The influence of time and gender on hungarian hypnotizability scores.

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The Influence of Time and Gender on Hungarian Hypnotizability 1

Scores

a

a

András Költő , Anna C. Gősi-Greguss , Katalin Varga

a

2 a

& Éva I. Bányai a

Eötvös Loránd University , Budapest , Hungary Published online: 20 Nov 2013.

To cite this article: András Költő , Anna C. Gősi-Greguss , Katalin Varga & Éva I. 2

Bányai (2014) The Influence of Time and Gender on Hungarian Hypnotizability Scores , International Journal of Clinical and Experimental Hypnosis, 62:1, 84-110, DOI: 10.1080/00207144.2013.841487

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Intl. Journal of Clinical and Experimental Hypnosis, 62(1): 84–110, 2014 Copyright © International Journal of Clinical and Experimental Hypnosis ISSN: 0020-7144 print / 1744-5183 online DOI: 10.1080/00207144.2013.841487

THE INFLUENCE OF TIME AND GENDER ON HUNGARIAN HYPNOTIZABILITY SCORES1 ˝ Anna C. Gosi-Greguss, ˝ András Költo, Katalin Varga, and Éva I. Bányai2


Eötvös Loránd University, Budapest, Hungary

Abstract: In a between-lab study, a constant and steady shift was found in hypnotizability scores measured with standard scales. To investigate a time effect in a Hungarian (within-lab) sample, 613 subjects’ scores on Stanford Hypnotic Susceptibility Scale, Forms A and B, 1898 subjects’ self-scores, and 1713 subjects’ observer-scores on the Harvard Group Scale of Hypnotic Susceptibility were analyzed. From the 1970s to 2010, a significant increase was observed in the SHSS:A and B scores of female subjects and the HGSHS:A scores of both genders. Females proved to be significantly more hypnotizable than males in a group setting but not in an individual context. Time and gender did not interact. The possible reasons for these effects on hypnotizability and the role of the testing context are discussed.

Hypnosis seems to have an effect on everybody, but people differ in how they react to it. Some report no remarkable change in their state under hypnosis, while others experience notable alterations of perception, thinking, action, and consciousness. Though the nature of the capacity to experience hypnosis is debated (e.g., Gorassini & Spanos, 1986; J. Hilgard, 1979; Laurence, Beaulieu-Prévost, & du Chéné, 2008; Wagstaff, 1991; Woody & Barnier, 2008), most authors agree that hypnotizability is a meaningful and valid construct. The hypnotizability scales developed in the late 1950s and early 1960s use a summative approach to measure hypnotic responsiveness: After a hypnotic induction, the hypnotist gives suggestions to the subject(s), covering different aspects and areas (domains) of hypnosis (E. R. Hilgard, 1973). The most widely used tools to measure hypnotic responsiveness are the individually administered Stanford Hypnotic Susceptibility Scales, Forms A, B, and C (SHSS:A, SHSS:B, and SHSS:C; Manuscript submitted October 22, 2012; final revision accepted November 1, 2012. 1 The authors thank Ildikó Zakariás and Gábor Füzér for the statistical consultations they provided and Anna L. Szirmai for her valuable comments on the article. 2 Address correspondence to András Költ˝ o, Doctoral School of Psychology and Department for Affective Psychology, Institute of Psychology, Eötvös Loránd University, Izabella utca 46, Pf. 755, Budapest, H-1384, Hungary. E-mail: [email protected] 84


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Weitzenhoffer & Hilgard, 1959, 1962). Based on the SHSS:A, a group method called the Harvard Group Scale of Hypnotic Susceptibility, Form A (HGSHS:A) was developed by Shor and Orne (1962, 1963). E. R. Hilgard (1978/1979) argued that behavioral measures of hypnotizability strongly correlate with every psychological feature supposed to be connected to hypnotic responsiveness. Therefore, the psychometrically validated standard scales of hypnotizability necessarily share some variance with most of the psychological attributes measured in hypnosis studies. Although the hypnotic susceptibility of the subjects shows a great variability measured by the standard hypnotizability scales, the hypnotizability of individuals seems to be very stable over time. Even over a 25-year period, test-retest correlation of SHSS:A scores was r = .71 (Piccione, Hilgard, & Zimbardo, 1989). Converging results of research conducted across the world strongly support hypnotic responsiveness being a universal trait. Why is it that, using the same standard method, one person is very susceptible to hypnosis while another might not respond to most hypnotic suggestions? The entire and consensual explanation is still missing. However, there are data showing that hypnotizability has a genetic component (Lichtenberg, BachnerMelman, Ebstein, & Crawford, 2004; Morgan, 1973; Raz, 2005; Szekely et al., 2010); subjects with low and high hypnotizability show morphometric differences in the size of the corpus callosum (Horton, Crawford, Harrington, & Downs, 2004) and exhibit several differences in neurophysiological processes as measured by EEG or fMRI (Barabasz & Barabasz, 2008; Oakley, 2008). In psychogenetic, neurophysiologic, and correlative studies of hypnotizability, the most commonly used (behavioral) measures of hypnotic susceptibility were SHSS:A, B, C and HGSHS:A. Extensive and worldwide use of the standard hypnotizability scales gave researchers the chance to aggregate the data collected since 1959. Aggregation can be done by gathering all hypnotizability data collected in a laboratory over a longer period of time (within-lab); another method is the meta-analytic examination of the studies across different laboratories using standard scales (between-lab), giving detailed statistical information on the results. The results of these methods may supplement each other. A methodological “loosening” might distort within-lab analysis (i.e., after a relatively strict adherence to the instructions of the standard hypnotizability scales, researchers may indulge in small infringements—see Benham, Smith, & Nash, 2002), while ecological validity of the results is enhanced by the fact that data are collected from several places throughout the world. In contrast, between-lab results represent just the local population, but researchers may be more consistent in adhering to standard administration.


