From: toddstark@aol.com (ToddStark)
Newsgroups: alt.hypnosis
Subject: Research FAQ
Date: 15 Feb 1995 15:14:31 -0500
AN OVERVIEW OF THE SCIENTIFIC INVESTIGATION OF HYPNOSIS
(REVISION 8A1)
BY
TODD I. STARK
NOVEMBER 8, 1993 (minor edit on 12/5/94)
---------------------------------------------------
Frequently Asked Questions regarding the scientific
study of hypnosis.
---------------------------------------------------
Written and maintained by Todd I. Stark,
(stark@dwovax.enet.dec.com). July, 1993.
Current email address : ToddStark@AOL.COM
With much appreciation to the following people who
helped by providing references or particularly
useful suggestions :
Grant Fair, for his detailed list of sources on various
physiological correlates of hypnosis, and the idea to
include research on animal hypnosis;
Topher Cooper, for the idea of the eidetic imagery data,
and his invaluable help with the research of psi data;
Jim Lippard, for suggestions about the section on volition
and the section on physiological correlates.
Sidney Markowitz (sidney@apple.com), for his recollection
of the Erickson paper about lip reading and subtle
communication.
Carol Augart Seger (seger@cognet.ucla.edu) for her posting
of various useful references on attention and learning.
Richard E. Cytowic MD (p00907@psilink.com) for his posting
of an excerpt from his new book on synesthesia, which
I quoted in the memory chapter.
Contents
--------
1. What is hypnosis ? How did the various concepts of
hypnosis evolve ?
a. Hypnosis arose out of an operator-assisted
altered state induction model.
b. The cultural origins of the concept of hypnosis
c. The scientific deconstruction of hypnosis
2. What is hypnotic trance ? Does it provide unusual
physical or mental capacities ?
a. 'Trance;' descriptive or misleading ?
b. Are there potential clues in 'trance logic ?'
c. So what is trance logic ?
d. Criticism of trance logic.
e. Trance as distinct from sleep or stupor.
f. 'Trance Reflex' and the appearance of stupor.
g. Evidence of enhanced functioning following suggestion?
(1) 'Mind and Body' in modern medicine.
(2) Hypermnesia, perceptual distortions,
hallucinations, eidetic imagery.
(3) Posthypnotic suggestion and amnesia.
(4) Pain control (analgesia and anesthesia).
(5) Dermatological responses.
(6) Control of bleeding.
(7) Cognition and learning.
(8) Enhanced strength or dexterity.
(9) Immune Response
h. Highly extraordinary experiences while under hypnosis.
(1) Bizarre remembrances under hypnosis
(2) Psychic phenomena under hypnosis
i. Dissociation vs. Suggestibility
(1) Dissociation and Suggestibility :Meaningful traits?
(2) The Effects of Suggestion : Supernatural to mundane
(3) Two "psychosomatic types"
(4) Dissociation versus Situational Factors.
(5) Hypnosis as distinct from Suggestion
(6) Neurobiological basis ?
3. How reliable are things remembered under hypnosis ?
4. Can anyone be hypnotized or only certain people ?
The search for the 'hypnotizability trait.'
a. Hypnotizability
b. The 'Fantasy Prone Personality'
c. Can hypnotizability be modified ?
5. Can I be hypnotized against my will, or forced to do things
I wouldn't ordinarily do ? Hypnosis, volition, and mind
control.
a. Is the hypnotist in control of me ?
b. Voluntary vs. Involuntary
c. Conscious vs. Unconscious
6. What should I read to learn more ? A selected bibliography
on hypnosis and related topics in science and philosophy
of science.
1. What is hypnosis ? Does hypnosis exist ? How and why did the
concept of hypnosis evolve ?
--------------------------------------------------------------
a. Hypnosis arose out of an operator-assisted
altered state induction model.
"In the author's experience there can be developed in a person a
special state of awareness that is termed, for the sake of
convenience and historical considerations, _hypnosis_ or _trance_.
"This state is characterized by the subject's ability to retain the
same capacities possessed in the waking state and to manifest these
capacities in ways possibly, though not neccessarily, dissimiliar
to the usual actions of conscious awareness.
"Trance permits the operator to evoke in a controlled manner
the same mental mechanisms that are operative spontaneously in
everyday life."
The late master clinical hypnotherapist, Milton Erickson
--------------------------------------------------------------
Modern theories of hypnosis have drastically changed the way we
view this subject. Because the most common popular view of
hypnosis is as an altered state of consciousness of some kind
(i.e. trance), this will be used as a departure point to explain
how hypnosis (1) has been viewed since the 18th century when it
was first systematically studied and mass interest first arose,
and (2) has been deconstructed as a unitary concept by some modern
scientific theorists of the subject.
The most popular traditional view of hypnosis is a sleep-like
state induced by a procedure of some kind by an operator and in which
certain special behaviors seem to result; particularly extreme
responsiveness to suggestions made during the hypnotic process,
including physiological responses, and where anomalies of the
experience of volition and memory are consistently reported by
subjects.
Therapeutic interest in hypnosis results mostly from the fact that
response to suggestions apparently includes some increased capacity
to access functions which are normally considered outside of conscious
control and memory. Popular interest in hypnosis stems from the
therapeutic interest, and because of the long associations of
hypnosis with spiritual and secular traditions of self-improvement,
self-insight, or self-fulfillment. There has also been interest
in hypnotic methods in various areas of medical and scientific research.
A truly balanced and comprehensive study of hypnotic phenomena
would probably have to include its relationship with
neuroscience, cognitive science, models of subjective experience,
models of creative thinking processes, theories of psychosocial
development, theories of human language and symbol processing,
and various philosophical stances that are still of interest
today (such as moral and ethical considerations of various
conceptions of the human will and responsibility for actions,
and such as the legal status of testimony revealed with the help of
hypnosis).
Based on a list developed by Zeig in 1988, the following frameworks
can be identified :
1. Janet (and later Hilgard) thought of hypnosis as _dissociation_,
meaning splitting off of aspects of consciousness from each
other in some way, with one seemingly being dominant
at any given time, but others able to influence behavior
at the same time, or to replace the dominant aspect.
This is related to certain theories of how Multiple
Personality Disorder develops. Traditional theories
of spiritualist trances have often involved some notion
of dissociation as well.
2. Sarbin and Coe describe hypnosis in terms of role playing,
acting out the expected role of a hypnotized subject
in response to the relationship with the hypnotist.
Spanos is also a leading proponent of this view.
3. T.X. Barber defined hypnosis in terms of non-hypnotic
behavioral parameters, such as task motivation and
the labelling of a situations as 'hypnotic.'
4. Weitzenhoffer first considered hypnosis a state of enhanced
suggestibility, but later a form of interpersonal influence
via suggestion.
5. Gil and Brenmand described hypnosis in psychoanalytic terms
as regression in service of the ego. Freud, though not
highly important in the history of hypnosis, had great
interest in it initially, and concluded, once he deviated
from Charcot's neurological theories, that it represented
an eroticized dependent relationship between hypnotist and
subject.
6. Edmonston assessed hypnosis as relaxation (based on a Pavlovian
theory of sleep as partial cortical inhibition). This is
linked historically to various physiological theories
of how 'conversion' works in fervent religious activities,
such as that of psychiatrist William Sargant.
7. Spiegel and Spiegel implied that hypnosis was a distinct
biological capacity.
8. Milton Erickson held that hypnosis was a unique, inner-directed
altered state of functioning.
9. Various followers of Erickson's lead have proposed that hypnosis
is best defined subjectively and phenomenologically
as a process between individuals, and a communications
strategy for the achievement of therapeutic goals, with
or without recourse to 'trance.'
10. We should also reserve at least one category for the numerous
esoteric, non-scientific, or archaic models which view
hypnosis in general as a condition of subtle unidentified or
unobservable bodily fluids, a unique electromagnetic
field phenomenon, or the result of supernatural
influences or contacts, or contact with alternate
realms of existence (in a non-metaphorical sense).
B. The cultural origins of the concept of hypnosis
The creation of a distinct concept of _hypnosis_ owes its
existence mostly to a charismatic 18th century healer named
Franz Anton Mesmer (1734-1815).
Mesmer had a deep interest in Paracelsan astrological principles,
and the supposed direct influence of heavenly bodies on human
health, by means of what were believed by Mesmer and others
to be measureable physical forces (as opposed to the
subtle forces of later occult doctrines interpreting
Mesmerism).
Mesmer first applied magnets to patient's bodies in elaborate
theatrical rituals that often resulted in expected spasmodic
muscular contractions and collapse, and often the cure of various
kinds of illness. Mesmer favored the rationalist views of his
time, taking on terms like _gravitation_ and _magnetism_ to
originally describe his theories of his healing work, and how
the subtle fluids within the body could be influenced by him.
Mesmerism caught on widely, attracting followers to many
spiritualist, religious, and scientific variations of mesmerism,
as well as to 'mesmerism' as a dramatic form of entertainment
for its own sake ('stage hypnosis').
It was highly influential in a number of popular movements,
some of which are still very popular today.
The clearest transition between Mesmer's _animal_magnetism_
and modern therapeutic hypnosis was represented by Manchester
surgeon James Braid, who coined the term _hypnosis_ (from
previous use by French researchers) in 1843. The term
refers to Hypnos, the Greek god of sleep, because most forms
of mesmerism at that time involved the production of an apparently
sleep-like condition.
Braid, as many scientists and physicians before and after him,
recognized in hypnosis certain legitimate psychological phenomena
of interest, but requiring much more systematic investigation
to understand. Mesmer had come to believe that it was not
physical forces via magnets but he himself that was producing
the cures he produced. Others not long after Mesmer soon began
to suspect that the human imagination played a much larger role
in the process than did any physical forces or capacities of the
mesmerist. This was important, because mesmerism went through
a number of periods of great disrepute due to associations with
occultism and various kinds of blatant charlatanism.
A split arose between those interested in hypnosis as a subject
of scientific investigation and as an adjunct to medical
treatment, and those who considered it a tool for personal
or spiritual fulfillment, or for esoteric investigations
of religious or 'magical' nature. Faith healing, mind cure,
and Christian Science were all heavily influenced by hypnosis,
and derived much of their impetus in the late 19th century
from the reputation of Mesmer and later mesmerists. Various
followers of the highly influential Theosophical Society and
of the Hermetic Order of the Golden Dawn magical fraternity
found great affinity for the magnetic theories of mesmerism,
which they often interpreted in a semi-metaphorical way
rather than as literal electromagnetism.
In the early scientific study, Braid at first thought that
hypnotic induction would yield a unique condition of the
nervous system that was linked somehow to certain cures by
suggestion. He later rejected this, and other physiological
explanations of hypnosis, and emphasized "mental" factors
almost exclusively. The theory of neural inhibition has never
been completely rejected as applicable, however, though often
considered insufficient by itself. Ivan Pavlov later greatly
expanded on the neural inhibition theory in his concept of
the physiology of sleep (as a progressive cortical inhibition,
which turns out to be fairly accurate - in general if not in
detail).
This neurological explanation of hypnosis was strongly rejected by
Charcot, who believed that the best hypnotic subjects were
'hysterics,' and that hypnosis was therefore a manifestation
of what was then considered the mental illness of hysteria.
His belief turned out to be wrong, and his view of hysteria
as a distinct mental illness as well, and his psychopathological
view was rejected by the end of the 19th century. Two
legacies of the neurological pathological theories of Charcot and the
so-called "Paris school" of hypnosis that have endured are
cortical inhibition theory and the later development
of dissociation theory, though neither one serves as a complete
theory of hypnosis on its own.
In the early 20th century, the foundation for most hypnotic
theory was laid by the members of the so-called "Nancy school"
of hypnosis (such as Liebeault and Bernheim) who elaborated
a theory of hypnotic _suggestion_ based on ideomotor action.
