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Verywell / Brianna GilmartinWe spend roughly one-third of our lives sleeping—and during that time, we dream. Many theories exist to explainwhy we dream, but researchers still don’t know for sure. Some believe dreams have symbolic meaning, whereas others believe that they relate to waking life.What scientistsdoknow is that just about everyonedreamsevery time they sleep, and those dreams can be fascinating, exciting, terrifying, or just plain weird.Most of those dreams are forgotten within minutes of waking. Most people dream in color, but some dream in black and white. Our dream content can also differ from one person to the next, and some people can control what they dream about as if they were writing the script. If you’ve ever wondered what makes dreams so fascinating and sometimes strange, exploring some dream facts can help you gain greater insight into thisstate of consciousness.
Verywell / Brianna Gilmartin
We spend roughly one-third of our lives sleeping—and during that time, we dream. Many theories exist to explainwhy we dream, but researchers still don’t know for sure. Some believe dreams have symbolic meaning, whereas others believe that they relate to waking life.
What scientistsdoknow is that just about everyonedreamsevery time they sleep, and those dreams can be fascinating, exciting, terrifying, or just plain weird.
Most of those dreams are forgotten within minutes of waking. Most people dream in color, but some dream in black and white. Our dream content can also differ from one person to the next, and some people can control what they dream about as if they were writing the script. If you’ve ever wondered what makes dreams so fascinating and sometimes strange, exploring some dream facts can help you gain greater insight into thisstate of consciousness.
We Dream Every NightThe brain is active all night long. Brain activity in the forebrain and midbrain is particularly intense duringrapid eye movement (REM) sleep, which is when we dream.Adults and babies alike dream for around two hours per night, even if theydon’t remember it. In fact, researchers have found that people usually have several dreams each night, each typically lasting for five to 20 minutes.During a typical lifetime, people spend an average of six years dreaming.When Dreams Merge With Your Waking Life—What to Know About Deja Reve
We Dream Every Night
The brain is active all night long. Brain activity in the forebrain and midbrain is particularly intense duringrapid eye movement (REM) sleep, which is when we dream.
Adults and babies alike dream for around two hours per night, even if theydon’t remember it. In fact, researchers have found that people usually have several dreams each night, each typically lasting for five to 20 minutes.
During a typical lifetime, people spend an average of six years dreaming.
When Dreams Merge With Your Waking Life—What to Know About Deja Reve
We Forget Most of Our Dreams1:487 Theories on Why We Dream SimplifiedWe forget up to 95% of all dreams shortly after waking.According to one theory about why dreams are so difficult to remember,changes in the brainduring sleep don’t support the information processing and storage needed to form memories.Brain scans of sleepers have shown that the frontal lobes—the area that plays a key role in memory formation—are inactive during REM sleep, the stage in which dreaming occurs.We might also forget our dreams because of changes in the levels of certain neurotransmitters, specificallyacetylcholineandnorepinephrine, during REM sleep.Yet another study found a link between dream recall and the brain matter density of the medial prefrontal cortex (MPFC). Participants with higher white matter density were more likely to recall their dreams.
We Forget Most of Our Dreams
1:487 Theories on Why We Dream Simplified
1:48
7 Theories on Why We Dream Simplified
We forget up to 95% of all dreams shortly after waking.
According to one theory about why dreams are so difficult to remember,changes in the brainduring sleep don’t support the information processing and storage needed to form memories.
Brain scans of sleepers have shown that the frontal lobes—the area that plays a key role in memory formation—are inactive during REM sleep, the stage in which dreaming occurs.
We might also forget our dreams because of changes in the levels of certain neurotransmitters, specificallyacetylcholineandnorepinephrine, during REM sleep.
Yet another study found a link between dream recall and the brain matter density of the medial prefrontal cortex (MPFC). Participants with higher white matter density were more likely to recall their dreams.
Not All Dreams Are in ColorAccording to a 2017 study, around 50% of people report dreaming in color almost all of the time. However, they also suggested they dream in black and white around 10% of the time.An older 2008 study suggested that roughly 12% of people dream only inblack-and-white.People younger than 25 rarely report dreaming in black and white. However, people older than 55 report black-and-white dreams about 25% of the time.Researchers believe this difference results from childhood exposure to black-and-white television. An older study, which found that people in the 1940s rarely reported dreaming in color, supports this idea.
Not All Dreams Are in Color
According to a 2017 study, around 50% of people report dreaming in color almost all of the time. However, they also suggested they dream in black and white around 10% of the time.An older 2008 study suggested that roughly 12% of people dream only inblack-and-white.
People younger than 25 rarely report dreaming in black and white. However, people older than 55 report black-and-white dreams about 25% of the time.Researchers believe this difference results from childhood exposure to black-and-white television. An older study, which found that people in the 1940s rarely reported dreaming in color, supports this idea.