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˝ ET AL. ANDRÁS KÖLTO

Studies where standard hypnotizability scales were administered and that were published before the mid-1990s revealed no significant gender differences. Sheehan and McConkey (1979), examining 1,944 subjects for the Australian norms of the HGSHS:A, found no difference, similar to McConkey, Barnier, Maccallum, and Bishop (1996), whose study included the hypnotizability data of 4,752 subjects collected over an 8-year period. These findings are consistent with the opinion of the leading theorists of hypnosis (e.g., E. R. Hilgard, 1986), namely, that male and female subjects’ hypnotizability do not differ significantly. Since the 2000s, two large-sample studies and a number of mediumsample-size papers reported gender differences in hypnotizability, all of them favoring females. Page and Green (2007) found a significant gender difference in the hypnotizability of 2,660 subjects examined over a 25-year period. Rudski, Marra, and Graham (2004) accumulated the results they collected administering HGSHS:A between 1971 and 1998. They found that there was a statistically significant difference between their male (n = 724, M = 6.34, SD = 2.81) and female (n = 1124, M = 6.81, SD = 2.82) subjects’ hypnotizability scores, in favor of females, t(205) = 3.474, p < .001. The authors analyzed the gender differences in the three canonical factors of the HGSHS:A items. Scores loading on ideomotor and cognitive-delusional factors showed no significant difference, whereas in the factor including challenge items, women scored higher than men, t(1871) = 4.937, p < .001. The effect size of this finding, however, was quite small (Cohen’s d = 0.167); the average HGSHS:A score of the females was less than 0.5 point higher than that of the males. Rudski and his colleagues note that the results may be caused by an artifact of item difficulty, because women scored higher than men in the items considered to be easier (in terms of passing percentage), but the result was not concordant with the difficulty rank of the items. Still, the validity of this result is supported by the findings of several standardization research projects conducted in the 2000s, where significant gender differences were found, even with much fewer subjects (N being between 100 and 200). Gender differences were reported in Danish (Zachariae, Sommerlund, & Molay, 1996), Italian (De Pascalis, Russo, & Marucci, 2000), Swedish (Bergman, Trenter, & Kallio, 2003), Israeli (Lichtenberg, 2008), and Polish (Siuta, 2010) studies. Rudski et al. (2004) argue that if the difference is not due to an artifact, it still may be attributable to the difficulty effect. Another possible explanation is that males and females may differ in some underlying personality variable that may in turn modulate HGSHS:A scores. They raise the example of reactance, in which men score higher than women. Benham et al. (2002) performed a keyword search on psychology databases and collected 87 research studies using the HGSHS:A,



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providing sufficient data for a meta-analysis. They found that since the beginning of the 1960s hypnotizability scores have been constantly increasing (the correlation between the average HGSHS:A scores and the year of its administration was r = .360, p < .001). They also analyzed studies administering the SHSS:C, yielding a correlation of r = .547 (p < .01) with 26 studies, which indicates that the increase in hypnosis scores was similar whether hypnosis was administered in individual or group contexts. They emphasized that the construct measured by the hypnotizability scales is complex and debated; still, they quoted Neisser, who stated about the IQ tests that “Standardized-test scores are all that we have, and they are certainly going up” (Neisser, 1997, as cited in Benham et al., 2002, p. 9). The authors suggest a number of possible explanations. Contextual differences, subtle changes in research methods (e.g., in recruitment, sampling, liberalizing the scoring criteria, even altering the standard text) might contribute to the increase, just like unnoted demographic changes in the composition of the samples. They also raise the point that theorists emphasizing the role of sociocognitive factors in hypnotic responding may explain the score shift with an overall increase in conformity; but a meta-analysis of Aschtype line judgment experiments (Bond & Smith, 1996) shows in fact a decrease rather than increase of sociocognitive factors. The more frequent appearance of hypnosis in the media may have changed attitudes toward hypnosis, which may be reflected in the increase of the scores. Changes in latent personality variables, as mentioned above, might also contribute. The last possibility Benham, Smith, and Nash raised was that due to children’s increasing exposure to a more and more complex and stimulating visual media including TV and video games (since the publication of their article we may also add the Internet and virtual worlds), they might surpass their elders in specific skills or mental sets. The neurophysiological studies they cite provide evidence that some of those changes may overlap. For instance, enhanced EEG theta activity was present during both video game play and in hypnosis sessions, which may reflect focused attention and ignorance of the competing stimuli: These characteristics are needed in both situations. The authors emphasized that the phenomenon may have a multicausal explanation and that the possible causes they had discussed were mainly speculative. They highlighted that the impact of changing contextual factors versus changing individual abilities could be better understood if more independent hypnosis laboratories examined their within-lab data in a similarly longitudinal fashion. Such an analysis was carried out by Woody and Sadler (2000), who aggregated HGSHS:A data over a period of 39 years. Somewhat surprisingly, their data showed a constant and significant decrease of hypnotizability over time. This result gives further motivation for other hypnosis laboratories to analyze their aggregated hypnotizability data.


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The Laboratory of Hypnosis Research at Eötvös Loránd University has been conducting research projects using standard hypnotic susceptibility scales since 1973. Since then, a large corpus of hypnotizability data has been aggregated. The SHSS:A and SHSS:B were first administered in the laboratory in 1973, followed by the HGSHS:A in early 1975 (Greguss, 1976; Greguss, Bányai, Mészáros, Csókay, & Gerber, 1975). Considering the findings in the literature mentioned above, we found it reasonable to analyze the effects of gender and time on the within-lab data we accumulated in the past 37 years. Based on previous findings and our observations, we hypothesize that (a) a slight increase can be expected in hypnotizability scores, both in individual and group settings, and (b) that sex-aggregated data will show a gender difference in favor of women. The fact that gender difference appeared just in the 1990s might reflect that the gap between male and female hypnotizability has been gradually increasing leads to (c) a scissors effect—an interaction between gender and time factors—may be present in hypnotic susceptibility. In addition, the previous between-lab findings can be compared to the observations of a single laboratory.

Method Recruitment and Sampling Process Since the early 1970s, both the individual hypnotic susceptibility scales (SHSS:A and B) and a group version (HGSHS:A) have been used regularly to prescreen subjects, to introduce hypnosis to undergraduate and postgraduate students, or to do research. In a great proportion of the cases, group hypnosis sessions took place in seminars and lectures for undergraduate psychology majors (“Introduction to Hypnosis,” “Methodology of Hypnosis Research,” and various special seminars on consciousness and/or hypnosis). In other cases, nonpsychology majors were recruited from universities of liberal arts, sciences, technology, medicine, and performing or visual arts. A third part of the sample included adults with various job experiences and ages. Some of the subjects were psychologists and medical doctors, being introduced to hypnotherapy. To the best of our knowledge, none of the subjects had been hypnotized before. Results of those who reported to have been hypnotized in any context were excluded from this analysis. As data were aggregated on a yearly basis, it caused a methodological dilemma: what to do with the years when just a few subjects were hypnotized. For instance, in 1981, only 9 male subjects took part in HGSHS:A testing, in two groups. One group, including 3 male subjects, consisted of students engaged in scientific work. The other group included 6 male medical doctors and psychologists who were



