Dreaming without REM sleep

Conscious Cogn. 2012 Sep;21(3):1129-40. doi: 10.1016/j.concog.2012.04.010. Epub 2012 May 29.


To test whether mental activities collected from non-REM sleep are influenced by REM sleep, we suppressed REM sleep using clomipramine 50mg (an antidepressant) or placebo in the evening, in a double blind cross-over design, in 11 healthy young men. Subjects were awakened every hour and asked about their mental activity. The marked (81%, range 39-98%) REM-sleep suppression induced by clomipramine did not substantially affect any aspects of dream recall (report length, complexity, bizarreness, pleasantness and self-perception of dream or thought-like mentation). Since long, complex and bizarre dreams persist even after suppressing REM sleep either partially or totally, it suggests that the generation of mental activity during sleep is independent of sleep stage.

Publication types

  • Clinical Trial

MeSH terms

  • Adult
  • Antidepressive Agents, Tricyclic / pharmacology
  • Clomipramine / pharmacology
  • Cross-Over Studies
  • Double-Blind Method
  • Dreams* / drug effects
  • Humans
  • Male
  • Mental Recall
  • Polysomnography
  • Sleep Stages* / drug effects
  • Sleep, REM* / drug effects
  • Young Adult


  • Antidepressive Agents, Tricyclic
  • Clomipramine