A stage of sleep that occurs approximately every 90 minutes, marked by bursts of rapid eye movements occurring under closed eye lids. REM sleep periods are associated with dreaming.

Quite Simply..

  • REM Sleep causes rapid eye movements that occur about every 90 minutes during sleep.
  • The voluntary muscles in the rest of the body are immobile, paralyzed during REM sleep (sleep paralysis).
  • The longer someone sleeps, the longer each REM session lasts. For example, the first REM session could last 5 minutes, while the fifth REM could last up to an hour.
  • REM Sleep is the closest stage to being conscious and awake.
  • This would be known as the part of sleep where dreams occur.
  • This is the time of sleep that deals with dreams.

Examples of REM Sleep

  • In a study where REM sleepers were awoken and asked to describe their mental activity, individuals reported vivid cognitions featuring fanciful, bizarre scenes.
  • The dream state, where you could be dreaming about ponies or the biggest rollercoaster ever.
  • By depriving one of REM sleep, then sleeping will cause an increase of REM time from 90 minutes to 120 minutes or more which is called a REM rebound.
  • REM lets your body rest (sleep paralysis) while your mind is active.
  • New-borns spend about 50% of their sleep in REM, but older adults spend only about 15% in REM



  1. Effects of Stimuli on Dreams (waking REM)
      • In an experiment done by Dement and Wolpert, the effect of external sensory stimuli was tested on sleeping subjects. Researchers used four stimuli: a pure tone rung for five seconds, a flash of bright light, a spray of cold water, and a doorbell. In about 25% of cases, the subjects reported some type of incorporation of the stimulation into their dreams. Incorporations of the tone among different subjects include a brief roaring sound, an earthquake, and a plane crash in dreams. The flash of light was interpreted as a sudden fire, lightning, a flashlight, or shooting stars. The spray of cold water was a sudden rainfall, a squirt, leaking roofs. Lastly, the doorbell appeared as a ringing phone or simply a doorbell. This is the only reputable and cohesive study found on the topic, which leads us to believe that this phenomena is not yet experimentally solidified enough to be absolutely named. There were however, many personal reports dealing with this concept. A guess is that it's a fairly widespread experience whose reason or cause psychologists are still trying to decipher (partly because it's somewhat difficult to interpret results). It would be interesting to learn more about this experience from a biological standpoint.

Additional Information