Hemispheric Specificity and Hypnotizability: An Overview of Ongoing EEG Research in South Australia

  • C. Macleod-Morgan


At the 1979 I.S.H. Conference in Melbourne, it was reported (MacLeod-Morgan, 1979) that highly hypnotizable subjects show more specific lateralization during right and left hemisphere tasks than do low hypnotizables, using the change in alpha ratio when changing task, as the measure of specificity. The present paper is a resume of subsequent work, and included reports on:-
  1. (a)

    replication of the 1979 study;

  2. (b)

    four experiments showing that the specific lateralization of high hypnotizables does not appear to be disrupted by the presence of conflicting information during task performance; and

  3. (c)

    evidence (also using the hemispheric specificity paradigm) for regarding hypnosis as a right-hemisphere “task”.


The latter is discussed in relation to other theories of hypnosis.

Because of the constraints imposed by squeezing all the information I want to summarize into one small conference, paper, I will report only EEG findings. This means that I will not be referring at all to other aspects of the experiments mentioned, such as sex differences, or performance scores on the experimental tasks. I will also confine myself to dichotomized data, i.e. I will contrast highly

hypnotizable subjects (His) with low hypnotizables (LOs), rather than presenting any data as correlations using the complete range of hypnotizability scores.


Random Number Generation Conflict Task Hemispheric Specificity Hypnotic Susceptibility Random Number Generation Task 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.


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Copyright information

© Plenum Press, New York 1985

Authors and Affiliations

  • C. Macleod-Morgan
    • 1
  1. 1.Department of PsychologyUniversity of WyomingLaramieUSA

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