This theory had eventually replaced not only the early
neuropathological view, but also Braid's early psychological
theory, "monoideism," the theory that unconflicted ideas
automatically lead to actions. Ideomotor action theory says
that ideas suggested by the hypnotist lead automatically
to actions, which are then experienced by the subject as
unwilled. Ideomotor action is another example of a useful
but incomplete model of hypnotic responding. The Nancy school was
perhaps most notable in their deemphasis of hypnotic ritual
and their strong emphasis on _suggestion_ as a mundane though
useful psychological process.
Sigmund Freud had originally studied under Charcot and had a
deep interest in hypnosis for much of his life. In 1889, he
shifted from Charcot's view to that of the Nancy school's
emphasis on suggestion rather than hysteria, believing that patients
often remembered repressed memories in a beneficial process under
hypnosis. Freud was reportedly a very poor hypnotist, being
limited to a simple authoritarian style of induction, and in
1896, he rejected hypnotic induction ritual as unneccessary
and too likely to foster unwanted amorous advances by patients
('transference,' and the theory of hypnosis as an eroticized
dependent relationship). Freud replaced the hypnotic procedure
with simply placing his hand on the subject's forehead to
help establish what he believed was the proper social relationship
of doctor in dominance over patient.
What qualified acceptance of hypnosis in medicine that we have
today is largely due to the efforts of pioneers in the experimental
study of hypnosis, starting in the 1920's and 30's. Foremost
early researchers were Clark Hull and his then student,
Milton Erickson. Hull's 1933 discussion of scientific research
into hypnosis (Hypnosis_and_Suggestibility) is still considered a
classic.
Erickson later came to disagree with Hull on the important issue
of fundamental approach, stressing the complex subjective
inner processes operating in hypnosis, rather than the measureable
correlates and standardized procedures promoted by Hull. Hull
went on to make important contributions in learning theory, while
Erickson went on to become the name most closely associated with
clinical hypnosis today.
Milton Erickson died in 1980, but left
a legacy of often zealous followers, a number of important contributions
to the field, and several offshoot schools of applied psychology
based on his core principles of indirect strategic therapy and
suggestion, and based on hypothetical unconscious processes and
indirect forms of human communication. Examples include
Jay Haley's strategic model of therapy, the MRI Interactional
model, the Erickson-Rossi hypnotic theories, Neurolinguistic
Programming (NLP), and a number of later frameworks such as
that of Lankton (1983) and Gilligan (1987). The 'Ericksonian' models
deliberately blur the traditional distinction between hypnosis
and other forms of therapy, and share this basic idea with the
'skeptical' view of hypnosis, which we will consider in the
next section.
In addition to Erickson and Hull, modern scientific research into
hypnosis is often associated with a period of intense experimental
research in the late 1950's and early 1960's by notables such as
J.P Sutcliffe, T.X. Barber, M.T. Orne, E.R. Hilgard, R.E. Shor,
and T.R. Sarbin. The work of these researchers had been
particularly influential on the current scientific view of
hypnosis, especially as viewed in medicine.
C. The scientific deconstruction of hypnosis
The 'skeptical' modern conception of hypnosis was pioneered
by Theodore Sarbin in 1950, as a social-psychological
_alternative_ to the views that (1) a single distinctive
neurological and psychological state underlies all hypnotic
phenomena (Paris school), and (2) that suggestions somehow mechanically
produce responses without the participation of the subject
(Nancy school).
Sarbin instead saw hypnosis as a social encounter, in which
the hypnotist and subject play out pre-determined roles.
Sarbin's role theory was influenced by R.W. White, who in his
"A Preface to a Theory of Hypnotism," in _The_Journal_of_Abnormal_
and_Social_Psychology in 1941 discussed various serious limitations
of both the ideomotor action and dissociation theories. He pointed
out that the responses of hypnotic subjects are too complex to
consider them as automatic results of suggestions, that subjects
often creatively and actively improvise a performance based
on their interpretation of suggestions. Thus for just about the
first time posing hypnotic behavior as _creative_ and
_goal_directed_, rather than mechanical.
In addition to the use of social role theory to replace
mechanistic theories of hypnotic response, 'skeptical' theories
of hypnosis often refer to empirical research to illustrate
that hypnotic subjects do not in fact transcend the
behavioral capabilities of non-hypnotic subjects. The empirical
objective approach to hypnosis, effectively introduced to
the study of hypnosis by Clark Hull in the 1930's, involves
an implicit mistrust of verbal reports of subjective experience,
and the use of quantifiable response indicies.
Key questions remaining in the modern study of hypnosis
within active role theory and other non-special-state frameworks
include : (1) whether a hypnotic procedure is neccessary (first
studied by T.X. Barber in the late 1960's and in the 1970's); (2) in
what specific ways active cognitive functioning might be altered in
hypnotic contexts (studied by Orne and by Shor starting in the late
1950's), and (3) the degree to which _dissociation_ of aspects
of consciousness actually occurs in each of the various
hypnotic phenomena (Janet, Prince, later E.R. Hilgard).
All this leads to the crucial theoretical distinction of whether
it is meaningful and useful to postulate such a thing as
unconscious goal directed activity, and the global psychological
questions of what exactly are the nature of volition, compliance,
belief, and imagination.
Graham Wagstaff of the University of Liverpool expresses the
non-special-state view of hypnosis :
"... studies of hypnosis have drawn our attention to a number of
mundane yet fascinating phenomena that do beg for explanations,
even though, as I have pointed out, a theory of hypnosis per se
doesn't need to provide such explanations.
"For example, we need to know how a placebo works; how
suggestions can affect dermatological responses; how imagination
can produce the experience of a dry mouth, an itch, or nausea;
how coping strategies can affect the experience of pain; and so on.
"However, I would consider these phenomena to be best investigated
without any reference to 'hypnosis' because placing them in
a context called 'hypnosis' probably serves only to confound them
with extra demand characteristics."
At another point, Wagstaff acknowledges the practical consideration :
"... for some patients there may actually be unique advantages to
defining a context as 'hypnosis,' for example, 'hypnotic amnesia,'
if only pretended is a potentially useful device not only for
saving face but also for providing a legitimate context for
controlling the vivid remembering of traumatic experience."
---------------------------------
2. What is a hypnotic 'trance' ?
---------------------------------
a. 'Trance;' descriptive or misleading ?
-----------------------------------------
Most of the classical notions of hypnosis have long held that hypnosis
was special in some way from other types of interpersonal
communication *and* that an _induction_ (preparatory process
considered by some to be neccessary in the production of hypnotic
phenomena) would lead to a state in which the subject's awareness
and behavioral responding was somehow altered from the usual.
The name historically most commonly associated with this altered state
of functioning is 'trance,' a term shared by the description of the
activities of certain spiritualist mediums and other phenomena
that some psychologists might refer to as 'dissociative,' because
something about the individual's personality appears split off from
the usual response patterns to the environment.
Trance, for reasons we shall examine here, can be a very misleading
term for what is going on in hypnosis, since it is not neccessarily
a sleep or stupor as some of traditional connotations of the term
trance imply.
But 'trance' is so ubiquitous in literature that it might serve us to
be familiar with its uses and the issues underlying it, and to use it
as a starting point.
There were a great many experimental and clinical studies done
to try to determine what might be unique about hypnosis, as
opposed to other kinds of situations (e.g. people simply
being motivated to comply with the hypnotist; i.e. hypnotic
simulators). Outward behavioral signs and virtually every
physiological measurement reported in hypnosis differ seemingly
not at all from the usual waking state of consciousness, as the
non-state theorists contend.
Years of careful analysis by a number of researchers were mostly
fruitless in turning up any reliable physiological correlates of
hypnosis that were not (1) related to the relaxation associated
with the induction (most inductions, but not all, involve physical
relaxation); or (2) an obvious result of a suggestion rather than the
mechanism responsible for the observed _suggestibility_ assumed to
some degree unique to hypnotic trance.
At least one theory of hypnosis considers it equivalent to
a form of relaxation. Comparison of various relaxation methods with
regard to both objective measurements and subjective reports indicate
deep relaxation accompanying some hypnosis but not all hypnosis.
Hypnotic suggestibility is apparently not limited to relaxed
states. This fact is answered by hypnosis_as_relaxation theorists
by saying that there is such a thing as "cognitive relaxation"
(mental relaxation processes not accompanied by muscular relaxation)
which is distinct from "somatic (muscular) relaxation," and can be
found separately though deepest relaxation probably involves both.
In Morse, Martin, Furst, & Dubin, "A physiological and
subjective evaluation of meditation, hypnosis, and relaxation,"
from Journal Psychosomatic Medicine. 39(5):304-24, 1977 Sep-Oct,
a representative study of relaxation was done.
Subjects were monitored for respiratory rate, pulse rate, blood
pressure, skin resistance, EEG activity, and muscle activity. They were
monitored during the alert state, meditation (TM or simple word type),
hypnosis (relaxation and task types), and relaxation. Ss gave a verbal
comparative evaluation of each state. The results showed significantly
better relaxation responses for the relaxation states (relaxation,
relaxation- hypnosis, meditation) than for the alert state. There were
no significant differences between the relaxation states except for the
measure "muscle activity" in which meditation was significantly better
than the other relaxation states. Overall, there were significant
differences between task-hypnosis and relaxation-hypnosis. No
significant differences were found between TM and simple word
meditation. For the subjective measures, relaxation-hypnosis and
meditation were significantly better than relaxation, but no significant
differences were found between meditation and relaxation-hypnosis.
There are a few more recent attempts to find physiological correlates
of hypnotic suggestibility. One of these was EEG research by David
Spiegel of Stanford, published in the _Journal_of_Abnormal_Psychology_,
94:249-255, by Spiegel, Cutcomb, Ren, and Pribram, (1985) "Hypnotic
Hallucination Alters Evoked Potentials." Spiegel seemed to find
an evoked response pattern that appeared during hypnotically suggested
hallucination yet not during simulation of hypnotic hallucination.
Nicholas Spanos and others have argued that this EEG data has been
misinterpreted given the nature of the control subjects used.
(Author's response to commentary by Spiegel, of Spanos, N. (1986)
"Hypnotic Behavior: A Social-Psychological Interpretation of Amnesia,
Analgesia, and 'Trance Logic'." _Behavioral and Brain Sciences_
9:449-502).
In another similar attempt, from 1976, but measuring certain frequencies
of EEG activity rather than evoked potentials, a Russian journal
reports some tentative success at finding a physiological correlate
to hypnotic induction. See Aladzhalova, Rozhnov, &
Kamenetskii, "Human hypnosis and super-slow electrical activity of the
brain." [RUSSIAN] Zhurnal Nevropatologii I Psikhiatrii Imeni S - S -
Korsakova. 76(5):704- 9, 1976.
In the above article, the authors studied the transformation of
infraslow oscillations of brain potentials in 15 patients with
neuroses during 50 sessions of hypnosis. The results of such studies
permitted to distinguish some important traits in the changes of
infraslow oscillations of brain potentials in different stages
of hypnosis. It is concluded that a study of these changes during
hypnosis may establish some correlations between the physiological
state of the brain and the unconscious mental processes.
b. Are there potential clues in 'trance logic ?'
------------------------------------------------
One particular researcher, psychiatrist M.T. Orne of the
University of Pennsylvania, finally concluded that objective
correlates were not to be found in the available physiological
measurements of the time, and that they were apparently of no value in
determining whether a hypnotized subject was 'truly hypnotized' or
'simulating hypnosis.'
Orne, who did recognize from both highly consistent verbal reports
of hypnotized subjects and from various clinical and empirical studies
that there was indeed _something_ unique about hypnosis in at least
_some_ subjects, concluded that that he would have to use verbal
reports of subjective experience rather than rely on measurements.
