State vs. non-state
The central theoretical disagreement regarding hypnosis is known as the "state versus non-state" debate. When Braid introduced the concept of hypnotism, he equivocated over the nature of the "state", sometimes describing it as a specific sleep-like neurological state comparable to animal hibernation or yogic meditation, while at other times he emphasized that hypnotism encompasses a number of different stages or states that are an extension of ordinary psychological and physiological processes. Overall, Braid appears to have moved from a more "special state" understanding of hypnotism toward a more complex "non-state" orientation. State theorists interpret the effects of hypnotism as due primarily to a specific, abnormal, and uniform psychological or physiological state of some description, often referred to as "hypnotic trance" or an "altered state of consciousness". Non-state theorists rejected the idea of hypnotic trance and interpret the effects of hypnotism as due to a combination of multiple task-specific factors derived from normal cognitive, behavioural, and social psychology, such as social role-perception and favorable motivation (
Sarbin), active imagination and positive cognitive set (
Barber), response expectancy (Kirsch), and the active use of task-specific subjective strategies (
Spanos). The personality psychologist Robert White is often cited as providing one of the first non-state definitions of hypnosis in a 1941 article: Put simply, it is often claimed that, whereas the older "special state" interpretation emphasizes the difference between hypnosis and ordinary psychological processes, the "non-state" interpretation emphasizes their similarity. Comparisons between hypnotised and non-hypnotised subjects suggest that, if a "hypnotic trance" does exist, it only accounts for a small proportion of the effects attributed to hypnotic suggestion, most of which can be replicated without hypnotic induction.
Hyper-suggestibility Braid can be taken to imply, in later writings, that hypnosis is largely a state of heightened suggestibility induced by expectation and focused attention. In particular,
Hippolyte Bernheim became known as the leading proponent of the "suggestion theory" of hypnosis, at one point going so far as to declare that there is no hypnotic state, only heightened suggestibility. There is a general consensus that heightened suggestibility is an essential characteristic of hypnosis. In 1933,
Clark L. Hull wrote:
Conditioned inhibition Ivan Pavlov stated that hypnotic suggestion provided the best example of a conditioned reflex response in human beings; i.e., that responses to suggestions were learned associations triggered by the words used: He also believed that hypnosis was a "partial sleep", meaning that a generalised inhibition of cortical functioning could be encouraged to spread throughout regions of the brain. He observed that the various degrees of hypnosis did not significantly differ physiologically from the waking state and hypnosis depended on insignificant changes of environmental stimuli. Pavlov also suggested that lower-brain-stem mechanisms were involved in hypnotic conditioning. Pavlov's ideas combined with those of his rival
Vladimir Bekhterev and became the basis of hypnotic psychotherapy in the Soviet Union, as documented in the writings of his follower K.I. Platonov. Soviet theories of hypnotism subsequently influenced the writings of Western behaviourally oriented hypnotherapists such as
Andrew Salter.
Neuropsychology Changes in brain activity have been found in some studies of highly responsive hypnotic subjects. These changes vary depending upon the type of suggestions being given. The state of light to medium hypnosis, where the body undergoes physical and mental relaxation, is associated with a pattern mostly of alpha waves. However, what these results indicate is unclear. They may indicate that suggestions genuinely produce changes in perception or experience that are not simply a result of imagination. However, in normal circumstances without hypnosis, the brain regions associated with motion detection are activated both when motion is seen and when motion is imagined, without any changes in the subjects' perception or experience. This may therefore indicate that highly suggestible hypnotic subjects are simply activating to a greater extent the areas of the brain used in imagination, without real perceptual changes. It is, however, premature to claim that hypnosis and meditation are mediated by similar brain systems and neural mechanisms. Another study has demonstrated that a colour hallucination suggestion given to subjects in hypnosis activated colour-processing regions of the occipital cortex. A 2004 review of research examining the
EEG laboratory work in this area concludes: Studies have shown an association of hypnosis with stronger theta-frequency activity as well as with changes to the
gamma-frequency activity.
Neuroimaging techniques have been used to investigate neural correlates of hypnosis. The induction phase of hypnosis may also affect the activity in brain regions that control
intention and process
conflict. Anna Gosline claims:
Dissociation Pierre Janet originally developed the idea of
dissociation of consciousness from his work with hysterical patients. He believed that hypnosis was an example of dissociation, whereby areas of an individual's behavioural control separate from ordinary awareness. Hypnosis would remove some control from the conscious mind, and the individual would respond with autonomic, reflexive behaviour. Weitzenhoffer describes hypnosis via this theory as "dissociation of awareness from the majority of sensory and even strictly neural events taking place."
Neodissociation Ernest Hilgard, who developed the "neodissociation" theory of hypnotism, hypothesised that hypnosis causes the subjects to divide their consciousness voluntarily. One part responds to the hypnotist while the other retains awareness of reality. Hilgard made subjects take an ice water bath. None mentioned the water being cold or feeling pain. Hilgard then asked the subjects to lift their index finger if they felt pain and 70% of the subjects lifted their index finger. This showed that, even though the subjects were listening to the suggestive hypnotist, they still sensed the water's temperature.