89

taking part in hypnotherapy training at the time. While the overall average HGSHS:A observer-score3 of male subjects—including those hypnotized in 1981—was M = 5.73 (N = 789), the mean score of the respective 9 men was M = 9.16. These subgroups were so specific (in terms of motivation and context) and included so few subjects that had they been included in the analysis, they would have seriously transgressed ecological validity as outliers. Therefore, we have decided to exclude scores of those years. SHSS:A and B scores were omitted if these scales were administered to less than 5 subjects in the given year. HGSHS:A scores were omitted if less than 10 subjects were hypnotized in the respective year. This restriction resulted in excluding 40 male and 22 female subjects from SHSS:A and B, 54 male and 17 female subjects from HGSHS:A (self-scoring), and 51 male and 24 female subjects from HGSHS:A (observer-scoring) from the final analysis. Participants In sum, 613 subjects (n = 176 male and n = 437 female) hypnotized in an individual setting were included in the analysis. Out of those hypnotized using the SHSS:A or B, 549 subjects provided information about their age. The mean age of the male and female subjects were 30.3 (SD = 11.95) and 33.2 (SD = 13.85) years, respectively. The youngest participant was 15; the oldest was 79 years old. The difference between male and female subjects’ age was not significant statistically (Z = −1.421, p = .155). As to the HGSHS:A, 1,898 subjects’ self-scores (n = 758 male and n = 1,140 female) and 1,713 scores registered by observers (n = 699 male and n = 1,014 female) were analyzed; 1,805 participants gave information about their age. The mean ages of the male and female participants were 25.3 (SD = 6.95) and 23.8 (SD = 6.08) years, respectively; age range was 16 to 68 years. Although females turned out to be statistically significantly younger, t(1803) = 4.741, p < .001, according to the literature (e.g., Morgan & Hilgard, 1973), the 1.5-year difference may not distort the results. Contrary to the majority of hypnosis research projects around the world, none of the subjects were given any money, credit, or other reward for participation; all of them took part in the testing on a voluntary basis. The possible impact of this methodological difference will be discussed below. We have to note that the HGSHS:A and SHSS:A, B were administered for partly different target groups. While the group testing served 3 In our laboratory, trained observers, who register and score the behavior of the hypnotized subjects, are present at most of the HGSHS:A hypnosis sessions. This is the score we refer to as “observer-score,” while subject’s self-reported rating is the “self-score.” Detailed information on the scoring is presented under “Procedure.”

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mainly education (giving experience of hypnosis to psychology undergraduates) or prescreening purposes, individual testing was applied mainly in a research context. This difference will be discussed under the “Significant Gender Difference in Group Setting but not in Individual Setting” section. Many hypnosis studies use smaller and more specific sampling. The large number and diversity of this sample cohort may increase the ecological validity of our findings. Procedure The Hungarian norms of the SHSS:A and B and the HGSHS:A have been published only in Hungarian so far (Greguss, 1976; Greguss et al., 1975). They are currently being prepared for publication in English as well. Detailed information on testing will be provided in those papers. Here we just note the following. The SHSS:A and B were administered orally by the authors and other licensed experts of hypnosis in a noise-dampened room in accordance with the standard instructions. The HGSHS:A was also administered orally, as per the standard instructions. In each session where the HGSHS:A was administered, another licensed hypnotist was also present. During most of the group hypnosis sessions, not only the subjects scored themselves in the standard response booklet (self-score) but trained observers also recorded how the subjects responded to the suggestions. Therefore, while all subjects have a self-score, the majority of the subjects also have an observerscore. Although these two measures show a high degree of convergence, Varga, Farkas, and Mér˝o (2012) point out that their constitution is somewhat different. While the self-scoring system reflects the perceptions of the self, the observer-score represents the visible behavior. In altered states of consciousness such as hypnosis, these two can differ to some extent. All of our research projects were carried out complying with the Professional Ethical Code of the Hungarian Psychological Association. Data Analysis We gathered all SHSS:A and B data into a single database and all HGSHS:A data into another. To decide if a time series or regression analysis should be carried out to measure the effect of time on hypnotizability scores, first Durbin-Watson tests of autocorrelation were conducted. Autocorrelation charts were built to check if there is any periodicity in the data. As no significant periodic pattern seemed to appear in the data, we used linear regression analysis to examine if hypnotizability scores showed any shift in time. Gender differences were analyzed using two-tailed Student’s t tests. If the Levene test of variance equality gave a significant result—showing that


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variances are not homogenous—we used the robust Mann-Whitney U test instead. In case of significant differences, effect size was also calculated. Interaction of time and gender effect was measured with a multiple linear regression analysis, using the enter method for model building. Analyses were carried out with SPSS 17.0 statistical program for Windows. The significance level for all analyses was set at .05, two-tailed.


Results SHSS:A and B scores, 1973–2010 Distribution of the SHSS:A and B scores—which are in line with previous findings—will be presented in a paper currently being prepared for publication about the Hungarian norms for the Stanford Hypnotic Susceptibility Scales. Also comparable with the results published in the literature, using Form A or B resulted in no significant difference of scores; 580 subjects were tested with the SHSS:A, with a mean score of 6.34 points (SD = 3.23), while 33 subjects were hypnotized with Form B, having a mean score of 7.36 points (SD = 3.46), t(611) = −1.760, p = .079. Table 1 shows the yearly average scores of the SHSS:A and B. Missing years indicate that in those years no data were collected, or the composite headcount of male and female subsample did not reach the previously set n > 5 criteria of inclusion; empty data rows indicate that in the given year less than 5 subjects from the respective gender were hypnotized. After breaking down hypnosis scores by year, autocorrelation was checked; then linear regression analyses were conducted for each gender separately. The Durbin-Watson statistic is 2.267 for males and 2.040 for females. If the value of the statistical test is between 2 and 4— for this sample size—it indicates that there is no autocorrelation within the data sequence (Veerbek, 2008). Autocorrelation charts suggested the same, with no autocorrelation coefficients reaching |r(ACF)| = .2. In Figure 1, the annual average scores of the combined SHSS:A and B can be seen for male and female subjects. The regression trend line for males is depicted with a solid line; the trend of female hypnotizability is marked with a broken line. Linear regression equities and adjusted R-squares are indicated. Linear regression statistics were calculated for each gender separately, using years as a regressor (1973 = 0, 1974 = 1, etc., through to 2010 = 37) and SHSS:A and B scores as dependent variables. As can be seen in Figure 1, hypnotic susceptibility scores seem to increase over time; male and female subjects’ trend lines seem to be slightly diverging. The question arises whether the difference of the shift is


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Table 1 SHSS:A and B: Yearly Average Scores (1973–2010)


Total Year

n

1973 1974 1975 1978 1979 1983 1984 1985 1987 1993 1994 1999 2000 2002 2003 2004 2005 2010 Total

Male

Female

Mean

SD

n

Mean

SD

n

Mean

SD

58 7 57 26 38 6 5 7 5 16 12 74 24 124 16 84 48 6

5.90 6.71 4.81 5.81 5.84 8.00 7.60 6.86 4.60 7.38 8.00 6.99 7.79 6.48 5.69 6.80 6.27 7.17

3.736 4.751 3.637 4.128 3.990 3.225 4.037 4.413 2.302 3.202 3.275 2.986 2.782 2.609 3.459 3.017 2.295 2.858

12 − 21 9 14 − − − − 7 − 19 6 38 5 25 20 −

6.00 − 5.00 6.89 5.64 − − − − 7.71 − 7.26 6.50 6.34 6.20 6.32 5.95 −

3.075 − 3.924 4.014 3.915 − − − − 4.348 − 3.724 2.345 2.694 4.494 3.351 2.460 −

46 7 36 17 24 6 5 7 5 9 12 55 18 86 11 59 28 6

5.87 6.71 4.69 5.24 5.96 8.00 7.60 6.86 4.60 7.11 8.00 6.89 8.22 6.55 5.45 7.00 6.50 7.17