Men and Women Dream DifferentlyResearchers have also found differences between men and women in dream content. In several studies, men reported dreaming about weapons significantly more often than women did, whereas women dreamed about clothing more often than men.Another study showed that men’s dreams tend to have more aggressive content andphysical activity, whereas women’s dreams contain more rejection and exclusion, as well as more conversation than physical activity.Women tend to have slightly longer dreams with more characters. Men dream about other men twice as often as they do about women; women tend to dream about both sexes equally. Women also report having more nightmares than men.
Men and Women Dream Differently
Researchers have also found differences between men and women in dream content. In several studies, men reported dreaming about weapons significantly more often than women did, whereas women dreamed about clothing more often than men.
Another study showed that men’s dreams tend to have more aggressive content andphysical activity, whereas women’s dreams contain more rejection and exclusion, as well as more conversation than physical activity.
Women tend to have slightly longer dreams with more characters. Men dream about other men twice as often as they do about women; women tend to dream about both sexes equally. Women also report having more nightmares than men.
Animals Probably DreamMany think that, when a sleeping dog wags its tail or a sleeping cat swats its paws, it’s dreaming. Although no one can say for sure, researchers believe that most animals go through REM and non-REM sleep stages, so they probably do dream.Animals might not experience dreams in the same way as humans, however. In other words, they might not remember images or attach a storyline to them.
Animals Probably Dream
Many think that, when a sleeping dog wags its tail or a sleeping cat swats its paws, it’s dreaming. Although no one can say for sure, researchers believe that most animals go through REM and non-REM sleep stages, so they probably do dream.
Animals might not experience dreams in the same way as humans, however. In other words, they might not remember images or attach a storyline to them.
You Can Control Your DreamsA lucid dream is one in which you’re aware that you’re dreaming even though you’re still asleep.Lucid dreamingis thought to be a combination of consciousness and REM sleep, during which you can direct or control the dream content.People can learnhow to have lucid dreamsusing various techniques, including mnemonic induction of lucid dreams (MILD) and senses-initiated lucid dreams (SSILD). These involve waking up after five hours and repeating a phrase like “I will remember my dream” or focusing on the stimuli (sights, sounds, sensations) in your sleep environment, respectively.Approximately half of all people can remember at least one instance of lucid dreaming, and some are able to have lucid dreams frequently.
You Can Control Your Dreams
A lucid dream is one in which you’re aware that you’re dreaming even though you’re still asleep.
Lucid dreamingis thought to be a combination of consciousness and REM sleep, during which you can direct or control the dream content.
People can learnhow to have lucid dreamsusing various techniques, including mnemonic induction of lucid dreams (MILD) and senses-initiated lucid dreams (SSILD). These involve waking up after five hours and repeating a phrase like “I will remember my dream” or focusing on the stimuli (sights, sounds, sensations) in your sleep environment, respectively.
Approximately half of all people can remember at least one instance of lucid dreaming, and some are able to have lucid dreams frequently.
Negative Dreams Are More Common
Several factors affect the emotional content of dreams, including anxiety, stress, and certain medications. Research has found that external stimuli, including good and bad smells, can play a role in positive and negative dreams.
The most common emotion experienced in dreams is anxiety. Generally, negative emotions are much more common than positive ones.
How to Interpret Dreams
Blind People May Dream VisuallyIn one study of people who have been blind since birth, they still seemed to experience visual imagery in their dreams, and they had eye movements that correlated to visual dream recall.Although they had fewer eye movements during REM sleep than the sighted participants, the blind participants reported the same dream sensations, including visual content.
Blind People May Dream Visually
In one study of people who have been blind since birth, they still seemed to experience visual imagery in their dreams, and they had eye movements that correlated to visual dream recall.
Although they had fewer eye movements during REM sleep than the sighted participants, the blind participants reported the same dream sensations, including visual content.
You’re Paralyzed While Dreaming
In some cases, this paralysis can even carry over into the waking state for as long as 10 minutes, a condition known as sleep paralysis.
Although the experience can be frightening, it’s perfectly normal and should last only a few minutes before normal muscle control returns.
Some Dreams Are Universal
For example, people from all over the world frequently dream about being chased, being attacked, or falling. Othercommon dream experiencesinclude feeling frozen and unable to move, arriving late, flying, and being naked in public.
How to Know That You Had a Vivid Dream
TakeawaysDreams can range from the fascinating to the anxiety-provoking to the just plain weird. You might wake up scratching your head and wondering “Why did I dream about that? While there’s a lot we still don’t know about dreaming, we have discovered a number of intriguing facts that can provide greater insights into how and why we dream.
Takeaways
Dreams can range from the fascinating to the anxiety-provoking to the just plain weird. You might wake up scratching your head and wondering “Why did I dream about that? While there’s a lot we still don’t know about dreaming, we have discovered a number of intriguing facts that can provide greater insights into how and why we dream.
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Verywell Mind uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read oureditorial processto learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
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