THE TRUTH AND THE HYPE OF HYPNOSIS
By Michael R. Nash
Scientific American
July, 2001

http://www.sciam.com:80/2001/0701issue/0701nash.html

Though often denigrated as fakery or wishful thinking, hypnosis has been
shown to be a real phenomenon with a variety of therapeutic uses --
especially in controlling pain.

"You are getting sleepy. Verrry sleepy ..."

A waistcoated man swings his pocket watch back and forth before the face of
a young woman seated in a Victorian-era parlor. She fixes her gaze on the
watch, tracking its pendular motion with her eyes. Moments later she is
slumped in her chair, eyes closed, answering the hypnotist's questions in a
zombielike monotone.

Everyone has seen a depiction of hypnosis similar to this one in movies and
on television. Indeed, say the word "hypnosis," and many people immediately
think of pocket watches. But it is now much more common for hypnotists
simply to ask a subject to stare at a small, stationary object -- such as a
colored thumbtack on the wall -- during the "induction patter," which
usually consists of soothing words about relaxation and suggestions to
concentrate.

But is hypnosis a real phenomenon? If so, what is it useful for? Over the
past few years, researchers have found that hypnotized individuals actively
respond to suggestions even though they sometimes perceive the dramatic
changes in thought and behavior they experience as happening "by
themselves." During hypnosis, it is as though the brain temporarily suspends
its attempts to authenticate incoming sensory information. Some people are
more hypnotizable than others, although scientists still don't know why.
Nevertheless, hypnosis is finding medical uses in controlling chronic pain,
in countering anxiety and even -- in combination with conventional
operating-room procedures -- in helping patients to recover more quickly
from outpatient surgery.

Only in the past 40 years have scientists been equipped with instruments and
methods for discerning the facts of hypnosis from exaggerated claims. But
the study of hypnotic phenomena is now squarely in the domain of normal
cognitive science, with papers on hypnosis published in some of the most
selective scientific and medical journals. Of course, spectacles such as
"stage hypnosis" for entertainment purposes have not disappeared. But the
new findings reveal how, when used properly, the power of hypnotic
suggestion can alter cognitive processes as diverse as memory and pain
perception.

Wheat from the Chaff

To study any phenomenon properly, researchers must first have a way to
measure it. In the case of hypnosis, that yardstick is the Stanford Hypnotic
Susceptibility Scales. The Stanford scales, as they are often called, were
devised in the late 1950s by Stanford University psychologists André M.
Weitzenhoffer and Ernest R. Hilgard and are still used today to determine
the extent to which a subject responds to hypnosis. One version of the
Stanford scales, for instance, consists of a series of 12 activities -- such
as holding one's arm outstretched or sniffing the contents of a bottle --
that test the depth of the hypnotic state. In the first instance,
individuals are told that they are holding a very heavy ball, and they are
scored as "passing" that suggestion if their arm sags under the imagined
weight. In the second case, subjects are told that they have no sense of
smell, and then a vial of ammonia is waved under their nose. If they have no
reaction, they are deemed very responsive to hypnosis; if they grimace and
recoil, they are not.

Scoring on the Stanford scales ranges from 0, for individuals who do not
respond to any of the hypnotic suggestions, to 12, for those who pass all of
them. Most people score in the middle range (between 5 and 7); 95 percent of
the population receives a score of at least 1.

What Hypnosis Is

Based on studies using the Stanford scales, researchers with very different
theoretical perspectives now agree on several fundamental principles of
hypnosis. The first is that a person's ability to respond to hypnosis is
remarkably stable during adulthood. In perhaps the most compelling
illustration of this tenet, a study showed that when retested, Hilgard's
original subjects had roughly the same scores on the Stanford scales as they
did 10, 15 or 25 years earlier. Studies have shown that an individual's
Stanford score remains as consistent over time as his or her IQ score -- if
not more so. In addition, evidence indicates that hypnotic responsiveness
may have a hereditary component: identical twins are more likely than
same-sex fraternal twins to have similar Stanford scores.

A person's responsiveness to hypnosis also remains fairly consistent
regardless of the characteristics of the hypnotist: the practitioner's
gender, age and experience have little or no effect on a subject's ability
to be hypnotized. Similarly, the success of hypnosis does not depend on
whether a subject is highly motivated or especially willing. A very
responsive subject will become hypnotized under a variety of experimental
conditions and therapeutic settings, whereas a less susceptible person will
not, despite his or her sincere efforts. (Negative attitudes and
expectations can, however, interfere with hypnosis.)