3.919 4.751 3.512 4.191 4.112 3.225 4.037 4.413 2.302 2.205 3.275 2.719 2.840 2.583 3.110 2.871 2.186 2.858

613

6.40

3.251

176

6.24

3.333

437

6.46

3.219

statistically significant, that is, if there is a “scissors effect” in male and female hypnotizability. Male subjects’ regression is F(1, 174) = 1.509, p = .221, indicating that their hypnotizability has not shifted significantly over time. Adjusted R2 = .003: Time has barely any role in the variability of men’s hypnotic susceptibility measured in individual context. The regression of the females’ scores is F(1, 435) = 11.630, p < .0001, indicating that their hypnotizability scores have been increasing over the years. Adjusted R2 is .024: Time explains 2.4% of the variance of their scores. R2 for the overall model (without splitting the data by gender) is .018. HGSHS:A Scores, 1975–2010 Data of score distribution will be published in the standardization article, however it is comparable to previous findings. The correlation between self-scores and observer-scores is r = .828, p < .001. Tables 2 and 3 show the yearly average scores of HGSHS:A, based on self-scores and on observer-scores, respectively. Missing years indicate that no data were collected in those years or the composite headcount of the male and female subsamples did not

Figure 1.

Yearly average of scores on SHSS:A, B between 1973–2010 (N = 613), ∗ p = .001.


THE INFLUENCE OF TIME AND GENDER 93


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Table 2 HGSHS:A Yearly Average Scores (Self-Scoring), 1975–2010 Total


Year

n

Male

Female

Mean

SD

n

Mean

SD

n

Mean

SD

1975 1976 1977 1979 1980 1982 1983 1984 1985 1986 1987 1989 1990 1991 1992 1993 1994 1995 1996 2003 2004 2006 2007 2008 2009 2010

182 79 35 99 37 20 164 35 71 20 14 68 16 103 157 145 146 50 40 27 65 25 32 25 182 61

5.71 4.49 4.94 4.86 4.84 4.85 6.20 5.74 5.21 5.55 6.00 6.24 6.88 6.35 6.08 5.88 6.01 6.36 5.58 6.30 6.68 6.24 7.81 5.56 6.55 5.95

2.773 2.655 2.612 2.527 2.764 2.323 2.533 3.003 2.918 2.012 2.353 2.450 2.391 2.412 2.693 2.587 2.667 2.686 2.836 1.918 2.444 2.554 1.768 2.181 2.601 2.617

85 42 17 45 20 − 44 11 29 − − 30 − 43 76 70 70 24 18 − 18 − − 10 73 33

5.45 3.93 4.41 4.33 4.15 − 5.66 4.55 4.76 − − 6.20 − 6.09 5.75 5.33 5.81 5.67 4.56 − 6.94 − − 5.00 6.26 5.12

2.693 2.718 2.671 2.541 2.681 − 2.342 2.583 2.996 − − 2.483 − 2.477 2.866 2.696 2.747 3.060 2.791 − 2.838 − − 2.539 2.829 2.690

97 37 18 54 17 20 120 24 42 20 14 38 16 60 81 75 76 26 22 27 47 25 32 15 109 28

5.94 5.14 5.44 5.30 5.65 4.85 6.39 6.29 5.52 5.55 6.00 6.26 6.88 6.53 6.38 6.39 6.18 7.00 6.41 6.30 6.57 6.24 7.81 5.93 6.75 6.93

2.835 2.463 2.526 2.454 2.714 2.323 2.581 3.071 2.856 2.012 2.353 2.457 2.391 2.368 2.498 2.387 2.596 2.154 2.649 1.918 2.301 2.554 1.768 1.907 2.431 2.193

Total

1898

5.91

2.653

758

5.41

2.772

1140

6.25

2.518

reach the preset n > 10 criterion of inclusion; empty data rows indicate that less than 10 subjects from the respective gender were hypnotized in those years. Self-scoring. After data cleaning and grouping the hypnosis scores by year, autocorrelation was checked, and then linear regression analyses were conducted for each gender separately. The Durbin-Watson statistic was 1.932 for males and 1.974 for females. Although these values are slightly less than the canonical range of between 2 and 4, they are not substantially less than 2, suggesting that there is no autocorrelation within the data sequence (Veerbek, 2008). That finding is further supported by autocorrelation charts showing no autocorrelation coefficients exceeding |r(ACF)| = .2.


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Table 3 HGSHS:A, Yearly Average Scores (Observer-Scoring), 1975–2010


Total

Male

Female

Year

n

Mean

SD

n

Mean

SD

n

Mean

SD

1975 1976 1977 1979 1980 1982 1983 1984 1985 1986 1987 1989 1990 1991 1992 1993 1994 1995 1996 2004 2006 2007 2008 2009 2010

170 55 35 99 37 20 113 35 71 20 14 18 16 83 157 145 146 50 39 65 25 32 25 182 61

5.86 4.07 5.06 4.71 3.89 4.20 6.50 6.20 5.45 5.55 5.93 5.67 7.00 6.95 6.43 6.33 6.24 6.34 6.46 7.15 6.84 7.88 5.80 6.94 5.95

2.973 2.834 2.765 2.749 3.016 2.949 2.882 2.837 3.070 2.438 2.165 2.301 2.394 2.101 2.690 2.638 2.608 2.471 2.563 2.231 2.577 1.792 2.614 2.611 2.565

77 27 17 45 20 − 29 11 29 − − 18 − 34 76 70 70 24 18 18 − − 10 73 33

5.47 3.15 4.47 4.53 3.00 − 5.79 5.45 4.79 − − 5.67 − 6.79 6.16 5.87 5.87 5.54 5.67 7.17 − − 5.30 6.66 5.18

2.891 2.641 2.853 2.668 2.555 − 3.121 2.734 3.040 − − 2.301 − 2.129 2.921 2.787 2.745 2.519 2.590 2.307 − − 2.869 2.615 2.325

93 28 18 54 17 20 84 24 42 20 14 − 16 49 81 75 76 26 21 47 25 32 15 109 28

6.19 4.96 5.61 4.85 4.94 4.20 6.75 6.54 5.90 5.55 5.93 − 7.00 7.06 6.69 6.76 6.58 7.08 7.14 7.15 6.84 7.88 6.13 7.13 6.86

3.015 2.769 2.638 2.831 3.249 2.949 2.772 2.874 3.043 2.438 2.165 − 2.394 2.096 2.443 2.432 2.445 2.226 2.393 2.226 2.577 1.792 2.475 2.604 2.578

Total

1713

6.12

2.781

699

5.59

2.838

1014

6.48

2.682

Figure 2 shows the HGSHS:A self-scores in yearly breakdown. (Regression trend line for males: solid line; for females: broken line.) Linear regression equities and adjusted R2 s are marked. Data points show the mean of the hypnotizability scores in the respective years. The diagram shows a slight but definite shift in both genders’ hypnotizability. Trend lines show parallelism. Statistical analysis supports these findings. Linear regression statistics were calculated for each gender separately, using year as regressor (1975 = 0, 1976 = 1, etc., through to 2010 = 35) and the HGSHS:A self-score as dependent variable. Regression for males’ scores is F(1, 756) = 15.924, p < .0001, indicating that time influences their hypnotic susceptibility significantly. Adjusted R2 = .019: Time explains 1.9% variance of the

Figure 2.

