Which brain waves indicate the deepest stage of sleep?

Delta waves are known to indicate the deepest stage of sleep, specifically during non-REM sleep. These brain waves are characterized by their low frequency and high amplitude, which are distinctly different from the higher frequency brain waves present during wakefulness and lighter stages of sleep.

During the deepest stage of sleep, which is often referred to as slow-wave sleep (SWS), delta waves dominate the EEG readings. This stage of sleep is crucial for physical restoration, immune function, and overall health. It is during this time that the body engages in processes like tissue repair and growth, making delta waves significant for restorative sleep.

The other types of brain waves, such as alpha, theta, and gamma waves, are associated with different states of consciousness or levels of alertness. Alpha waves typically occur when a person is awake but relaxed, theta waves are present in light sleep or deep relaxation, and gamma waves are linked to higher cognitive functions and active mental processing.