Dreams are one of the most fascinating and mystifying aspects of sleep. Since Sigmund Freud helped draw attention to the potential importance of dreams in the late 19th century, considerable research has worked to unravel both the neuroscience and psychology of dreams.

Despite this advancing scientific knowledge, there is much that remains unknown about both sleep and dreams. Even the most fundamental question — why do we dream at all? While everyone dreams, the content of those dreams and their effect on sleep can vary dramatically from person to person. Dreams are images, thoughts, or feelings that occur during sleep. Visual imagery is the most common , but dreams can involve all of the senses. Some people dream in color while others dream in black and white , and people who are blind tend to have more dream components related to sound, taste, and smell.

Studies have revealed diverse types of dream content, but some typical characteristics of dreaming include:. Although these features are not universal, they are found at least to some extent in most normal dreams. Debate continues among sleep experts about why we dream. Different theories about the purpose of dreaming include:. Experts in the fields of neuroscience and psychology continue to conduct experiments to discover what is happening in the brain during sleep, but even with ongoing research, it may be impossible to conclusively prove any theory for why we dream.

On average, most people dream for around two hours per night. Dreaming can happen during any stage of sleep , but dreams are the most prolific and intense during the rapid eye movement REM stage.

During the REM sleep stage, brain activity ramps up considerably compared to the non-REM stages, which helps explain the distinct types of dreaming during these stages. By contrast, non-REM dreams tend to involve more coherent content that involves thoughts or memories grounded to a specific time and place.

REM sleep is not distributed evenly through the night. The majority of REM sleep happens during the second half of a normal sleep period, which means that dreaming tends to be concentrated in the hours before waking up. How to interpret dreams, and whether they have meaning at all, are matters of considerable controversy. Virtually all experts acknowledge that dreams can involve content that ties back to waking experiences although the content may be changed or misrepresented.

For example, in describing dreams, people often reference people who they recognize clearly even if their appearance is distorted in the dream. The meaning of real-life details appearing in dreams, though, is far from settled.

Dreams can take on many different forms. Lucid dreams occur when a person is in a dream while being actively aware that they are dreaming. Vivid dreams involve especially realistic or clear dream content. Bad dreams are composed of bothersome or distressing content. Recurring dreams involve the same imagery repeating in multiple dreams over time. Even within normal dreams, there are certain types of content that are especially identifiable. Among the most recognizable and common themes in dreams are things like flying, falling, being chased, or being unable to find a bathroom.

This definition is distinct from common usage that may refer to any threatening, scary, or bothersome dream as a nightmare. Dreaming is part of healthy sleep and is generally considered to be completely normal and without any negative effects on sleep.

Nightmares are the exception. Because nightmares involve awakenings, they can become problematic if they occur frequently. Distressing dreams may cause a person to avoid sleep, leading to insufficient sleep. When they do sleep, the prior sleep deprivation can induce a REM sleep rebound that actually worsens nightmares. This negative cycle can cause some people with frequent nightmares to experience insomnia as a chronic sleep problem.

For this reason, people who have nightmares more than once a week, have fragmented sleep, or have daytime sleepiness or changes to their thinking or mood should talk with a doctor. A doctor can review these symptoms to identify the potential causes and treatments of their sleeping problem. For people who want to document or interpret dreams, remembering them is a key first step.

The ability to recall dreams can be different for every person and may vary based on age. Remind yourself that dream recall is a priority. In the lead-up to bedtime, tell yourself that you will remember your dreams, and repeat this mantra before going to sleep.

People with frequent nightmares that disturb sleep should talk with a doctor who can determine if they have nightmare disorder or any other condition affecting their sleep quality. Treatment for nightmare disorder often includes talk therapy that attempts to counteract negative thinking, stress, and anxiety that can worsen nightmares.

Many types of talk therapy attempt to reduce worries or fears, including those that can arise in nightmares. This type of exposure or desensitization therapy helps many patients reframe their emotional reaction to negative imagery since trying to simply suppress negative thoughts may exacerbate nightmares.

Another step in trying to reduce nightmares is to improve sleep hygiene , which includes both sleep-related habits and the bedroom environment. Healthy sleep hygiene can make your nightly sleep more predictable and may help you sleep soundly through the night even if you have bad dreams. Examples of healthy sleep tips include:. Eric Suni has over a decade of experience as a science writer and was previously an information specialist for the National Cancer Institute.

He is board-certified in psychiatry as well as sleep medicine. A nighttime cough is the cold symptom most likely to interfere with sleep. Learn how to sleep with a cough…. Learn more about the causes and underlying mechanisms of REM rebound, a phenomenon in which a person temporarily experiences more….

Several bizarre features of normal dreams have similarities with well-known neuropsychological syndromes that occur after brain damage, such as delusional misidentifications for faces and places. Dreams were evaluated in people experiencing different types of headache. Results showed people with migraine had increased frequency of dreams involving taste and smell. This may suggest that the role of some cerebral structures, such as amygdala and hypothalamus, are involved in migraine mechanisms as well as in the biology of sleep and dreaming.