Yearly average of self-scores on HGSHS:A between 1975–2010 (N = 1898), ∗∗ p < .0001.


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hypnotizability of males. Female subjects’ regression statistics show the same pattern: F(1, 1138) = 27.046, p < .0001, indicating a significant increase over time. Time explains 2.2% of the variation in the hypnotizability of females (adjusted R2 = .022). When analyzing regression without splitting the data by gender, time explained the 2.3% variance of the subjects’ hypnotizability scores (adj. R2 = .023). Observer-scoring. The same methods of analysis were used and a very similar pattern of results emerged as for the self-scores. After data cleaning and grouping hypnosis scores by year, autocorrelation was checked; linear regression analyses were then conducted for both genders separately. The Durbin-Watson statistic was 1.813 for males and 1.970 for females. These values almost reached the range between 2 and 4 conventionally accepted as the indicator of lacking autocorrelation. The autocorrelation charts revealed no autocorrelation coefficients exceeding |r(ACF)| = .2. In Figure 3, subjects’ observer-scores on the HGSHS:A are depicted in yearly breakdown. (Regression trend line for males: solid line; females: broken line.) Gender-respective linear regression equities and adjusted R2 s are marked. The diagram shows a moderate but still notable shift—slightly more rapid than in subjects’ self-scores—in the observer-scores of both genders. Trend lines seem to be parallel. Statistical analysis underscores these observations. Linear regression statistics were calculated for each gender separately, using years as regressor (1975 = 0, 1976 = 1, etc., through to 2010 = 35) and HGSHS:A observer-scores as dependent variable. Male subjects’ regression is F(1, 697) = 27.540, p < .0001, indicating that time has a significant effect on their hypnotic susceptibility. Adjusted R2 = .037: Time is accountable for the 3.7% variance of the hypnotizability of males. Female subjects’ regression statistics show the same pattern: F(1, 1102) = 40.307, p < .0001, indicating a significant shift over time. As adjusted R2 = .037, time explains 3.7% of female hypnotizability, too. The explanative power of time for the data not split by gender is adj. R2 = .039 (3.9%). Gender differences. The SHSS:A and B mean score of male subjects was M = 6.24 (SD = 3.33), whereas female subjects scored M = 6.46 (SD = 3.22). The 0.22 point difference is not significant statistically, t(611) = −0.762, p = .446. Male subjects reached an average HGSHS:A self-score of 5.59 (SD = 2.83); average score of female subjects was M = 6.48 (SD = 2.68). The difference of 0.89 point is statistically significant, Z = −6.471, p < .0001. Cohen’s d = −.322, indicating that the effect size is medium. The same difference was observed on HGSHS:A observer-scores with male subjects’ average score being 5.41 (SD = 2.77) and female subjects reaching

Figure 3.

Yearly average of observer-scores on HGSHS:A between 1975–2010 (N = 1713), ∗∗ p < .0001.


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6.25 (SD = 2.52), Z = −6.333, p < .0001. Cohen’s d = −0.317, indicating medium effect size. To check if gender enhances the explanative power of time on hypnotizability scores significantly, multiple regression models were built with hypnotizability scores being the dependent variables and time and gender the regressors, being added to the model using the enter method. R2 for the multiple model was .018, the same as overall linear regression of SHSS:A and B scores by time, which suggests that time and gender, controlled for each other, do not explain more variability of SHSS:A and B scores than time on its own. Gender adds some information to the variation of HGSHS:A scores. When it was entered into the model, it raised the variability of the subjects’ self-scores by 2.2% (R2 increased from .039 to .061); in addition to time, 2.1% variability of the observer-scores is explained by gender, shifting R2 from .023 to .044. Interaction of Time and Gender Effects Regression lines for the SHSS:A and B for the male and female subsamples seem to diverge slightly. To check the interaction between time and gender (what we referred to as scissors effect), a multiple regression model including an interaction parameter was built. For a better interpretation of the equations, time regressor was not the number of years but a centered4 series. The equation of the regression line is as follows: y = constant + β1 · (time) + β2 · gender + β3 · time ∗ gender interaction + e.

(1)

Regression of SHSS:A and B scores, using this multiple model, is F(3, 609) = 4.508 (p = .004). Adjusted R2 = .017. Although the regression equity is significant, interaction does not contribute to a remarkable extent (p = .465). Looking at Figure 1, it may be noted that there was a subtle divergence of the regression lines for male and female subjects’ SHSS:A and B scores (only females’ hypnotizability showed an increase over time). Statistically, however, the females’ scores did not increase faster than those of males. 4 Centering is a simple linear transformation where the mean of a data series is subtracted from each of the data points (Cohen, Cohen, West, & Aiken, 2003). In the present case, first the sum of the years when hypnotizability was tested was divided with the total sample size. The weighted average (approximately 1991) served as the mean of the years. Subtracting it from the series of the respective years resulted in 1991 being transformed into 0, while 1990 = −1, 1989 = −2, etc., through 1992 = 1, 1993 = 2, and so on. This procedure makes it easier to interpret the interaction parameter (centered time series∗ dummied gender variable).


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Multiple regression analyses for HGSHS:A self-scores and observerscores were conducted in the same way. As expected, both regressions turned out to be significant. For subjects’ self-scores, F(3, 1894) = 29.954, p < .0001. The interaction parameter did not contribute significantly (p = .902). Observer-scores revealed the same pattern: F(3, 1709) = 37.598, p < .0001. The interaction parameter had no effect on the regression (p = .779). HGSHS:A observer-scores and the self-scores of both genders rose significantly over time; the shift of male and female subjects were almost perfectly parallel. The addition of the interaction parameter to the regression equities did not result in any changes of the R2 s.