Several studies have also shown that hypnotizability is unrelated to
personality characteristics such as gullibility, hysteria, psychopathology,
trust, aggressiveness, submissiveness, imagination or social compliance. The
trait has, however, been linked tantalizingly with an individual's ability
to become absorbed in activities such as reading, listening to music or
daydreaming.

Under hypnosis, subjects do not behave as passive automatons but instead are
active problem solvers who incorporate their moral and cultural ideas into
their behavior while remaining exquisitely responsive to the expectations
expressed by the experimenter. Nevertheless, the subject does not experience
hypnotically suggested behavior as something that is actively achieved. To
the contrary, it is typically deemed as effortless -- as something that just
happens. People who have been hypnotized often say things like "My hand
became heavy and moved down by itself" or "Suddenly I found myself feeling
no pain."

Many researchers now believe that these types of disconnections are at the
heart of hypnosis. In response to suggestion, subjects make movements
without conscious intent, fail to detect exceedingly painful stimulation or
temporarily forget a familiar fact. Of course, these kinds of things also
happen outside hypnosis -- occasionally in day-to-day life and more
dramatically in certain psychiatric and neurological disorders.

Using hypnosis, scientists have temporarily created hallucinations,
compulsions, certain types of memory loss, false memories, and delusions in
the laboratory so that these phenomena can be studied in a controlled
environment.

What Hypnosis Isn't

As scientists discover more about hypnosis, they are also uncovering
evidence that counters some of the skepticism about the technique. One such
objection is that hypnosis is simply a matter of having an especially vivid
imagination. In fact, this does not seem to be the case. Many imaginative
people are not good hypnotic subjects, and no relation between the two
abilities has surfaced.

The imagination charge stems from the fact that many people who are
hypnotizable can be led to experience compellingly realistic auditory and
visual hallucinations. But an elegant study using positron emission
tomography (PET), which indirectly measures metabolism, has shown that
different regions of the brain are activated when a subject is asked to
imagine a sound than when he or she is hallucinating under hypnosis.

In 1998 Henry Szechtman of McMaster University in Ontario and his co-workers
used PET to image the brain activity of hypnotized subjects who were invited
to imagine a scenario and who then experienced a hallucination. The
researchers noted that an auditory hallucination and the act of imagining a
sound are both self-generated and that, like real hearing, a hallucination
is experienced as coming from an external source. By monitoring regional
blood flow in areas activated during both hearing and auditory hallucination
but not during simple imagining, the investigators sought to determine where
in the brain a hallucinated sound is mistakenly "tagged" as authentic and
originating in the outside world.

Szechtman and his colleagues imaged the brain activity of eight very
hypnotizable subjects who had been prescreened for their ability to
hallucinate under hypnosis. During the session, the subjects were under
hypnosis and lay in the PET scanner with their eyes covered. Their brain
activity was monitored under four conditions: at rest; while hearing an
audiotape of a voice saying, "The man did not speak often, but when he did,
it was worth hearing what he had to say"; while imagining hearing the voice
again; and during the auditory hallucination they experienced after being
told that the tape was playing once more, although it was not.

The tests showed that a region of the brain called the right anterior
cingulate cortex was just as active while the volunteers were hallucinating
as it was while they were actually hearing the stimulus. In contrast, that
brain area was not active while the subjects were imagining that they heard
the stimulus. Somehow hypnosis had tricked this area of the brain into
registering the hallucinated voice as real.

Another objection raised by critics of hypnosis concerns its ability to
blunt pain. Skeptics have argued that this effect results from either simple
relaxation or a placebo response. But a number of experiments have ruled out
these explanations. In a classic 1969 report, Thomas H. McGlashan and his
colleagues at the University of Pennsylvania found that for poorly
hypnotizable people, hypnosis was as effective in reducing pain as a sugar
pill that the subjects had been told was a powerful painkiller. But highly
hypnotizable subjects benefited three times more from hypnosis than from the
placebo. In another study, in 1976, Hilgard and Stanford colleague Éva I.
Bányai observed that subjects who were vigorously riding stationary bicycles
were just as responsive to hypnotic suggestions as when they were hypnotized
in a relaxing setting.

In 1997 Pierre Rainville of the University of Montreal and his colleagues
set out to determine which brain structures are involved in pain relief
during hypnosis. They attempted to locate the brain structures associated
with the suffering component of pain, as distinct from its sensory aspects.
Using PET, the scientists found that hypnosis reduced the activity of the
anterior cingulate cortex -- an area known to be involved in pain -- but did
not affect the activity of the somatosensory cortex, where the sensations of
pain are processed.

