What Is the Meaning of Dreams?
In 2008 I had a piece about dreams and what they mean in the
Brainpower Newsletter. Although most of the time people are looking
for the meaning of individual dreams or dream types, I reported
on the possible meaning of dreaming in general, from an evolutionary
perspective - based on some recent research. I also included
a few speculations of my own. Since I get repeated requests for
information on dreams and dreaming, I decided to reprint that
newsletter entry here...
What Dreams Mean to an Evolutionary Scientist
The average person will spend six years of his or her life
dreaming. The research seems to indicate that dreaming is necessary
for health. Why? We don't know. What do those dreams mean? We
don't know that either.
Contrary to what some think, there is not yet a theory that
is accepted by the majority of scientists and brain researchers.
In fact, there is not even a universally agreed-upon biological
definition of dreaming. We do know that dreams are strongly associated
with rapid eye movement (REM) during sleep, and that an electroencephalogram
shows brain activity to be more like wakefulness at these times.
Some think dreams are unconscious wishes - which may need
some interpretation to understand. Others say they are the brain
"processing" information from the day, or at least
those things which were not consciously dealt with sufficiently.
They could also be the brain simply "exercising" it's
abilities to think and imagine things.
However, there is a new theory that may fit our experiences
better than the others. Finnish psychologist Antti Revonsuo believes
that dreams are a kind of "survival practice." We create
a kind of virtual reality which simulates emergency situations
and allows us to rehearse responses that may be needed in waking
People faced with real emergencies often report entering a
calm, rapid and automatic response that later seems unreal, as
if it was all a dream. The nighttime threat simulation in dreams,
Revonsuo believes, is why they have this experience. He found
that two thirds of dreams are filled with danger, negative emotions,
monsters, chases, escapes, fights, near-death experiences and
threatening events in general.
You may recall a study I reported on a while back, in which
those who imagined making free-throws with a basketball every
day for a couple weeks improved their performance almost as much
as those who actually practiced. Mental rehearsal appears to
really work, and dreams may be just that: practice. In one study,
rats deprived of dreams - as opposed to those whose sleep was
just interrupted randomly - performed more poorly at simple survival
tasks, like locating a floating platform when they were placed
in a tub of water.
The meaning of dreams, then, according to this theory, is
as a survival tool. They are an important part of our evolutionary
What about those that seem to have no "rehearsal value?"
Perhaps they are somewhat meaningless. After all, even though
hands or eyes or even brains evolved to help us survive, we certainly
can use them for contradictory or irrelevant purposes.
I'll have more on the meaning of our dreams as more research