How is Sleep Regulated?

Transitions between wakefulness and sleep are controlled and regulated by the brain, which also plays a key role in directing quantity and depth of sleep. However, sleep is also strongly influenced by external factors, such as light and caffeine.

Features in this section explore the basics of sleep regulation: the structures of the brain that control wakefulness and sleep, the systems that interact to enable us to stay awake and asleep for many hours at a time, and the external factors that can influence both.

Under the Brain's Control

The transition is nearly instantaneous—you're awake one moment, asleep the next. This alteration of consciousness involves a swift but complex interaction between various parts of the brain. Meet the sleep switch and learn about its function. more

The Drive to Sleep and Our Internal Clock

Nodding off throughout the day and night may be normal for cats, but the interaction of two systems ensures that most people enjoy extended periods of wakefulness and sleep each day. more

External Factors that Influence Sleep

Cups of coffee and air travel can alter when and how well we sleep by influencing the sensitive systems that regulate sleep and wakefulness. more