THEORIES OF HYPNOSIS:
WHAT MAKES IT WORK?
Why does Hypnosis work? This question has puzzled scientists for many decades. As with any scientific puzzle, numerous explanations have been advanced.
Physiological explanations have taken one of three main forms:
- Parasympathetic Nervous System Activation
- Brain-Wave Patterns
- Complex Interaction of both Brain Hemispheres
We will look at each of these briefly to better understand the life-altering phenomenon of Hypnosis.
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THEORY #3: Is It Dominant &
Non-Dominant Brain Hemispheres
The research on hemispheric function in Hypnosis are complex and the results are conflicting. In the past few years, several investigators have suggested that trance behavior is isomorphic with, and therefore presumably originates with, the abilities and behaviors of the right hemisphere of the brain. These investigators suggest that during Hypnosis the right hemisphere is more dominant than the left, while in waking states the left is more dominant.
While there is evidence that hemispheric activity patterns change in different states of Hypnosis, recent reviews and hypotheses about the functions of the brain suggest that the above view is oversimplified. Hence, it is concluded that it is probably a combined interaction of the dominant and nondominant brain hemispheres that is responsible for the successful results achieved in Hypnosis.
HOW DO ALL ASPECTS INTEGRATE?
Although the hemispheres are specialized for different aspects, complex brain function ultimately involves the integration of all aspects. Complex tasks involving rapid alteration between left and right hemispheric tasks show that hemispheric dominance can change dramatically in sequence with the tasks. For complex tasks, using both hemispheres provides results that are superior to those achieved by using either hemisphere alone.
Investigators have found that tasks that involve the hemispheres differentially (verbal vs. imagery tasks) tend to produce differences that are more marked in the Hypnotic state. In addition, evidence supports the notion that the functions of the two hemispheres are associated with the two different types of attention. S. J. Dimond (1979, “Performance by Split Brain Humans on Lateralized Vigilance Tests.” Cortex, 15, 43-50) suggested that the left hemisphere is active in selective attention, which is associated with fast habituation, and that the right hemisphere is involved in a state of more general vigilance, which habituates more slowly. Inhibition of the left hemisphere activity rather than increased right hemisphere activity may be a more accurate description of the EEG changes observed in Hypnosis.
DOES HYPNOSIS REQUIRE
MULTI-STAGE PROCESSING?
J. Gruzelier (1988, “The Neuropsychology of Hypnosis,” in M. Heap (ed.) Hypnosis: Current Clinical, Experimental and Forensic Practices, pp. 68-76, London: Croom Helm) has proposed a multistage process of brain function during Hypnosis. In the first stage of sustained focused attention, there is a relative increase in left hemisphere activity in susceptible subjects. The second stage of “letting go” involves a gradual inhibition of left hemisphere function. This is followed by an increase in right hemisphere activity in the third stage.
Taken together then, the research studies suggest that changes in lateralization of hemispheric activity do occur in Hypnosis. These studies further suggest that Hypnosis is not a unitary state but a reorganization of ongoing hemispheric and other cerebral relationships. The pattern of such changes depends both on the nature of the tasks and on differences in the way each individual interprets the context in which the task is performed.
SO, WHAT IS THE BOTTOM LINE?
CONCLUSION: Action involving both hemispheres of the brain can be traced to producing the results observed in Hypnosis. Hence, it can be concluded that much of the phenomena of deep hypnosis is both right- and left-hemispheric behavior, and the deeper the trance, the more likely the subject is to show complex behaviors of both hemispheres.
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Do you feel reassured and/or more balanced to know that the life-altering benefits of Hypnosis require the use and interaction of all of your brain resources? Can you feel a sense of awe and power at the magical way that the body possesses such phenomenal abilities? The body comes already equipped with all the vital capabilities necessary to create such astounding and valuable effects in our lives!
