Psychological theories of dreams
Dreams for testing and selecting mental schemas
Coutts describes dreams as playing a central role in a two-phase sleep process that improves the mind’s ability to meet human needs during wakefulness. During the accommodation phase, mental schemas self-modify by incorporating dream themes. During the emotional selection phase, dreams test prior schema accommodations. Those that appear adaptive are retained, while those that appear maladaptive are culled. The cycle maps to the sleep cycle, repeating several times during a typical night’s sleep. Alfred Adler suggested that dreams are often emotional preparations for solving problems, intoxicating an individual away from common sense toward private logic. The residual dream feelings may either reinforce or inhibit contemplated action.
Evolutionary psychology theories of dreams
Numerous theories state that dreaming is a random by-product of REM sleep physiology and that it does not serve any natural purpose. Flanagan claims that “dreams are evolutionary epiphenomena” and they have no adaptive function in the least. “Dreaming came along as a free ride on a system designed to think and to sleep.” Hobson, for different reasons, also considers dreams epiphenomena. He believes that the substance of dreams have no significant influence on waking actions, and most people go about their daily lives perfectly well without remembering their dreams.
Hobson proposed the activation-synthesis theory, which states that “there is a randomness of dream imagery and the randomness synthesizes dream-generated images to fit the patterns of internally generated stimulations”. This theory is based on the physiology of REM sleep, and Hobson believes dreams are the outcome of the forebrain reacting to random activity beginning at the brainstem. The activation-synthesis theory hypothesizes that the peculiar nature of dreams is attributed to certain parts of the brain trying to piece together a story out of what is essentially bizarre information.
However, evolutionary psychologists believe dreams serve some adaptive function for survival. Deirdre Barrett describes dreaming as simply “thinking in different biochemical state” and believes people continue to work on all the same problems—personal and objective—in that state. Her research finds that anything—math, musical composition, business dilemmas—may get solved during dreaming. In a related theory, which Mark Blechner terms “Oneiric Darwinism,” dreams are seen as creating new ideas through the generation of random thought mutations. Some of these may be rejected by the mind as useless, while others may be seen as valuable and retained.
Finnish psychologist Antti Revonsuo posits that dreams have evolved for “threat simulation” exclusively. According to the Threat Simulation Theory he proposes, during much of human evolution physical and interpersonal threats were serious, giving reproductive advantage to those who survived them. Therefore dreaming evolved to replicate these threats and continually practice dealing with them. In support of this theory, Revonsuo shows that contemporary dreams comprise much more threatening events than people meet in daily non-dream life, and the dreamer usually engages appropriately with them. It is suggested by this theory that dreams serve the purpose of allowing for the rehearsal of threatening scenarios in order to better prepare an individual for real-life threats.
Psychosomatic theory of dreams
Y.D. Tsai developed in 1995 a 3-hypothesis theory that is claimed to provide a mechanism for mind-body interaction and explain many dream-related phenomena, including hypnosis, meridians in Chinese medicine, the increase in heart rate and breathing rate during REM sleep, that babies have longer REM sleep, lucid dreams, etc.
Dreams are a product of “dissociated imagination,” which is dissociated from the conscious self and draws material from sensory memory for simulation, with feedback resulting in hallucination. By simulating the sensory signals to drive the autonomous nerves, dreams can affect mind-body interaction. In the brain and spine, the autonomous “repair nerves,” which can expand the blood vessels, connect with compression and pain nerves. Repair nerves are grouped into many chains called meridians in Chinese medicine. When some repair nerves are prodded by compression or pain to send out their repair signals, a chain reaction spreads out to set other repair nerves in the same meridian into action. While dreaming, the body also employs the meridians to repair the body and help it grow and develop by simulating very intensive movement-compression signals to expand the blood vessels when the level of growth enzymes increase.
Other hypotheses on dreaming
There are many other hypotheses about the function of dreams, including:
- Dreams allow the repressed parts of the mind to be satisfied through fantasy while keeping the conscious mind from thoughts that would suddenly cause one to awaken from shock.
- Freud suggested that bad dreams let the brain learn to gain control over emotions resulting from distressing experiences.
- Jung suggested that dreams may compensate for one-sided attitudes held in waking consciousness.
- Ferenczi proposed that the dream, when told, may communicate something that is not being said outright.
- Dreams regulate mood.
- Hartmann says dreams may function like psychotherapy, by “making connections in a safe place” and allowing the dreamer to integrate thoughts that may be dissociated during waking life.
- More recent research by psychologist Joe Griffin, following a twelve-year review of data from all major sleep laboratories, led to the formulation of the expectation fulfilment theory of dreaming, which suggests that dreaming metaphorically completes patterns of emotional expectation in the autonomic nervous system and lowers stress levels in mammals.
From the 1940s to 1985, Calvin S. Hall collected more than 50,000 dream reports at Western Reserve University. In 1966 Hall and Van De Castle published The Content Analysis of Dreams in which they outlined a coding system to study 1,000 dream reports from college students. It was found that people all over the world dream of mostly the same things. Hall’s complete dream reports became publicly available in the mid-1990s by Hall’s protégé William Domhoff, allowing further different analysis. Personal experiences from the last day or week are frequently incorporated into dreams.
The visual nature of dreams is generally highly phantasmagoric; that is, different locations and objects continuously blend into each other. The visuals (including locations, characters/people, objects/artifacts) are generally reflective of a person’s memories and experiences, but often take on highly exaggerated and bizarre forms.
The Hall data analysis shows that sexual dreams occur no more than 10% of the time and are more prevalent in young to mid-teens. Another study showed that 8% of men’s and women’s dreams have sexual content. In some cases, sexual dreams may result in orgasms or nocturnal emissions. These are colloquially known as wet dreams.
While the content of most dreams is dreamt only once, many people experience recurring dreams—that is, the same dream narrative or dreamscape is experienced over different occasions of sleep.
Color vs. black and white
According to these series of studies, we are irrational about dreams the same way we are irrational in our every day decisions. In their search for meaning, humans can turn to dreams in order to find answers and explanations. The studies find that dreams reflect the human trait of optimistic thinking since the results depict that humans tend to focus more on dreams where good things take place.
Relationship with medical conditions
There is evidence that certain medical conditions (normally only neurological conditions) can impact dreams. For instance, some people with synesthesia have never reported entirely black-and-white dreaming, and often have a difficult time imagining the idea of dreaming in only black and white.