He carried out a series of clever experiments which seemed to
establish a reliable way of distinguishing simulators from hypnotized
subjects by their verbal reports. The resulting alteration of mental
function was found to be present in nearly all deeply hypnotized
subjects, and almost never found to the same degree in people
who were not hypnotized but were motivated to simulate hypnotic
phenomena.
The most obvious aspects of this alteration of function were
dubbed 'trance logic,' and appeared to correlate well with the
anecdotal reports of the clinicians like Milton Erickson who had
long considered verbal reports of hypnotized subjects to be
valuable in distinguishing what was going on in hypnosis.
c. What is Trance Logic ?
--------------------------
Trance logic refers to a set of characteristics of mental
functioning that are specifically found in 'deep trance'
phenomena of hypnosis, as opposed to 'light trance,' which has not
even reliable subjective correlates and cannot really be distinguished
from simulation experimentally. These characteristics involve
particularly an alteration in language processing. Words, in trance
logic, are interpreted much more literally, communication being
conveyed by focusing on words themselves rather than ideas. There is
also an associated decrease in critical judgement of language being
processed, and an increased tolerance for incongruity.
It is in some ways as if the subject were like a small child with very
limited experience to use in interpreting ideas conveyed by the
hypnotist. There also is a shift toward what psychoanalysts call
'primary process' thinking, or thinking in terms of images and symbols
more than words; an increased availability of affect;
and other characteristics that simulators do not consistently reproduce.
This consistent set of characteristics of deep trance has been
one of the influences leading to several kinds of theories of what
trance actually involves :
1. Partly because language skills are 'child-like,' and
meaningful long forgotten childhood memories can
apparently sometimes be vividly re-experienced
(see the later section on the reliability of
recall in hypnosis) the theory that trance generally
represents some kind of psychological regression to an
earlier developmental stage has long been popular in
some circles.
2. Partly because the individual appears to become
disconnected somehow with the usual context they use
to evaluate ideas, a cognitive dissociation theory
arose. (Also partly because of anomalies involving
apparent multiple simultaneous 'intentions.')
3. Partly because the cues prompting the subject's
behavior become more internal and progressively more
obscure to an outside observer, trance has been
viewed as 'contact with the unconscious mind.'
4. Largely because some of the characteristics of trance
logic correlate well with some of those discovered
to be specialized in many people in the non-dominant
cerebral hemisphere, there is also a popular theory
that deep trance involves a somehow selective use of one
hemisphere of the brain, or in the most simplified
version of this theory, a 'putting to sleep'
somehow of the dominant (language specialized)
hemisphere. Some brain scientists strongly
disagree with this view, emphasizing the
complex interdependence of the brain hemispheres
even in typical hypnotic-type situations.
d. Critique of Trance Logic
---------------------------
The notion of trance logic, rooted as it is in subjective reports,
has been questioned by some of the non-state theorists, such as
Nicholas Spanos, who do not believe that trance logic represents
any sort of defining characteristic of hypnotic responding.
Examples of critiques of this concept can be found in
Nicholas Spanos, "Hypnotic behavior: A social-psychological
interpretation of amnesia, analgesia, and 'trance logic,'"
_Behavioral and Brain Sciences_ 9(1986):449-502, and a paper
cited by Spanos in the above; Nicholas P. Spanos, H.P. de Groot,
D.K. Tiller, J.R. Weekes, and L.D. Bertrand, "'Trance logic' duality
and hidden observer responding in hypnotic, imagination control, and
simulating subjects," _Journal of Abnormal Psychology_
94(1985):611-623.
e. Trance as distinct from sleep or stupor
------------------------------------------
I think we can fairly conclude from the research on hypnosis
done so far that 'trance' may in fact have useful meaning for
describing the subjective experience of subjects in hypnotic
situations, but is not explained, or even described, by any one
simple theory yet proposed, either neurological or psychological.
All of the current theories seem to leave aspects unexplained.
Clearly, selective cerebral inhibition and activation of _some_kind_
is involved at various stages of a hypnotic induction, but not yet
in any way we can uniquely distinguish from other forms of waking
response to changing stimulii in other situations. And certainly
hypnotic response does not rely upon the generallized
inhibition found in the action of depressant drugs or in the normal
sleep state. It is a much more highly specific effect, if indeed
it truly is distinct in some way, as subjective data appear to
suggest.
The most common neurological theories of hypnosis over the years
as a form of partial sleep have mostly been based on (1) the
superficial resemblance of a classically induced subject to a
near-sleeping person, (2) on the ease with which a deeply hypnotized
subject will fall off to sleep on suggestion or if hypnosis is not
explicitly ended, and (3) because various drugs that induce sleep-like
or stuporous states can produce some of the same characteristics as
hypnotic trance.
It has been very consistently determined that trance
itself has nothing at all to do with sleep, and is much more
easily distinguished from a sleeping state physiologically than
from a waking state. Measurements attempted included
a number of famous early experimental studies in the 1930's,
on such variables as EEG measurements, cerebral circulation, heart
rate, respiration, basal metabolism, and various behavioral parameters.
Representative of these experiments comparing hypnosis and sleep
was :
M.J. Bass, "Differentiation of the hypnotic trance
from normal sleep," Journal_of_Experimental_Psychology,
1931, 14:382-399.
Though the mentation in hypnosis often resembles dreaming,
it appears much closer to _daydreaming_ in character than to normal
night time dreaming.
Clark Hull, in his 1936 classic Hypnosis_and_Sugestibility
describes a number of experimental setups for distinguishing
the _mental_ characteristics of sleep from those of hypnotic
trance.
One thing suggested by this is that if sleep can be viewed as largely
a generallized cortical inhibition, and trance is not in any
determinable way identified with sleep, that trance is NOT a
form of sleep or a stupor. This is also easily determined by
observing the range of activities possible in hypnotized subjects
(compared to waking subjects and those under the influence of
depressant drugs).
f. 'Trance Reflex' and the appearance of stupor
------------------------------------------------
So the question remains, if trance is not sleep or stupor, then
why do hypnotized subjects commonly appear so passive ?
The consensus on this subject, from studies of 'waking hypnosis,'
('trance' in which the subject acts normally and does not show
any evidence of the classical relaxed deep trance state), and from
many years of clinical observations, is that the apparent
lethargy and catalepsy are more a result of suggestions used
to deepen hypnosis than a neccessary correlate of suggestibility
or trance itself in general. In a way, a side-effect of trance
rather than a quality or cause of trance. There is also seemingly a
temporary but distinct immobilizing reflex following certain kinds of
stimuli used in some hypnotic inductions. This may help provide
a temporary or initial facilitation of hypnotic suggestibility in some
people, according to some theories.
Monotonous visual stimuli, surprise, fear, physical restraint, and a
number of other factors have long been observed to produce 'trance'
with fixation (followed by defocusing) of gaze, narrowing or
attenuation of externally focused attention, general immobility, and
various physiological changes which resemble the correlates of
relaxation and _internally_directed_ (visual) attention in humans.
Perhaps the most routine observance of this is with people gazing
into television sets or in the familiar case of 'highway hypnosis.'
It appears that this type of 'trance' induction often precedes
the production of hypnotic suggestion phenomena, and can occur
prior to any verbal suggestions, from proprioceptive or visual
stimuli alone. It is probably closest to the traditional view
of the hypnotist swinging a watch to put their subjects 'to sleep.'
One means of searching for the basis for this seemingly reflexive
trance response is from phylogenetic data, using animals. A similar
response occurs in monkeys and other animals under both laboratory
and natural conditions, as an apparent passive defensive
response (resembling death) under certain extreme conditions.
Various Russian researchers investigating animal hypnosis
seem to have discovered electroencephalographic correlates
of this animal 'death trance' which resembles the initial
trance/inhibition effect that sometimes precedes human hypnotic
suggestibility. They report an interhemispheric asymmetry of the
brain, which a recent Russian email journal article, (Petrova E.V.,
Shlyk G.G., Kuznetsova G.D., Shirvinska M.A., Pirozhenko A.V.,
HYPNOSIS IN MACACA RHESUS IS CHARACTERIZED BY DIFFERENT
PHASES AND INTERHEMISPHERIC EEG ASYMMETRY), summarizes as being
"created as the result of the activation of the right hemisphere."
They cite :
Simonov P.V. The Motivation Brain, Gordon a. Breach Pub.,
N.Y.-L., 1992.
Kuznetsova G.D., Nezlina N. I., Petrova E.V. Dokl. Akad.
Nauk, 1988, 302:623.
Petrova E.V., Luchkova T.I.,Kuznetsova G.D. Zh. Vyssh. Nerv.
Deyat. 1992, 42: 129.
As evidence of a correlation between right hemisphere cortical activity
and human hypnosis, they cite :
Gruzeiler J., Brow T., Perry A. et al. Int. J. Psychophysiol.,
1984, 2:131.
Meszaros J., Growford H.J., Nady-Kovacs A, Szabo Cs.,
Neuroscience, 1987, Suppl. 22:472.
One investigation into the relationship of primate behavior and
electrical activity of the brain (EEG) involved 45 male Macaca Rhesus
monkeys seated in a primatologic chair and observing the oscillation
of a shining ball, 4 cm in diameter, placed 15 cm in front the
animal's eyes for 15-20 minutes.
In this experiment, six of the monkeys immediately
stopped motor activity. At first their eyes were fixed on the ball,
then muscle tonus weakened, eyes became unfocused, and respiration
slowed. These same symptoms appeared in the remaining animals, although
they developed slower. During the first 2-3 minutes of the stimulation,
the slower responding monkeys showed a negative reaction to the ball
(a monkey abruptly turned away or tried to push it away). Then the
negativism ceased and the first signs of inhibition appeared: yawning,
scratching, and obtrusive hand motions.
Finally, what the experimenters call the 'hypnotic state' ensued; eyes
fixed on the ball, the animal became calm, and closed its eyes. This
state continued from several seconds to several minutes and could be observed
several times during an experimental session. In 12 monkeys that
displayed orienting or aggressive response to the ball, visual signs
of inhibition were not observed under these conditions. Further
physical restraint (fixation of hands and trunk) resulted in the
'hypnotized' behavior. This is in contrast to the more usual behavior
of monkeys, what the authors of the article call the 'freedom reflex'
which results when they are taken from their home cages and placed in
the primatologic chair.
As they describe the EEG observations :
"The electrical activity of monkey brain cortex before hypnosis was
characterized by a robust polyrhythmia and presence of theta- and
beta-rhythms. In one monkey the alpha-rhythm was dominate. During
hypnosis, slow activity (delta and theta) with increased amplitude
appeared, periodically alternating with low-amplitude activity. Power
spectrum maps showed that in the low-amplitude phase the decrease in the
power of all rhythms was paralleled in three monkeys with robust beta-1
rhythm with a predominance in the left hemisphere. In the
high-amplitude phase, delta and theta-rhythms dominated in the right
hemisphere."
...
"The analysis of the coherence and correlation functions showed the
decreased relationship between hemispheres (especially in the frontal
cortical areas) under hypnosis and its increase during relaxation (as
compared to the background)."
...
"The analysis of the EEG showed that in the brain of hypnotized monkeys
interhemispheric asymmetry appears: the domination of the theta-rhythms and
delta-rhythms in the right hemisphere or beta-rhythm in the left
hemisphere - depending upon the phase of hypnosis."
Factors shown to facilitate this "animal hypnosis" include
vestibular (pose in the chair) and somatosensory (fixation) stimuli and
emotional stress (fear), novelty to the experimental conditions,
and additional proprioceptive (restriction of the motor freedom) and
visual influences. Various sources seem to indicate similar
factors which operate on the corresponding 'trance response' in
humans.
