“Why do we dream” is a great mystery question, right within the same league as, “Why do we exist?” …and it can yield just as many different answers depending on the point of view.
There is a lot of diversity of point of view present at conferences for the International Association for the Study of Dreams.
That being said—
We dream for a lot of reasons: physical, mental, emotional, and spiritual. Over time, dreams can help us know ourselves better, and they present opportunities for creativity, growth, health, and wholeness.
Dreams can help us: solve problems, give us creative ideas for our waking lives, allow us to rehearse or practice for future events, learn about our bodies’ physical needs, improve our diets, heal emotional wounds from troubled relationships… they can also help us become more confident, secure, and social… the list goes on!
One of the best features of ordinary dreams is that they can help us get in touch with our feelings—because our rational thinking minds can often get in the way of that in waking life.
There are many different kinds of dreams ranging from ordinary to extraordinary, and some kinds of dreams are sometimes associated with different cycles of sleep.
Studies have shown that everyone dreams. Usually when people say they don’t dream, they just don’t remember having dreamed. On the other hand, some people do have trouble dreaming if they have insomnia and aren’t able to sleep long enough to get to the parts in a sleep cycle that are most favorable for dreaming. Sometimes people build up a huge sleep debt, and then one day they make up for it by sleeping all day! People can experience a whole flood of dreams on days like these.
It was early observations of sleeping infants that led to sleep studies with adults, and the subsequent literature about REM (rapid eye movement) that became the foundation for lab based dream studies. Infants experience REM 50% of the time they sleep, while adults on average experience REM about 22% of the time they sleep.
In an average adult sleep cycle, REM sleep occurs every 90 minutes for 3 – 55 minute periods, with increasing durations later in sleep. It used to be thought that dreams only happened during REM sleep, but now it’s understood other kinds of dreams happen during other sleep cycles as well. During REM sleep, our muscles become temporarily paralyzed so that we don’t act out these dreams with our physical bodies… and our eyes, fingers and toes move rapidly.
We sleep about one third of our lives. Most of the dreams reported in sleep labs have been during REM sleep or generally within 8 minutes on either side of REM sleep—and it adds up to something like two and a half hours of dreaming every night whether we remember it or not… and that only accounts for periods around REM sleep.
Now that we know people may also be dreaming during periods of Non-REM sleep, the time a person spends dreaming—whether ordinary or extraordinary—could be even longer than that.