Dreams are hallucinations that occur during certain stages of sleep. They’re strongest during REM sleep, or the rapid eye movement stage, when you may be less likely to recall your dream. Much is known about the role of sleep in regulating our metabolism, blood pressure, brain function, and other aspects of health. But it’s been harder for researchers to explain the role of dreams.

When you’re awake, your thoughts have a certain logic to them. When you sleep, your brain is still active, but your thoughts or dreams often make little or no sense. This may be because the emotional centers of the brain trigger dreams, rather than the logical regions.

Though there’s no definitive proof, dreams are usually autobiographical thoughts based on your recent activities, conversations, or other issues in your life. However, there are some popular theories on the role of dreams.

The role of dreams

Researchers still don’t entirely agree on the purpose of dreams. There are, however, some widely held beliefs and theories.

Dreams as therapists

Your dreams may be ways of confronting emotional dramas in your life. And because your brain is operating at a much more emotional level than when you’re awake, your brain may make connections regarding your feelings that your conscious self wouldn’t make.

Dreams as fight-or-flight training

One of the areas of the brain that’s most active during dreaming is the amygdala. The amygdala is the part of the brain associated with the survival instinct and the fight-or-flight response.

One theory suggests that because the amygdala is more active during sleep than in your waking life, it may be the brain’s way of getting you ready to deal with a threat.

Fortunately, the brainstem sends out nerve signals during REM sleep that relax your muscles. That way you don’t try to run or punch in your sleep.

Dreams as your muse

One theory for why we dream is that it helps facilitate our creative tendencies. Artists of all kinds credit dreams with inspiring some of their most creative work. You may have awakened at times in your life with a great idea for a movie or a song, too.

Without the logic filter you might normally use in your waking life that can restrict your creative flow, your thoughts and ideas have no restrictions when you’re sleeping.

Dreams as memory aides

One widely held theory about the purpose of dreams is that they help you store important memories and things you’ve learned, get rid of unimportant memories, and sort through complicated thoughts and feelings.

Research shows that sleep helps store memories. If you learn new information and sleep on it, you’ll be able to recall it better than if asked to remember that information without the benefit of sleep.

How dreams affect memory storage and recall isn’t clearly understood yet. But dreams may help the brain more efficiently store important information while blocking out stimuli that could interfere with memory and learning.

Why do we have nightmares?

Dreams that help you deal productively with emotions, memories, and other information may seem very helpful. The occasional nightmare is considered a dream that’s simply more frightening or upsetting. Nightmares tend to be caused by stress, anxiety, or sometimes as a reaction to certain medications.

However, if you have nightmares frequently, you could have a sleeping disorder. Regularly occurring scary dreams can be labeled a sleeping disorder if the nightmares:

  • cause you to be anxious about going to sleep
  • lead to frequent disruptions of your sleep
  • bring about other sleeping or psychological problems

Many people experience occasional nightmares throughout their lives. However, the American Sleep Association estimates only about 5 percent of the population experiences persistent nightmares as a sleeping disorder.

What influences dreams?

Some factors that affect us when we’re awake can also influence our dreams.

Health conditions

One of the biggest influences on dreams is how much or how little you’re sleeping. Being sleep-deprived for a night or two (or more) can make parts of your brain much more active when you finally do slip into REM sleep. You’re likely to have more vivid dreams if you’ve had some restless nights. You’re also more likely to recall those dreams, too.

Being pregnant is also a catalyst for vivid dreaming. Increased hormone production affects the way your brain processes thoughts and emotions. This often leads to some intense dreams.

Mental health disorders such as depression and anxiety, as well as bipolar disorder and other mood-related conditions, can trigger intense and sometimes disturbing or negative dreams and nightmares. The medications for these conditions, including antidepressants and antipsychotics, are also associated with a higher risk of nightmares.


There isn’t indisputable evidence that certain foods lead to wilder or better dreams. But it’s clear that some foods may set the stage for you to remember your dreams better.

High-carb foods, for example, can give you quick energy. But after a while, they can leave you feeling down. Anything that affects your waking mood is likely to affect your unconscious mood, too. So, if a sugar crash has you moping around during the day, those feelings could carry over into your sleep.

Also, food that causes you to wake up throughout the night may result in you waking up more frequently in the REM stage. When that happens, you’ll probably remember more of your dreams.

Daily activities

Just as little or interrupted sleep often results in more vivid dreaming, a good night’s sleep will cut down on the intense dreams you’ll recall.

A small study found that one good way to sleep more soundly is to exercise in the morning. A good run or other cardio workout before noon helps set your clock so that you’re more inclined to fall asleep faster and spend more time in deep sleep than if you didn’t exercise or if you exercised late at night.

Runners and other serious fitness enthusiasts tend to spend less time in dreamy REM sleep, which is one of the lightest stages of sleep. Also, the more effectively you can de-stress during the day, the less likely you’ll be to bring stress and anxiety to bed. That should help cut down on nightmares and interrupted sleep each night.

How to remember your dreams

One of the reasons dreams can be difficult to remember is that the brain chemical associated with memory — norepinephrine — and the brain’s electrical activity that helps with recall are at their lowest levels when you’re dreaming. In fact, if you have a dream but don’t wake up during the dream, you won’t be able to remember it. The dreams you remember are the ones that are ongoing when you awaken.

Two ways to help recall your dreams is to tell yourself as you’re falling asleep that you want to remember your dream. If that’s your last thought, you may be more likely to wake up with a dream still somewhat fresh in your memory.

Since dream recall can be easily interrupted by even the slightest distraction, you should try to remember as much of your dream as soon as you wake up. Don’t get out of bed or think about anything else. Try to grasp whatever images or memories you have of your dream and write them down on a pad next to your bed or on your smartphone.