A sleepless night slows down our brain cells, creating mental lapses as we space out at work, at school and behind the wheel.

That's according to a study led by a UCLA neurosurgeon that found sleep deprivation breaks up brain cells' ability to talk with one another, causing mental and visual lags that impair "how we perceive and react to the world around us," said Itzhak Fried, its director.

Such brain farts can prove more consequential than lost keys: The findings show how little society cares about sleep deprivation, he said.

Going without sleep can make you effectively drunk. But, as Fried said in a university release, "no legal or medical standards exist for identifying overtired drivers on the road the same way we target drunk drivers.”

Sleep deprivation has also been linked to obesity, depression and heart attacks, among other risks.

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For the study, published Tuesday in Nature Medicine, scientists analyzed 12 participants with electrodes implanted into their brains. Participants tried to to sort a range of images as quickly as possible. As they did so, their brains fired a total of nearly 1,500 cells.

As participants endured a night without sleep, their performance (and brain cells) slowed. Neurons fired more weakly, Fried said, and communications lagged. More research is needed to determine exactly why brain cells glitch without sleep, according to the university.

Scientists saw one more phenomenon alongside hampered brain activity: slower sleep-like brain waves, which Fried said suggest parts of a tired brain may rest even as other parts remain active.

Follow Josh Hafner on Twitter: @joshhafner