Is there anything better than a good night’s rest?
People who can get by on four hours of sleep sometimes brag about their strength and endurance. But recent scientific studies show that a lack of sleep causes many significant changes in the body and increases your risk for serious health concerns such as obesity, disease, and even early death.
Seven to eight hours for longevity
The healthy amount of sleep for the average adult is around seven to eight hours each night. Researchers in the United Kingdom and Italy analyzed data from 16 separate studies conducted over 25 years, covering more than 1.3 million people and more than 100,000 deaths. They published their findings in the journal Sleep. Those who generally slept for less than six hours a night were 12 percent more likely to experience premature death. People who slept more than eight to nine hours per night had an even higher risk, at 30 percent.
Researchers also found that people who reduced their sleep time from seven hours to five hours or less had 1.7 times the risk of death from all causes.
When looking for increased creativity, getting more REM sleep is a key. Most of your REM sleep, the time in which you dream, takes place during the last four hours of an eight-hour period.
Significance of REM Sleep
There is a wealth of evidence that during REM sleep, your brain does essential work that supports regular brain function.
We tend to dream about what happened in the recent past – indeed, most frequently about what happened the previous day. Early in the evening, those dreams will tend to be very literal; later in the evening, the dreams tend to become more abstract.
• This replay and abstraction process is critical to optimal memory, high-level creativity, and problem-solving ability. What’s more, those memories seem to be consolidated during the following night of REM sleep. If you prevent someone from getting REM sleep, detailed memory for experiences and learning will suffer. Cognitive function also declines.
• Your brain needs REM sleep like it needs nutritious food. The vast majority of your REM sleep takes place in the last two sleep cycles of an eight-hour sleep session. If you reduce your sleep by a couple of hours a night, you might feel you’ve still gotten most of a good night’s sleep. In terms of total hours, that’s correct: You’ve only missed out on about 25 percent of your sleep time. But in terms of REM sleep time, you may have cut the benefits by 40 percent.
In addition to helping you focus, sleep helps protect and strengthen your memory, which enhances your creative thinking. Research shows that sleeping after learning can help with memory retention. It also reduces interference from external events. People who are sleep-deprived:
• have a harder time receiving information due to the brain’s overworked neurons
• may interpret events differently
• tend to have impaired judgment
• lose their ability to access previous information
It’s important to get seven to eight hours of sleep so that you can experience all the sleep stages. No one stage is responsible for memory and learning. Two stages (rapid eye movement and slow wave sleep) contribute to:
• creative thinking
• procedural memory
• long-term memories
• memory processing