• fl I?] AH EXPERIMENTAL STUDY OF AN HYPOTHETICAL MECHANISM OF SUGGESTION AND HYPNOSIS by William Nor sew or thy McB.ain A Thesis Submitted in Partial Fulfilment of the Requirements for the Degree of MASTER OF ARTS in the Department of PHILOSOPHY AND PSYCHOLOGY THE UNIVERSITY OF BRITISH COLUMBIA September, 1950, AN EXPERIMENTAL STUDY OP AN HYPOTHETICAL MECHANISM OF SUGGESTION AND HYPNOSIS Abstract The present study is designed to gather evidence con-? cerning two predictions made by Magda B. Arnold from her hypothesis as to the mechanism of hypnosis and aggestion. She believes this mechanism to be based upon ideo-motor action. As the individual imagines for, more precisely, images) the actions, situations, and, emotions suggested, this process tends to bring them about. A suggestion is not acted upon until the subject begins to think about it and to imagine the situation described in the suggestion. The results of three distinct kinds of operation have been referred to as resulting from suggestion. The Arnold hypothesis applies only to the ideo-mot or or 'prestige1 type, which is most typically represented .by the Hull Sway Test. It is held that sway occurs in the Hull test only as the subject imagines himself falling. Because imagery is essential to effective suggestion in both the waking and the hypnotic states, the prediction is made that a direct appeal to the subject to imagine himself falling will result in scores more closely related to his ability to become hypnotized than will the standard "you are fallings instructions. The latter are believed to be effective only to the degree that imagery accidentally results from them. A second prediction is that only those who can imagine most vividly and well will be capable of attaining the deepest states of hypnosis. For the purposes of this experiment score's obtained on the Friedlander and Sarbin Scale of Hypnotic Depth are taken as a measure of the 'hypnotizability' of the subjects, in the same manner as Hull Sway Test scores are used to indicate their relative 'suggestibility'. '!Goodness of imagery" is inferred from the scores of tests designed to be carried out in terms of the kinaesthetic and visual modes of imagery. Two groups of thirty students equated on sex, age, and sway in an initial sway test using Hull's standard "falling" instructions were subject to a second sway test. The second sway scores of the control group, which repeated the original test, correlated with the hypnosis scale scores to a degree significantly higher than did the first scores. The second sway scores of the experimental group, obtained from a test in which the instructions were to imagine falling as vividly as possible, showed a significantly smaller correlation than Hid the first ones. This is con• trary to Arnold's first prediction and is evidence towards rejecting the derived hypothesis. Using the scores of all sixty students a significant though moderate correlation was found between imagery test scores and the results of the hypnosis scale. This is in accord with the second prediction, and is evidence towards accepting the, derived hypothesis. The failure of a further analysis to show a significant relation to exist between scores of imagery and suggestibility suggests the interpretation that imagery scores represent a factor which is related to hypnotizability but independent of suggestibility. A more, adequate experimental control of motivation and the establishing of the reliability of the imagery tests used should precede the drawing of more definitive conclusions. ' ! ACMOWLBDGEMM TS This thesis results as much from the interest, criticism and assistance of faculty, staff and fellow-students, as from the efforts of the; writer. Such help is very gratefully acknowledged. In particular, thanks are due to Dr. D.C.G. MacKay, Dr. E.I. Signori and Prof. E.S.W. Belyea for guidance and criticism; to Prof. Belyea, Dr. J. Allardyce and Dr. F. X. Berry for apparatus loaned; to Dr. G.M. Shrum for making available a room for the experimental work; to Dr. G. A. Ferguson for advice on statistical procedures; to Miss I.I. Wilson for her generous views as to a typist's responsibilities; to Mr. Bruce Jaffary for his photographic work; to eighty most co• operative assistants for their interest; and to my wife, Elizabeth, for her forbearance. TABLE OF CONTENTS CHAPTER PAGE I INTRODUCTION AND STATEMENT OF THE PROBLEM 1. Introduction 1 2» The 'Sway? Hypothesis 4 3. The 'Imagery' Hypothesis 6 II HISTORICAL BACKGROUND OF TEE STUDY 1. Introduction 8 2. Suggestion aril Hypnotism 12 3. Suggestion 13 4. Ideo-motor Suggestion and the Sway Test 15 5. Ideo-motor Suggestion and Hypnotism 17 6. Imagery and the Ideormotor Response 21 III, THE EXPERIMENTAL APPROACH 1. Design of the Experiment 26. 