In addition to the 'trance reflex' which is seen to sometimes
accompany or precede hypnotic induction, the factor of 'trance logic'
which surfaces under deep trance also adds to the catatonic
appearance, as the primitive language capacity in
trance logic could easily contribute to the appearance of stupor.
But the individual is actually, in general, wide awake and thinking,
and in control of themself, but extraordinarily focused on their
internal experience, and on the voice of the hypnotist.
"... the general tendency of the hypnotic subject to be passive
and receptive is simply expressive of the suggestibility of
the hypnotic subject and hence a direct result of the suggestions
employed to induce hypnosis and not a function of the hypnotic
state."
Milton Erickson, circa 1944.
The most obvious reason to make this distinction is to
dispell the popular myth that a hypnotized person is unconscious
or unable to respond to emergencies, or to oppose the will of the
hypnotist if they should wish to do so. In fact, Erickson did
a famous detailed study of attempts by the hypnotist to force
their will on hypnotized subjects, and observed that not only
did the subjects discriminate what suggestions they would and would not
respond to, and refused to respond to some, but then often came up with
ways to hurt or humiliate the hypnotist in retaliation for the attempt.
And that they were even more selective about what suggestions they
would not respond to under hypnosis than they were normally !
Another reason this distinction is made is because of extraordinary
skills of some hypnotists to 'induce trance' (gain a unique kind of
compliance or communication) with people who had not been prepared or
relaxed by a classical induction, and who in fact steadfastly and
effectively resisted all attempts at classical induction of trance.
A third reason is that we observe in some hypnotic phenomena
that an individual can be hypnotized, with the help of a traditional
progressive relaxation procedure for example, and then "remain
hypnotized" (equally responsive to suggestion) long after leaving
the state of physiological relaxation and classic apparent catatonia.
So, the 'trance,' though it may in fact start with a process similar
to that which commonly leads to sleep, or may start with the 'trance
reflex,' it is not dependent upon stupor, nor even neccessarily
relaxation.
g. Evidence of enhanced functioning following suggestion ?
-----------------------------------------------------------
Some of the 'unusual capacities' often claimed of hypnosis are
actually legitimate, but found to be quite normal capacities seen in
various non-hypnotic situations as well, though the hypnotic 'deep
trance' context does apparently give a unique kind of _access_ to those
normal capacities. Seemingly a product of the unique sort
of attention control found in hypnotic responding.
"Trance permits the operator to evoke in a controlled manner
the same mental mechanisms that are operative spontaneously in
everyday life."
Milton Erickson
T.X. Barber, a highly respected researcher into human
functioning under hypnosis has long promoted the view that people
can bring out their own inner capabilities by direct requests to
think, feel, and experience in a suggested way, without any need
for hypnotic induction. He says that the secret of hypnosis
involves the ability to fantasize in a hallucinatory way
and provide the drama and excitement. Also important, according to
Barber, is the way in which suggestions are given, language which
gives firm but metaphorical suggestions.
Keith Harary, in his March/April 1992 _Psychology_Today_ article,
"The trouble with HYPNOSIS. Whose power is it, anyway ?" reviews a
number of critical studies of hypnosis and concludes a a similar view :
"Packaging them [the true claims made about hypnosis] under the label
'hypnosis' conceals what is really going on. It doesn't even begin
to suggest that they are our very own powers and there might be ways
to get at them directly and entirely on our own."
(1) 'Mind and Body' in medicine
We see that there is little of any consistency that can be said
about light trance objectively, and possibly only 'trance logic' (if
that) as a common characteristic of deep trance. Yet the subjective
experience of the individual is sometimes very profoundly altered.
And some phenomena can be reliably reproduced in good subjects which
are medically considered very unusual and hard to explain (though not
neccessarily limited to hypnosis situations).
The working medical framework that had traditionally cleanly
separated psychogenic from physiological effects has been revised
in parts to allow for some of the mechanisms related to
effects found in good hypnotic subjects; such as influences
between neural and immunological systems, dermatological
(skin) responses that were previously believed not to be
able to be influenced by the brain and nervous system,
and the difficult but demonstrable 'biofeedback' ability to
indirectly control very small neural units previously considered
completely autonomic.
In terms of the prevailing medical paradigm, numerous functional
interconnections within the brain and between the nervous system
and other body systems have been found that may gradually help to
explain such remarkable effects as we see in hypnosis and under
various other seemingly special psychological conditions.
Among other key discoveries, the study of neuropeptides and their
distribution throughout the body as well as the brain provides
some potential answers for some of the more perplexing questions
arising from effects due to suggestion.
Richard Benson's "relaxation response" research pioneered
in this area, and a great many studies since then have validated his
ideas about psychological and physiological functions greatly
influencing each other. Two recent article that are fairly typical
are in the June 1989 issue of the mainstream medical specialty
journal _Gastroenterology_, "Hypnosis and the relaxation response" and
"Modulation of gastric acid secretion by hypnosis."
An excellent review of the research into the exact physiological
effects found to result from hypnotic suggestions in particular may be
found in these two of T.X. Barber's articles ...
"Physiological effects of 'hypnosis,' _Psychological_Bulletin_,
58: 390-419, 1961.
"Physiological effects of 'hypnotic suggestions' :
a critical review of recent research (1960-1964),"
_Psychological_Bulletin_, 63: 201-222, 1965.
In addition to these general references, the following sections may help
to followup on any interest into various specific apparent
unusual effects of suggestion.
(2) Hypermnesia, perceptual distortions, hallucinations
Hypermnesia is perceived enhanced recall of memories. See also the
later section on the reliability of hypnotic recall.
An excellent overview of experimental and clinical studies of
hypermnesia, perceptual distortions, and hallucinations
under hypnosis may be found in the hypnosis section of the
_Annual_Review_of_Psychology_, especially these issues spanning
20 years of research into hypnotic phenomena :
Vol 16, 1965, E. Hilgard, p. 157-180
Vol 26, 1975, E. Hilgard, p. 19-44
Vol 36, 1985, J.R. Kihlstrom, p. 385-418
Another related area is the remarkable phenomena of eidetic
imagery, or 'photographic memory.' In recent years, this
formerly controversial phenomenon has been demonstrated
by means of computer generated random pixel patterns which
stereoscopically encode a visual image. There would be two
images which, one seen by each eye at the same time, produce
a three dimensional visual image. It is considered virtually
impossible to detect the encoded image by looking at the
separate encoded patterns at different times. People with
eidetic imagery can memorize one pattern, and then mentally
project it with one eye while looking at the other pattern
with the other eye. The result is that they can see the
three dimensional image, while apparently no amount of motivation
will permit someone without eidetic imagery to see the final
image.
It is now known that many five year old children can experience eidetic
imagery, and that it is very rare in adults. A study published in the
Journal of Abnormal Psychology in 1975 (and a followup three
years later) demonstrated that the rate of eidetic imagery in adults
hypnotically regressed to age five was comparable to that in actual
five year olds.
This could be interpreted as evidence of true temporal
regression in hypnosis in some sense, although that interpretation
seems unlikely in the face of evidence in other areas. It is
more likely to provide unique evidence of state-specific abilities
accessible through hypnotic suggestion.
The following are the studies quoted above :
Walker, Garrett, & Wallace, 1976, "Restoration of Eidetic Imagery via
Hypnotic Age Regression : A Preliminary Report,"
_Journal of Abnormal Psychology_, 85, 335-337.
Wallace, 1978, "Restoration of Eidetic Imagery via Hypnotic Age Regression:
More Evidence," _Journal of Abnormal Psychology_, 87, 673-675.
In addition, Michael Nash in his chapter "Hypnosis as Psychological
Regression," in Lynn and Rhue's 1991 _Theories_of_Hypnosis_ discusses
the evidence around different kinds of psychological regrression
and also refers to an unpublished manuscript by Crawford, Wallace,
Katsuhiko, and Slater, from 1985, which is said to also discuss
positive evidence for the faciitation of eidetic imagery phenomenon
with hypnotic techniques : "Eidetic Images in Hypnosis,
Rare but There."
(3) Posthypnotic suggestion and amnesia
Amnesia (basically selective forgetting in this case) sometimes
occurs spontaneously in hypnosis, and sometimes happens as the
result of a direct or indirect suggestion to forget something. The
amnesia effect may last a variable time, possibly months or longer,
depending on the psychological significance of the amnesia and the
forgotten material and on the intensity of attempts to recall and
availability of recall cues in the environment.
A posthypnotic suggestion in general is a response to hypnotic
suggestion that extends beyond the boundary of the actual
trance period. Posthypnotic suggestions are often performed
without any knowledge that they were previously suggested
(thus the neccessary link to hypnotic amnesia of this phenomena).
The individual responding to a posthypnotic suggestion and with
amnesia for the source of the suggestion will generally incorporate the
response into their ongoing activities without disruption, in
a similar manner to rituallized actions that we pay little attention
to such as brushing our teeth in the morning or making the
right sequence of turns in our well established route to work
each morning. If the response involves some bizarre action,
the individual will either be confused or typically will come up with
a creative rationalization for the behavior. Very rarely will there
be any awareness of the action resulting from a previous
suggestion.
It is the contention of many experts in hypnotic
work that individuals can and do resist posthypnotic suggestions
that they do not wish to perform, except that implicit trust of the
hypnotist may promote a behavior out of the ordinary. This is
sometimes (especially per Orne) considered more a factor of the
relationship between the hypnotist and subject than a matter of any
capacity to use hypnosis to coerce a person without their knowledge.
The later section on hypnosis and volition will cover this in
grater detail.
See the following sources of information on post-hypnotic
research, in addition to the Hilgard article in Vol. 16
of _Annual_Reviews_ (1965), cited above :
W. Wells, 1940, "The extent and duration of post-hypnotic amnesia,"
_Journal_of_Psychology_, 9:137-151.
Edwards, 1963, "Duration of post-hypnotic effect,"
_British_Journal_of_Psychiatry_, 109: 259-266.
Dixon, 1981, "Preconscious Processing" (book)
Various studies have also been done to try to determine what
kinds of psychological pressure will cause hypnotic amnesia
to be breached, and under what conditions.
Schuyler & Coe, "A physiological investigation of volitional and
nonvolitional experience during posthypnotic amnesia," _Journal of
Personality & Social Psychology_, 40(6):1160-9, 1981 Jun was
a good example.
Highly responsive hypnotic subjects, who were classified as having
control over remembering (voluntaries) or not having control over
remembering (involuntaries) during posthypnotic amnesia, were compared
with each other on four physiological measures (heart rate,
electrodermal response, respiration rate, muscle tension) during
posthypnotic recall. Two contextual conditions were employed: One was
meant to create pressure to breach posthypnotic amnesia (lie detector
instructions); the other, a relax condition, served as a control. The
recall data confirmed earlier findings of Howard and Coe and showed that
voluntary subjects under the lie detector condition recalled more than
the other three samples that did not differ from each other. However,
using another measure of voluntariness showed that both voluntary and
involuntary subjects breached under lie detector conditions.
Electrodermal response supported the subjects' reports of control in
this case. Physiological measures were otherwise insignificant. The
results are discussed as they relate to (a) studies attempting to breach
posthypnotic amnesia, (b) the voluntary/involuntary classification of
subjects, and (c) theories of hypnosis.
(4) Pain control (analgesia and anesthesia)
Hypnosis was at one time frequently and sucessfully used for surgical
anesthesia. It is still sometimes used effectively for dental work,
childbirth, and chronic pain of various types. Pain control is one
of the most reliable and most studied of the hypnotic phenomena.
In addition to Hilgard's article in Vol 26 of _Annual_Reviews_ (1975)
see :
Hilgard, Hilgard, Macdonald, Morgan, and Johnson, 1978,
"The reality of hypnotic analgesia : a comparison of highly
hypnotizables with simulators." The authors find that
motivated simulation of hypnotic analgesia is easily distinguished
from hypnotic analgesia.
