International Handbook of Clinical Hypnosis - E-Lib FK UWKS

62 INTERNATIONAL HANDBOOK OF CLINICAL HYPNOSIS
space, only those studies of greater relevance to this clinical handbook of hypnosis
are addressed herein.The reader is referred to other reviews: Crawford, 1994a,b,
1996; Crawford & Gruzelier, 1992; Crawford, Horton, McClain-Furmanski &
Vendemia, 1998; Crawford, Knebel, Vendemia & Horton, 1999; Gruzelier, 1988;
Perlini & Spanos, 1991; Perlini, Spanos & Jones, 1996; Spiegel, 1991; and Spiegel
& Vermutten, 1994).While hypnotic susceptibility level is sometimes considered
irrelevant in a clinical context, it has been shown to be a highly relevant moderator
in many clinical and neurophysiological studies and is thus considered within the
chapter.It is hoped that knowledge of these neurophysiological ®ndings will help
the practicing clinician to communicate to the medical and psychological communities,
as well as to the patient and his/her family, as to how hypnosis works as an
important therapeutic technique in behavioral medicine and psychotherapy.
Furthermore, evidence presented herein supports hypnosis being an integral part in
the development of medical treatment plans for pain management.
NEUROPHYSIOLOGY OF THE HYPNOTIC STATE: IT TAKES
EFFORT TO BE HYPNOTIZED
Hypnosis involves an ampli®cation of focused attention either towards or away
from an internal or external event e.g., Hilgard, 1965, 1986; Krippner & Bindler,
1974).Since the nineteenth century hypnotically responsive persons commonly
report profound physical relaxation for exceptions, see BaÂnyai & Hilgard, 1976)
and alterations in perception following a hypnotic induction.In this physically
relaxed state, they report their experiences as being more involuntary and effortless
e.g., Bowers, 1982±83), yet, somewhat paradoxically, at the same time more
intense and involving than in a nonhypnotic condition.Such paradoxical reports
suggest a dissociation between awareness of attentional effort perceived workload)
and perceptual awarenesses.If we view hypnotizable persons as active and `creative
problem-solving agents' Lynn & Sivec, 1992) who can draw upon their abilities
including absorption, imagery, giving up of reality testing and focused and
sustained attention) during hypnosis, then the paradox is eliminated.Contrary to
common conceptions in the clinical and experimental literature, recent EEG and
cerebral metabolism research supports the view that hypnosis may take cognitive
effort that demands further allocations of attention and disattention Crawford,
1994a,b; Crawford & Gruzelier, 1992; Hilgard, 1986).
EEG DIFFERENCES BETWEEN LOW AND HIGHLY HYPNOTIZABLE
PERSONS
In studies of EEG brain wave activity, a robust ®nding is that theta power 3±7 Hz),
hypothesized to be associated with focused attention e.g., Schacter, 1977), is
positively related to hypnotic susceptibility e.g., Akpinar, Ulett & Itil, 1971;