Skip to main content
Intermediate Technical IVT

NREM sleep

Pronunciation: NON-rem

Also written as: NREM — Non-Rapid Eye Movement

Non-rapid eye movement sleep comprising the deeper, more restorative phases of the sleep cycle.

Full Definition

NREM (Non-Rapid Eye Movement) sleep represents approximately 75-80% of total sleep time in healthy adults and consists of three distinct stages: N1 (light sleep), N2 (stable sleep), and N3 (deep sleep or slow-wave sleep). NREM sleep is characterized by reduced brain activity, slower heart rate, decreased body temperature, and minimal eye movement. This sleep state is considered primarily restorative, with important functions including memory consolidation, tissue repair, and growth hormone release. NREM sleep stages are distinguished from REM sleep by their characteristic electroencephalographic patterns and physiological features.

Usage

Usage note: Always spell out as NREM rather than 'non-REM' in formal documentation; maintain consistent capitalization.

In Context

  • "The sleep study showed reduced NREM sleep stage 3, indicating possible sleep fragmentation." — Polysomnography interpretation
  • "NREM sleep abnormalities were associated with the patient's cognitive complaints." — Clinical correlation

Also known as

non-REM sleep quiet sleep

Contrasted with

REM sleep active sleep

Don't confuse with

REM sleep deep sleep slow-wave sleep

Editors from these organisations have used our services since 1998

Reuters BBC Oxford University Press Penguin Random House Springer Microsoft Suncor Energy United Nations Fisher Investments IBM The Home Depot KODAK CHEVRON