Everyone dreams
Even people who say they never dream usually dream several times a night. The difference is in remembering. For a long time dreaming was thought to happen only in REM sleep, the stage when the eyes move quickly under the lids. We now know dreams also occur in other stages, although REM dreams tend to be longer and more vivid.
Where the brain dreams
Researchers in Switzerland and the United States woke volunteers many times during the night and asked whether they had been dreaming, while recording brain activity with high-density EEG. They identified an area at the back of the brain, which they called the posterior hot zone, whose activity indicated whether the person was dreaming, in REM sleep and outside it. The pattern was clear enough to predict, from the signal alone, whether the volunteer would report a dream.
Source: Siclari et al., The neural correlates of dreaming, Nature Neuroscience, 2017.
Does dreaming help learning?
In an experiment published in Current Biology, volunteers trained on a virtual maze task and then took a nap. Those who reported dreaming about the task performed much better on the second attempt than those who did not. For the authors, the dream may be a sign that the brain is reprocessing and strengthening what was just learned.
Why we forget dreams
On waking, a dream fades fast unless it is recorded. If you want to remember more, keep paper by the bed and write everything down in the first minutes, before touching your phone. Waking suddenly in the middle of a dream also raises the chance of recall.
Do dreams have meaning?
There is no scientific basis for dream dictionaries that promise to predict the future. What studies show is that dreams mix recent memories, emotions and worries. Frequent nightmares that disrupt sleep are worth discussing with a health professional.
See also dream meanings and sleep paralysis.
Sources
- Siclari F et al. The neural correlates of dreaming. Nature Neuroscience, 2017. https://doi.org/10.1038/nn.4545
- Wamsley EJ et al. Dreaming of a Learning Task Is Associated with Enhanced Sleep-Dependent Memory Consolidation. Current Biology, 2010. https://doi.org/10.1016/j.cub.2010.03.027
Frequently asked questions
Does everyone dream?
Practically everyone. People who say they do not dream usually just do not remember their dreams.
Do we only dream in REM sleep?
No. Studies show dreams also happen in other sleep stages, though REM dreams tend to be more vivid.
Does dreaming help memory?
One study found that people who dreamed about a task they had just learned performed better afterwards.
How can I remember my dreams?
Write them down as soon as you wake, before picking up your phone. A notebook by the bed helps.
