Physiology · Higher Mental Functions, EEG, Sleep and Limbic System

In a healthy young adult, a complete NREM-REM sleep cycle typically lasts approximately:

A 30 minutes
B 60 minutes
C 90 minutes ✓
D 120 minutes

Correct answer: C. 90 minutes

Explanation

A complete NREM-REM sleep cycle in adults lasts approximately 90 minutes. Sleep begins with NREM stages N1, N2, N3, and then REM sleep, with this cycle repeating 4 to 6 times per night. The 90-minute cycle is a fundamental property of human sleep architecture.

Reference: Ganong's Review of Medical Physiology, 26th ed.

High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP

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