Dream
Dreams are involuntary sequences of images and emotions during sleep.
A dream is a succession of images, dynamic scenes and situations, ideas, emotions, and sensations that usually occur involuntarily in the mind during certain stages of sleep. Humans spend more than two hours dreaming per night, and each dream lasts around 5–20 minutes. The content and function of dreams have been topics of scientific, philosophical and religious interest throughout recorded history.
- field
- Oneirology, psychology, neuroscience
- known_for
- Involuntary mental experiences during sleep, studied across cultures and eras
- key_fact
- Humans spend more than two hours dreaming per night
Lore & Background
Dream interpretation was practiced by the Babylonians in the third millennium BCE and even earlier by the ancient Sumerians. Writings from Mesopotamia and Ancient Egypt describe visitation dreams, where a dream figure, usually a deity or prominent forebear, commands the dreamer to take specific actions. Gudea, king of the Sumerian city-state of Lagash, rebuilt the temple of Ningirsu as the result of such a dream. After antiquity, the passive hearing of visitation dreams gave way to visualized narratives in which the dreamer becomes an active participant. Dreams occur mainly in the rapid-eye movement (REM) stage of sleep, when brain activity is high and resembles that of being awake. However, humans also dream during non-REM sleep, and not all REM awakenings elicit dream reports. To be studied, a dream must first be reduced to a verbal report, which is an account of the subject's memory of the dream, not the dream experience itself. Therefore, dreaming by non-humans is currently unprovable, as is dreaming by human fetuses and pre-verbal infants. From the 1940s to 1985, Calvin S. Results indicated that participants from varying parts of the world demonstrated similarity in their dream content. The most common emotion experienced in dreams was anxiety; negative emotions were much more common than positive ones.
Reader's Guide
Dreams have held scientific, philosophical, and religious significance throughout recorded history, with dream interpretation dating back to the Babylonians and ancient Sumerians. The scientific study of dreams is called oneirology, and most modern study focuses on neurophysiology and hypotheses regarding dream function. However, it is not known where in the brain dreams originate, if there is a single origin, or what the purpose of dreaming is for the body or mind. The human dream experience has undergone sizable shifts over time, from the authoritative visitation dreams of antiquity to the active, narrative dreams of the modern era. The Hall and Van de Castle content analysis system remains influential, showing cross-cultural similarities in dream content. The COVID-19 pandemic influenced dream content, with themes involving fear, illness, and death becoming two to four times more prevalent. Current science cannot specify dream physiology in detail due to research restrictions and the limitations of non-invasive measures. Dreaming by non-humans and pre-verbal humans remains unprovable.
Did You Know?
- Humans spend more than two hours dreaming per night, with each dream lasting around 5–20 minutes.
- Dream interpretation was practiced by the Babylonians in the third millennium BCE and even earlier by the ancient Sumerians.
- The most common emotion experienced in dreams is anxiety; negative emotions are much more common than positive ones.
- People who are blind from birth do not have visual dreams; their dream contents relate to other senses.
Frequently Asked Questions
What is a dream in the context of psychology and neuroscience?
A dream is an involuntary mental experience that unfolds as a sequence of images, scenes, ideas, emotions, and sensations. It typically arises during specific stages of sleep without any conscious effort from the sleeper.
How much time do humans spend dreaming each night?
On average, a person accumulates more than two hours of dream time per night. Individual dream episodes are relatively short, generally lasting somewhere between five and twenty minutes each.
What is the scientific field dedicated to studying dreams?
The discipline is called Oneirology, and it sits at the intersection of psychology and neuroscience. Researchers in this field examine both the content and the functional purpose of dreams across different cultures and historical periods.
Can a person consciously control or choose what they dream about?
No—dreams are classified as involuntary experiences, meaning they occur automatically during certain sleep stages rather than being directed by the sleeper's waking intentions.
Why have dreams been a persistent subject of study across so many fields?
Dreams have attracted scientific, philosophical, and religious inquiry throughout recorded human history because they reveal how the mind organizes memory, emotion, and perception. Their cross-cultural universality makes them a key topic for understanding fundamental aspects of human cognition.
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