Hilgard and Hilgard, 1983, "Hypnosis in the relief of pain" (book)
In 'Evaluation of the efficacy and neural mechanism of a hypnotic
analgesia procedure in experimental and clinical dental pain,' 4,41-48,
_Pain_, 1977, J. Barber and D. Mayer reported that effective
analgesia was produced by a refinement of hypnotic technique, and was
not reduced by naloxone. J. Barber, neuropsychiatry at UCLA, seems to
have somewhat specialized in this area.
Another 1977 study, Stern, Brown, Ulett, and Sletten, 'A comparison of
hypnosis, acupuncture, morphine, Valium, aspirin, and placebo in the
management of experimentally induced pain,' Annals_of_the_New_York_
Academy_of_Sciences, 296, 175-193, found that acupuncture,
morphine, and hypnotic analgesia all produced significantly reduced
pain ratings for cold pressor and ischemic pain.
Van Gorp, Meyer, and Dunbar, 'The efficacy of direct
versus indirect hypnotic induction techniques on reduction of
experimental pain,' International_Journal_of_Clinical_and_Experimental_
Hypnosis, 33, 319-328, 1985 (with cold pressor pain).
Tripp and Marks, 1986, compared hypnosis and relaxation
with regard to analgesia for cold pressor pain in 'Hypnosis, relaxation,
and analgesia suggestions for the reduction of reported pain in high-
and low-suggestible subjects,' Austrailian_Journal_of_Clinical_and_
Experimental_Hypnosis, 33, 319-328.
H.B. Crasilneck et al., 1955, "Use of hypnosis in the management of
patients with burns," _Journal_of_the_American_Medical_Association_,
158: 103-106.
D. Turk, D.H. Meichenbaum, and M. Genest, (1983),
_Pain_and_behavioral_medicine_:_a_cognitive-behavioral_perspective,
New York : Guilford Press has a review of cognitive-behavioral
strategies for pain control in general, not limited to hypnosis.
In Larbig W. Elbert T. Lutzenberger W. Rockstroh B. Schnerr G.
Birbaumer N. EEG and slow brain potentials during anticipation
and control of painful stimulation. Electroencephalography &
Clinical Neurophysiology. 53(3):298 -309, 1982 Mar., EEG corrrelates
of pain control were studied.
Cerebral responses in anticipation of painful stimulation and while
coping with it were investigated in a "fakir" and 12 male volunteers.
Experiment 1 consisted of 3 periods of 40 trials each. During period 1,
subjects heart one of two acoustic warning stimuli of 6 sec duration
signalling that either an aversive noise or a neutral tone would be
presented at S1 offset. During period 2, subjects were asked to use any
technique for coping with pain that they had ever found to be
successful. During period 3, the neutral S2 was presented simultaneously
with a weak electric shock and the aversive noise was presented
simultaneously with a strong, painful shock. EEG activity within the
theta band increased in anticipation of aversive events. Theta peak
was most prominent in the fakir's EEG. A negative slow potential
shift during the S1-82 interval was generally more pronounced in
anticipation of the aversive events that the neutral ones, even though
no overt motor response was required.
Negativity tended to increase across the three periods, opposite to the
usually observed diminution. In Experiment 2, all subjects self-
administered 21 strong shock-noise presentations. The fakir again showed
more theta power and more pronounced EEG negativity after stimulus
delivery compared with control subjects. Contrary to the controls,
self-administration of shocks evoked a larger skin conductance response
in the fakir than warned external application.
(5) Dermatological responses
Some of the most interesting hypnotic phenomena involve the
apparent precision production of subtle skin responses by
suggestion. Allergic reactions, pseudo-sunburns, blisters,
and weals have been produced by suggestion. In addition,
it has long been known that certain highly troublesome skin
conditions have been influenced or healed in some people by
suggestion (with or without hypnotic induction).
See the following for further information on studies of this :
Ullman & Dudek, 1960, "On the psyche and warts :
II. Hypnotic suggestion and warts," _Psychosomatic_Medicine_,
22:68-76
Rulison, 1942, "Warts, A statistical study of nine hundred and twenty
one cases," _Archives_of_Dermatology_and_Syphilology_, 46:66-81.
Asher, 1956, "Respectable Hypnosis," _British_Medical_Journal_,
1: 309-312.
R.F.Q. Johnson and T.X. Barber, 1976, "Hypnotic suggestions
for blister formation : Subjective and physiological effects,"
_American_Journal_of_Clinical_Hypnosis_, 18: 172-181.
Mason, 1955, "Icthyosis and hypnosis," _British_Medical_Journal_,
2: 57-58.
M. Ullman, 1947, "Herpes Simplex and second degree burn induced
under hypnosis, _American_Journal_of_Psychiatry_, 103: 828-830.
(6) Control of bleeding
Experiments with hypnosis during surgery have found that suggestion
during and after surgery can reduce bleeding significantly, as well
as help with the management of pain.
See Clawson and Swade, 1975, "The hypnotic control of blood flow
and pain : The cure of warts and the potential for the use
of hypnosis in the treatment of cancer," _American_Journal_of_
_Clinical_Hypnosis_, 17: 160-169.
(7) Cognition and learning
This is a broad area covering a number of factors that are difficult
to separate. In addition to the critical review by Barber in 1965
cited above in (1), see G.S. Blum, 1968. "Effects of hypnotically
controlled strength of registration vs. rehearsal,"
_Psychonomic_Science_, 10: 351-352, which discusses hypnosis as
a possible way of reducing rehearsal needed to learn something new.
In some of his publications, researcher Charles Tart discusses
the concept of state-specific abilities, including the possibility
that some might apply to hypnotic phenomena. See his
_States_of_Consciousness_, and other related works for more on this.
(8) Enhanced strength or dexterity
The effect of hypnotic suggestion in apparently enhancing physical
performance under certain conditions seems to relate to the
unusual control over focus of attention available in hypnosis,
which permits improved concentration and increased motivation
in some athletes, and can be used to modify or lessen the influence
of inhibiting beliefs or attitudes. Similar effects are seen
when athletes are motivated in other ways, outside of hypnosis.
See T.X. Barber's 1966 paper, "The effects of 'hypnosis'
and motivational suggestion on strength and endurance :
a critical review of research studies," _British_Journal_of_
_Social_and_Clinical_Psychology_, 5:42-50.
(9) Immune Response
--------------------
It has long been supposed (and in recent years demonstrated
experimentally) that emotions and psychological state somehow have an
effect on human immune response, but even though detailed mechanisms
and the limits of this effect have not been well understood in modern
medical science. A recent article in Science News, Sept. 4,1993, pp.
153, describes 'the first solid evidence that hypnosis can modify
the immune system far more than relaxation alone."
The report concerns the research of Patricia Ruzyla-Smith of Washington
State University in Pullman and her co-workers, who conclude that
"hypnosis strengthens the disease-fighting capacity of two types of
immune cells, particularly among people who enter a hypnotic trance
easily."
This appears to correspond well with and bolster the previous findings
related to enhanced 'placebo' (psychosomatic) effects in good hypnotic
subjects, in the hypnotic induction situation. However, it does not
appear to address the persistent question of whether highly hypnotizable
subjects have a unique capacity for psychosomatic regulation,
or whether they simply exhibit this capacity common to all of us
in a uniquely accessible and convenient way by responding to
hypnotic suggestion.
In this research, the psychologists recruited 33 college students who
achieved a hypnotic trance easily and 32 students who had great
difficulty doing so. Volunteers viewed a brief video describing the
immune system and then were assigned to one of three groups: hypnosis,
in which they listened to a hypnotic induction asking them to imagine
their white blood cells attacking "germ cells" in their body and then
performed this exercise through self-hypnosis twice daily for one week;
relaxation, in which they floated effortlessly in a large tank of warm
water containing Epsom salts and repeated the session one week later;
or neither method.
Students who underwent hypnosis displayed larger jumps in two important
classes of white blood cells than participants in the other groups. The
greatest immune enhancement occurred among highly hypnotizable
students in the hypnosis group.
h. Highly extraordinary experiences while under hypnosis
---------------------------------------------------------
One of the most persistent of the many controversies surrounding
hypnosis is its use in facilitating the recall or (re)experience
of events which are distinctly out of the range of what most people
think of as usual human experiences.
For the present discussion, we might divide these extraordinary
experience into three overlapping types :
(1) Experiences which seem extraordinary because what is remembered
(while under hypnosis) as having previously happened seems to
defy commonly accepted canons of plausibility, such as the
controversial UFO abduction phenomenon,
(2) Experiences which, perceived as happening during hypnosis, seem to
defy commonly accepted canons of plausibility, or would
require a drastic theoretical revision to accept,
such as psychic phenomena,
(3) Experiences which seem extraordinary because they have an
unusually powerful or lasting effect on the individual,
such as certain deeply religious or mystical experiences,
(1) Bizarre remembrances under hypnosis
---------------------------------------
The veracity of events recalled under hypnosis is
considered by most experts today to be problematic to determine.
Hypnosis facilitates the recall of details in good subjects,
and also facilitates the manufacture of details during recall that
were not neccessarily present previously. This in fact is
characteristic of recall in general, which has been demonstrated
to be far from a permanent and unchanging record, but more a
dynamic and adaptive process; a shape-shifting moire pattern
of sorts, conforming to inner needs and ongoing mental activity,
more than a videotape recording of the precise details of perceptual
events.
There is also some evidence that hypnosis may additionally aid in
providing 'state-specific' context to aid in the recall of information
and experience of which the individual is otherwise normally unaware.
Which of these complex and incompletely understood processes
is dominant in the recall of someone's extraordinary memories
of seemingly implausible events is extremely difficult if not
impossible to determine from the hypnotic session alone.
Neither claims of unimpeachable veracity under hypnosis
(the 'hypnosis as truth serum' idea) nor those of hypnosis
being completely unreliable in facilitating recall ('false memory')
stand up to close scrutiny as a general principle applicable to all
cases of controversial hypnotic recall. The best evidence available
seems to indicate that hypnotic methods can sometimes be valuable in a
number of ways, both to the individual's psychological health and in
helping to gather factual information, but that they should not be
relied upon by themselves or given special preference over other
kinds of testimony for such things as legal evidence, nor
considered to be accessing anything like a perfectly faithful
permanent record of past perceptual events.
This section closes with an illustrative philosophical excerpt from a
recent book investigating perception, memory, and consciousness,
based on years of observation of synesthesia (cross-sensory
perception); "The Man Who Tasted Shapes: A Bizarre Medical Mystery
Offers Revolutionary Insights into Reasoning, Emotions, and
Consciousness," Richard E. Cytowic, MD,
Jeremy Tarcher/Putnam Publishing 1993, ISBN 0-87477-738-0 :
(Excerpt begins)
"While pointing out the overlap between emotion and memory, I want
to emphasize that memory is not simply a fixed look-up table. It
too is a creative process during which the state of the brain's
electrical fields change. The sensory cortices generate a
distinct pattern for each act of recognition and recall, with no
two ever exactly the same. They are close enough to cause the
illusion that we understand and have seen the event before,
although this is never quite true. Each time we recall something
it comes tainted with the circumstances of the recall. When it is
recalled again, it carries with it a new kind of baggage, and so
on. So each act of recognition and recall is a fresh creative
process and not merely a retrieval of some fixed item from
storage."
"Furthermore, persons, objects, and events are not perceived in
their entirety but only by those aspects which are, have been, or
can be experienced and acted upon by an observer... "
"... All that we can know about anything outside ourselves is what the
brain creates from raw sensory fragments, which were actively
sought by the limbic brain in the first place as salient chunks
of information..."
