How long can you go without sleep?

On 28 December 1963, Randy Gardner, a 17-year-old schoolboy in San Diego, California, got up at 6 am feeling wide awake and raring to go. He didn’t go back to sleep again until the morning of 8 January 1964. That’s 11 days without sleep.

Gardner’s 264 hours remains the longest scientifically verified period without sleep, breaking the previous record of 260 hours. It was described in a 1965 paper by sleep researcher William Dement of the Stanford University School of Medicine in California, who stayed awake with Gardner for the final three days. Gardner experienced mood swings, memory and attention lapses, loss of coordination, slurred speech and hallucinations, but was otherwise fine. His first sleep after those 11 days lasted just 14 hours.