Randy Gardner stayed awake for 11 days in a 1965 experiment to see how long he could go without sleep. By day 3, he was moody, uncoordinated, and struggling with memory and concentration. While he recovered without damage, lack of sleep can cause harm like hormonal imbalance, illness, and even death in extreme cases. Adults need 7-8 hours of sleep per night and adolescents need about 10 hours. When we don't get enough sleep, learning, memory, mood, and reaction time are negatively impacted. A devoted soccer fan died in 2014 after staying awake for 48 hours to watch the World Cup due to a stroke, which is linked to chronic sleep deprivation. The brain's glymphatic system clears