Response to hypnotic suggestions is typically evaluated in terms of overt behavioral response, but the experience of hypnosis goes beyond publicly observable actions. In the classic instance, hypnotic behavior is accompanied by the subjective conviction that the suggested state of affairs is real, and by the experience of involuntariness in response -- the latter feature known as the classic suggestion effect. The experience of involuntariness has played an important part in theorizing about hypnosis, but it was not incorporated into standard instruments for measuring response to hypnosis, such as the Stanford and Harvard scales.
In our laboratory, we have used a couple of different involuntariness scales with the HGSHS:A, following up on the work of Patricia Gregg Bowers and her colleagues on the classic suggestion effect (International Journal of Clinical & Experimental Hypnosis, 1982, 1988).
One approach has been a simple 4-point Likert-type scale with labeled poles:
Deliberate, Effortful, Voluntary 1-----2-----3----4 Automatic, Effortless, Involuntary
In a large sample of subjects who received the HGSHS:A (N = 1269), total involuntariness score correlated r = .57 with total objective behavioral score (unpublished data).
Another approach has been a more complex 5-point categorical scale:
A. I did not respond at all during this time. (Score = 0)
B. My response was mostly voluntary. (Score = 1)
C. My response was mostly involuntary. (Score = 4)
D. The feeling that my response was voluntary was completely intermixed with the feeling that it was involuntary. (Score = 2)
E. At first my response was voluntary, but then later on it continued to occur involuntarily. (Score = 3)
F. None of the above. (Unscored)
In a large sample of subjects who received the HGSHS:A (N = 1924), total involuntariness correlated r = .65 with total objective behavioral score.
As of 2003, this categorical scale is the one we use in our own screening procedures, and it is the one included in the sample HGSHS:A response booklet provided elsewhere on this website.
For the next printing of the response booklet, however, we are considering possible changes to the involuntariness scale:
Eliminating Option F entirely, on the ground that the response is uninterpretable and does not enter into the scoring.
Reordering the options to create a perfect correspondence between the order in which they are listed and the scores they receive.
For the sake of symmetry, introducing a new option, "At first my response was involuntary, but then later on it continued to occur voluntarily", probably also assigned a score of 3.
Abandoning the categorical scale and reverting to the Likert-type scale, on grounds of convenience.
Shifting to an even simpler dichotomous rating scale, to correspond to the dichotomous nature of the objective behavioral and subjective success scores we also employ.
This page was last revised 02/17/06 02:21:30 PM.