Transcript CONSCIOUSNESS - ResourcdBlogs

States of Consciousness
HYPNOSIS
Discuss
• http://www.youtube.com/watch?v=prMvP9
ustN0
• What different states of consciousness do
you think there are?
• Of the time that you are awake , how much
time do you think you are consciously
thinking about the world around you?
• What do you think Hypnosis is ?
• What do you think happens to people who
are hypnotised?
Controversial Question
• When someone is hypnotised, do they enter a
different state of consciousness or is there another
explanation for their behaviour.
State versus Non-state
• State Theory: Hypnosis is a different state
from waking or sleeping
• Non-state: Hypnosis promotes relaxation,
imagination and compliance. So hypnotised
people are not in a different state, the just
behave differently
Hypnosis is a state of heightened
suggestibility in which people experience
imagined situations as if they were real.
Franz Anton Mesmer (17341815)
Mesmer developed a technique called
‘animal magnetism’ (later renamed
mesmerism).
Mesmer noticed that patients would often
enter a trance-like state. Apparent
‘miracle cures’ also resulted.
Eventually Mesmer realised the magnets
were unnecessary .
Hypnosis
• In 1841 Scottish surgeon James Braid witnessed a
demonstration of mesmerism and began to
develop his own technique.
• Braid held a bright object in front of patients’ eyes
while also making verbal suggestions.
• He argued mesmerism was a state of “nervous
sleep” produced by concentrated attention.
• He renamed it hypnosis after Hypnos, the Greek
god of sleep.
Hypnotic Induction Procedures
• Hypnotic induction is the process by which one
person leads another into hypnosis.
• It is not necessary to swing a watch in front of the
eyes or say “you are feeling sleepy”!
• Moss (1965) reported being able to sometimes
induce a trance simply by saying “Please sit in that
chair and go into hypnosis”!
Sample test items from the Stanford
Hypnotic Susceptibility Scale, Form C
Item
Suggested
Behaviour
Right arm will
become heavy
Criterion for
Passing
Arm lowered by at
least 6 inches
Moving hands
apart
Force is pushing
hands apart
Hands are 6 or
more inches apart
Mosquito
hallucination
Mosquito is
buzzing nearby
Any grimace or
acknowledgement
Posthypnotic
amnesia
Will not remember Three or fewer
suggestions
items recalled
Arm lowering
Hypnotic Susceptibility
• According to Hilgard (1977), in an average testing
session 10% of subjects will be completely
nonresponsive, 10% will pass all or nearly all
items, and the rest will fall in between. This is a
stable characteristic when tested 25 years later
people scored the same !
• However susceptibility can be enhanced by
increasing people’s expectations (Spanos et al.,
1991; Vickery & Kirsch, 1991).
Behaviour under Hypnosis
• http://www.youtube.com/watch?v=9djiWIWMaO
A
• Hypnotised people are very suggestible and their
behaviour will conform with what the hypnotist tells them.
Typical behaviour that can be induced include:
• Acting out imaginary scenes.
• Pretending to be an animal.
• Believing a limb cannot move or is insensitive to pain.
• Positive and negative hallucinations – seeing things that
are not really there, or not seeing objects that really are
present.
• Enhanced memory or posthypnotic amnesia
Plenary
• What is hypnosis?
• How can we be sure that hypnosis is real?
• What is a key argument against hypnosis
being a real phenomenon?
• Why do you think people vary in their
susceptibility to hypnosis?
• Why is hypnosis useful?
Test
• Define Hypnosis
• What is the only essential ingredient for
hypnotic induction?
• What is a key argument against hypnosis
being a specific state of consciousness?
• According to Hilgard what percentage of
people are not susceptible to hypnosis?
• What can increase susceptibility?
Why does hypnosis work?
• There are two main competing explanations
for how hypnosis works:
• Dissociation (state hypothesis) theories.
• Social Cognitive (non-state hypothesis)
theories.
Dissociation theories of hypnosis
• Dissociation theories view hypnosis as an altered
state of consciousness.
• Best known example is the neo-dissociation
theory proposed by Ernst Hilgard (1978, 1991).
• Hilgard argued that cognition involves multiple
systems of control which are not all conscious at
the same time.
• These systems are controlled and motivated by a
central ‘executive ego’.
Neo-dissociation Theory
• Executive ego
distributes cognitive
resources to different
tasks e.g driving and
using a mobile phone
!!! Multi-tasking
divides attention.
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Hilgard argued that during hypnosis the
hypnotist gains control of the executive ego, and
therefore has access to the various subsidiary
control systems.
Hypnosis creates a division of awareness in
which a person simultaneously experiences two
streams of consciousness (primary
consciousness and a hidden observer)that are
cut off from one another.
The primary consciousness responds to the
hypnotist’s suggestions, while the hidden
observer is stuck behind an amnesiac barrier,
aware of everything going on but unable to
communicate, until the hypnotist asks it to.
‘Hidden Observer’ Phenomenon
• In one study Hilgard (1977) hypnotised subjects
and suggested that they would not feel pain.
• Then placed arm in ice-cold water for 45 seconds
and reported level of pain experienced.
• For another group Hilgard said “Perhaps there is
another part of you that is more aware than your
hypnotised part. If so, would that part of you
report the amount of pain”.
‘Hidden Observer’ Study
(Hilgard, 1977)
14
12
10
Normal Pain
Hidden Observer
Hypnotized Subject
8
6
4
2
0
5
15
25
35
45
Hypnosis and Involuntary
Control
• When under hypnosis people subjectively
experience their actions to be involuntary.
• Can people be made to perform acts that are
harmful to themselves or others?
