This image depicts the sleep cycles over the course of a typical night. In which stage do delta brain waves exceed 50 percent of total brain activity?
A)stage 1 NREM
B)stage 2 NREM
C)REM sleep
D)stage 4 NREM

Question

This image depicts the sleep cycles over the course of a typical night. In which stage do delta brain waves exceed 50 percent of total brain activity? 
A)stage 1 NREM 
B)stage 2 NREM 
C)REM sleep 
D)stage 4 NREM

Quizplus · Accepted Answer

Delta brain waves, also known as slow-wave sleep, are most prominent in stage 4 NREM sleep. Therefore, the correct answer is D.

This Image Depicts the Sleep Cycles Over the Course of a Typical