One Sleepless Night Increases Dopamine in the Human Brain“This is the first time that a study provides evidence that in the human brain, dopamine is involved in the adaptations that result from sleep deprivation,” said Nora Volkow, MD, director of the National Institute on Drug Abuse, who led the study. Volkow and colleagues found that in healthy participants, sleep deprivation increased dopamine in two brain structures: the striatum, which is involved in motivation and reward, and the thalamus, which is involved in alertness. The researchers also found that the amount of dopamine in the brain correlated with feelings of fatigue and impaired performance on cognitive tasks. “These findings suggest dopamine may increase after sleep deprivation as a compensatory response to the effects of increased sleep drive in the brain,” said David Dinges, PhD, at the University of Pennsylvania School of Medicine, an expert unaffiliated with the study. “The extent to which this occurs may differentiate how vulnerable people are to the neurobehavioral effects of sleep loss,” Dinges said.