What level of sleep restriction sustained over several days leads to a cognitive deficit equivalent to being awake for 24 hours straight?

Answer

Operating on just four to five hours of sleep per night

Operating on four to five hours of sleep per night for several consecutive days causes a measurable cognitive deficit that is comparable to the impairment experienced after being awake for a full 24 hours.

What level of sleep restriction sustained over several days leads to a cognitive deficit equivalent to being awake for 24 hours straight?
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