by Logan Hale

The Cause and Function of Dreams

For this presentation, I researched psychological theories on the cause and function of dream sleep throughout written history from ancient to modern times. I also looked into the neurophysiological aspects of sleep and dreaming.

Abstract

What is a Dream?

- Dream - a series of thoughts, images, or

emotions occurring during sleep and especially

during REM [rapid eye movement] sleep (2010)

- NREM sleep - ~80% of sleep, four stages

leading up to REM sleep, limited dreaming

- REM sleep - ~20% of sleep, several times of

varying length during sleep, neurophysiology

changes drastically, phenomenal dreams occur

“Last night I dreamed I ate a ten-pound marshmallow, and when I woke up the pillow was gone.”Tommy Cooper

What is a Dream?

- Phenomenal Dreams – (p dreams) consciously-

experienced dreams, usually filled with

ambiguous, seemingly unrelated events and

emotions; main focus throughout history

- Lucid Dreams – dreams in which the dreamer is

aware of “being in a dream” and can manipulate

events of the dream

- NREM Dreams – contain basic information

leading up to phenomenal dreams“Dreaming permits each and every one of us to be quietly and safely insane every night of our

lives.”William Dement, in Newsweek, 1959

The Philosophy of Dreams

Ancient Egypt:

- gods could reveal themselves in dreams

- other dreams could be clearly interpreted as

omens (Ex: death = long life; uncovering

butt = parent’s death; sex with mom = loyal

family)

-Chester Beatty papyrus gave knowledge on

Egyptian dream philosophy

“Some men dream of fortunes, others dream of cookies.”Fortune Cookie

(MacKenzie, 1965)

The Philosophy of Dreams

Assyria, Babylonia:

- unlike Egypt, distinction made between

meaningful (true) dreams and meaningless (false)

dreams

- good dreams came from good spirits and

nightmares came from evil spirits

- incubation – dreaming to invoke help from a god

(Epic of Gilgamesh, oldest known dream)

“Dreams that do come true can be as unsettling as those that don't.”Brett Butler, Knee Deep in Paradise

(MacKenzie, 1965)

The Philosophy of Dreams

Bible, Koran:

- Babylonian views on dreams were passed on to

the Jews during their imprisonment in

Babylonia

- monotheism made God the only source of truly

divine dreams; only clear to followers

- Koran took nearly identical views on dreams as

the Jews, but also focused on personality

“Through a dream in a vision by night, when sleep comes over men and they slumber in bed, then He opens the ears of men, and teaching them imparts instruction.”

Job XXXIII:V

(MacKenzie, 1965)

The Philosophy of Dreams

Ancient Greece:

- gods or their messengers would visit in dreams

- according to Homer, “true” dreams came through

a gate of horn, whereas “false” dreams

came through a gate of ivory

- cults of incubation induced dreams for therapeutic

purposes, mainly to cure sterility (dreams

usually included sex with a god/goddess)

“For fleeting dreams have two gates: one is fashioned of horn and one of ivory. Those which pass through the one of sawn ivory are deceptive, bringing tidings which come to nought, but those

which issue from the one of polished horn bring true results when a mortal sees them.”Homer, The Odyssey

(MacKenzie, 1965)

The Philosophyers of Dreams

Heraclitus (535-475 BC):

- first to completely reject divination; dreams were

simply carry-over from waking life

Hippocrates (460-370 BC):

- prodromic dreams- contain symptoms of illness

Plato (428-347 BC):

- dreams are a link to the primitive human soul

“In all of us, even in good men, there is a lawless wild-beast nature, which peers out in sleep.”Plato, The Republic

(MacKenzie, 1965)

The Philosophers of Dreams

Aristotle (384-322 BC):

- slight sense perception during sleep causes unreal

images we interpret as dreams

-dreams can be linked to waking life in three ways:

(1) prodromic dreams can predict illness

(2) waking events can be incorporated into dreams

(3) dream coincidentally similar to a future event

“ by images we conjecture the actions of the future” Synesius of Cyrene

(MacKenzie, 1965)

The Philosophers of Dreams

Artemidorus (between 100 and 200 AD):

- Roman; example of the post-Greek regression to

divination

- Oneirocritica served as guide for Freud and

Jung’s ideas on dream interpretation

- somnium- symbolic; uninterpretable to dreamer

- insomnium- product of everyday life

“Dreams and visions are infused into men for their advantage and instruction.” Artemidorus

(MacKenzie, 1965)

The Philosophers of Dreams

- large hiatus between Rome and Rationalism

Gregory of Nyssa (335-after 394 AD):

- nutritive soul (focused on growth and

reproduction) takes over during dreaming

- dreams express personality (reproductive drive)

St. Thomas Aquinas (1225-1274 AD):

- reassured Christians that not all dreams are divine

“It is the experience of all men that a dream contains some indication of the future. Therefore it is vain to deny that dreams have efficacy in divination.”

St. Thomas Aquinas

(MacKenzie, 1965)

The Pseudoscience of Dreams

-with Rationalism came questions about the validity

of dreams; they were seen as nothing but

evanescent occurrences with no true

meaning

René Descartes (1596-1650 AD):

- random flow of animal spirits (Hergenhahn, 2001)

- sometimes questioned if waking life was a dream

(along with Hobbes, Pascal, and others)

“In a word, as we often dream that we dream, and heap vision upon vision, it may well be that this life itself is but a dream... from which we wake at death...”

