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Deepening Sleep by Hypnotic Suggestion

hypnosis hypnosis-sleep-study

Can hypnosis help you get deep sleep? The University of Zurich, Switzerland tested this hypothesis and found that hypnotic suggestion can, indeed, increase deep sleep.


  • Getting a good, deep sleep, (technically called slow-wave sleep (SWS)) is critical to your mind and body. You need SWS for brain plasticity, which helps you learn and change your behaviors accordingly, and to restore your physical body.
  • The study gave one group of females a hypnotic sleep suggestion audio and the control group a placebo audio just before both groups napped. The study then used a high-density EEG to record the brain activity of both groups while they napped.
  • The result? When they compared the group that received the hypnotic suggestion to the control group, they found that the group that received the hypnotic suggestion:
    • had an 81% increase of SWS
    • had significantly enhanced SWS
    • plus, they slept longer: their time awake was 67% of the time awake of the control group.

"Our results demonstrate the effectiveness of hypnotic suggestions to specifically increase the amount and duration of slow wave sleep (SWS) in a midday nap using objective measures of sleep in young, healthy, suggestible females. Hypnotic suggestions might be a successful tool with a lower risk of adverse side effects than pharmacological treatments to extend SWS also in clinical and elderly populations."