Why do we sleep? What happens during sleep? What do dreams mean?
Nap for Performance?
Most of us today adhere to a similar cycle of sleep. Staying awake through the day, we sleep through the night, when the absence of daylight makes outdoor activities impractical. This circadian rhythm is regulated by light sources in our environment, such as the Sun. The common practise of sleeping for just one continuous period daily - at night - is known...
If you believe the evolutionary theory of sleep, you might be wondering why humans, not just non-human animals, still do it. There are famous examples of people being able to live on just a fraction of the sleep the rest of us have. For example, ex-British prime minister Margaret Thatcher was thought to have as little as 4 hours of sleep...
Common disorders associated with sleep.
Stages of Sleep
A look at the stages of sleep we experience at night.