We have the idea that time passes slowly in dreams. But is this even true?
Probably not. We have our first hint from the some of the people that first discovered REM sleep. They woke people up 5 or 15 minutes after the start of REM and asked them to guess how long they were dreaming. They were correct 83% of the time. And longer time in REM correlated with longer dreams. These findings have stood the test of time.
We get another clue from a really fantastic study using lucid dreamers. Lucid dreams are dreams in which people are aware that they are dreaming. These lucid dreamers were hooked up to electrodes to monitor their brain activity and eye movements. These lucid dreamers would do simple actions in dreams like counting to 10 or walking 20 steps. They’d signal with their eyes when they started or ended the task. These things took 20-50% longer in a dream than in wake. So if it takes people 24 seconds to count while awake, it took 30 seconds in a dream.
In other words, it looks like time might actually pass faster in a dream than in wake. This is like the opposite of what I would think, so what’s happening?
The authors point to a study which found that time is perceived as going faster when the dreams are complex or bizarre. If I look to my own dreams, I’ll have these jumps. I’ll be on a submarine, then I’ll be in a forest, then I’ll be in a city. I assume a bunch of time has passed since these things would take a long time in waking life.
The other thing is that we dream for a long time. 25% of sleep is REM sleep, which is like 2 hours per night. And you’ll have more REM sleep later in the night with the last REM period lasting up to an hour. And, oh yeah, you don’t just dream in REM sleep, but you dream throughout the night.