" ... Put in a more familiar context, artists and creative writers look
at the world in a certain way. It is the same world that everyone
else sees, but seen differently. Contemporary people often call
artists weird because they do not seem to be seeing the same
things that the majority sees. It is critical to realize that the
sensory gateways that feed into the brain establish their own
conditions for the creation of images and knowledge. Artistic
giants knew full well that their visions were not shared by most
people. Even when persecuted or abandoned because of their vision
artists persist. That is all the can do because their visions are
their reality, and for many of us they subsequently become our
reality when we experience their art."
(copyright (c) Richard E. Cytowic, MD)
(2) Psychic phenomena under hypnosis
-------------------------------------
There are a number of links between the sorts of situations commonly
associated with hypnosis, and the experience of what are often called
'psychic phenomena,' (herein primarily meaning apparent extrasensory
perceptions, and psychokinesis, but also such related experiences as
apparitions mediumistic phenomena, and such strange occurrances
as the apparent suspension of death).
Hypnosis has a strong historical connection with spiritualism,
as evidenced partly by the shared traditional emphasis on 'trance,'
especially 'trance' appearing as a stupor (contrasted with the
confusing notion of an 'alert trance' or 'waking trance' in some kinds
of hypnotic situation). Spiritualism, in turn, has very strong
associations with both the origins of various schools of psychology,
and modern parapsychology, and the study of 'psychic phenomena'
in general. The reason for quoting that term here is to emphasize that
the term originally meant such subtleties of mental life
as what we today often think of as the'subconscious' or 'unconscious'
mind, rather than specifically and exclusively such things as ESP,
hauntings, or poltergeists. At the time, it seems there had been
less of a feeling that there was a distinct difference in
plausibility between 'unconscious processes' and those today
generally considered paranormal. Because of this, the term may tend
to be ambiguous when used in a discussion where a wide variety
of experiences are being included.
Early (circa late 19th century, early 20th century) psychology was
largely a philosophical endeavor, which included a wide range
of areas of investigations that were grouped in ways that might
seem a little strange today. For example, the American Society of
Psychical Research (ASPR), today probably thought of mostly as having
been a pioneering organization in the study of the paranormal, devoted
a great deal of its early efforts (and an explicit section of its
charter) to studying what we today usually consider mundane aspects
of hypnosis.
Hypnosis has thus long had a popular traditional
association with such controversial psychic phenomena as ESP,
PK, poltergeist activity, and clairvoyance, as well as various
forms of occultism and some kinds of religious healing rituals.
Of particular pertinence here, there is also a tenuous but
persistent experimental link between hypnotic processes and
laboratory psi. The link is particularly prominent in
anecdotal evidence, but this is often of questionable
reliability, for reasons that will be described here.
It is in the more controlled laboratory psi data that
the more truly demonstrable anomalous results appear that
give us cause for further investigation.
First, the difficulty with this sort of experiment, and the kinds of
protocols and controls required should be recognized. While
the open-minded researcher of anomalies might not wish to reject the
useful subjective verbal reports of hypnotic subjects, they also
have to contend with the remarkable subtlety of non-paranormal
(conventional sensory) human perception and communication.
Milton Erickson, for example, described an experiment with
hearing impaired 'lip readers.' He discovered that they actually
read a much richer panorama of cues than simply the moving
lips. The lip reading subjects would sit with their backs to a
blackboard on which there were various geometric designs. The
designs were then covered with sheets of paper. In front of the lip
readers sat a group of non-hearing-impaired participants, who were
instructed to look at the blackboard and say and do nothing. Someone
else removed the paper covering the geometric symbols, one at a time.
The lip readers were instructed to write down anything that they read
from the participants in front of them who were observing the
geometric figures.
The lip readers were able to "read" the names of the geometric figures
apparently from their partner's faces, with varying degrees of
accuracy. One subject, a diagnosed paranoid psychotic, who believed
they heard other people's thoughts about them, was reported as having
perfect accuracy.
Erickson applied this insight to his hypnotic technique, by recognizing
the significance of messages he himself didn't realize he was
giving. A similar analysis has frequently been applied to
anecdotal reports of cases of apparent telepathy, but where
'cold reading', or the skill of gathering information surreptitiously
through subtle but conventional sensory clues, appears to be a likely
factor.
Someone might actually suggest that the paranoid psychotic patient in
this particular experiment, and some or all of the other hearing-
impaired patients, were actually employing some telepathic faculty to
some degree. But most interpretations would probably focus on the use
of subtle clues that the participants observing the blackboard were
unaware of providing. The nature of hypnotic communication
('rapport') is such that the participants are particularly well
attuned to the nuances of each other's movement, speech and
expression. This, combined with the lip readers' existing
capacity for attending to subtle body language,
contributes to the appearance of an even more extraordinary, even
paranormal, information transfer, and makes it more difficult
to sort out the precise mechanisms of information transfer involved.
Modern psychological reviews might also focus on the hypothesis that
the paranoid psychotic subject was likely dissociating their
perception of what they were reading from their awareness of its source
(rather than the obvious appearance of receiving it from an
extrasensory source). This resembles the dissociation theory of
how trance mediumistic (trance channelling) behaviors and some
religious experiences (such as hearing the voice of God) may occur,
at least in some cases. The concept of cognitive dissociation is a
central one to many modern psychological descriptions of hypnotic and
peripheral phenomena, as we will see in more detail later. In
particular, we will see that dissociation provides an extremely useful
description, but not neccessarily an adequate explanation of all of
the data.
Today, most psychologists, and virtually all of those investigators
known as parapsychologists, are aware of the complexity of human
perception under even conventional circumstances. They would generally
tend _not_ to consider a psi hypothesis to be demonstrated in this
sort of situation, given the apparently demonstrated correlation of
exceptional body language reading skills and high hit rates.
This is of course entirely different from demonstrating that
a psi faculty is _not_operating_. Just that the experimental
situation in this particular case does not provide evidence of psi.
But there are other experimental results, with protocols more
specifically designed to rule out subtle conventional sensory
communication. These give us reason to at least consider and test a
psi hypothesis, with an eye toward ruling out subtle body reading
effects, in hypnotic situations. It appears from some results that
under certain kinds of conditions hypnosis may at least be slightly
conducive to anomalous information transfer, even when subtle cues are
eliminated.
One well known difficulty of even this result, though,
is that it is not clear whether hypnosis is facilitating some
elusive 'ESP' faculty in some general way, or more specifically
improving the percipient's ability to perform on the particular kinds of
tests in use. In other words, the dramatic interpretation of
hypnosis as an altered state in which paranormal
capacities are provided or enhanced may not be the best or only
explanation, even if the psi hypothesis itself were to receive
growing experimental support. There is also the crucially important
matter of just exactly what it is _about_ the process of hypnotic
induction and its effects on the subject that changes hit rates
in certain laboratory psi tests.
In another section, we briefly review T.X. Barber's work demonstrating
that most if not all of the unusual phenomena reported during hypnosis
are also seen under other conditions. He and his colleague Sheryl
Wilson in their work on the theory of the 'Fantasy Prone
Personality' also provide us with another link between psi and
hypnosis, the observation that there are distinct similarities
in personality variables between people who are excellent hypnotic
subjects, and those who report large numbers of psychic
experiences.
It should be emphasized here that this theory does
not support the once popular notion that good hypnotic subjects
are simply gullible or neurotic, or otherwise mentally ill; as no
correlation with any of these personality variables has ever been
determined. Rather, the FPP theory paints a picture of natural
visionary individuals with a rich inner life and often extraordinary
psychosomatic responses, but who are perfectly well able to
distinguish their vivid fantasy life from reality, just as most of us
can distinguish a dream from a memory of actual events, most of the
time.
In other words, among the factors that the FPP does NOT correlate with
well at all is any diminished capacity for reality testing. This
should be born in mind particularly because of the popular
connotations of the term 'fantasy-prone,' and the questionable veracity
of recollections occurring under hypnotic procedures. A report from
an FPP subject is not inherently either more or less reliable than one
from other subjects, in or out of hypnosis. Their rich mental life
does not neccessarily intrude on their external perceptions, except
under various very unususal kinds of conditions, such as
spontaneous hallucination triggered by hypnotic suggestion.
Additionally, there is the complex psychological question of whether
the individual interprets their experience as 'real' or
'imagined.' When an LSD user comes down from their trip,
they don't generally continue to believe that their face was melting
or that the sky actually changed to flourescent green during their
experience, they distinguish it as an 'altered state.' However,
during the trip, the altered perception may be quite convincing.
In hypnotic extraordinary experiences, we find both cases
where the individual believes that their perceptions were due to an
altered state, even though it seemed real at the time, and those where
they believe something quite bizarre actually happened, not the
result of an unusual perceptual state. And the two
types of cases are not at all easy to distinguish by any means other
than relying on the report of the subject.
It has also been observed that even a polygraph is
of extremely limited value in distinguishing whether a bizarre
occurrance actually happened to an individual or was hallucinated
or 'confabulated.' In many cases, the individual believes that
a hallucinated or hypnotically constructed event happened, when
unambiguous independent historical records indicate that it did not.
The particular conditions under which spontaneous hallucination
can occur, and under which they can be confused with external
perceptual experiences are not well known, nor is there any known
method of distinguishing a spontaneous hallucination from an external
sensory perception. Even theories of how drug action
(e.g. LSD) causes hallucinations are highly speculative, and
spontaneous hallucinations are much more slippery.
Two current theories of spontaneous hallucination concern
changes in the chemical environment of endogenous
neurotransmitters or neuromodulators which influence
perception (endorphins and serotonin being the most commonly
cited); and possibly some unique mode of function of temporal or
temporolimbic brain pathways, perhaps influenced by electromagnetic
fields.
How these unusual brain conditions relate to psychic phenomena
and to other observations related to hypnosis in general is not
yet well established.
i. Dissociation vs. Suggestibility
---------------------------------------------------------
(1) Dissociation and Suggestibility : A Meaningful Grouping of Traits ?
The dissociation idea, originating in psychoanalytic theory, and historically
strongly linked to neuropathology, has held its ground for many years though
its limitations are now becoming apparent. The term is used for such diverse
conditions as unusual experiences of personal identity sense, the appearance
of automatisms, and the splitting of apparent intentions in behavioral
responding. These different senses of dissociation require some future
research to explain their relationship and underlying mechanisms, as well as
the crucial relationship between dissocation and hypersuggestibility.
The original conception of dissociation was as an anxiety defense
strategy, a way of avoiding 'stress,' while gratifying other psychological
needs. Without the emphasis on an anxiety defense, this idea persists today,
as one standard medical reference puts it :
"... A process whereby specific mental contents
(memories, ideas, feelings, perceptions) are lost to
conscious awareness and become unavailable to
voluntary recall..." (16th ed. Merck Manual)
This seemingly straightforward view of dissocation as mental contents lost to
conscious awareness, and as an anxiety defense, is complicated however by the
psychoanalytic tradition that organic disease can result from harbored
resentments, disease which appears in a metaphorical form expressing the
patient's unconscious feelings in a symbolic physical way. This provides a
link between dissociation and psychosomatic effects. "Hysterical" or
"conversion" symptoms are of psychogenic origin, and mimic organic diseases
(as opposed to organic diseases being the result of psychological stresses).
Such conversion symptoms consist of about 5% of the 'neuroses' or minor
anxiety disorders treated by psychiatrists, according to one 1980 study.
Typical examples are unusual allergic reactions, simulated pregnancy, pseudo
2nd-degree sunburns, hysterical blindness or deafness, visual or auditory
hallucinations, and other sensory or motor aberrations. Conversion symptoms
appear temporary, though they may 'move' from one type or body system to
another as each is addressed therapeutically.
