Give Now

A Moment of Science

How Time Passes In Dreams

So how many minutes or hours pass during a dream? Find out on this Moment of Science.

Trippy dreamscape

Photo: h.koppdelaney (flickr)

Although sometimes people think their dreams seem to last a long time, one scientist concluded that "dream time" is similar in length to real time

Many people believe that hours worth of events and activities can be dreamed about in a matter of seconds. Despite this common belief about how we dream, time in dreams actually is not compressed. If you dream of an activity that would take five minutes in waking life, you probably dream about it for a full five minutes.

Dream Time Vs. Real Time

Dream and sleep researcher William Dement conducted two studies that demonstrated that dream time was similar to real time. Because dreamers’ eyes move under their eyelids very rapidly while they are dreaming, Dement was able to monitor sleepers and record the length of their dreams by observing their rapid eye movement.

After recording this information, Dement would wake dreamers and have them write down a description of their most recent dream. He assumed that longer dreams would take more words to describe than shorter ones.

Word Count

When he compared the number of words in each dream report with the number of minutes the dream had occurred, he found that the longer the dream, the more words the dreamer used to describe it.

In another related experiment, Dement woke sleepers while they were dreaming and asked them how long they perceived their most recent dream had taken. Eighty-three percent of the time they perceived correctly whether their dreams had been going on for a long time or for a short time.

With these experiments, Dement concluded that time in dreams is nearly identical to time in waking life. So the next time in your dreams you slay a dragon or fly from your house to your workplace, the amount of time it seemed to take is probably just about how long it actually took to dream it.

  • Pingback: Why Is It So Difficult To Remember Our Dreams? | A Moment of Science - Indiana Public Media

  • KYousuf1400

    No offense to William Dement but I cannot see how these experiments have established anything other then that dreamers know the difference between a long dream and a shorter one in real time. Jumping to the conclusion that this somehow proves that dream time and real time are the same or even similar sounds silly. 

    For example, he asks the dreamers in the second experiment how long did their dream seem to last. He then comes across the astonishing fact that they perceive a longer dream as….. A longer dream (wow).
    No mention is made of the actual estimations that the dreamers made for their dream . I would like a mention made of a estimation of a dreamer vs the actual period of the REM cycle of a dream.

    I would just check the raw data of his study but I can’t seem to find it. As the results of his studies are presented here, I maintain that this does not suggest anything but a positive relationship between subjective length and objective length in dreams.

  • Simone Schwendimann

    Hi there! Could you please indicate the exact title of Mr. Dement’s research paper summarised in this passage. Thank you! :)

  • Jennifer M.

    Nope I don’t believe it. I have had nearly full-length dreams between the 10-minute snooze alarms going off. Sure they were a bit shorter dreams than regular dreams, but they definitely felt longer than ten minutes.

  • Ivan Barrera A.

    As KYousuf1400 says, not only he just proved those people were able to tell which dream was longer… But proved that those people also had limited abilities to describe something , hehehe.
    I have really complicated and full detailed dreams. The most notable i can remember, is the one time i fainted. It was the time it took to be standing to hit the ground, and i was able to describe many hours worth of dream-time.

    It was fun :D

  • Teresaaaa

    I don’t believe it. I passed days in my dream last night?

  • Draco2023

    Me thinks Dement should step away from dream and sleep studies. I will take my own personal experience over his conclusions.

  • Leroy Falconer

    really informative, however while i’m no expert i must still express my disbelief in this study as i think that time in dreams is significantly different in real life. in real life we can measure and quantify based on our 5 senses now just think about it, have you ever had a dream that you completed a day (went to work and came home) only to find out that when you woke you were home already and just fell asleep for a few minutes. i think it all boils down to relativity as time in dreams is also time dilation.

  • Peter Buxton

    I absolutely agree, I say this because I went to bed for a sleep during the afternoon today, I slept for no more than one hour. Except what happened in the dream seemed more like 12 hours, the events that took place, incredible amounts of detail. I completely disagree that a dream hour is the same as real time, utter nonsense. I was woken up by my young daughter and I was convinced that I had slept through the night till the next morning!

Stay Connected

What is RSS? RSS makes it possible to subscribe to a website's updates instead of visiting it by delivering new posts to your RSS reader automatically. Choose to receive some or all of the updates from A Moment of Science:

Support for Indiana Public Media Comes From

About A Moment of Science

Search A Moment of Science