You must have heard one should sleep for eight hours, but researchers say that it depends on a person's genetics. When it comes to sleep, quality matters over quantity. People with Familial Natural Short Sleep (FNSS) prefer to sleep just four to six hours a night, and yet have the ability to function fully on.

According to researchers at University of California, San Francisco, these "elite sleepers" show psychological resilience and resistance to neurodegenerative conditions that may point the way to fending off neurological disease.