The stage of sleep in which delta waves begin to appear is ________ sleep.

Question

Quizplus · Accepted Answer

Delta waves are associated with deep sleep, also known as slow-wave sleep (SWS). The appearance of delta waves marks the transition from stage 2 to stage 3 of sleep, which is often referred to as stage 3 or stage 4 interchangeably. However, the American Academy of Sleep Medicine now classifies them as a single stage, so stage 3 is the correct answer. Stage 1 and 2 are lighter stages of sleep with less prominent brainwave activity, while stage 5 is REM sleep with rapid eye movements and heightened brain activity.

The Stage of Sleep in Which Delta Waves Begin to Appear