The use of observationally presented information to modify hypnotic susceptibility.

Examined the extent to which hypnotic susceptibility could be modified by means of various types of information modeled on a videotape. Of particular interest was the extent to which hypnotizability could be altered for the initially less susceptible S. 2 major informational components were compared: (a) behavioral modeling cues, in which Ss observed a model acquiesce to 7 hypnotic suggestions; and (b) verbal modeling cues, in which information was presented designed to correct misconceptions concerning hypnosis as well as provide concrete methods for experiencing hypnosis. 70 undergraduates completed the Stanford Hypnotic Susceptibility Scale (SHSS) Form B. After the manipulation period, Ss completed the SHSS Form C. Several days later, Ss completed M. Diamond's CP Scale of Hypnotic Susceptibility. Verbal modeling cues (in combination with motivational encouragement) were significantly more effective than the other cues, even for the initially less susceptible Ss. Results are discussed in relation to social learning and cognitive approaches to behavior change. (23 ref.) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Hypnotic responsivity, meditation, and laterality of eye movements.

43 male undergraduates who were self-defined as right-handed and as never having meditated were pretested on a number of person variables, and were given the Gordon Test of Visual Imagery Control, a revision of the Questionnaire Upon Mental Imagery, and the Harvard Group Scale of Hypnotic Susceptibility. The Ss then meditated for 8 sessions. Measures of hypnotic responsivity, meditating skill, imaginal abilities, and attitudes toward hypnosis loaded on a common factor that was labeled "sustained nonanalytic attending." Laterality of eye movement, however, failed to load on this factor. The implications for current theorizing concerning hypnosis and meditation are discussed. (19 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

The Computer-Assisted Hypnosis Scale: Standardization and norming of a computer-administered measure of hypnotic ability.

In a counterbalanced, within-subjects, repeated measures design, 130 participants were administered both the Computer-Assisted Hypnosis Scale (CAHS; C. D. Grant, 1993) and the Stanford Hypnotic Susceptibility Scale, Form C (SHSS:C; A. M. Weitzenhoffer & E. R. Hilgard, 1962). For each hypnotic procedure, responsiveness was assessed along three dimensions: behavioral (CAHS, SHSS:C), subjective depth (Field Depth Inventory; P. B. Field, 1965), and relational involvement (Archaic Involvement Measure; M. R. Nash & D. Spinler, 1989). The CAHS was shown to be a psychometrically sound instrument for measuring hypnotic ability. The various dimensions of CAHS hypnotic responsiveness were highly positively related, and the CAHS compared favorably with the SHSS:C across the three dimensions assessed. Results are discussed in terms of the theory and practice of clinical assessment, noting directions for future research. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Hypnotizability, daydreaming styles, imagery vividness, and absorption: A multidimensional study.

Examined the interrelationships between the following measures: hypnotic susceptibility (Stanford Hypnotic Susceptibility Scale, Forms A and C), imagery vividness (Vividness of Visual Imagery Questionnaire; VVIQ), involvement in everyday imaginative activities (Tellegen Absorption Scale; TAS), and daydreaming styles (28 scales of the Imaginal Processes Inventory). Ss were 56 university students and staff members. Factor analysis produced a factor characterized as a positively vivid and absorptive imagination style. Hypnotic susceptibility, VVIQ, TAS, and positive-affect daydreaming styles all loaded on this factor. Two other factors were a dysphoric daydreaming style and a lack-of-attentional-control style. Stepwise multiple regressions suggested that males and females exhibit different relationships between hypnotic susceptibility and predictor variables. Similar differences were found for the VVIQ and the TAS and their daydreaming-scale predictor variables. (39 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Behavioral predictions from hypnotic responsiveness scores when obtained with and without prior induction procedures.

Administered the Barber Suggestibility Scale (BSS) and the Stanford Hypnotic Susceptibility Scale, Form A (SHSS) to 80 high school students, half with imagination instructions and half with hypnotic induction instructions. The Stanford Profile Scale of Hypnotic Susceptibility, Form I (SPS), was subsequently administered to test the predictive effectiveness of the scales. The SPS has both different induction procedures and different item content from the BSS and the SHSS, which are very similar in their test-suggestion topics. Correlations with the SPS were much higher following prior testing under induction rather than imagination conditions, and induction conditions raised both objective and subjective scores above imagination conditions. Although both the BSS and the SHSS yielded similar results, some differences were noted. The subjective correction makes a greater difference for BSS than for SHSS scores, so that the subjective correction is to be recommended especially when the BSS is used. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Hypnotizability and the deployment of waking attention.