Conversion symptoms and other psychosomatic effects are associated with high
hypnotizability scores on standard scales, and also with a previous history of
conversion and dissociative symptoms, implying a stable trait-like quality.
This quality appears to have a genetic aspect and an early developmental
trigger as well. The correlation of psychoanalytic dissociation and hypnotic
suggestibility is further supported by the observation that hypnosis is
frequently helpful in alleviating conversion symptoms, yet often results in
symptom substitution, and that hypnosis is also frequently helpful in
dissociative disorders as well.
(2) The Effects of Suggestion : From the Supernatural to the Mundane.
Scientists have studied procedures identifiable as hypnosis for 200 years.
Most of the detailed investigation took place between 1950 and 1980.
This was before the current medical research into the chemical links among the
body systems took place. Links between the nervous and immune systems have
been of particular interest recently, along with their significance in health
and disease. A large percentage of the earlier research into hypnosis went
into demonstrating that suggestion (traditionally an agent in the shadowy
realm of the psyche) could influence various autonomic body systems in
an observable manner. Today this result is considered unremarkable.
However, before the days of hypnosis and biofeedback research (and before the
discovery of neuropeptides, cytokines, and other mediators of autonomic
functions), this was considered an incredible, even supernatural claim.
The classic hypnosis research also demonstrated that some or all people respond
differently to suggestion under different conditions. Relatively little work
has gone into determining the precise details of how each suggestion effect
occurs, because so much of the focus has been on determining that 'something
happens.' The situation is not too far from what we come across in modern
anomaly research. In both areas, we need to move forward to detail what is
going on in each case, rather than simply prove that something interesting is
happening.
Today, there is basic agreement among most researchers that such a thing as
hypersuggestibility does occur in some sense. This means that under certain
conditions, unusual feats of attention control, psychosomatic regulation,
perceptual distortion, and cognitive dissociation can be consistently produced
in some subjects, whereas under other conditions the same subjects can
seemingly not deliberately produce those same behaviors. Opinions are split
about exactly what conditions cause hypersuggestibility; i.e., whether it is a
unique biological state or whether it is the result of responding to the
social demands and expectations of the situation. Also, there is controversy
over the relationship between hypersuggestibility and cognitive dissociation.
Another thing that most researchers today do agree on is that hypnosis is
not the only procedure whereby such hypersuggestibility (or dissociation)
may be produced.
(3) Two "psychosomatic types," the Fantasy Prone and the Alexythymic
The seeming loose correlation of psychosomatic symptoms, hypnotizability, and
'fantasy proneness' (in the Barber and Wilson sense ) seems almost too neat a
correlation to be true, and it probably is too neat to be true.
Common clinical observation is that the typical psychosomatic patient, the
alexythymic (term coined by Nemiah and Sifneos), is unable to verbalize
emotions or to sustain elaborated mental representations. A number of
psychoanalysts have noted that psychosomatic patients engage in primarily
'operational thinking,' are typically highly oriented toward the concrete, at
least in therapy, that they show marked poverty of imagination and
symbolization.
This is the opposite of what we would expect from the prototype "fantasy prone
personality," (of Wilson and Barber, for example) who might well be described
as an imaginative and even visionary individual. This seems to tell us that
psychosomatic effects are not as limited to a particular personality type as
some theories in the past had proposed. It also seems to further implicate
internally-directed emotional self-awareness as a factor in intentional
control of psychosomatic regulation, rather than in psychosomatic illness
(or healing) itself. This also makes sense in light of the various theories
which propose that the limbic system, in conjunction with the frontal cortical
lobes, is critical for intentional psychosomatic self-regulation.
(4) Dissociation versus Situational Factors.
Evidence has been mounting steadily that different distinct 'states' of the
nervous system can occur in the same person at different times, and even in
the same person at the same time, illustrating the apparent biological
capacity for dissociation.. The former is demonstrated in the rare condition
of Multiple Personality Disorder. The latter is demonstrated in the bizarre
perceptual anomaly of blindsight, where brain-damaged visually impaired
individuals can be demonstrated to have a kind of perception in their
consciously blind visual field. In addition to this evidence of cognitive
dissociations, evidence has also been mounting emphasizing the influence of
personal and social expectations on human behavior. Teasing apart what state
factors are most important and what situation-related expectations are most
important in any given situation is a crucial matter for future research.
The controversial case of the 'hidden observer' in hypnotic analgesia
(apparently independent responses from the same person at the same time under
certain experimental conditions) appears to be swaying the argument in favor
of a dissociation view of hypnosis in the case of exceptional subjects, but
this debate is likely not over yet. It seems likely that social psychological
factors will need to be considered as well in considering how suggestibility
varies.
(5) Hypnosis as distinct from Suggestion
Current theoretical frameworks appear to be moving toward an even clearer
distinction than we had in the past between the hypnotic induction process and
the resulting condition of hypersuggestibility. Most classical hypnotic
induction is indistinguishable from other means of helping to induce a relaxed
condition in the body. Also, a number of experiments have demonstrated
enhanced suggestibility under conditions where the body is not relaxed
(suggestion works outside of hypnosis).
The common links between most situations of hypersuggestibility appear to be
a narrow selective focus of attention and a willingness to suspend judgement
and follow a lead uncritically (or wilingness to consider ideas that would at
other times seem bizarre). These seem to result from such diverse
conditions as sensory isolation, relaxed attentiveness, and extreme fear.
There does not appear to be a single common general EEG pattern in
hypersuggestibility, or which makes hypnotized individuals distinguishable
from awake ones, though there are hints of possibly unique evoked potential
responses during periods of enhanced suggestibility.
One of the more intriguing recent theories is that hypersuggestibility
may somehow also be mediated by the immune system and other chemiclly linked
autonomic systems rather than the brain alone. A two-way chemical feedback
loop has been discovered to operate between the nervous and immune systems,
but it will take further research to determine its relationship to
suggestibility and psychosomatic illness and healing in general.
(5) What is the neurobiological basis of suggestibility and of
dissociation?
Traditional cortical inhibition theories hold that hypersuggestibility is the
result of inhibition of the cerebral cortex (and thus the usual 'critical
faculties') due to some sort of override by lower brain centers. This has
proven to be an overly simplistic way of looking at it. A more recent version
of that former Pavlovian theory is that the left cerebral hemisphere is
somehow selectively inhibited during conditons of hypersuggesibility.
This is an expression of the popular culture view of 'left-brained'
and 'right-brained.' As for most behavior, there will likely be evidence for
a differential contribution from the asymmetric cerebral hemispheres in
hypersuggestibility, but so far differential hemisphere activity itself does
not seem to be the primary mechanism of enhanced suggestibility.
We have good reason at this point to think of enhanced suggestibility as a
common endpoint toward which a number of methods can lead in some or all human
beings. Hypnotic induction is only one of these methods. There are also very
good indications that there is something special about some forms of
dissociation that merits further investigation into just what cognitive
functions become split, under what conditions these splits occur, and how they
occur. It is also of great interest how dissociation relates to various
anomalous phenomena (such as extrasensory perception, psychokinesis, and
others) that have long been associated with 'dissociative states.'
-------------------------------------------------------
3. How reliable are things remembered under hypnosis ?
-------------------------------------------------------
This has often arisen as both a legal issue (as in the
reliability of testimony obtained during or after hypnotherapy)
and also a social issue (regarding the use of hypnotherapy to
establish evidence of early child abuse, for example).
It is entirely true that subjects under hypnosis frequently
recall past forgotten events (or 'repressed' memories in the jargon
of psychoanalysis indicating an active role of the individual
in forgetting as a defense mechanism).
It is also true that people under hypnosis often 'remember'
things quite vividly that never actually happened, but which
have great personal significance nonetheless. Psychiatrist William
Sargant was one of the first to document the therapeutic
benefit of emotionally charged experience, or abreaction,
of fantasized life events, including with the aid of barbiturate drugs.
This is one of the defining characteristics of deep trance hypnosis
in fact, (and various similar conditions), the intensity of fantasies
as well as memories, and the temporary inability to distinguish the
two. This characteristic of trance is what makes is possible to use
hypnotherapy to alter personal history in order to reduce the traumatic
effects of past events on an individual's functioning.
Not simply a reliving or 'catharsis' of the trauma, but
sometimes a lasting modification of the interpretation of the memory
can and does occur in many cases.
This apparent violability and fallibility of human memory is frequently
downplayed in discussions of hypnotic recall because of the already
difficult time that legitimate victims of abuse have in proving what
happened to them. It's not the intention here to make life more
difficult for abuse victims, only to point out that hypnosis
doesn't neccessarily solve their problem of digging out facts from
old memories as neatly as we'd like it to.
The illusion of unusual veracity of hypnotic recall appears to come
from at least two main sources :
1. Older models of human memory as a simple recording and playback
mechanism which preserved extreme details of everything
perceived, and which could be played back in an enhanced
way under certain conditions, like hypnosis.
2. The vividness and subjective meaningfulness often attributed
to experiences under hypnosis partly as a result of the
unique characteristics of hypnotic imagery.
Recognizing the potential difficulties arising from what some
social advocates call 'false memory syndrome,' several states in the
U.S. now confine legal testimony to that obtained prior to any
systematic hypnotic treatment.
In 1985, a committee commissioned by the American Medical Association
cautioned against the systematic use of hypnosis for recollection
for both its unreliability (the possibility for example of
'confabulation,' the creation of stories out of whole cloth to help
fill in missing memories) and its potential to create vivid
false memories with an artificially induced sense of certainty.
In addition to the previously provided references for hypermnesia,
here are some more specifically devoted to the limitations of
hypnotic recall :
D. Spiegel et al, 1989, "Hypnotic alteration of somatosensory
perception," American_Journal_of_Psychiatry.
Loftus and Loftus, "On the permanence of stored information in the
human brain," _American_Psychologist_, 35(5):409-420 (May,1980),
critically evaluates the data gathered by neurologist Wilder Penfield
who had once believed he had discovered during the probing of the
brains of epileptic patients a 'sequential record of
consciousness' similar to the old tape-recorder model of human
memory.
No one yet knows exactly how human memory works in all its details,
but the view of hypnotic recall as potentially highly fallible
is also supported by clinical experience and experimental data.
Milton Erickson called the vivid experiences under hypnosis
'vivification,' and describes how a vivified image is experienced,
regardless of whether remembered or constructed :
"... They are subjectively experienced as external
events rather than as internal processes, with a
consequent endowment of them as reality experiences."
"... They identified it with actual past experiences
and thus endowed it with a subjective validity."
"... They 'created a reality' that permitted a responsive
functioning in accord with the demands of the experiment."
Are there identified physiological correlates for such vivid
recollections or re-creations of past events ? One controversial
researcher, Michael Persinger, has written hundreds of articles,
many of them controversial, on the subject of neurophysiological
correlates of extraordinary experiences of all kinds.
He has reportedly reproduced something like ecstatic mystical states
with the help of electromagnetic stimulation of the cortical temporal
lobes of human subjects, and facilitated vivid imagery akin to UFO
abduction experiences.
He is not alone in the observation of what is sometimes known
as 'clinical mysticism,' which is seen in some forms of temporal
lobe epilepsy and in mechanical stimulation of areas of the temporal
lobes, but he is somewhat unique in his repeatedly published
insistence that all or virtually all unexplained pheonomena and
seemingly false memories can be traced to electromagnetic effects
on the brain. For an article particularly pertinent to the issue
of hypnotic recall, see :
Persinger MA. Neuropsychological profiles of adults who report "sudden
remembering" of early childhood memories: implications for claims of sex
abuse and alien visitation/abduction experiences. Perceptual & Motor
Skills. 75(1):259-66, 1992 Aug.