Blaise Pascal

The Pseudoscience of Dreams

John Abercrombie (1780-1844 AD):

- first to describe dreams as natural phenomena

which could be scientifically tested (causes

are recent events, external stimuli, and

unconscious memories)

L.F. Alfred Maury (1817-1892 AD):

- showed correlation between external stimuli and

dream imagery (match, perfume, tweezers)

“In dreaming, man reveals himself to himself in all his nakedness and native misery.” Alfred Maury

(MacKenzie, 1965)

The Pseudoscience of Dreams

Sigmund Freud (1856-1939 AD):

- underlying dreams unconsciously build up during

waking life and burst out like a firework

moments before waking

- all speech in dreams comes from memory

- the purpose of all dreams is wish-fulfillment (sex)

- “guardians of sleep”, fulfilling bodily urges

"Obviously one must hold oneself responsible for the evil impulses of one's dreams. In what other way can one deal with them? Unless the content of the dream rightly understood is inspired

by alien spirits, it is part of my own being."Sigmund Freud

(Domhoff, 2003)

The Pseudoscience of Dreams

Freud Debunked:

- only ~50% of dreams contain any recent data

- occur throughout the night, not just upon waking

- speech in dreams is usually a new construction

- wish-fulfillment is only one type (children, PTSD)

- people rarely dream of mundane activities, while

people unable to dream function normally

“The day supplyeth us with truths, the night with fictions and falsehoods...” Sir Thomas Browne

(Domhoff, 2003)

The Pseudoscience of Dreams

Carl Jung (1875-1961 AD):

- dreams are compensatory: expressing parts of the

personality lacking in waking life,

including the archetypes proposed in his theory

of collective unconscious (however, people

dream most often about everyday waking life)

“Let us learn to dream, gentlemen, and then we may perhaps find the truth.” F.A. Kekule

(Domhoff, 2003)

The Function of Dreams

Activation-Synthesis Theory:

- phenomenal dreams are all meaningless

byproducts of the simultaneous functions of

REM sleep (and later, NREM sleep)

- phasic stimulation primarily from the pons causes

seemingly random fluctuations in dream

content and concurrent cognition

(However, it is likely a combination)

“They say dreams are the windows of the soul--take a peek and you can see the inner workings, the nuts and bolts.”

Henry Bromel, Northern Exposure, The Big Kiss, 1991

(Domhoff, 2003)

The Function of Dreams

Problem-Solving Theory:

- dreams are a means of solving problems in

waking life intellectually or psychologically

- evidence for this theory is entirely anecdotal

- research suggests problem-solving comes from

interpretation of dreams, not as a function

of dreams

"A lost but happy dream may shed its light upon our waking hours, and the whole day may be infected with the gloom of a dreary or sorrowful one; yet of neither may we be able to recover a

trace."Walter de la Mare

(Domhoff, 2003)

The Function of Dreams

Threat Perception Theory:

- REM sleep is activated throughout the night

because early humans needed to

periodically check the environment for threats

- phenomenal dreams prepare the dreamer for the

threat upon awakening

Threat Simulation Theory: (self-explanatory)

“Dreaming is not only an organized but also a selective simulation of the world. Not every type of event or activity is simulated by the dream-production mechanisms, no matter how prominent

they may be in our waking lives.” (Revonsuo, 2000)

(Revonsuo, 2000)

The Function of Unrecalled Dreams

Dreaming the memories away:

- dreaming gets rid of useless memories picked up

from recent waking life (lack of efficiency)

Mental-Rehearsal Theory (NREM):

- dreams consolidate and build on procedural

memories

- animal studies (anthropomorphic) and skiing

"Dreaming is an act of pure imagination, attesting in all men a creative power, which, if it were available in waking, would make every man a Dante or Shakespeare."

H. F. Hedge

(Domhoff, 2003)

Logical views on the cause and function of dreams reached a high point in human history with ancient Greece, and then plummeted and stagnated until Rationalism revitalized the interest in dreams. Freud then provided a scientific perspective which, although flawed, instigated a resurgence of new dream theories. There is still too little scientific data to support any one theory on the function of phenomenal dreams, although modern neurophysiology provides insight into their cause.

Conclusion

Coville, Charles (producer). (2009). What are Dreams? [NOVA]. Public Broadcasting System. Streamed from http://www.streamingmadness.net/watch-online/documentary/nova- what-are-dreams-2009/

Dream. (2010). In Merriam-Webster Online. Retrieved from http://www.merriam- webster.com/medical/dream

Domhoff, G.W. (2003). The scientific study of dreams: Neural networks, cognitive development, and content analysis. Washington, DC. American

Psychological Association.

Hergenhahn, B.R. (2001). An introduction to the history of psychology (4th ed.). Belmont, CA. Thomas Learning Inc.

MacKenzie, Norman. (1965). Dreams and dreaming. Toronto, Canada: Copp Clark Publishing Co.

Revonsuo, A. (2000). The reinterpretation of dreams: An evolutionary hypothesis of the function of dreaming. Behavioral and Brain Sciences, 23 (6), 793-1121.

References