Despite these findings, however, the mechanisms underlying hypnotic pain
relief are still poorly understood. The model favored by most researchers is
that the analgesic effect of hypnosis occurs in higher brain centers than
those involved in registering the painful sensation. This would account for
the fact that most autonomic responses that routinely accompany pain -- such
as increased heart rate -- are relatively unaffected by hypnotic suggestions
of analgesia.

But couldn't people merely be faking that they had been hypnotized? Two key
studies have put such suspicions to rest.

In a cunning 1971 experiment dubbed The Disappearing Hypnotist, Frederick
Evans and Martin T. Orne of the University of Pennsylvania compared the
reactions of two groups of subjects: one made up of people they knew to be
truly hypnotizable and another of individuals they told to pretend to be
hypnotized. An experimenter who did not know which group was which conducted
a routine hypnotic procedure that was suddenly interrupted by a bogus power
failure. When the experimenter left the room to investigate the situation,
the pretending subjects immediately stopped faking: they opened their eyes,
looked around the room and in all respects dropped the pretense. The real
hypnotic subjects, however, slowly and with some difficulty terminated
hypnosis by themselves.

Fakers also tend to overplay their role. When subjects are given suggestions
to forget certain aspects of the hypnosis session, their claims not to
remember are sometimes suspiciously pervasive and absolute, for instance, or
they report odd experiences that are rarely, if ever, recounted by real
subjects. Taru Kinnunen, Harold S. Zamansky and their co-workers at
Northeastern University have exposed fakers using traditional lie-detector
tests. They have found that when real hypnotic subjects answer questions
under hypnosis, their physiological reactions generally meet the criteria
for truthfulness, whereas those of simulators do not.

Hypnosis and Memory

Perhaps nowhere has hypnosis engendered more controversy than over the issue
of "recovered" memory. Cognitive science has established that people are
fairly adept at discerning whether an event actually occurred or whether
they only imagined it. But under some circumstances, we falter. We can come
to believe (or can be led to believe) that something happened to us when, in
fact, it did not. One of the key cues humans appear to use in making the
distinction between reality and imagination is the experience of effort.
Apparently, at the time of encoding a memory, a "tag" cues us as to the
amount of effort we expended: if the event is tagged as having involved a
good deal of mental effort on our part, we tend to interpret it as something
we imagined. If it is tagged as having involved relatively little mental
effort, we tend to interpret it as something that actually happened to us.
Given that the calling card of hypnosis is precisely the feeling of
effortlessness, we can see why hypnotized people can so easily mistake an
imagined past event for something that happened long ago. Hence, something
that is merely imagined can become ingrained as an episode in our life
story.

A host of studies verify this effect. Readily hypnotized subjects, for
instance, can routinely be led to produce detailed and dramatic accounts of
their first few months of life even though those events did not in fact
occur and even though adults simply do not have the capacity to remember
early infancy. Similarly, when given suggestions to regress to childhood,
highly hypnotizable subjects behave in a roughly childlike manner, are often
quite emotional and may later insist that they were genuinely reliving
childhood. But research confirms that these responses are in no way
authentically childlike -- not in speech, behavior, emotion, perception,
vocabulary or thought patterns. These performances are no more childlike
than those of adults playacting as children. In short, nothing about
hypnosis enables a subject to transcend the fundamental nature and
limitations of human memory. It does not allow someone to exhume memories
that are decades old or to retrace or undo human development.

What It's Good For

So what are the medical benefits of hypnosis? A 1996 National Institutes of
Health technology assessment panel judged hypnosis to be an effective
intervention for alleviating pain from cancer and other chronic conditions.
Voluminous clinical studies also indicate that hypnosis can reduce the acute
pain experienced by patients undergoing burn-wound debridement, children
enduring bone marrow aspirations and women in labor. A meta-analysis
published in a recent special issue of the International Journal of Clinical
and Experimental Hypnosis, for example, found that hypnotic suggestions
relieved the pain of 75 percent of 933 subjects participating in 27
different experiments. The pain-relieving effect of hypnosis is often
substantial, and in a few cases the degree of relief matches or exceeds that
provided by morphine.

But the Society for Clinical and Experimental Hypnosis says that hypnosis
cannot, and should not, stand alone as the sole medical or psychological
intervention for any disorder. The reason is that anyone who can read a
script with some degree of expression can learn how to hypnotize someone. An
individual with a medical or psychological problem should first consult a
qualified health care provider for a diagnosis. Such a practitioner is in
the best position to decide with the patient whether hypnosis is indicated
and, if it is, how it might be incorporated into the individual's treatment.