Discussion Slight Increase of Hypnotizability Scores, Except the SHSS Scores of Males Using linear regression analysis, the hypnotic responsiveness of our sample measured in individual settings (with SHSS:A and B) seems to increase over time among female subjects, whereas no significant shift of male subjects’ scores was observed. Although the increase is not significant statistically, the hypnotizability scores of males increased by 0.95 points between 1973 and 2010. Female hypnotizability scores increased by 1.6 points. R2 of the male regression being .003, time does not contribute to the variability of their hypnotizability scores, while 1.8% of females’ hypnotizability variance is explained by time. In a group context (HGSHS:A), hypnotizability scores seem to increase over time both in male and female subsamples and in selfand observer-scores as well. The overall increment of hypnotizability between 1975 and 2010 was around 1.2 points for self-scores and around 1.7 points for observer-scores. The R2 s of the respective regression equities indicate that time explains a 2% to 4% variance of the hypnotizability scores. These findings partly correspond with the observation of Benham and colleagues (2002) who found HGSHS:A scores—collected from many laboratories around the world—to constantly increase. In the 1960s, the mean HGSHS:A score of 10 studies was 5.99 (SD = 0.837); in the 1990s, the overall mean score of 23 studies was 6.73 (SD = 0.843). HGSHS:A scores, measured across labs, increased by 0.74 points in 4 decades. Although the shift is somewhat smaller than the change we observed, the pattern is nevertheless similar. Benham and his colleagues (2002) also meta-analyzed SHSS:C scores from the same period, finding a 1.32-point shift in individual scores. Our within-lab data of SHSS:A and B scores show almost the same extent of increase (the shift being significant for females but not for males). Although SHSS:C and SHSS:A and B scores



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cannot be directly compared to each other—the SHSS:C contains more cognitive-delusional suggestions, whereas the SHSS:A and B include mainly ideomotor and challenge items—the increase of scores seems to be general in all of the scales. That finding is consistent with the generally high correlation between SHSS:A and SHSS:C (e.g., Bowers, 1976, reported r = .82). What can be the reason behind the fact that in a group setting the hypnotizability scores of male and female subjects are increasing at the same pace, whereas no such parallelism was found in individual scores (and no significant increase in male hypnotizability scores)? A possible explanation is that the results are distorted by imbalanced gender subsamples. In the group setting, the proportion of male subjects in the total sample was 40%, whereas in the individual context it was even less, just 30%. If we compare Figure 1 with Figures 2 and 3, it can be seen that data points aggregating SHSS:A and B, especially those of males, are more scattered and sparse than those of the HGSHS:A. Yearly sample sizes also show a large fluctuation, from 5 to 10 to even more than 100 persons per gender per year. Maybe if more male subjects had been tested with the SHSS:A and B and more years had been represented in the analysis, males’ scores would have also shown a slightly increasing tendency. The fact that subjects taking part in SHSS:A and B testing were older (and more specifically selected) than those who underwent HGSHS:A testing may also be a contributing factor, although no analysis was carried out to examine if hypnotizability shows a gender difference across different age groups. This question needs further investigation. However, if the results are not attributable to sample distortions, they might partly be caused by different social and psychological mechanisms in how male and female subjects respond to hypnosis. This notion will be discussed below. Furthermore, a significant increase was observed in female SHSS:A and B scores and in both genders’ HGSHS:A scores. Because just a very few analyses of such aggregated within-lab data have been published so far, the best we can do is speculate on the possible explanations of our findings. First, we have to note that during the past decades various opportunities to experience altered states of consciousness (yoga, meditation, drugs, extreme sports, etc.) have become accessible to Hungarians. This may open up ways of trying and enjoying these states. The “alternate paths” hypothesis of hypnotizability by Josephine Hilgard (1979) predicts that trying these experiences may make people more open to hypnosis as well. Second, we argue that, while the intensive and frequent exposure to complex visual stimuli (e.g., television, Internet, video games, etc.)— what Benham and his colleagues (2002) suggest as a reason for the increase—might play an important role in the change of the SHSS:C scores, but it may not have much to do with the shift in HGSHS:A


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scores, since the HGSHS:A uses far less audiovisual stimuli than the SHSS:C. We rather speculate that the shift of the group scores may be more attributable to social psychological mechanisms. Although we do not have any direct evidence, it seems a feasible explanation that while current trends and changes in social environment do not have a notable effect on individual hypnosis sessions, subjects’ behavior may somehow reflect social “trends” when they are in a group; a possible mechanism might be the process of social comparison (Festinger, 1954). This could explain why SHSS:A and B scores are increasing at a slower pace among female subjects than are HGSHS:A scores and are not increasing significantly in male subjects, whereas the HGSHS:A scores of male and female subjects are increasing at the same rate. Szekely et al. (2010) in their psychogenetic investigation assumed that participants in group hypnosis sessions are characterized by a higher level of arousal than those hypnotized individually. That would lead to a different “optimization” of frontal dopamine metabolism, which can explain the differences in Cathecol-O-Methyltransferase (COMT) Val/Met genotypic polymorphism between subjects tested in group and individual contexts. Although Szekely and her colleagues emphasize cognitive efforts rather than social comparison as a stressor in group hypnotizability testing; their finding indirectly supports our notion that people react to group hypnosis differently than to individual hypnosis. This may even be true when the two methods—namely, HGSHS:A and SHSS:A and B—are functionally equivalent. According to the social-psychobiological theory of hypnosis (Bányai, 1991, 2008), the social psychological and psychogenetic mechanisms mentioned above determine the level of hypnotizability in an “interactive” way. In trying to interpret our results, we cannot avoid considering some historical and societal changes taking place in Hungary between 1973 and 2010. Relevant to our findings is the great shift in attitude toward hypnosis in public thinking. In the years of the communist regime (1948–1989), the discipline of psychology and the “mystic” (or indeed “occult”) phenomena of hypnosis were subjects of suspicion, even restriction or utter prohibition. Since the transition from communism to democracy, hypnosis gradually achieved high acceptance in the academic and clinical worlds (Bányai, 1991, 2008) and has become much better appreciated in public thinking. This sociocultural shift may have contributed to the slight increase in hypnotizability. We argue that the increase in hypnotizability may rather be connected to social psychological mechanisms than to changes in hypnotic “ability.” Phenomena and trends of the society may be reflected in a group setting where the subjects are exposed to observation and social comparison, whereas these differences may have less influence on individual testing. In the latter, only the subject and the hypnotist are present in a much more intimate situation than in group hypnosis. Therefore, in individual testing, the



