Investigators say their findings show that sleep loss markedly exaggerates the degree to which we anticipate impending emotional events. This overreaction often occurs among highly anxious people, making them especially vulnerable.
Experts say that two common features of anxiety disorders are sleep loss and an amplification of emotional response. Findings from this new study suggest that these features may not be independent of one another but may interact instead.
University of California, Berkeley researchers used brain scanning on 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, 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).
Functional magnetic resonance imaging (fMRI) showed that 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.
Amazingly, in some of these emotional centers of the brain, sleep deprivation detrimentally triggered an increase in anticipatory reaction by more than 60 percent.
In addition, the researchers found that the strength of this sleep deprivation effect was related to how naturally anxious the participants were.
People who were more anxious showed the greatest vulnerability to the aggravating effects of sleep deprivation. The results suggest that anxiety may significantly elevate the emotional dysfunction and risk associated with insufficient sleep.
“Anticipation is a fundamental brain process, a common survival mechanism across numerous species,” said Andrea Goldstein, lead author of the study.
“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.”