Hypnosis can boost the effectiveness of psychotherapy for some conditions.
Another meta-analysis that examined the outcomes of people in 18 separate
studies found that patients who received cognitive behavioral therapy plus
hypnosis for disorders such as obesity, insomnia, anxiety and hypertension
showed greater improvement than 70 percent of the patients who received
psychotherapy alone. After publication of these findings, a task force of
the American Psychological Association validated hypnosis as an adjunct
procedure for the treatment of obesity. But the jury is still out on other
disorders with a behavioral component. Drug addiction and alcoholism do not
respond well to hypnosis, and the evidence for hypnosis as an aid in
quitting smoking is equivocal.

That said, there is strong, but not yet definitive, evidence that hypnosis
can be an effective component in the broader treatment of other conditions.
Listed in rough order of tractability by hypnosis, these include a subgroup
of asthmas; some dermatological disorders, including warts; irritable bowel
syndrome; hemophilia; and nausea associated with chemotherapy. The mechanism
by which hypnosis alleviates these disorders is unknown, and claims that
hypnosis increases immune function in any clinically important way are at
this time unsubstantiated.

More than 30 years ago Hilgard predicted that as knowledge about hypnosis
becomes more widespread in the scientific community, a process of
"domestication" will take place: researchers will use the technique more and
more often as a routine tool to study other topics of interest, such as
hallucination, pain and memory. He forecast that, thus grounded in science,
the clinical use of hypnosis would simply become a matter of course for some
patients with selected problems. Although we are not quite there today,
hypnosis has nonetheless come a long way from the swinging pocket watch.

------------

SCIENTIFIC AMERICAN GETS HYPNOTIZED
Our staff sees what it's like to "go under"

http://www.sciam.com:80/2001/0701issue/0701nashbox2.html

Here at Scientific American we pride ourselves on our skepticism toward
pseudoscience and on our hard-nosed insistence on solid research. So when we
invited Michael R. Nash of the University of Tennessee at Knoxville to write
the accompanying article on the scientific basis of hypnosis, we warned him
that we'd put him through the wringer -- which we did. But while editing the
article, we began to wonder: Isn't this something we should experience
ourselves? How many of us would be hypnotizable?

We invited Nash and research psychologist Grant Benham to New York so we
could see what hypnosis was like firsthand. Six editorial staffers -- three
men and three women, none of whom had been hypnotized before --were willing
to give it a try. What we found surprised us.

Nash and Benham set up two quiet offices for our initiation into hypnosis.
Each researcher hypnotized three people individually, spending about an hour
with each subject. They took us through the Stanford Hypnotic Susceptibility
Scales, which rate an individual's responsiveness from 0 to 12.

One of the most surprising things about our hypnotic experience was its very
banality. To induce hypnosis, Nash and Benham merely asked us to stare at a
yellow Post-It note on the wall and spoke to us in a calm voice about how
relaxed we were becoming and how our eyes were growing tired. "Your whole
body feels heavy -- heavier and heavier," they read from the Stanford
script. "You are beginning to feel drowsy -- drowsy and sleepy. More and
more drowsy and sleepy while your eyelids become heavier and heavier, more
and more tired and heavy." That soothing patter went on for roughly 15
minutes, after which all but one of us had closed his or her eyes without
being directly told to do so.

The Stanford scales consist of 12 different activities ranging from trying
to pull apart one's interlocked fingers and feeling one's elevated arm lower
involuntarily to hallucinating that one hears a buzzing fly. Of the six of
us, one scored an 8, one a 7, one a 6, two a 4 and one a 3. (A score of 0 to
4 is considered "low" hypnotizable; 5 to 7 is "medium" hypnotizable; 8 to 12
is "high" hypnotizable.) None of us accurately predicted how susceptible we
would be: some who thought themselves very suggestible turned out to be poor
subjects, and others who deemed themselves tough cases were surprised to
find their two outstretched arms coming together by themselves or their
mouth clamped shut so that they couldn't say their name.

We all had a sense of "watching" ourselves and were sometimes amused. "I
knew what my name was, but I couldn't think how to move my mouth," recalled
one staff member. Another said his fingers "felt stuck" during the
finger-lock exercise. "At first they pulled apart easily enough, but then
they seemed to sort of latch up. It was interesting to see that it was so
difficult."

Only one of us experienced item number 12 on the Stanford scale --
posthypnotic amnesia. In this exercise, the hypnotist tells the subject not
to remember what occurred during the session. "Every time I'd try to
remember," said the staff member who had this sensation, "the only thing
that came back to me was that I shouldn't remember. But when Dr. Benham said
it was okay to remember, it all came flooding back."

In general, the experience was much less eerie than we had expected. The
feeling was akin to falling into a light doze after you've awakened in the
morning but while you're still in bed. All of us found that we felt less
hypnotized during some parts of the session than during others, as if we had
come near the "surface" for a few moments and then slipped under again.