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subject may feel less pressure to behave in a conformist way. This would also explain why the group hypnotizability scores are increasing faster than individual scores. While establishing rapport, both in individual and group hypnosis sessions, hypnotists initiate conversation about what kind of previous knowledge or expectations the subjects have about hypnosis. Subjects’ attitudes toward and expectations about hypnosis were analyzed in the early 1990s (for a summary of the findings, see Bányai, 2008). These results were not diachronic, just cross-sectional. Still, the investigation revealed that healthy subjects were motivated to take part in hypnosis research to have special, “altered” experiences. In their attitudes toward hypnosis, gender differences were found: Women expressed more ambivalence and fear and raised more questions than men did. In addition, the hypnotists also noticed an interesting change. In the 1970s and 1980s, more subjects made skeptical remarks prior to hypnosis (e.g., “I wonder if you will be able to hypnotize me”), whereas, in the 1990s and 2000s, more subjects reported that they were eager to try hypnosis to have new experiences and insights. In some cases, their attitudes towards hypnosis can even be described as “expecting a miracle.” This trend may be related to the changing public opinion about hypnosis in Hungary. It would have been interesting to merge the hypnotizability score data with data on other sociocultural changes in the society to see the correspondence with them, for example, happiness or subjective well-being. Inglehart, Foa, Peterson, and Welzel (2008) analyzed some of these trends based on data aggregated in the World Values Survey between 1981 and 2007. They observed that in most of the countries, increase of Gross Domestic Product per Capita (GDP) was strongly correlated with rising happiness and subjective well-being. The extent to which a society allows free choice to its citizens has a major role in happiness. This relationship, however, is not true for Hungary. Our country is one of the very few where transition from communism to a pluralistic democracy and an increasing GDP was not followed by the rise of happiness and subjective wellbeing. In fact, happiness and subjective well-being showed a significant decrease over time in Hungary between 1982 and 1999 (along with the sense of free choice). Inglehart and his colleagues supposed that a current investigation would show a relative recovery in happiness and subjective well-being. Unfortunately, the opposite pattern was found in other longitudinal surveys. For instance, whereas in 2002 13.5% of the Hungarian population suffered from clinical depression, a follow-up of the sample revealed that the proportion grew to 18% by 2006 (Kopp & Skrabski, 2006). From 1978 to 1993—in the most dynamic period of the transition—value preferences of the Hungarian society showed significant changes. The most important and remarkable of those were that


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the preference of “equality” and “compliance” (important values in the communist political system) decreased drastically and continuously, while preference of “affluence” and “happiness” (attributes of a capitalistic society) increased constantly and steadily (Füstös & Szakolczai, 1994). These findings may not be directly related to the trends we observed in hypnotizability scores, still they are in line with the slight though constant shift in HGSHS:A scores. This shift may partly be attributable to the phenomenon that more and more subjects come to the hypnosis laboratory to experience a “miracle.” Such expectations may have a lesser role in individual hypnosis sessions administered to older and more specifically selected subjects (see below), who were in a vis-à-vis interpersonal situation with the hypnotist. Compared to individual hypnosis, in group sessions—which include other participants and even observers—the subjects are exposed to public attention and social comparison that may lead the subjects to behave in a more situation-conformist way. Significant Gender Difference in Group but Not Individual Setting Our results revealed that there is an overall and significant gender difference of 0.9 points in HGSHS:A scores in favor of female subjects. Effect size is around −.3, indicating that it is medium sized. This result is comparable to Rudski et al.’s (2004) finding, whose within-lab investigation revealed a less than 0.5 point but significant difference in aggregated HGSHS:A points with an effect size of .167. Gender difference, however, was not significant when hypnotizability was measured individually with the SHSS:A and B; scores yielded a subtle 0.2-point difference. How can it be explained that women seemed to be slightly more hypnotizable than men in a group situation, while they showed almost the same extent of hypnotizability in individual settings? It is worthy of remark that in individually administered hypnosis sessions subjects were older than those in the group context. The cause of this difference is that in some of our experiments with SHSS:A and B, specific age groups were recruited (namely, older adults); with the HGSHS:A, the majority of the sample comprised university students and younger adults. This may discriminate between group and individual contexts. Participants may also have had different attitudes and expectations regarding individual and group hypnosis. As we pointed out above, the HGSHS:A sessions served mostly as an introduction to hypnosis or to prescreen subjects’ hypnotizability, whereas SHSS:A and B were applied in a research context. Selection mechanisms of SHSS sampling may have eliminated or masked gender differences, whereas such mechanisms were much less present in the HGSHS:A samples.



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Another explanation may be that males and females show different sex-type behaviors in group settings, whereas those differences do not occur in dyadic situations. Such a difference in cooperation was found by Charness and Rustichini (2011). In their social psychological experiment, behavior was significantly affected by the interaction of gender and setting: When being observed by their peers, males cooperated substantially less often, whereas females cooperated substantially more often than when they were not observed. The same underlying mechanism may also play a role in our findings. Maybe in the group setting males tend to be less cooperative while the females tend to be more so with the hypnotist than in an individual setting. That would also correspond with the differences in how time affects hypnotizability measured in individual versus group context: Group testing may generate more gender-related role expectations and more conformity. This possibility is currently being investigated by our research team, also taking into consideration the gender of the hypnotist and the archaic involvement of the subjects. Time and Gender Effect Do Not Seem to Be in Interaction Because gender differences in hypnotizability studies have been emerging only since the 1990s, we hypothesized that the phenomenon may be attributable to a scissors effect between the genders, meaning that female hypnotizability scores increase over time more rapidly than those of males. The results of the present study did not support our hypothesis. HGSHS:A observer-scores and self-scores have been increasing in an almost totally parallel way in both genders. In SHSS:A and B settings, female hypnotizability scores showed an upward shift, while the scores of male subjects did not increase significantly over time. However, when analyzing the trends with multiple regression analysis, the interaction proved to be insignificant. Therefore, our within-lab data do not support that time and gender influence hypnotizability in interaction with each other. Further Directions for Research Four conclusions of our findings deserve further investigation. Cardeña, Kallio, Terhune, Buratti, and Lööf (2007) highlight that in most—if not all—of the studies where a gender difference in hypnotizability was found, the hypnotist was male. Although in the current study we did not use the gender of the hypnotists as a classifying variable, it must be noted that the majority of the hypnosis sessions in our laboratory were conducted by female hypnotists. How the gender of the hypnotists and that of the subjects interact is currently being examined in our laboratory and should be published in the near future.


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The shift in hypnotizability scores in our Hungarian within-lab sample seems to be parallel with the meta-analytic between-lab findings of Benham and his colleagues (2002). This gives further support to the assumption that the increase of hypnotic susceptibility is a universal phenomenon. It would be interesting to see if other hypnosis laboratories in different parts of the world have also found such changes. It was mentioned above that, contrary to most hypnosis research projects, in our studies subjects did not receive any reward for their participation. Subjects have always come to our lab without receiving payment; hence, it seems that the motivation to participate in a hypnosis experiment may not only be material remuneration but also the novelty of the experience. We have to note that psychology is still treated with some suspicion but maybe also with greater curiosity in Hungary than in the United States where most hypnosis research projects are conducted. That notion also requires further sociocultural investigation. As we pointed out above, if data of such a long period are observed— collected over almost 4 decades—it seems rational to consider the long-term contextual changes that inevitably occur and form the sociological, political, and cultural aspects of society. In Hungary, the most important of these changes may be that the communist regime was replaced by a democratic and pluralistic political system in 1989. The transition has resulted in dynamic, short- and long-term changes in society (see the above cited findings on happiness, social well-being, depression, and value preferences). Certainly, the transition was continuous and gradual. Speculation as it may be, still, it seems reasonable that what we find in the lab may reflect these sociocultural changes. In that case, nonlinear regression could explain more variance of hypnotic susceptibility, regressed by time. Our preliminary finding is that using nonlinear regression methods slightly increases the explained proportion of the variability of hypnotizability. References Bányai, É. I. (1991). Toward a social-psychobiological model of hypnosis. In S. J. Lynn & J. W. Rhue (Eds.), Theories of hypnosis: Current models and perspectives (pp. 564–598). New York, NY: Guilford. Bányai, É. (2008). A hipnózis szociál-pszichobiológiai modellje [The socialpsychobiological model of hypnosis]. In É. Bányai & L. Benczúr (Eds.), A hipnózis és a hipnoterápia alapjai [The foundations of hypnosis and hypnotherapy] (pp. 379–445). Budapest, Hungary: ELTE Eötvös Kiadó. Barabasz, A. F., & Barabasz, M. (2008). Hypnosis and the brain. In M. R. Nash & A. J. Barnier (Eds.), The Oxford handbook of hypnosis: Theory, research and practice (pp. 337–364.). New York, NY: Oxford University Press. Benham, G., Smith, N., & Nash, M. R. (2002). Hypnotic susceptibility scales: Are the mean scores increasing? International Journal of Clinical and Experimental Hypnosis, 50, 5–16.