2* The Surroundings 31 3. The subjects; 33 4, Test Components of the Experiment 37 5» The Sway Test (\i) Apparatus 38 (ii) Theoretical Considerations 43 (iii) Scoring 44 6. The Progressive Finger Tracing Test (i) Apparatus 48 (ii) Theoretical Considerations 51 (iii) Scoring 52 7. Memory: for Designs Test (i) Material Used 54 (ii) Theoretical Considerations 54 (iii) Scoring 56 8. The Paper Cutting Test (i) Materials 58 (ii) Theoretical Considerations 58 (iii) Scoring 60 9. Depth of Hypnosis Scale Mi) Apparatus 60 (ii) Discussion of the Scale 62 (iii) Scoring 64 2. TABLE OF CONTENTS OHAPTEH PAGE 17 ANALYSIS Of DATA 1. Introduction 67 2. Testing the 'Sway! Hypothesis 67 3. Comparison of Groups 68 4. Relation of Sway Test and Hypnotizability Scale Results 69 5. Testing of the 'Imagery1 Hypothesis 73 6» Relation of Imagery Test and Hypnotizability Scale Results 74 7. Suggestibility, Hypnotizability and Imagery 76 8. Summary of Analysis 80 V A CRITICAL EVALUATION 03? THE STUDY 1. Controls Believed to be Adequate 82 2. Inadequately Controlled Aspects 83 3. The Experimental Design 84 4. Additional Work Required 86 VI CONCLUSIONS 1. Interpretation 88 2. Summary 89 REFERENCES 91 APPENDIX A APPEDDIX B APPENDIX C LIST OF TABLES, PLATES, AND FIGURES TABLE PAGE I Comparison of Control and Experimental Groups 70 Correlations —• Sway Test and Hypnotizability Scores 72 III Correlations — Imagery Test and Hypnotizability Scores 74 IV Partial Correlation — Sway Test and Hypnot izabiiity Scores, Imagery scores 'partialed out! 78 Correlations - Sway Test and Hypnotizability Scores for Subjects matched on '2-test imagery! 79 PLATE PAGE I General view of Experimental Room and Apparatus 32 II Detection of Body Sway 39 III Recording Apparatus for Body Sway 40 IV Administration of Progressive Finger Tracing Test 49 V Administration of Depth, of Hypnosis Scale 61 FIGURE 1 !Flow Diagram' of Experimental Design 27 2 Sample Kymograph Record of Body Sway, Illustrating method of Scoring 45 3 Design and Dimensions of Progressive Finger Traeing Board 50 . 4 Designs used in Memory For Designs Test 55. CHAPTER I INTRODUCTION AMD STATEMENT OF THE PROBLEM Introduction Hypnosis as a phenomenon capable of being produced at will under conditions suitable for scientific observation, has been known since the last quarter of the eighteenth century. In more recent years, certain aspects of what has come to be known as 'suggestion! have become closely identified with hypnosis, and the evidence is strong that what difference exists between them is in degree rather than in kind. But. in spite of the long history of ttese allied phenomena, objective and verifiable facts concern• ing them are all too few. In 1933 Hull (28, p.18) remarked on the progress of knowledge concerning hypnotism: ''Almost nothing of significance has been accomplished during this period (the century following 1825) except the very gradual v correction of errors which originally flowed directly from bad experimental procedures." Hull was himself largely instrumental in stimulating a renewed interest in the experimental, as opposed to the clinical, approach to hypnotism, and much experimental work has been performed in the past twenty years. 2. Undoubtedly both the aura of mysticism and super• stition which has surrounded the subject, and the con• centration upon its clinical aspects, have retarded the accumulation of accurate knowledge concerning it. Even eager researchers are hesitant to entrust their professional reputations to a field in which there exists such a welter of half-proven, semi-disproyen, and contradictory "facts!. The exact scientific mind is appalled at the task of finding order and consistency in the experimental debris t which has accumulated about this subje ct in the last century and a half. The most serious deficiencies in experimental work concerned with hypnosis and suggestion probably have arisen from the lack of a theoretical framework into which results could be fitted, and from which essential controls might be inferred. Opinion, rather than fact, has too often been the starting point for investigation, and prestige, rather than knowledge, the goal. Experimentation based on such motives is not t oo concerned by the lack of an overall plan. In the interests of helping to, establish a systematic theoretical basis for the observed phenomena of hypnosis and suggestion, and giving direction and impetus to future work, Arnold (1) has put forward an hypothesis concerning the mechanism which she believes to be active in both 3 waking and hypnotic suggestion. It is designed to explain the "machinery of automatism'.' by which suggestions are trans• lated into action without the subjective experience of 'willing', and holds the ''goal directed activity" in which the subject engages when suggestion is brought to bear upon him is not rstriving to behave like a hypnotized person'1 as White (47) has stated, but "...striving to focus on the situation the experimenter describes and to imagine himself in it% Arnold believes that an understanding of this mechanism, which may almost be regarded as a psychosomatic process, will allow the experimenter to explain many of the apparent inconsistencies appearing in experimental work in this field.