Most people have had a time when they have slept little. The next day, we have the feeling that on a cognitive level we are slower. A study that analyzed the sleep of more than 10.000 people, determined that people who slept less or more than 7-8 hours showed poorer cognitive performance. Sleeping 4 hours a night was equivalent to 8 years of aging!
These results show the importance of sleep for optimal performance.
