious, U.S. researchers say.
Lead author Andrea Goldstein, a graduate student in the Sleep and Neuroimaging Laboratory at the University of California, Berkeley, and colleagues scanned the brains of 18 healthy adults in two separate sessions -- one after a normal night's sleep and a second after a night of sleep deprivation.
During both sessions, the study participants were exposed to an emotional task that involved a period of anticipating a potentially negative experience -- an unpleasant visual image -- or a potentially benign experience -- a neutral visual image.
The scans using functional magnetic resonance imaging showed sleep deprivation significantly amplified the build-up of anticipatory activity in deep emotional brain centers, especially the amygdala, a part of the brain associated with responding to negative and unpleasant experiences.
In some of these emotional centers of the brain, sleep deprivation detrimentally triggered an increase in anticipatory reaction by more than 60 percent.
"Anticipation is a fundamental brain process, a common survival mechanism across numerous species," Goldstein told Sleep, the 26th annual meeting of the Associated Professional Sleep Societies in Boston. "Our results suggest that just one night of sleep loss significantly alters the optimal functioning of this essential brain process, especially among anxious individuals. This is perhaps never more relevant considering the continued erosion of sleep time that continues to occur across society."