Although most theoretical accounts of hypnosis stress the contribution of attentional processes, such processes have not been considered extensively in past efforts to identify correlates of hypnotizability. A recently developed measure of waking attention deployment—the random-number generation task (RNG)—is described, and the relation between RNG scores and hypnotizability is presented. In 5 heterogeneous subgroups, 68 college-age Ss performed a 2-min RNG task and were administered the Harvard Group Scale of Hypnotic Susceptibility, Form A. 41 of these Ss later received the individually administered Stanford Hypnotic Susceptibility Scale, Form C (SHSS:C). Highly susceptible Ss (score of 8+ on each scale) demonstrated significantly better RNG performance than less susceptible Ss. This finding was replicated when using the SHSS:C as the measure of hypnotizability. Good randomizers scored an average of 2–3 points higher on both hypnotizability scales than poor randomizers. It is suggested that the process of deautomatization may be the common attentional mechanism that underlies hypnotizability and that is reflected in differential RNG performance. (23 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Suggestion and distraction in the control of pain: Test of two hypotheses.

96 18–30 yr old undergraduates, preselected for high or for low hypnotic susceptibility on the Harvard Group Scale of Hypnotic Susceptibility—Form A, reported their level of perceived pain during a 50-sec baseline immersion of their hand in ice water. In a 2nd immersion, independent groups of high and low hypnotizables (n?=?12) were tested (without hypnosis) under 4 conditions: analgesia suggestion alone, verbal-distraction task alone, a combination of suggestion plus distraction, and control. Among high hypnotizables, as compared to the control group, all 3 experimental treatments were effective in reducing pain. The combination of suggestion plus distraction was no more effective than was either of the single treatments alone in reducing pain. Among low hypnotizables, only the distraction treatment was effective. Results support an attentional-diversion explanation of the effect of waking analgesia suggestions rather than a special resources hypothesis. It appears that both high and low hypnotizables can divert attention toward external stimuli, but only high hypnotizables can successfully divert attention inward to control pain. (31 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Hypnotic susceptibility as related to gestalt closure tasks.

Studied the relationship of gestalt closure tasks to hypnotizability (Harvard Group Scale of Hypnotic Susceptibility and Stanford Hypnotic Susceptibility Scale) as a test of the hypothesis that the more highly hypnotizable do better on a task of holistic visuospatial functioning than those less responsive to hypnosis. Several other cognitive tasks were included. Four studies were conducted with 125 male and 106 female high school and college students. In Study I, high hypnotizables scored significantly higher than low hypnotizables on the gestalt closure tasks, but there were no significant correlations between hypnotizability and the other cognitive tasks. In Studies II and III, females showed significant correlations between hypnotic susceptibility and gestalt closure scores. In Study IV, a significant correlation between hypnotic susceptibility and gestalt closure was found for males. Results are consistent with studies of different types of cognitive functioning (hemispheric preference, creativity, attentional distribution, imaginative involvement, and absorption), all indicating differences in cognitive abilities associated with high hypnotizability. (33 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Enhanced visual memory during hypnosis as mediated by hypnotic responsiveness and cognitive strategies.

Investigated the hypothesis that hypnosis has an enhancing effect on imagery processing, as mediated by hypnotic responsiveness and cognitive strategies. Four experiments with 112 undergraduates compared performance of low and high, or low, medium, and high hypnotically responsive Ss in waking and hypnosis conditions on a successive visual memory discrimination task that required detecting differences between successively presented picture pairs in which 1 member of the pair was slightly altered. Results reveal that hypnotically responsive Ss showed enhanced performance during hypnosis, whereas nonresponsive Ss did not. Hypnotic responsiveness correlated with enhanced performance during hypnosis only. RT was not affected by hypnosis. Ss reported enhanced imagery vividness on the self-report Vividness of Visual Imagery Questionnaire during hypnosis. Two cognitive strategies appeared to mediate visual memory performance: (a) detail strategy, which involved the memorization and rehearsal of individual details for memory, and (b) holistic strategy, which involved looking at and remembering the whole picture with accompanying imagery. Both lows and highs reported similar detail-oriented strategies during waking; only highs shifted to a significantly more holistic strategy during hypnosis. (86 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Level of processing as a determinant of hypnotic hypermnesia.

