The six surprise facts about your dreams

WHY do we dream? Do you remember your dreams? Do they say something weird or sinister about you? We've uncovered the secrets behind your dreams.

What are you thinking about right now?

WHY do we dream?

Some say dreams let us fulfil our subconscious fantasies. Others say they help us to hold onto memories, or keep our minds active in preparation for the emotion of the day ahead.

But no one really knows the real function of dreams. Though we do know they're very, very strange.

Here are six fascinating facts about how we dream, rounded up by The Huffington Post.

"Sweet dreams" isn't a thing.

Most of our dreams tend to be bad ones. Our dream experiences are negatively biased, according to a 2008 study.

"The 'default' dream is basically the bad dream," Dr. Ross Levin, a psychologist and sleep disorder specialist at Yeshiva University in New York City, told Reuters.

Some studies argue we've evolved to dream about scary situations more than positive ones so we'll be prepared for survival in case we come across a threat in real life.

Bad dreams can be a "warning sign" of health problems

Just because you have a nightmare doesn't mean something is wrong with you. But a recent study showed that nightmares are sometimes linked to heart conditions and migraines.

And "any infection increases the amount of slow-wave sleep we have," Dr. Patrick McNamara, a neurologist from Boston University Medical School, told the International Business Times.

This "delays the starting point of when we enter dreaming sleep, so dreaming sleep starts late, and can erupt into consciousness", which can lead to vivid dreams and strange hallucinations.

Women have sexy dreams too.

It's not just guys having all the fun. Some 37 per cent of women reported having had a night-time orgasm, according to a 1986 study of university students. While it might be more obvious when men climax during their dreams, women are also having them too.

Dreams paralyse you - but only temporarily

During rapid-eye movement (REM) sleep, our muscles become paralysed - which prevents our bodies from acting out and going for a little sleep walk. Two powerful brain chemical systems work together to paralyse skeletal muscles, so we stay relaxed (and still).

You see more than you hear

Most often our dreams are silent - we see vivid moving images but with no sound.

They're also more auditory than stimulating to the touch, Dr. Robert Stickgold, director of sleep and cognition at Beth Israel Deaconess Medical Center and a Harvard Medical School professor, told The Huffington Post.

###