One Sleepless Night Increases Dopamine In The Human Brain
Just one night without sleep can increase the amount of the chemical dopamine in the human brain, according to new imaging research in the August 20 issue of The Journal of Neuroscience. Because drugs that increase dopamine, like amphetamines, promote wakefulness, the findings offer a potential mechanism explaining how the brain helps people stay awake despite the urge to sleep.
However, the study also shows that the increase in dopamine cannot compensate for the cognitive deficits caused by sleep deprivation.
"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.