• Evans & Orne (1965) told hypnotized
subjects that a cup of foaming liquid was
‘acid’. They were told to throw it a person’s
face (to see if they would follow the
instructions despite it being harmful)
Evaluation
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However, a control group who were asked
to simply pretend that they were
hypnotised behaved in the same way.
This behaviour can be explained in terms
of “destructive obedience”; i.e.,
psychological compliance with an
authority figure (Milgram, 1974).
Evidence in favour of hypnosis being a separate state
of consciousness
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For some time now hypnosis has been successful when anaesthetics cannot be used
and in the treatment of chronic pain (Hilgard and Le Baron 1984).
People can imitate clinical depression successfully but that is not to say clinical
depression does not exist. The crucial point is that the hypnotised person believes
they are in a different state, whilst the imitator does not. (McIlveen 1995).
An important feature of the Hilgard model is the “hidden observer”. Hilgard (1973)
induced hypnotic deafness in a participant but also suggested that he should raise a
finger when asked if there was any part of him that could still hear. Deafness was
convincingly established but a finger was still raised when the question was asked.
In Hilgards view this is the hidden observer monitoring the situation and replying to
the question without the participants awareness.
Some researchers feel that hypnosis is associated with specific changes in brain
electrical activity (Crawford and Gruzlier – 1992)
It is possible we are looking at the wrong measures or the wrong part of the brain for
hypnotic phenomena.
Although Kosslyn et al (2000) found that when pps were asked to visualise adding
colour to a grey image there was increased brain activity in the left hemisphere when
they were hypnotised but not when they weren’t.
Plenary
• Can you describe Hilgard’s theory?
• What is the ‘hidden observer’?
• Use handout to identify criticisms of State
theories of hypnosis.
• Discuss
Test
• What is the proper name of Hilgard’s theory
of hypnosis?
• Briefly describe Hilgard’s evidence for the
hidden observer.
• What is Hilgard’s name for the part of
consciousness which is in control of the
multiple cognitive control structures?
• Why does hypnosis appear to produce
involuntary actions?
Social Cognitive theories of
hypnosis
• Social cognitive theories deny that hypnosis
produces an altered state of consciousness.
• Instead argue that hypnotic experiences result
from expectations of people motivated to take on
the role of being “hypnotised”.
• Subjects develop a perceptual set – a readiness to
respond to suggestions and to perceive hypnotic
experiences as real and involuntary.
Stanley Milgram (1933-1984)
Do we need to be hypnotised to
do things against our will?
I observed a mature and initially poised businessman
enter the laboratory smiling and confident. Within 20
minutes he was reduced to a twitching, stuttering wreck,
who was rapidly approaching nervous collapse. He
constantly pulled on his ear lobe, and twisted his hands.
At one point he pushed his fist into his forehead and
muttered “Oh God lets stop it”. And yet he continued to
respond to every word of the experimenter, and obeyed to
the end.
Milgram, Behavioral Study of Obedience
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In a study by Orne (1959) subjects were told
prior to being hypnotised that a common feature
of a trance is stiffening of the muscles in the
dominant hand.
This information was fictitious.
When the subjects were hypnotised, 55%
spontaneously displayed hand stiffening.
No subjects in a control group showed this
behaviour.
Social Cognitive theories do not claim that
hypnotised people are ‘pretending’. Expectations
can influence behaviour without conscious
awareness (e.g., placebo effects etc.)
•
Alternative explanations of hypnosis – Non-state
theories
Barber (1969) suggests that hypnosis is simply the result of experimental “demand
characteristics” i.e. the participant pleases the experimenter and tries not to “ruin the
show”.
• All hypnotic phenomena can be imitated by non hypnotised people, indistinguishably
from the hypnotised (Barber 1979)
In a study by Orne (1959) subjects were told prior to being hypnotised that a common
feature of a trance is stiffening of the muscles in the dominant hand.
This information was fictitious.
When the subjects were hypnotised, 55% spontaneously displayed hand stiffening.
No subjects in a control group showed this behaviour.
• No measure of brain activity successfully distinguishes between hypnotised and non
hypnotised states consistently. (Sarbin and Slagle 1972).
• Council and Kenny (1992) showed that expert ratings also failed to distinguish between
self reports of subjects experiencing hypnotic induction from those experiencing
relaxation training and they conclude that the state of consciousness produced by the
two procedures is indistinguishable.
• Wagstaff (1995) indicates that research and debate in hypnosis flourishes but we do not
seem to be any further forward in deciding whether there is an altered state of
consciousness we can call “hypnosis”.
Summary
• Hypnosis produces an increased receptiveness to
suggestions.
• Hypnotised people subjectively experience their
actions to be involuntary.
• Dissociation theories attribute this to divided
streams of consciousness.
• Social Cognitive theories attribute this to subject’s
expectation as to what effect hypnosis will have
on them.
Test
• What did Spanos et al find about
susceptability in hypnosis?
• What were the specific findings of Orne’s
study with the hand stiffening?
• What is a major weakness of state theories?
• Explain a problem with the argument that
hypnosis can be faked.
Evaluation and Analysis
Evaluation – However, Although, On the other
hand
• Look for alternative explanations for findings of
research or theoretical conclusions
• Criticise the research methods and validity of
findings
Analysis
• This suggests……
• This implies that………..
• This shows us that………….
Essay plan
• Describe what hypnosis is and how it
affects behaviour. Controversial question is
whether it produces an altered state of
consciousness or not.
• Outline and evaluate state theory including
3 pieces of research evidence
• Outline and evaluate non-state theory
including 3 pieces of research evidence
• Conclusion should discuss the usefulness of
hypnosis despite the inability of science to
explain the phenomenon completely.