REM sleep accounts for approximately what percentage of a typical adult sleep?

REM sleep accounts for approximately what percentage of a typical adult sleep?

• A. 5-15%
• B. 40-50%
• C. 0-5%
• D. 20-25%

Answer: (D)

REM sleep is the phase where dreaming often occurs and brain activity looks awake, but the body is paralyzed. Throughout a night, sleep cycles repeat about every 90 minutes, with REM showing up in each cycle and the periods lengthening as the night goes on. Because you accumulate several REM periods, total REM time in a typical eight-hour sleep is about 1.5 to 2 hours, which works out to roughly 20–25% of total sleep. That’s why the best estimate for adults is around one-fifth to one-quarter of sleep spent in REM. The other options are either too small or too large for a healthy adult's sleep pattern.

REM sleep is the phase where dreaming often occurs and brain activity looks awake, but the body is paralyzed. Throughout a night, sleep cycles repeat about every 90 minutes, with REM showing up in each cycle and the periods lengthening as the night goes on. Because you accumulate several REM periods, total REM time in a typical eight-hour sleep is about 1.5 to 2 hours, which works out to roughly 20–25% of total sleep. That’s why the best estimate for adults is around one-fifth to one-quarter of sleep spent in REM. The other options are either too small or too large for a healthy adult's sleep pattern.