Reconceptualized the distinction between those situations in which one can and cannot expect to observe hypnotic hypermnesia using the levels-of-processing theory of memory, as proposed by F. I. Craik and R. S. Lockhart (see record 1973-20189-001). In Study 1, 20 hypnotized Ss (high hypnotizables), relaxed/motivated Ss (high hypnotizables), and 20 simulating Ss (low hypnotizables) processed lists of words matched for meaningfulness and imagery value at "deep" or "shallow" levels. As predicted, the hypnotized group recalled more deeply but not more shallowly processed stimuli than the control groups. In Study 2, these findings were replicated with 30 undergraduates using improved experimental procedures and were extended to a recognition situation. In neither study was the observed hypnotic enhancement accompanied by an increment in errors. It is concluded that cognition at the time of processing is critical in rendering a stimulus amenable to hypnotic hypermnesia. (39 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Real and simulated occurrences of memory distortion in hypnosis.

79 undergraduates were prescreened for high or low susceptibility to hypnosis (Harvard Group Scale of Hypnotic Susceptibility—Form A) and tested individually to examine memory distortion in hypnosis. Independent groups of Ss were allocated to a 2?×?2 factorial design in which S grouping (hypnotic or simulating) was crossed with an information condition that either misled or did not mislead Ss about a series of scenes depicting an apparent robbery. It was hypothesized that memory distortion would characterize the performance of hypnotic Ss when memory was examined in unstructured, narrative recall. Results show that real Ss were differentiated appreciably from simulating Ss in the extent to which they incorrectly intruded uncued errors (i.e., errors not arising from misleading information) into their memories but not in their intrusion of cued errors (i.e., errors arising from misleading information). Real Ss remembered correctly more detail of a peripheral kind but also distorted more with respect to the same kind of detail. Results overall negate the view that earlier memory traces are revived in hypnosis, thereby leading to more accurate retrieval, and suggest that hypnotic Ss bring distinctive styles of information processing to bear on their recollections of complex, socially meaningful events. (28 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Day persons, night persons, and variability in hypnotic susceptibility.

Day persons (those most alert during daytime hours) and night persons participated in 2 experiments to examine within-S variability of scores over time on the Harvard Group Scale of Hypnotic Susceptibility—Form A, and the Stanford Hypnotic Susceptibility Scale—Form C. Regardless of scale used, day persons exhibited peak susceptibility at 10 AM and 2 PM; for night persons, peak susceptibility was found at 1 PM and between 6 PM and 9 PM. Furthermore, 2 peaks of temperature increase (1 PM and 6 PM) appeared to be associated with peaks in hypnotic susceptibility. However, such was shown to be associated with periods of food intake rather than with increases in hypnotic susceptibility. Results are examined with respect to methodological concerns and the potential existence of ultradian rhythms for hypnotic responsiveness. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Sustained attentional and disattentional abilities: Differences between low and highly hypnotizable persons.

Relations between sustained attentional and disattentional abilities and hypnotic susceptibility (Harvard Group Scale of Hypnotic Susceptibility: Form A; Stanford Hypnotic Susceptibility Scale: Form C) were examined in 38 low (0–3) and 39 highly (10–22) hypnotizable college students. Highs showed greater sustained attention on Necker cube and autokinetic movement tasks and self-reported greater absorption (Tellegen Absorption Scale) and extremely focused attentional (Differential Attentional Processes Inventory) styles. Hypnotizability was unrelated to dichotic selective attention (R. A. Karlin, 1979) and random number generation (C. Graham and F. J. Evans, 1977) tasks. Discriminant analysis correctly classified 74% of the lows and 69% of the highs. Results support H. J. Crawford and J. H. Gruzelier's (1992) neuropsychophysiological model of hypnosis that proposes that highly hypnotizable persons have a more efficient far frontolimbic sustained attentional and disattentional system. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Effects of hypnosis on P300 olfactory-evoked potential amplitudes.

From a sample of 93 undergraduates, 4 high- and 5 low-hypnotic-susceptibility (the Stanford Hypnotic Susceptibility Scale: Form C) Ss were exposed to a waking condition and a hypnotic induction condition that included a suggestion for anosmia. ANOVAs of the P300 showed significant amplitude increases for weak and strong odors for high-hypnotizable Ss in hypnosis, but not for high-hypnotizable Ss in the waking state. No such amplitude increases were found for the low-hypnotizable Ss. (13 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Aptitude for trance, task generalizability, and incongruity response in hypnosis.

