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.