Which of the following statements about the sleep cycle is TRUE?
A. NREM sleep always precedes REM sleep.

B. REM sleep occurs only once per night.

C. Adults typically experience four to six sleep cycles per night.

D. NREM sleep stages are all equally restorative.

E. Infants spend more time in NREM sleep than adults.

Choose the correct answer from the options given below:

The correct answer is 'A, C, and E Only'

Key Points

• The sleep cycle:
  • The sleep cycle is a complex pattern of alternating non-rapid eye movement (NREM) and rapid eye movement (REM) sleep that occurs throughout the night.
  • Understanding the sleep cycle is important for recognizing how sleep quality and quantity impact overall health and well-being.
• A. NREM sleep always precedes REM sleep:
  • This statement is true. A typical sleep cycle begins with NREM sleep, which progresses through its stages before transitioning into REM sleep.
  • NREM sleep includes stages 1, 2, 3, and sometimes 4, with each stage representing a deeper level of sleep.
• C. Adults typically experience four to six sleep cycles per night:
  • This statement is true. On average, adults go through about four to six sleep cycles each night, with each cycle lasting approximately 90 minutes.
  • The number of cycles can vary depending on the individual and the total amount of sleep they get.
• E. Infants spend more time in NREM sleep than adults:
  • This statement is true. Infants spend a higher proportion of their sleep in REM sleep compared to adults, but they also have longer overall sleep durations, leading to more time spent in both NREM and REM sleep stages.
  • Sleep patterns change significantly from infancy to adulthood.

Additional Information

• B. REM sleep occurs only once per night:
  • This statement is incorrect. REM sleep occurs multiple times throughout the night, typically at the end of each sleep cycle.The duration of REM sleep periods increases as the night progresses.
• D. NREM sleep stages are all equally restorative:
  • This statement is incorrect. Not all NREM sleep stages are equally restorative. Deep sleep (stages 3 and 4) is considered the most restorative phase, crucial for physical recovery and growth.
  • Light sleep stages (1 and 2) are less restorative but are important for the overall sleep architecture and progression into deeper sleep stages.