Delta wave

For the medical syndrome, see Wolff–Parkinson–White syndrome. For the television show, see Delta Wave.

A delta wave, recorded in a one-second sample of an EEG (electroencephalograph). This particular wave has a frequency of around 1 Hz.

Delta waves are high amplitude neural oscillations with a frequency between 0.5 and 4 hertz. Delta waves, like other brain waves, can be recorded with electroencephalography (EEG). They are usually associated with the deep stage 3 of NREM sleep, also known as slow-wave sleep (SWS), and aid in characterizing the depth of sleep. Suppression of delta waves leads to impaired body recovery, reduced brain restoration, and poorer sleep.

This is a screenshot of a patient during slow-wave sleep (stage 3). The high amplitude EEG is highlighted in red. This screenshot represents a 30-second epoch (30 seconds of data).