Bornstein, Robert F. (1990). Critical importance of stimulus unawareness for the production of subliminal psychodynamic activation effects: A meta-analytic review. Journal of Clinical Psychology, 46, 201-210.
Performed meta-analysis that assessed the magnitude of behavior change produced by subliminal vs supraliminal drive-related stimuli (DRS) on 11 subliminal psychodynamic activation (SPA) studies (published 1966-1989) that employed both types of stimuli. The analysis revealed that subliminal presentation of DRS produced significantly stronger effects on behavior than supraliminal presentation of the same stimuli. Stimulus content, type of outcome measure, and S characteristics influenced the magnitude of subliminal/supraliminal response differences. Results support L. H. Silverman’s (1983) hypothesis that DRS must be presented subliminally to produce SPA effects.
Cikurel, Katia; Gruzelier, John (1990). The effect of an active-alert hypnotic induction on lateral asymmetry in haptic processing. British Journal of Experimental and Clinical Hypnosis, 7, 17-25.
In order to elucidate further left hemispherical inhibitory dynamics in response to instructions of hypnosis, bilateral haptic processing times were compared before and during a traditional hypnotic relaxation procedure and an active-alert procedure in which subjects pedaled a bicycle ergometer and instructions on mental alertness were incorporated with hypnosis. Previous evidence suggesting a slowing of left hemispherical processing and a facilitation of right hemispherical processing in susceptible subjects was replicated, and was shown to characterize high rather than medium susceptibles, the latter showing a bilateral slowing of processing. These effects occurred with both induction procedures whose influence on susceptibility was highly correlated. In fact the lateral shift in processing in the direction of left hemispherical inhibition and right hemispherical facilitation was favoured by the active-alert procedure, indicating that neuropsychological changes which occur with hypnosis cannot be discounted as a by-product of relaxation.
McLintock, T. T.; Aitken, H.; Downie, C. F.; Kenny, G. N. (1990). Postoperative analgesic requirements in patients exposed to positive intraoperative suggestions. British Medical Journal, 301 (6755), 788-790.
Sixty-three women undergoing elective abdominal hysterectomy were randomly assigned to a tape of positive suggestions or a blank tape during the operation. Anesthesia was standardized for all of the women. Postoperative analgesia
tape of positive suggestions or a blank tape during the operation. Anesthesia was standardized for all of the women. Postoperative analgesia was provided through a patient-controlled analgesia system for the first 24 hours. Pain scores were recorded every 6 hours. The outcome measures were morphine consumption in the first 24 hours and pain scores. Mean morphine requirements were 51.0 mg in women who were played positive suggestions, and 65.7 mg in those played a blank tape (p = 0.028). Pain scores were similar in the two groups. It was concluded that intraoperative suggestions seem to have a positive effect in reducing patients’ morphine requirements in the early postoperative period.
Wallace, Benjamin (1990). Hypnotizability and the modification of cognitive search strategies. International Journal of Clinical and Experimental Hypnosis, 38, 60-69.
An experiment was conducted to determine if Ss judged to be low in hypnotizability could be taught the efficient search strategies used by high hypnotizable Ss in the performance of a cognitive search task. Ss were requested to find objects embedded within a variety of pictorial scenes. High hypnotizable Ss were found to be more adept than low hypnotizables at finding more objects correctly. When low hypnotizable Ss were taught the efficient search strategies used by the high hypnotizables, their performance improved and was not significantly different from that of the high hypnnotizable Ss. Implications of these results for teaching search strategies are discussed.
Wallace, Benjamin (1990). Imagery vividness, hypnotic susceptibility, and the perception of fragmented stimuli. Journal of Personality and Social Psychology, 58, 354-359.
Two experiments were conducted to determine the role of hypnotic susceptibility level (high or low) and imaging ability (vivid or poor) in the performance of gestalt closure tasks. In Experiment 1, subjects were required to identify fragmented stimuli in the Closure Speed Test and in the Street Test. In Experiment 2, subjects reported on fragmented stimuli that were projected to the right eye and subsequently produced an afterimage. Individuals were asked to identify the composite if possible and to report on the duration of the afterimage. In both experiments, hypnotic susceptibility level and imaging ability affected reports of gestalt closure. The greatest number of correct closures was reported by those who were both high in hypnotic susceptibility and vivid in imaging ability. In addition, in the second experiment, this group also reported the longest enduring afterimage. These results are discussed in terms of the processes required to perform in a gestalt closure task.
Weinberger, Joel; Hardaway, Richard (1990). Separating science from myth in subliminal psychodynamic activation. Clinical Psychology Review, 10, 727-756.