Music in dreams is rarely studied in scientific literature. However, in a study of 35 professional musicians and 30 non-musicians, the musicians experienced twice as many dreams featuring music, when compared with non-musicians. Musical dream frequency was related to the age of commencement of musical instruction but not to the daily load of musical activity. Nearly half of the recalled music was non-standard, suggesting that original music can be created in dreams.

It has been shown that realistic, localized painful sensations can be experienced in dreams, either through direct incorporation or from memories of pain.

However, the frequency of pain dreams in healthy subjects is low. In one study, 28 non-ventilated burn victims were interviewed for 5 consecutive mornings during their first week of hospitalization. Results showed :. More than half did not report pain dreams. However, these results could suggest that pain dreams occur at a greater frequency in populations currently experiencing pain than in normal volunteers.

One study has linked frontotemporal gamma EEG activity to conscious awareness in dreams. The study found that current stimulation in the lower gamma band during REM sleep influences on-going brain activity and induces self-reflective awareness in dreams. Researchers concluded that higher order consciousness is related to oscillations around 25 and 40 Hz.

Recent research has demonstrated parallels between styles of romantic attachment and general dream content. Assessment results from 61 student participants in committed dating relationships of six months duration or longer revealed a significant association between relationship-specific attachment security and the degree to which dreams about romantic partners followed.

The findings illuminate our understanding of mental representations with regards to specific attachment figures. Researchers compared the dream content of different groups of people in a psychiatric facility. Participants in one group had been admitted after attempting to take their own lives. Their dreams of this group were compared with those of three control groups in the facility who had experienced:. Those who had considered or attempted suicide or carried out violence had were more likely to have dreams with content relating to death and destructive violence.

The right and left hemispheres of the brain seem to contribute in different ways to a dream formation. Researchers of one study concluded that the left hemisphere seems to provide dream origin while the right hemisphere provides dream vividness, figurativeness and affective activation level. A study of adolescents aged 10 to 17 years found that those who were left-handed were more likely to experience lucid dreams and to remember dreams within other dreams.

Studies of brain activity suggest that most people over the age of 10 years dream between 4 and 6 times each night, but some people rarely remember dreaming. It is often said that 5 minutes after a dream, people have forgotten 50 percent of its content, increasing to 90 percent another 5 minutes later. Most dreams are entirely forgotten by the time someone wakes up, but it is not known precisely why dreams are so hard to remember.

There are factors that can potentially influence who remembers their dreams, how much of the dream remains intact, and how vivid it is. Age: Over time, a person is likely to experience changes in sleep timing, structure, and electroencephalographic EEG activity.

Evidence suggests that dream recall progressively decreases from the beginning of adulthood, but not in older age. Dream also become less intense. This evolution occurs faster in men than women, with gender differences in the content of dreams. Gender: A study of dreams experienced by males and females found no differences between the amount of aggression, friendliness, sexuality, male characters, weapons, or clothes that feature in the content.

However, the dreams of females featured a higher number of family members, babies, children, and indoor settings than those of males.

Sleep disorders : Dream recall is heightened in patients with insomnia , and their dreams reflect the stress associated with their condition. The dreams of people with narcolepsy may a more bizarre and negative tone.

One study looked at whether dream recall and dream content would reflect the social relationships of the person who is dreaming. College student volunteers were assessed on measures of attachment, dream recall, dream content, and other psychological measures.

Everyone dreams, although we may not remember our dreams. At different times of life or during different experiencs, our dreams might change. A study investigating anxiety dreams in children aged 9 to 11 years observed the following :. Studies comparing the dreams of pregnant and non-pregnant women showed that:. Those that give care to family or people who have long-term illnesses often have dreams related to that individual.

A study following the dreams of adults that worked for at least a year with individuals at United States hospice centers noted :. It is widely believed that oppressive dreams are frequent in people going through a time of bereavement. A study analyzing dream quality, as well as the linking of oppressive dreams in bereavement, discovered that oppressive dreams:. In another study of people experiencing bereavement:. Younger people are more likely to dream in color.

The number of people aged in their 20s, 30s and 40s dreaming in color increased through to Researchers speculated that color television might play a role in the generational difference. Another study using questionnaires and dream diaries also found older adults had more black and white dreams than the younger participants.

Older people reported that both their color dreams and black and white dreams were equally vivid. However, younger participants said that their black and white dreams were of poorer quality.

Some researchers claim to have evidence that this is possible, but there is not enough evidence to prove it. Most often, this seems to be due to coincidence, a false memory, or the unconscious mind connecting together known information. Dreams may help people learn more about their feelings, beliefs, and values. Images and symbols that appear in dreams will have meanings and connections that are specific to each person.

What causes dreams when we are sleeping? Butler says there are many scientific theories for why we dream: Activation-synthesis theory: Based on the work of Harvard University psychiatrists, this theory suggests dreams occur when there is stimulation in the brain that brings thoughts to our awareness.

You should also see a doctor if you have symptoms of REM behavioral disorder. Share this story. Download the app today! Living Better.

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