Swapna: Dream MeaningsWhy do we dream?
A plain note on what sleep science says about dreaming: sleep cycles, REM sleep, why dreams are forgotten, and what researchers do and do not know.
Everybody dreams, though many do not remember. In a typical night an adult passes through four to six cycles of sleep, each lasting about an hour and a half, and the most vivid dreams happen in the stage called REM (rapid eye movement) sleep, when the brain is as active as when awake but the body is mostly still. REM periods get longer as the night goes on, so the dreams you remember are often those from the early morning.
Why they fade
Most dreams are forgotten within minutes of waking unless you note them down. Remembering is helped by waking slowly, by lying still for a moment and by keeping a notebook by the bed.
What researchers do not know
There are several theories: that dreams help sort memories and feelings, that they are a rehearsal for threats, that they are a by-product of the brain's activity during sleep. Scientists do not agree on any one of them, and there is no scientific evidence that dreams predict the future. Dream books, in India and elsewhere, are a record of culture and belief, not of science.
When to see a doctor
Frequent nightmares, acting out dreams, loud snoring with gasping or day-long tiredness are reasons to talk to a doctor about sleep.
This page reports popular beliefs for interest. Dreams do not predict the future, and nothing here is advice. If a dream is troubling you, talk to someone you trust or to a doctor.