Current theorizing about the process of "tolerance of logical incongruity" in hypnosis suggests that (a) aptitude for trance will be postively related to its occurrence, and (b) paradoxical behavior will manifest itself relatively consistently across different kinds of tasks presumed to measure the process. In a test of these predictions, 6 independent sets of 12 college students preselected for susceptibility to hypnosis (Harvard Group Scale of Hypnotic Susceptibility, Form A), were allocated to a 3 by 2 (Aptitude for Hypnosis by Instruction) factorial design. High-, medium-, and low-aptitude Ss were given either standard hypnotic or motivated waking imagination instructions, Ss being tested on 5 neutral (no incongruity) and 7 experimental items measuring incongruity. Results show that aptitude for trance determined incongruity response among both waking and hypnotic Ss, but that tolerance of incongruity could not reasonably be represented on currently accepted tests as a cognitive trait that exerts stable, enduring effects. (20 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Relation of some aspects of imagery and fantasy to hypnotic susceptibility.

Studied relations between hypnotic susceptibility and some aspects of imagery and fantasy in a normal population of 95 undergraduates. Vividness of imagery was assessed by a reliable questionnaire adapted from procedures 1st devised by G. H. Betts; dreams were collected by a diary method which studied the incidence of distortion in dream content; and hypnotizability was assessed by the Stanford Hypnotic Susceptibility scale (Form C), a standardized scale devised by the authors, and a rating procedure based on both scales. Results show a positive, curvilinear relationship between vividness of imagery and hypnotic susceptibility, but no significant relationship for fantasy. Evidence suggests that both imagery and fantasy, considered conjointly, lead to a more accurate prediction of deep susceptibility than the imagery variable alone. (34 ref.) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Posthypnotic amnesia as disrupted retrieval.

Investigated the process of remembering during posthypnotic amnesia by exploring the organization of recalled material in Ss displaying only partial amnesia. During 3 standardized hypnosis scales (Harvard Group Scale of Hypnotic Susceptibility and Forms B and C of the Stanford Hypnotic Susceptibility Scale) suggestions of posthypnotic amnesia were administered to 112 male undergraduates. Hypnotizable Ss tended to recall the scale items in random chronological order, compared to the relatively sequential recall of insusceptible Ss. The difference in temporal sequencing of recall during amnesia indicates that, for the hypnotizable S, posthypnotic amnesia is characterized primarily by a disruption or disorganization of part of the recall process, leaving other aspects of memory processing relatively unimpaired. Results suggest a resolution of the apparent paradox between the subjective reports of amnesic Ss and the objective evidence that the apparently forgotten memories remain available for other cognitive operations. (26 ref.) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Temporal organization of recall during posthypnotic amnesia.

Amnesia suggestions were administered to 35 undergraduates of low, medium, and high hypnotic susceptibility (the Stanford Scale of Hypnotic Susceptibility—Form C) who had learned a word list while hypnotized. The method encouraged Ss to organize the words sequentially. Organization of recall was measured on recall trials conducted before, during, and after suggested amnesia. Highly hypnotizable Ss showed a breakdown in temporal organization during amnesia, followed by a recovery of this organization after the suggestion was canceled. Results suggest that posthypnotic amnesia involves a disruption in the contextual relationships among memory items. Findings are discussed in the context of models that construe memory as a network of modes representing concepts and associative links between them. (41 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

A reexamination of the role of nonhypnotic suggestibility in hypnotic responding.

An alcohol-placebo paradigm was used to measure individual differences in the tendency to have directly suggested, as well as unsuggested, alterations in experience. Using the spectral analytic technique of C. G. Balthazard and E. Z. Woody (see record 1992-22396-001), such alterations in experience were found to be differentially correlated with the easiest items of the Harvard Group Scale of Hypnotic Susceptibility, Form A. The results indicated that easy hypnotic performances depend on some kind of social suggestibility not unique to hypnosis, and this factor becomes less important as the difficulty of the hypnotic performances increases. The results may also shed light on hypnotic sequelae, context effects, and two-component models of hypnotic performance. (PsycINFO Database Record (c) 2011 APA, all rights reserved)     

Comparative efficacy of behavioral training, training plus relaxation, and a sleep/trance hypnotic induction in increasing hypnotic susceptibility.

A social-learning-based behavioral training procedure and the same procedure with the addition of progressive relaxation instructions were compared with a traditional sleep/trance eye-fixation hypnotic induction; Ss were 45 adult volunteers who had completed the Standard Hypnotic Susceptibility Scale, Form C. As predicted, the hypothesis that a social-learning training procedure would be more effective than a sleep/trance induction was supported. The hypothesis that the addition of relaxation instructions would further potentiate the social-learning treatment was not supported. Results suggest that for Ss of low and medium hypnotic susceptibility, social-learning procedures are a more effective way of increasing suggestibility than a sleep/trance induction. Changes in Ss' conceptions of hypnosis, particularly in terms of moving toward a self-control viewpoint, are hypothesized to be an intervening variable. (48 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)