Social role-taking theory The main theorist who pioneered the influential role-taking theory of hypnotism was
Theodore Sarbin. Sarbin argued that hypnotic responses were motivated attempts to fulfill the socially constructed roles of hypnotic subjects. This has led to the misconception that hypnotic subjects are simply "faking". However, Sarbin emphasised the difference between faking, in which there is little subjective identification with the role in question, and role-taking, in which the subject not only acts externally in accord with the role but also subjectively identifies with it to some degree, acting, thinking, and feeling "as if" they are hypnotised. Sarbin drew analogies between role-taking in hypnosis and role-taking in other areas such as
method acting, mental illness, and shamanic possession, etc. This interpretation of hypnosis is particularly relevant to understanding stage hypnosis, in which there is clearly strong peer pressure to comply with a socially constructed role by performing accordingly on a theatrical stage. Hence, the
social constructionism and role-taking theory of hypnosis suggests that individuals are enacting (as opposed to merely
playing) a role and that really there is no such thing as a hypnotic trance. A socially constructed relationship is built depending on how much
rapport has been established between the "hypnotist" and the subject (see
Hawthorne effect,
Pygmalion effect, and
placebo effect). Psychologists such as
Robert Baker and Graham Wagstaff claim that what we call hypnosis is actually a form of learned social behaviour, a complex hybrid of social compliance, relaxation, and suggestibility that can account for many esoteric behavioural manifestations.
Cognitive-behavioural theory Barber, Spanos, and Chaves (1974) proposed a nonstate "cognitive-behavioural" theory of hypnosis, similar in some respects to Sarbin's social role-taking theory and building upon the earlier research of Barber. On this model, hypnosis is explained as an extension of ordinary psychological processes like imagination, relaxation, expectation, social compliance, etc. In particular, Barber argued that responses to hypnotic suggestions were mediated by a "positive cognitive set" consisting of positive expectations, attitudes, and motivation. Daniel Araoz subsequently coined the acronym "TEAM" to symbolise the subject's orientation to hypnosis in terms of "trust", "expectation", "attitude", and "motivation".
Information theory An approach loosely based on
information theory uses a brain-as-computer model. In adaptive systems,
feedback increases the
signal-to-noise ratio, which may converge towards a steady state. Increasing the signal-to-noise ratio enables messages to be more clearly received. The hypnotist's object is to use techniques to reduce interference and increase the receptability of specific messages (suggestions).
Systems theory Systems theory, in this context, may be regarded as an extension of Braid's original conceptualisation of hypnosis as involving "the brain and nervous system generally". Systems theory considers the
nervous system's organisation into interacting subsystems. Hypnotic phenomena thus involve not only increased or decreased activity of particular subsystems, but also their interaction. A central phenomenon in this regard is that of feedback loops, which suggest a mechanism for creating hypnotic phenomena.
Societies There is a huge range of societies in England who train individuals in hypnosis; however, one of the longest-standing organisations is the British Society of Clinical and Academic Hypnosis (BSCAH). It origins date back to 1952 when a group of dentists set up the 'British Society of Dental Hypnosis'. Shortly after, a group of sympathetic medical practitioners merged with this fast-evolving organisation to form 'The Dental and Medical Society for the Study of Hypnosis'; and, in 1968, after various statutory amendments had taken place, the 'British Society of Medical and Dental Hypnosis' (BSMDH) was formed. This society always had close links with the
Royal Society of Medicine and many of its members were involved in setting up a hypnosis section at this centre of medical research in London. And, in 1978, under the presidency of David Waxman, the Section of Medical and Dental Hypnosis was formed. A second society, the British Society of Experimental and Clinical Hypnosis (BSECH), was also set up a year before, in 1977, and this consisted of psychologists, doctors and dentists with an interest in hypnosis theory and practice. In 2007, the two societies merged to form the 'British Society of Clinical and Academic Hypnosis' (BSCAH). This society only trains health professionals and is interested in furthering research into clinical hypnosis. The
American Society of Clinical Hypnosis (ASCH) is unique among organisations for professionals using hypnosis because members must be licensed healthcare workers with graduate degrees. As an interdisciplinary organisation, ASCH not only provides a classroom to teach professionals how to use hypnosis as a tool in their practice, it provides professionals with a community of experts from different disciplines. The ASCH's missions statement is to provide and encourage education programs to further, in every ethical way, the knowledge, understanding, and application of hypnosis in health care; to encourage research and scientific publication in the field of hypnosis; to promote the further recognition and acceptance of hypnosis as an important tool in clinical health care and focus for scientific research; to cooperate with other professional societies that share mutual goals, ethics and interests; and to provide a professional community for those clinicians and researchers who use hypnosis in their work. The ASCH also publishes the
American Journal of Clinical Hypnosis. == History ==