Sleep deprivation can affect people in a similar way to alcohol, scientists warn.
They say being over-tired increases the risk of hypertension, diabetes, obesity, heart attack, and stroke. It also disrupts the way brain cells transmit information as exhausted neurons respond more slowly than usual.
The researchers tested 12 epileptic patients who had electrodes implanted into their brains to pinpoint the origin of their seizures.
Professor Itzhak Fried said: “We discovered that starving the body of sleep robs neurons of the ability to function properly.”
“It exerts a similar influence on our brain as drinking too much. Yet no legal or medical standards exist for identifying over-tired drivers the same way we target drunk drivers.”
The study participants had to stay awake all night to speed up the onset of an epileptic episode. Lack of sleep is known to trigger seizures in vulnerable individuals.
Patients in the study then had to identify images as fast as possible while the implants recorded brain activity.
The lack of sleep caused the neurons to respond sluggishly, the study published in Nature Medicine found.
Fried, of the University of California, added: “It appears select regions of the patients’ brains were dozing, causing mental lapses.”