Which statement best describes the typical sleep pattern for a normal adult?

• A. A normal adult remains in deep non-REM sleep for the entire night without entering REM sleep.
• B. A normal adult wakes up every 30 minutes during the night and does not experience sleep cycles.
• C. A normal adult only experiences REM sleep and does not cycle through other sleep stages.
• D. A normal adult cycles through several stages of sleep, including REM and non-REM, in approximately 90-minute intervals throughout the night.

Answer: (D)

Verified step by step guidance

1. Understand that normal adult sleep consists of multiple stages, primarily categorized into REM (Rapid Eye Movement) sleep and non-REM sleep.
2. Recognize that sleep is organized into cycles, each lasting about 90 minutes, during which the sleeper progresses through different stages of non-REM sleep followed by a period of REM sleep.
3. Note that deep non-REM sleep (also called slow-wave sleep) occurs during the earlier part of the night and is not continuous throughout the entire sleep period.
4. Acknowledge that adults typically do not wake up every 30 minutes; instead, they experience relatively stable sleep cycles with brief awakenings that are usually not remembered.
5. Conclude that the best description of a normal adult's sleep pattern is one that includes cycling through several stages of sleep, including both REM and non-REM stages, in approximately 90-minute intervals.