|PSY 101 Variations in Consciousness II: Dreams and Hypnosis|
C. Sleeping (cont'd)
Why do we sleep? We don't know, but.... [Not in book]
1. Energy Conservation & Body Healing (Krueger et al, 2016)
- Sleep leads to lowered calorie use for whole body and, in particular, may restore energy stores in the brain
- May help animals recuperate from disease states
2. Memory Consolidation !!!!
- Long-term memories need to be consolidated
- Unimportant memories need to be thrown away
- Increasing evidence that, without sleep, new memories tend not to be securely stored.
- Payne (2012) reports two phases of consolidation (see diagram)
- During N3/Slow-wave sleep, consolidation of hippocampus-dependent episodic & spatial memories
- During REM sleep: consolidation of procedural & emotional memories
3. Toxic Waste Removal (New, 2013)
- Glymphatic system: Cerebrospinal fluid flows through brain from channels near arteries to veins
- In mice, astrocytes shrink & allow up to 60% more space & 10x flow of CSF than during awake period
- Metabolic waste products (e.g., Amyloid beta proteins) can be cleared from the brain
Some Additional Comments
- Rechtscheffen et al (2002) reproduced an earlier study in which rats died after 2 to 3 weeks after total deprivation of sleep. The reason for this mortality is not clear.
- "Fatal familial insomnia, first described about 30 years ago, is, as the name suggests, a heritable [prion] human disorder that leads first to unremitting insomnia and thence to death" (Stickgold, 2015, p. 54). Because of a genetic mutation of the PRNP gene, misfolded prion proteins amass in the region of the thalamus whose neural cells are eventually destroyed. There are only about 40 families known (with a total of 100 patients) worldwide who carry this genetic disorder. "Average age at onset is 40 yr (ranging from the late 20s to the early 60s). Life expectancy is 7 to 73 mo" (Giambetti, 2015)
The Phenomenon of Dreaming
- Traditionally associated with REM sleep (80-90%). Non-REM dreams have been found less vivid and less story-like than REM dreams.
- Dreams are actually not as bizarre or divorced from everyday life as once thought.
- Themes in dreams include lots of sex, agression, and misfortune.
- Most dreams are relatively self-centered & involve issues that the individual is dealing with at the present time
- Sometimes dreams incorporate external stimuli (e.g., if sprayed with water while asleep, individuals may dream of water falls, rain, baths, etc.)
- Few dreams actually relate to the larger world of current events or public issues
- Children < 9 years old report fewer dreams in REM sleep & different content than adults (blander; less narratively complex). Thus, dreaming may be a developing cognitive skill up through early adolescence.
- 70-90% of schizophrenics with lobotomies stopped dreaming.
- West and East treat dreaming differently: in the East it may be a source of knowledge which is considered more important than in the West.
- Dreams are often examined to see what they predict about the future, what the spirit world or ancestors are thinking, etc.
- Dreams outside the East are often much more vividly remembered than in the West
Content of Dreams (Domhoff, 2001)
From the work of Calvin Hall and others in the middle-late 20th century, the following four (4) themes appear about dream content:
- Males dream twice as often of males as females; females dream equally about males & females
- M & F: aggression > friendliness; misfortune > good fortunes; negative > positive emotions
- Animals: small traditional societies > industrialized societies
- Aggression: M > F
(4) Continuity between concerns of waking life and dream content (Continuity Principle)
Explanations: Why Do We Dream?
Short Answer = We
Actually Don't Know, but....
Freud Cartwright Hobson Domhoff
Wish Fulfillment (Sigmund Freud): Ungratified needs (sexual & aggressive) are expressed symbolically in dreams.
Problem-Solving (Rosalind Cartwright): Creative thinking applied to problems. There is a continuity between awake & dream content.
Activation-Synthesis (J. Allan Hobson): Subcortical area of brain activates for various purposes (perhaps cataloguing or erasing daytime experiences) and brain has to make sense of the activation. Thus, dreams are the ways it accounts for the activation.
No Adaptive Purpose (G. William Domhoff). Since we remember few of our dreams, it is hard to see that there is any adaptive purpose per se for dreaming itself. But, they DO make a kind of sense. "75 to 100 dreams from a person give us a very good psychological portrait of that individual." They reflect something of the individual's underlying personality in a general sort of way.
Franz Anton Mesmer & Mesmerism
- The late 18th century Viennese physician, Franz Mesmer, "borrowed" (stole) an idea from the Jesuit, Fr. Maximillian Hell, who used magnets to "cure" people of illnesses.
- Mesmer argued that there was an interior "animal magnetism" which he could manipulate for the health of people by laying on his hands.
- Actually, Mesmer had discovered the power of suggestion (also called "the placebo effect").
- A Scottish physician, James Braid, later coined the term hypnotism to identify the trance-like state induced in subjects by later followers of Mesmer, the "mesmerists".
F. Mesmer (L) J. Braid (R)
Fr. Maximillian Hell, S.J.
What is hypnosis?
Hypnosis is defined by the American Society of Clinical Hypnosis as "a state of inner absorption, concentration and focused attention."
- Anesthesia (pain relief)
- Sensory distortion & hallucinations
- Disinhibition (see below Myth #1)
- Posthypnotic Suggestion & Amnesia (see below Myth #2)
- Myth #1: Fear that hypnosis will cause a loss of control or a surrender of will to the hypnotist
- Myth #2: Fear that hypnosis will cause a loss of memory or amnesia for what happened during hypnosis. This is true for only a small percentage of subjects and, usually, only if suggested by hypnotist.
What explains hypnosis?
Two rival theories continue to dominate the debate
Role Playing (Nick Spanos, Ted Barber, Ted Sarbin) = Minority view
- Suggestible people fill the role expected of a hypnotized subject
- EEG of hypnotized subject is no different from non-hypnotized
- Many phenomena of hypnosis (e.g., body becomes a "human plank") can be duplicated without hypnosis
- Hypnotized subjects provide incorrect or inaccurate memories in age-regression hypnosis.
Altered State of Consciousness (Ernest "Jack" Hilgard, Martin Orne) = Majority view
- Hypnosis creates a dissociated state of consciousness, i.e., mental processes are split into two separate streams of awareness.
- Consider the everyday experience of "highway hypnosis" -- driving for long distances without any consciousness while thinking about many other issues.
Carey, B. (2009, Nov. 9). A dream interpretation: Tuneups for the brain. New York Times (Online).
Domhoff, G. W. (n.d.). Dreams have psychological meaning and cultural uses, but no known adaptive function. Quantitative Study of Dreams (Adam Schneider & G. William Domhoff), University of California, Santa Cruz. http://www2.ucsc.edu/dreams/Library/purpose.html
Giambetti, P. (2015). Fatal insomnia (Fatal Familial Insomnia). Merck Manual (Professional version). http://www.merckmanuals.com/professional/neurologic-disorders/prion-diseases/fatal-insomnia
Krueger, J. M., Frank, M. G., Wisor, J. P., & Roy, S. (2016). Sleep function: Toward elucidating an enigma. Sleep Medicine Reviews. http://dx.doi.org/10.1016/j.smrv.2015.08.005
Rechtscheffen, A., & Bergman, B. M. (2002). Sleep deprivation in the rat: An update of the 1989 paper. Sleep, 2591), 18-24. Retrieved from www.journalsleep.org/Articles/250104.pdf
Stickgold, R. (2015, October). Sleep on it! Scientific American, 52-57.
This page was originally posted on 11/14/03 and last updated on November 24, 2016