Why do we dream?
Science has made great progress in deepening our understanding of dreaming. Still, there is no clear answer to the question: Why do we dream?
There are, however, a great number of theories being explored. While some scientists argue that dreaming has no direct function, many studying sleep and dreams believe dreaming serves a primary purpose.
What affects how we dream?
There is no simple answer or theory that explains the full role of dreaming in human life. Like sleep, dreams are vulnerable to disruption from problems with mental and physical health. There are a number of conditions that may affect dreams, and that can make dreams more difficult and disturbing. These include depression, anxiety and stress - to name a few.
Drugs and alcohol also can affect dreaming. Alcohol disrupts the normal, healthy sleep cycle and leads to fragmented sleep. Consuming alcohol heavily and too close to bedtime may alter and diminish the time spent in REM sleep. Studies show that alcohol-dependency is linked to dreams with more negative emotional content. Use of and withdrawal from drugs including marijuana and cocaine can also disrupt and reduce REM sleep.
Sleep Disorders
Certain sleep disorders may be accompanied by altered dreaming. Insomnia can heighten dream recall, and also lead to more stressful and disturbing dreams. Depression and anxiety are also more likely in people with insomnia. Obstructive sleep apnea, because of its ability to disrupt normal REM sleep, can cause disturbed dreaming with more bizarre and negative dream content. Narcolepsy, a disorder that involves extreme daytime tiredness and altered sleep-wake cycles, can also lead to more negative and bizarre dreams. Restless Leg Syndrome, a neurological disorder and a sleep disorder, can also be accompanied by nightmares.
REM behavior disorder (RBD) is another condition where the normal paralysis that occurs during REM sleep doesn’t take place. People with REM behavior disorder can move during this sleep phase, and often act out physically in reaction to their dreams. This activity can be violent—thrashing, kicking, getting out of bed—and can lead to injury to the sleeper or a bed partner. We don’t know precisely what causes RBD, but it is associated with neurological illness and injury, as well as to withdrawal from alcohol or narcotics, or use of some anti-depressants.
Typically nightmares and disturbed dreaming are a key indicator of post-traumatic stress disorder (PTSD), as is disrupted sleep. People who suffer from PTSD often experience frequent and recurring nightmares, which may be accompanied by acting out during dreams, with symptoms similar to REM behavior disorder. PTSD occurs in some people who’ve experienced forms of trauma including assault, disaster, war, and combat.
Dreaming and Disease
Altered dreaming is also linked to degenerative neurological conditions, including Parkinson’s disease and some forms of dementia. Violent and aggressive dreams, along with RBD—physically acting out during dreams—are frequent symptoms of neurological degeneration. These dream-related symptoms also have been identified as a strong predictor of the future development of degenerative neurological disease. Studies show that REM behavior disorder (RBD) is a strong predictor for both some types of dementia and Parkinson’s disease.
Dreaming and Waking
What about dreaming’s influence on our waking lives? Dreaming is a universal, enduring aspect of being human (though not limited to humans, since animals dream as well). Dreaming is something we do daily from the time we are very young to very old. Are dreams more than a nightly de-cluttering of the mind? Are there ways that dreams might help us live better? There is a long-held view of dreams as a creative portal—and scientific study may be giving that belief some credence. Evidence suggests that dreams may assist in daytime function and performance, especially as they relate to creativity and problem-solving.
Recent research examined the role of dreams in problem-solving, using a group of lucid dreamers. They found that lucid dreamers could use their dreams effectively to solve creative problems (in the case of the study, the creative problem was crafting a metaphor as directed by researchers). Studies like this one suggest dreams may be fertile territory for influencing and enhancing our waking frame of mind.
More broadly, dreams provide us with insight about what’s preoccupying us, troubling us, engaging our thoughts and emotions. Often healing, often mysterious, always fascinating, dreams can both shape us and show us who we are.
While the jury may still be out on why we sleep, science is showing a connection between our dreams and sleep disorders! Bottomline? Sleep matters.