All in all, we concluded that seeing is believing when it comes to hypnosis.
Or maybe we should say hearing is believing: I'm the one who heard -- and
swatted -- the imaginary fly.

--Carol Ezzell, staff writer and a 7 on the Stanford scales

------------

WHAT DO YOU KNOW ABOUT HYPNOSIS?

http://www.sciam.com:80/2001/0701issue/0701nashbox3.html

IF YOU THINK...
It's all a matter of having a good imagination.
THE REALITY IS ...
Ability to imagine vividly is unrelated to hypnotizability.

IF YOU THINK...
Relaxation is an important feature of hypnosis.
THE REALITY IS ...
It's not. Hypnosis has been induced during vigorous exercise.

IF YOU THINK...
It's mostly just compliance.
THE REALITY IS ...
Many highly motivated subjects fail to experience hypnosis.

IF YOU THINK...
It's a matter of willful faking.
THE REALITY IS ...
Physiological responses indicate that hypnotized subjects are not lying.

IF YOU THINK...
It is dangerous.
THE REALITY IS ...
Standard hypnotic procedures are no more distressing than lectures.

IF YOU THINK...
It has something to do with a sleeplike state.
THE REALITY IS ...
It does not. Hypnotized subjects are fully awake.

IF YOU THINK...
Responding to hypnosis is like responding to a placebo.
THE REALITY IS ...
Placebo responsiveness and hypnotizability are not correlated.

IF YOU THINK...
People with certain types of personalities are likely to be hypnotizable.
THE REALITY IS ...
There are no substantial correlates with personality measures.

IF YOU THINK...
People who are hypnotized lose control of themselves.
THE REALITY IS ...
Subjects are perfectly capable of saying no or terminating hypnosis.

IF YOU THINK...
Hypnosis can enable people to "relive" the past.
THE REALITY IS ...
Age-regressed adults behave like adults playacting as children.

IF YOU THINK...
A person's responsiveness to hypnosis depends on the technique used and who
administers it.
THE REALITY IS ...
Neither is important under laboratory conditions. It is the subject's
capacity that is important.

IF YOU THINK...
When hypnotized, people can remember more accurately.
THE REALITY IS ...
Hypnosis may actually muddle the distinction between memory and fantasy and
may artificially inflate confidence.

IF YOU THINK...
Hypnotized people can be led to do acts that conflict with their values.
THE REALITY IS ...
Hypnotized subjects fully adhere to their usual moral standards.

IF YOU THINK...
Hypnotized people do not remember what happened during the session.
THE REALITY IS ...
Posthypnotic amnesia does not occur spontaneously.

IF YOU THINK...
Hypnosis can enable people to perform otherwise impossible feats of
strength, endurance, learning and sensory acuity.
THE REALITY IS ...
Performance following hypnotic suggestions for increased muscle strength,
learning and sensory acuity does not exceed what can be accomplished by
motivated subjects outside hypnosis.

------------

FURTHER INFORMATION:

HYPNOSIS FOR THE SERIOUSLY CURIOUS
Kenneth Bowers. W. W. Norton, 1983
http://www.amazon.com/exec/obidos/ASIN/0393953394/newheavenneweart

CONTEMPORARY HYPNOSIS RESEARCH
Erika Fromm and Michael R. Nash. Guilford Press, 1992
http://www.amazon.com/exec/obidos/ASIN/0898628938/newheavenneweart


RELATED LINKS:

For an introduction to the history of hypnosis and its modern-day uses,
visit the Web site of the Institute for the Study of Healthcare
Organizations and Transactions at:

http://www.institute-shot.com/hypnosis_and_health.htm

For information on hypnosis research and clinical applications, visit the
International Journal of Clinical and Experimental Hypnosis at:

http://www.sunsite.utk.edu/IJCEH

Video of an actual hypnosis session can be viewed at:

http://www.sciam.com/2001/0701issue/0701nashbox1.html


THE AUTHOR:

MICHAEL R. NASH is associate professor of psychology at the University of
Tennessee at Knoxville and is editor in chief of the International Journal
of Clinical and Experimental Hypnosis. He received his Ph.D. from Ohio
University in 1983 and completed his clinical internship at the Yale
University School of Medicine the same year. He has published two books, one
on the research foundations of hypnosis and the other on psychoanalysis,
both co-authored with Erika Fromm of the University of Chicago. He is the
author of more than 60 publications in scientific journals on the topics of
human memory, dissociative pathology, sex abuse, psychotherapy and hypnosis.
Nash has received numerous awards for his scientific and clinical writing.