During periods of relaxation, while still awake, our brain waves become slower, increase in amplitude and become more synchronous. These types of waves are called alpha waves. For example, such brain waves are often associated with states of relaxation and peacefulness during meditation and biofeedback. As we will see in future lessons, recent evidence indicates that activities that promote alpha wave activity, appear to have positive health benefits.
The first stage of sleep is characterized by theta waves, which are even slower in frequency and greater in amplitude than alpha waves. The difference between relaxation and stage 1 sleep is gradual and subtle.
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