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Woody, E., & Sadler, P. (2000, July). Measuring and understanding individual differences in response to hypnotic suggestion. Paper presented at the 27th International Congress of Psychology, Stockholm. Zachariae, R., Sommerlund, B., & Molay, F. (1996). Danish norms for the Harvard Group Scale of Hypnotic Susceptibility, Form A. International Journal of Clinical and Experimental Hypnosis, 44, 140–152.


Der Einfluß von Zeit und Geschlecht auf Ungarische Hypnotisierbarkeitsskalen András Költo, ˝ Anna C. Gosi-Greguss, ˝ Katalin Varga und Éva I. Bányai Abstrakt: In dieser Studie wurde in Hypnotisierbarkeitsskalen, die mit Standardbewertungen gemessen werden, eine stetige Veränderung gefunden. Um in einer Ungarischen Auswahl den Zeiteffekt zu untersuchen, analysierten die Autoren die Stanford Hypnotic Susceptibility Skalen (SHSS:A und B)-Werte von 613 Probanden, 1898 Eigeneinschätzungen und 1713 subjektiven Beobachter-Skalen auf der Harvard Gruppen Skala der Hypnotischen Suszeptibilität (HGSHS:A). In den Jahren 1970 bis 2010 gab es eine signifikante Zunahme bei den SHSS-Ergebnissen der weiblichen Probanden und der HGSHS:A-Ergebnisse bei beiden Geschlechtern. Es konnte gesichert werden, daß Frauen innerhalb einer Gruppe hypnotisierbarer waren als Männer, nicht jedoch im individuellen Setting. Zeit und Geschlecht interagierten dabei untereinander nicht. Die möglichen Gründe dieser Effekte bezüglich der Hypnotisierbarkeit und der Rolle des Kontextes im individuellen Setting versus des Gruppensettings werden diskutiert. Stephanie Reigel, MD L’influence des variables temps et sexe sur les scores d’hypnotisabilité hongrois András Költo, ˝ Anna C. Gosi-Greguss, ˝ Katalin Varga et Éva I. Bányai Résumé: Cette étude a permis de découvrir un changement constant et régulier des scores d’hypnotisabilité mesurés à l’aide des échelles d’hypnotisabilité standards. Pour étudier l’effet du temps sur l’échantillon hongrois, les auteurs ont analysé les scores obtenus à l’échelle de susceptibilité hypnotique de Stanford (SHSS:A et B) de 613 sujets, ainsi que 1 898 scores résultant d’une autoévaluation et les scores de 1713 observateurs obtenus à l’échelle de susceptibilité hypnotique du Groupe de Harvard, formulaire A (HGSHS:A). Des années 1970 jusqu’à 2010, ils ont remarqué une augmentation significative des scores SHSS:A et B chez les femmes et des scores HGSHS chez les deux sexes. Les femmes se sont avérées significativement plus hypnotisables que les hommes au sein d’un groupe, mais non individuellement. On n’a pu déceler aucune relation entre les variables temps et sexe. Les raisons possibles de ces effets sur l’hypnotisabilité et le rôle du contexte individuel par rapport au contexte de groupe ont été abordées. Johanne Reynault C. Tr. (STIBC)

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La influencia de tiempo y sexo en las puntuaciones Húngaras de hipnotizabilidad András Költo, ˝ Anna C. Gosi-Greguss, ˝ Katalin Varga, y Éva I. Bányai Resumen: En este estudio se encontró un cambio constante y estable en las puntuaciones de habilidad hipnótica utilizando escalas estandarizadas. Para estudiar un efecto temporal en una muestra Húngara, los autores analizaron las puntuaciones en la Escala Stanford de Susceptibilidad Hipnótica (ESSH) de 613 sujetos y las autocalificaciones de 1898 sujetos y las puntuaciones de 1713 observadores en la Escala Grupal Harvard de Susceptibilidad Hipnótica (HGSHS). Desde los 1970s al 2010, hubo un incremento significativo en las puntuaciones en la ESSH de las mujeres y en las puntuaciones del HGSHS para ambos sexos. Las mujeres resultaron significativamente más hipnotizables que los hombres en el contexto grupal pero no en el individual. No hubo interacciones entre el tiempo y el sexo. Se discuten las posibles razones para estos efectos sobre la hipnotizabilidad y el rol del contexto grupal contra el individual. Omar Sánchez-Armáss Cappello, PhD Autonomous University of San Luis Potosi, Mexico

Do ethnicity and gender moderate the influence of posttraumatic stress disorder on time to smoking lapse?

The influence of gender on ICU admittance.

Prospective time estimation and hypnotizability in a simulator design.

Do the pictures influence scores on the Dartmouth COOP Charts?

Influence of age on the pharmacokinetics of alfentanil. Gender dependence.

The influence of gender on inheritance of exceptional longevity.

Voice onset time and speakers' age: data from Hungarian.

The influence of gender on heart rhythm disease.

Hypnotizability and dissociation.

[Gender Obesity Report--Influence of obesity on Reproduction and Pregnancy].

Infertility Specific Quality of Life and Gender Role Attitudes in German and Hungarian Involuntary Childless Couples.

Influence of menstrual cycle and gender on alprazolam pharmacokinetics.

The influence of time, temperature and packed cell on activated partial thromboplastin time and prothrombin time.

Hypnotizability testing and clinical hypnosis.

Hypnosis, hypnotizability, and placebo.

Hypnotizability and obesity.

Hypnotizability and phobic behavior.

Hallucination, dopamine and hypnotizability.

Couples and Miscarriage: The Influence of Gender and Reproductive Factors on the Impact of Miscarriage.

Depression: influence on time estimation and time experiments.

Brain Oscillations, Hypnosis, and Hypnotizability.

Hypnotizability and Performance on a Prism Adaptation Test.

Gender influence on specialists' ratings of residency program candidates.

Commentary on the influence of gender on the management of chronic pelvic pain.