Nov. 17, 2025

PSY 101      Class 36: 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 (Recent)

• 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)
  

D. Dreams

The Phenomenon of Dreaming

• Traditionally associated with REM sleep (70-90%). 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, aggression, 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.
• 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:

(1) Changed relatively little in American college students during the 20th century despite broad cultural changes & shifts.

(2) Little change in content once adulthood is reached: older adults dream about the same things as college students do. Confirmed in both cross-sectional and longitudinal (dream journal) research. (Repetition Principle)

(3) Stable cross-cultural similarities & differences

• 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	Revonsuo	Hobson	Domhoff

Wish Fulfillment (Sigmund Freud): Ungratified needs (sexual & aggressive) are expressed symbolically in dreams.

Problem-Solving and Emotional Regulation (Rosalind Cartwright who died in March 2021): The brain never rests and engages in continuous activity over each 24-hour day. Dreams involve creative thinking applied to problems. There is a continuity between awake & dream content, particularly with regard to emotions. As such, dreaming allows the restoration of "emotional balance" by dealing with negative emotional experiences and relating them to previous experiences. As she wrote: "“Dreams are designed to help us maintain our self-identity, our sense of who we are, as our life circumstances change,” Dr. Cartwright wrote in “The Twenty-Four Hour Mind: The Role of Sleep and Dreaming in Our Emotional Lives” (2010). “A bad dream, like an elevated temperature, is a sign that something is wrong.” (quoted in Green, 2021)

Threat Simulation Theory (Evolutionary Psychology; Atti Revonsuo). Noting that unpleasant and fear-provoking dreams are most frequent, Revonsuo & others argue that the "biological function of dreaming is to simulate threatening events, and to rehearse threat perception and threat avoidance" without having actually to endanger oneself (Revonsuo, 2000). [NOT IN BOOK]

Activation-Synthesis (earlier theory by Harvard physiologist, 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.

Protoconsciousness Theory (more recent thesis by J. Allan Hobson who died in July 2021):  Protoconsciousness theory posits “A primordial state of brain organization that is a building block for consciousness” (Hobson 2009). Hobson (2009) suggests that this primordial state of consciousness is prominent prenatally and in infancy when it supports the developing “secondary consciousness” of later childhood and adulthood. Hobson posits further that protoconsciousness then continues throughout life, especially during REM sleep dreaming, functioning in support of waking consciousness" (Pace-Schott, 2014, p. 185).

According to Hobson, "brain activation in sleep allows the development and maintenance of circuits necessary for higher brain functions, including consciousness".  Thus, "REM sleep may constitute a 'protoconscious' state, providing a virtual reality model of the world that is of functional use to the development and maintenance of waking consciousness" (Abstact).

Neurocognitive Theory of Dreaming (G. William Domhoff, 2001, 2019; not in text).  There is an underlying neural substrate for dreaming, i.e., the default mode network (DMN).  Dream abilities develop from early childhood into adulthood (note, BTW, that the DMN itself undergoes maturation during childhood). The cognitive abilities of young children (e.g., to understand and create narratives/stories) undergo development. The content of adult dreams reflect many of the real-life aspects of an individual, e.g., the social networks within which the person functions.

Before developing this theory over the last 20 years, Domhoff argued that there was no significant "adaptive" purpose for dreaming per se since we remember very few of our dreams, yet they are meaningful. However, now that we know about the DMN, dreaming becomes much more closely connected to what we experience in real life. Domhoff has argued that "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.

E. Hypnosis

1810 (link)

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. Animal magnetism was "an invisible natural force (lebensmagnetismus) possessed by all living/animate beings (humans, animals, vegetables, etc.). Mesmer believed that the force could have physical effects, including healing. He tried persistently but without success to achieve scientific recognition of his ideas." {Wikipedia, 20180426}    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". Although Braid based the term on the notion of sleep (hypnos = sleep in Greek), hypnotism is NOT at all related to sleep and, indeed, is sometimes considered the opposite of sleep (see below)    F. Mesmer (L)    J. Braid (R)

Fr. Maximillian Hell, S.J. (link)

What is hypnosis?

Textbook's definition of hypnosis: a systematic procedure that typically produces a heightened state of suggestibility

• Different levels of suggestibility: 10-20% don't respond; 15% respond very well
  

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)

Myths

• 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 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.

References

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

Domhoff, G. W. (2001). A new neurocognitive theory of dreams. Dreaming, 11, 13-33.

Domhoff, G. W. (2019). The neurocognitive theory of dreams at age 20: An assessment and a comparison with four other theories of dreaming. Dreaming, 29(4), 265-302. http://dx.doi.org/10.1037/drm0000119

Giambetti, P. (2015). Fatal insomnia (Fatal Familial Insomnia). Merck Manual (Professional version). http://www.merckmanuals.com/professional/neurologic-disorders/prion-diseases/fatal-insomnia

Green, P. (2021, March 16). Rosalind Cartwright, psychologist and ‘queen of dreams,’ dies at 98 [Obituary]. New York Times. https://www.nytimes.com/2021/03/15/obituaries/rosalind-cartwright-dead.html

Hobson, J. A. (2009). REM sleep and dreaming: towards a theory of protoconsciousness. Nature Reviews Neuroscience, 10, 803-814.

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

Pace-Schott, E. F. (2014) How does protoconsciousness theory mesh with your model of dream emotion?. In N. Tranquillo (Ed.), Dream consciousness. Vienna Circle Institute Library, vol 3. Springer. https://doi.org/10.1007/978-3-319-07296-8_27

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

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

Stickgold, R. (2015, October). Sleep on it! Scientific American, 52-57.

This page was originally posted on 11/14/03