How is Sleep Regulated?
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The Brain and Sleep [2:04]
Dr. Thomas Scammell discusses how structures and chemicals in the brain function to produce both wakefulness and sleep.
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The Forces that Define Sleep and Wakefulness
Two systems interact to enable most people to stay awake and fall asleep when they choose to.
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Alcohol and Sleep [0:26]
Dr. Stephen Amira describes how alcohol consumption can lead to disrupted sleep.
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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