1. Hypnosis a state of heightened suggestibility people experience imagined suggestions as if they were real.

3. Franz Anton Mesmer ( )
Austrian physician who developed technique ‘animal magnetism’
(later renamed mesmerism).
Noticed patients enter trance-like state. Apparent ‘miracle cures’
1841 Scottish surgeon James Braid witnessed mesmerism /developed own technique
Braid held bright object in front of patients’ eyes while making verbal suggestions
Renamed it hypnosis after Hypnos, Greek god of sleep.

4. Hypnotic Induction
Process by which one person leads another into hypnosis.
Not necessary to swing watch in front of eyes or say “you are feeling sleepy”!
The goal >to relax subject and increase attention
Essential feature of procedure is subject must realize they are being hypnotized
Not possible to be hypnotized against your will

5. Hypnotic Susceptibility Hilgard’s Hypnosis
According to Hilgard (1977), in average testing session
10% of subjects will be completely nonresponsive
10% will pass all or nearly all items
Rest will fall in between.
Susceptibility enhanced by increasing people’s expectations
(Spanos et al., 1991; Vickery & Kirsch, 1991).

6. Stanford Hypnotic Susceptibility Scale
Item
Suggested Behaviour
Criterion for Passing
Arm lowering
Right arm will become heavy
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 suggestions
Three or fewer items recalled

7. Behavior under Hypnosis
Hypnotized people are suggestible
Behavior will conform with what 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.

8. Posthypnotic suggestibility – subject given instructions under hypnosis and follows them after returning to non-hypnotized state
Posthypnotic amnesia – subject is instructed to not remember suggested behavior after leaving hypnotic state.
Brain under hypnosis

9. Hypnosis and changes in perception
Does hypnosis change person’s perception during positive and negative hallucinations?
Miller et al. (1973) tested hypothesis using Ponzo illusion

10. Via hypnotic suggestion participants told slanted lines ‘disappeared’
Subjectively they reported only seeing horizontal lines
They still reported upper line longer than lower
Shows visual system still processing sensory information
Effect of hypnosis solely on conscious awareness

11. 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 cup of foaming liquid was ‘acid’
Subjects could be induced to dip their hands in liquid and throw it in someone’s face

12. However, control group when asked to simply pretend they were hypnotized behaved in same way
This behaviour can be explained in terms of “destructive obedience”; i.e., psychological compliance with an authority figure
(Milgram, 1974)
No evidence that hypnosis has a unique power to coerce people against their will

13. Why does hypnosis work?
There are two main competing explanations for how hypnosis works:
Dissociation (state hypothesis) Theory
Social Cognitive (non-state hypothesis) Theory

14. Dissociation Theory An altered state of consciousness
Best known example is neo-dissociation theory proposed by Ernst Hilgard (1978)
Cognition involves multiple systems of control not all conscious at same time
These systems are controlled and motivated by central ‘executive ego’

15. Neo-dissociation Theory

16. Hilgard argued that during hypnosis, hypnotist gains control of executive ego, and has access to various subsidiary control systems
Hypnosis creates division of awareness/ person simultaneously experiences two streams of consciousness cut off from one another
One stream responds to hypnotist’s suggestions, while second stream remains “hidden observer” of everything that occurs

17. ‘Hidden Observer’ Phenomenon
Hilgard (1977) hypnotized subjects and suggested they would not feel pain
Placed arm in ice-cold water for 45 seconds and reported level of pain
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”.

18. ‘Hidden Observer’ Study (Hilgard, 1977)

19. Hilgard argued dissociation between streams of consciousness accounts for why hypnotism appears to produce involuntary actions
Subject intentionally carries out actions, but only ‘hidden observer’ is aware
Primary consciousness stream is cut off from this awareness and therefore action appears involuntary to subject
Show video of Experiment

20. PAIN IMAGINED, PAIN PERCEIVED: shows regions activated during physically induced pain (left), hypnotically induced pain (middle), and imagined pain (right). In contrast to physically and hypnotically induced pain, imagined condition provided minimal activation in anterior cingulated cortex, insula, and secondary somatosensory cortex. Activation in primary somatosensory cortex was observed only during hypnotically induced pain.
(S.W.G. Derbyshire et al., Neuroimage, 2004.)

21. Social Cognitive theory
Social cognitive theories deny that hypnosis produces an altered state of consciousness.
Instead hypnotic experiences result from expectations of people motivated to take on role of being “hypnotized”.
Subjects develop a perceptual set – readiness to respond to suggestions and to perceive hypnotic experiences as real and involuntary

22. Orne (1959) subjects told prior to being hypnotized that common feature of trance is stiffening of muscles in dominant hand
Information false
When subjects were hypnotized, 55% spontaneously displayed hand stiffening
No subjects in control group showed this behavior
Social Cognitive theory does not claim hypnotized people are ‘pretending’ Expectations can influence behavior without conscious awareness (e.g., placebo effects)

23. Hyper–suggestibility theorem
hypnotist's words are gradually accepted without subject’s censorship of what is being said.
Unhypnotized persons can also do this

24. Summary Hypnosis produces increased receptiveness to suggestions
Hypnotized people subjectively experience their actions to be involuntary.
Dissociation Theory attributes to divided streams of consciousness.
Social Cognitive theory attributes this to subject’s expectation as to what effect hypnosis will have on them

25. Hypnotherapy Wow! cessation of smoking (often in single session)
weight loss (body sculpting)
suppression of pain
hypnodontia – use of hypnosis in dentistry
enhance learning
reduce anxiety
Hypnodermatology - treating skin diseases with hypnosis.
“Self-hypnosis can be an alternative method of breast augmentation, preferable to surgical methods and certainly a lot easier, safer and less expensive.” advertisement
Wow!

26. What Hypnosis Won’t Do! Breast Enlargement Won’t tell any secrets!
Make You Dance the Funky Chicken
Unless you want to