During a normal night's sleep, there are five different stages of sleep. The first two stages are considered light, shallow stages of sleep. Stages three and four are considered to be the deeper, restorative stages. Stage five is REM sleep. REM sleep is the stage where dreams occur.
During REM sleep, while we are dreaming, our brain patterns are similar to those we experience while we are awake.
During deep sleep, the heart rate, breathing, blood pressure and body temperature reach their lowest levels of the day.
Most adults need about eight hours of sleep to function at their best. Studies have shown that most adults only get six to seven hours of sleep per night.
Many people who suffer from insomnia also suffer from anxiety and depression.
Our large body muscles are paralyzed during sleep.
Cats sleep up to 18 hours per day while giraffes usually sleep not more than about 20 minutes each day.
It is more difficult to wake a child than an adult from deep sleep.
Too little sleep for long periods of time can lead to hallucinations.
Women and older people suffer from insomnia most often.
Even during a deep sleep, we can still pick up sounds and signals from the world around us. This explains why we can sleep through a howling storm but will hear a door open or a baby cry.
The average person wakes up about six times per night.