"Six adults, who had recently experienced sudden recall of preschool
memories of sex abuse or alien abduction/visitation, were given complete
neuropsychological assessments. All experiences "emerged" when hypnosis
was utilized within a context of sex abuse or New Age religion and were
followed by reduction in anxiety. As a group, these subjects displayed
significant (T greater than 70) elevations of childhood imaginings,
complex partial epileptic-like signs, and suggestibility.
Neuropsychological data indicated right frontotemporal anomalies and
reduced access to the right parietal lobe. MMPI profiles were normal.
The results support the hypothesis that enhanced imagery due to temporal
lobe lability within specific contexts can facilitate the creation of
memories; they are strengthened further if there is also reduction in
anxiety." (Taken from an on-line abstract).
If there is anything to this 'temporal lobe lability' hypothesis,
it seems well worthwhile investigating its relationship to
hypnotic suggestibility, and the hypothetical 'Fantasy Prone
Personality' of Barber and Wilson.
As for recall under hypnosis, the experimental observation seems
to be that the subject is uniquely motivated to remember details,
but also uniquely capable of making up details and experiencing them as
if they were remembered.
In Lynn and Rhue's 1991 _Theories_of_Hypnosis_, Robert Nadon et al.
discuss a representative example of experiments in eyewitness
recall with the aid of hypnosis. Subjects were shown a videotape
of a mock armed robbery. They were then asked to recall specific
aspects 6 times :
Twice immediately after seeing the film.
Twice a week after seeing the film.
Once during hypnosis.
Once after hypnosis.
The result was that high hypnotizability subjects (SHSS:C)
recalled more cumulative items in hypnosis than they
did just before hypnosis. Low hypnotizability subjects
did _not_ remember more during hypnosis. This matches our
expectation of hypermnesia, that hypnosis facilitates recall
for good hypnotic subjects.
Most interestingly, _both_ high and low hypnotizability subjects
also made more cumulative _ERRORS_ during hypnosis than just
before hypnosis, though the effect was stronger with
highly hypnotizable subjects.
One explanation of this kind of result from experiments
is that the hypnotic context causes subjects to adopt a looser
reporting criterion, and they are motivated to produce more
information, containing both correct and incorrect (where
there is no clear memory) details. See Klatzky and Erdely,
1985, "The response criterion problem in tests of hypnosis and
memory," _International_Journal_of_Clinical_and_Experimental_
Hypnosis_, 33, 246-257 for further discussion of this
report criterion issue.
4. Can anyone be hypnotized, or only certain people ?
a. Hypnotizability
Using standardized induction scripts and classical induction
techniques, some people are found to be markedly more hypnotizable
than others. Aside from a requisite minimum intelligence for
language and capacity to follow instructions, there are some
other stable characteristics that seem to relate to hypnotizability,
though they do not appear to relate directly to anything that
we ordinarily consider personality traits (such as the stereotype
of gullibility and so on).
An exceptionally skillful operator can individualize their approach and
thereby reduce the number of 'unhypnotizable' or 'resistant' subjects
quite a bit, but there are still some people that respond much
more easily than others to hypnotic suggestion, especially with
regard to 'deep trance' phenomena. This responsiveness appears
to show high test-retest reliability, even after many years.
There are 12 standard tests in the SHSS (Stanford Hypnotic
Susceptibility Scale) which measure how well a subject
conforms to the behavior of a classically hypnotized person.
By these scales, about 5% of people are classically unhypnotizable,
most people show moderate scores, and about 10% are hypnotizable
to extreme depths and show the classical deep trance phenomena
such as somnambulism, visual and auditory hallucinations,
and ability to remain deeply in hypnosis with eyes open.
As mentioned, hypnotizability does not appear to show any obvious
correlation with any of the usual personality traits or
characteristics. Not only is gullibility not directly
correlated, but gender, extraversion/introversion, and neurotic
tendencies have also been shown not to correlate well with
hypnotizability.
There is some tentative evidence that physiological response to
suggestion is influenced by certain forms of sensory deprivation
or isolation. For example, see Barabasz and Gregson, "Antarctic
wintering--over, suggestion and transient olfactory stimulation: EEG
evoked potential and electrodermal responses." in Biological
Psychology. 9(4):285-95, 1979 Dec.
EEG evoked potential and electrodermal responses to real and
suggested olfactory stimulation were recorded on a team of nine
men who wintered -over at Scott Base, Antarctica. Multi-variate
analysis of variance findings indicated some consistent trends
despite adverse conditions and marked inter-individual
differences. Consistent with studies of secondary afferentation
olfaction-related EEGs were evidenced in the occipital area (O1
and O2) as well as the temporal area (T3 and T4). Skin
conductance (SC) showed significant responses for real and
suggested odorants pre and post wintering-over. Suppression of
EEG amplitudes for real and suggested stimuli was evidenced prior
to wintering-over. Following wintering-over experience
suppression of EEG amplitudes for real stimuli showed a decrease
while suppression increased for suggested stimuli. The
implications of the suggestion findings are discussed in possible
explanation of the apparent conflict between different sources of
information about human responses to isolation in the Antarctic
environment.
b. The 'Fantasy Prone Personality'
T.X. Barber and his colleague Sheryl Wilson did some interesting
research where they apparently identitified some loose correlates
to hypnotizability, and which appear to enhance an individual's
capacity to respond to hypnotic suggestion.
Called the 'fantasy prone personality,' (FPP) these correlates do not
seem to form a unitary personality type, but represent a diverse
group of naturally imaginative and visionary individuals.
Josephine Hilgard and other researchers have also found similar
results, that some people have particularly rich inner fantasy lives
and cultivate a lifetime of vivid imagery experience corresponding
to an openness to unusual experience, extraordinary memory in many
cases, capacity for intense concentration, sharp sensory acuity,
and unusually strong somatic responses to mental imagery
(such as response to placebos).
FPP may also describe the people who most frequently report
various psychic phenomena, and 75% of FPP subjects in one study
reported having experienced orgasms from fantasy alone. 65%
reported fantasies of hallucinatory intensity.
This helps support Barber's earlier contentions about hypnotizable
subjects also experiencing similar kinds of phenomena without
specific hypnotic induction.
See Wilson and Barber, "The Fantasy Prone Personality: Implications
for understanding imagery, hypnosis, and parapsychological
phenomena," in _Imagery_,Current_Theory,_Research_,_and_Application_,
from Wiley Press.
c. Can hypnotizability be modified ?
In spite of the fact that hypnotizability frequently remains
constant over time, the capacity to be hypnotized can be
changed to some degree with specific training of various
kinds. The most general requisite capacity, as we saw in the
description of the FPP above is the ability to focus concentration
internally and become extremely absorbed in imaginative activity.
One general review of this work can be found in Michael
Diamond's "Modification of hypnotizability : A review,"
in _Psychological_Bulletin_, 81 : 180-198. Diamond examines
several experiments where music, silence, psychedelic drugs,
biofeedback, sensory deprivation, hypnotic behavioral training,
operant conditioning, and relaxation training were used to attempt
to modify response to hypnosis.
Another review can be found in Wicramasekera's 1976,
_Biofeedback,_Behavior_Therapy_,and_Hypnosis_, which proposes
that imagination training, suggestions for adventurousness,
use of psychedelic drugs, sensory deprivation, and biofeedback training
all can have a lasting effect on hypnotizability.
A different approach is that taken by Gorassini and Spanos, 1986,
"A sociocognitive skills approach to the succesful modification
of hypnotic susceptibility," _Journal_of_Personality_and_
Social_Psychology_, 50: 1004-1012. They propose the CSTP,
a program for enhancing certain responses under hypnosis
by training individual's in the individual behaviors used to
measure hypnotic susceptibility. There are likely various different
ways in which suggestion-related responses can be produced,
and we already have seen that objective measures for distinguishing
hypnosis from simulation have not yet been developed, if indeed they
are possible or practical at all. Subjective experiential
response is apparently _not_ modified with the CSTP, at least not
to the degree that 'imagination training' helps modify subjective
response to hypnosis. Spanos suggests that further research
in this area should make more clear distinctions between
_compliance_, _reinterpreting_and_reclassifying_experience_,
and _changes_in_sensory_experience_ in order to further delineate
what is going on in hypnotic responses.
5. Hypnosis, volition, and mind control
a. Is the hypnotist in control of me ?
The exact nature of what we experience as 'will' or _volition_
is an age-old philosophical problem that has yet to
be resolved by brain scientists or psychologists.
Some aspects of hypnotic responding point
out weaknesses in our understanding of the nature of volition,
such as : its exact relationship to conscious _awareness_; the
capacity and limitations of external stimulii (such as
'suggestion') to influence our sensory experience and behavior;
and the details of the patterns by which specific phenomenological
and physiological events influence each other.
The vast majority of hypnosis researchers seem to believe that
the individual has a capacity for volition which may be
influenced but not ablated by hypnotic suggestion. That the
individual under hypnosis is still acting on their own will in
some sense, although possibly with distorted or limited
information presented by the hypnotist. In addition, there
may be influences on their behavior which the subject is not
_consciously_ aware of responding to, or does not report an
_awareness_ of responding to. This has been challenged
by some theorists by questioning the nature of self-awareness
itself in various ways.
The question of volition becomes important when we consider
the long-studied question of whether a hypnotist can
influence an individual to perform behaviors which they would
not 'ordinarily' want to perform, such as to commit crimes or
to injure themselves or others.
This issue arose in part from the commonly held premise
that an individual's character traits are more important than
immediate stimulii in guiding their behavior. Some of the behaviorist
theorists of hypnosis have historically downplayed the stable
traits of individuals and attributed their behavior to a greater
extent to responses to external stimulii. To them, there is less
question of 'ordinary' behavior, and more a matter of conditioned
responses. Andrew Salter's _What_is_Hypnosis_ published in the middle
of this (20th) century is a good representation of that viewpoint.
The likelihood is that the truth lies between stable
character theory and conditioned response theory. There are
seemingly what some call 'ecological' concerns in hypnotic
responding, aspects of an individual's experience that will tend to
be consistent with each other, or to move toward
consistency (one older example being the theory of
'cognitive dissonance').
Individuals can probably be influenced
under a situation of contrived hypnotic imagery to do things
that would ordinarily be considered very unusual, and to do them
at unusual times and places. But there are clearly 'ecological'
limits to this as well.
For example, most studies have sugggested that the individual can and
does _reject_ suggestions of some types, in some way, both during
hypnosis, and in the form of post-hypnotic suggestions, and is not
being coerced directly under hypnosis to act against their 'will'
in any meaningful sense, though they may act under false premises.
A classic early study supporting this view was done by Milton Erickson,
published in _Psychiatry_ in 1939 (2,391-414), "An experimental
investigation of the possible anti-social use of hypnosis."
M.T. Orne's similar view is represented by his chapter
on hypnosis in the 1961 _The_Manipulation_of_Human_Behavior_,
by Biderman and Zimmer (p. 169-215). Orne argues that the
coercion or 'Svengali Effect' sometimes attributed to hypnosis
is an artifact of the hypnotic experimental situation.
However, it has also been shown that an individual can be
tricked by the hypnotist, and possibly led by their trust in the
hypnotist, to perform unusual behaviors in unusual situations,
even potentially dangerous or embarrasing ones. This potential
is well known to fans of 'stage hypnosis,' particularly with
that subset of individual's particularly susceptible to
the dramatic tactics of the stage hypnotist. These tactics are
for the most part different from the classical induction used in
medicine and psychotherapy, relying on surprise, sudden confusion,
social pressure, and other factors not unknown to medical
hypnotherapists, but not normally emphasized by them either.
A classic study which illustrated how far individuals would go
in hypnotic responses to contrived hypnotic situations was
Loyd W. Rowland, "Will Hypnotized Persons Try To Harm Themselves or
Others?", _Journal of Abnormal and Social Psychology_
34(1939):114-117. This study is described in William Corlis | | |
