Why Do We Dream?

A woman floating in the air as she sleeps outside
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When our body snoozes, our brain is busy sorting through the experiences of the day. Key elements of this new information are then added to what we already know about ourselves.

“When you dream, your brain is figuring out an event — looking for the take-home message, while throwing away the little details,” said Robert Stickgold, a cognitive neuroscientist at Harvard Medical School, during a TED Talk.

This helps us solve problems, make sense of our world, find patterns and predict what’s next, Stickgold’s research has found.

“We’re 2½ times more likely to gain insight into a conundrum when we sleep on it. But when we dream about it, we’re 10 times more likely to solve it. Even if the dream doesn’t make sense,” Stickgold says.

Because dreams intensely engage the emotional regions of the brain, it’s no surprise that sexual fantasies occur — as well as nightmares. “Between 8 to 30 percent of adults have a nightmare at least once a month. And women report more frequent and intense nightmares than men,” according to Patrick McNamara, author of Nightmares: The Science and Solution of Those Frightening Visions During Sleep.

Bad days can also bring bad dreams. “If you experience some kind of traumatic event, chances are you will have a nightmare soon after,” McNamara notes.

Depression and anxiety can increase the likelihood of nightmares because they overstimulate areas of the brain, such as the amygdala, which is responsible for fear, worry and panic. So if you’re burdened by upsetting feelings during the day, they can be worse at night when emotions run rampant, one study found.

There are tricks to help us recall, and possibly control, our nocturnal escapades. When you first lie down, your mind races through the events of your day, making a to-do list for the night, Stickgold explains. If you want to focus on something in your dreams, say it out loud three times to try adding it to the list. Don’t drink alcohol before bed: It interferes with REM sleep, the stage when most dreams occur. And try staying in a “dreamlike” state when you wake up. Repeat details of your most recent dream in your mind before opening your eyes. Keep a notebook and pen by your bed to jot down details after waking. And if you’re troubled by consistent nightmares, contact your health care provider.

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This content is provided for informational purposes only and is not intended to provide any expert, professional or specialty advice or recommendations. Readers are urged to consult with their medical providers for all questions.

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