STATE /NON STATE HYPNOSIS DEBATE RESEARCH
A core component of many theories of hypnosis is that it constitutes an 'altered state of consciousness' (ASC), qualitatively different from normal waking consciousness. Whether hypnosis produces an altered state of consciousness has been a debate central to academic study of hypnosis and has come to be known as the 'altered state debate'. Protagonists tend to be termed 'state' or 'non-state' depending on their theoretical orientation. State theorists hold that hypnosis is an altered state of consciousness whereas non-state theorists argue that the effects of suggestions can be experienced with or without the prior administration of a hypnotic induction and ask 'what is the necessity for an altered state?
One important factor to note when considering non-state theories is that they do not imply that subjects are always 'faking', or not truly experiencing a hypnotic response. Although non-state explanations use terms such as 'role enactment' or 'self-presentation' they are still entirely consistent with the notion that hypnotiezd participants have unusual experiences. One of the most eloquent defenses of this position comes from Spanos (1989):
"For instance, to describe a
man as enacting the role of "concerned husband" does not imply that
the man's displays of concern are necessarily feigned. By the same
token, the socio-cognitive view does not hold that hypnotic subjects
who report lessened pain following an analgesia suggestion must be
experiencing higher levels of pain than they report, or that those
who fail to report target items covered by an amnesia suggestion
must be privately rehearsing the very items they fail to divulge. On
the contrary, the socio-cognitive perspective attempts to account
for how, and under what circumstances, hypnotic subjects come to
convince themselves as well as others that they are unable to
remember, unable to bend their arms, and the like."
WHAT IS AN ALTERED STATE OF CONSCIOUSNESS ?
An altered state of consciousness is any which differs significantly from a normal or baseline state of consciousness. Some believe that key characteristics of a baseline state of consciousness include the psychological sense of the self at the centre of one's perception, and a sense that the self is identified with one's body. In contrast to this baseline state, Dietrich (2003) gives a description of a typical altered state of consciousness: "a sense of timelessness, denial of self, little if any self-reflection and analysis, little emotional content, little abstract thinking, no planning, and a sensation of unity".
One difficulty concerns how to assess a some of these concepts. Any aspect of brain function that we can measure changes continuously, a difficulty comes with deciding how much a measure would have to change from baseline to be considered 'altered'. And if consciousness is made up of multiple components, how many would have to be altered to constitute an overall alteration?
WHAT IS ESSENTIALLY HYPNOTIC ?
If we are attempting to determine whether hypnosis is an altered state of consciousness, or trying to find brain activity or some other marker which underpins hypnosis, we must be very clear about precisely what we mean by hypnosis.
NOT JUST RELAXATION - EVIDENCE FROM HYPNOTIC STUDIES
One confounding factor which we must account for is that of relaxation. Banyai & Hilgard (1976) published an experiment comparing two very different types of hypnotic induction. In one participants received a traditional induction, with suggestions for relaxation. In the second condition participants rode a stationary exercise bicycle. Both techniques were said to produce equivalent levels of suggestibility, and thus relaxation cannot be considered to be an essential component of hypnosis. The efficacy of the active-alert induction has subsequently been supported by Miller et al (1991) in a study comparing the efficacy of pain reduction suggestions following a traditional or active alert induction.
The 'classic suggestion effect' as described by Weitzenhoffer (1980) is that hypnotized individuals typically report that suggested effects seemed to happen effortlessly, or involuntarily. Whether the processes underlying suggestion really are effortless, or are just perceived as being effortless, is the matter of some debate (Ruehle & Zamansky, 1997), and is the key underlying point of contention between a number of theories of hypnosis.
Behavioural studies comparing the behaviour of hypnotised and unhypnotised subjects responding to suggestions have been the mainstay of 20th century research into 'state' effects. A number of interesting methodologies including the real-simulator design, have been developed to investigate hypnotic phenomenon. Interestingly it has been found that there is often very little difference in terms of response to suggestion between hypnotised and unhypnotised subjects - this has led some to conclude that the hypnotic 'state' is an irrelevance, while others believe that any response to suggestion falls within the domain of hypnosis.
Some recent studies are relevant to the state/non-state debate:
Gandhi et al (2005) - Would hypnosis by any other name smell as sweet? This study tested the effect of the same induction, labelled in different ways, upon suggestibility (measured with items from the Waterloo Stanford Group Scale of Hypnotic Susceptibility)
Raz et al (2006) - Tested the effect of the addition of a hypnotic induction upon a suggestion to reduce the Stroop effect. Concluded that the suggestive reduction of the Stroop inteference is accomplished regardless of whether hypnosis is induced.
Neuroimaging studies, which began with EEG and which have developed in to PET and fMRI methodologies, offer promise in discovering more about how response to suggestion is mediated by the brain. At least two clear methodological approaches have been used to tackle the issue. The first examines brain activity in individuals as they become hypnotiXed - this approach characteristics of the earler EEG studies. A later approach examines brain activity in response to tasks conducted in and outside hypnosis, the aim is to assess whether responses to suggestions are processed differently when in hypnosis - later ERP, PET and MRI studies have tended to take this approach. See Neuro-Imaging in the Research Section for more details.