This paper reviews subliminal psychodynamic activation (SPA). Eight common criticisms are described and evaluated: (a) SPA data analysis is too liberal; (b) there are enough nonsignificant unpublished SPA studies to offset those showing effects; (c) SPA studies are difficult to replicate; (d) the claims of SPA proponents rely on unpublished studies; (e) SPA stimuli are not really subliminal; (f) experimenter expectancy effects and/or demand characteristics can account for SPA effects; (g) the mediating events said to underlay SPA effects have never been evinced; and (h) alternative explanations for SPA effects are superior to the psychoanalytic ones typically offered. Theoretical and statistical analyses revealed that only the argument concerning mediating events has serious merit. The SPA stimulus for which the most support was found was Mommy and I Are One. Oedipal sanction stimuli were also found to yield reliable effects whereas Oedipal prohibition stimuli did not. Suggestions for future research are offered. Resistance to SPA findings are considered in Kuhnian terms.
typically offered. Theoretical and statistical analyses revealed that only the argument concerning mediating events has serious merit. The SPA stimulus for which the most support was found was Mommy and I Are One. Oedipal sanction stimuli were also found to yield reliable effects whereas Oedipal prohibition stimuli did not. Suggestions for future research are offered. Resistance to SPA findings are considered in Kuhnian terms.
Friswell, Rena; McConkey, Kevin M. (1989). Hypnotically induced mood. Cognition and Emotion, 3 (1), 1-26.
This article addresses theoretical and methodological issues that are central to an understanding of hypnotically induced mood. Initially, the hypnotic procedures that are typically used to induce moods are examined. Then the empirical research that has employed hypnotic moods is reviewed; specifically, the impact of hypnotic moods on physiological responses, behavioural performance, perceptual and cognitive responses, and personality, and clinical processes is examined. Finally, major theoretical and methodological issues are highlighted, and the research directions that will lead to a greater understanding of hypnotic mood are specified.
Hall, H.; Minnes, L. (1989). Psychological modulation of auditory responses. International Journal of Psychosomatics, 36 (1-4), 59-63.
Psychological modulation of auditory response, the effects of imagery and suggestion on auditory thresholds were examined in naive subjects. After a hypnosis-like induction, the subjects, who were not aware of the purpose of the study, were asked to generate and maintain a specific set of images before, during, and after which their auditory thresholds were tested. Following the imagery, which represented cooling and vasoconstriction in the cochlea, audiograms revealed a temporary auditory threshold shift (TTS) in the experimental group only. This TTS pattern was similar to that produced by exposure to loud noise. Information carried in the image is suggested as the basis for the observed auditory changes. Although a hypnosis-like induction was employed, the subjects’ level of hypnotizability did not appear to be related to the findings.
Kunzendorf, Robert G. (1989-90). Posthypnotic amnesia: Dissociation of self-concept or self-consciousness?. Imagination, Cognition and Personality, 9, 321-334.
Two studies of posthypnotic amnesia tested predictions derived from the ‘source’ monitoring theory of self-consciousness. Experiment 1 tested the prediction that posthypnotic source amnesia is irreversible, because hypnosis attenuates self- consciousness of whether one’s sensations have an imaginal source or a perceptual source. In this initial study, recall amnesia was reversed by posthypnotic cueing with a prearranged signal, but source amnesia was not reversed by such cueing. Experiment 2 examined whether the cued reversal of recall amnesia is attributable, in part, to the hypnotic attenuation of self-conscious ‘source monitoring’ and, in part, to the reversal of recall criteria: from a criterion rejecting ‘seemingly imaginary’ or ‘sourceless’ memories, to a criterion accepting ‘sourceless but familiar’ memories. In this latter study, posthypnotic recall amnesia was breached when subjects were instructed to trust their seemingly imaginary memories, but not when they were instructed to try harder to remember [emphasis removed from quoted text].
Litz, Brett T.; Keane, Terence M. (1989). Information processing in anxiety disorders: Application to the understanding of post-traumatic stress disorder. Clinical Psychology Review, 9, 243-257.
Several of the key defining features of PTSD are symptoms that reflect problems related to perception, attention, and memory processes (hypervigilance, flashbacks, nightmares, psychogenic amnesia, and concentration difficulties). Although there have been several recent attempts to explain such phenomena through facets of cognitive psychology, little empirical work has been completed to confirm or explicate such processes in PTSD. This paper critically reviews the theoretical and empirical work done to date in the area of information processing in anxiety disorders, so as to provide a context for future empirical work to identify the specific psychological mechanisms and controlling variables responsible for symptoms of PTSD. A working theoretical model of information processing variables in PTSD is also proposed to stimulate future research in this area.
Borgeat, Francois; Rezanowicz, Thaddeus; Chaloult, Louis (1988). La stimulation preconsciente et consciente de l’imaginaire erotique. Revue Canadienne de Psychiatrie, 33, 394-398.
The stimulation of erotic fantasies through the association of relaxation and erotic conscious or preconscious suggestions has been evaluated. This study was attempted following positive results in the stimulation of fantasmatic activity in alexithymic subjects with a similar procedure. Thirty female subjects, allocated into three groups practiced relaxation daily for two weeks including three sessions with psychological measures. During the second week, erotic suggestions, preconscious for one group and conscious for another one were added. The third group (control) received only relaxation throughout. Results have shown an increase of sexual arousal and erotic imagery during the sessions with erotic suggestions. Sexual activities and desire increased in the two experimental groups. There was no difference between the effects of the preconscious and conscious suggestions. Possible clinical applications of such a procedure are discussed.
Council, James R.; Loge, D. (1988). Suggestibility and confidence in false perceptions: A pilot study. British Journal of Experimental and Clinical Hypnosis, 5, 95-98.
Subjects received audiotaped instructions implying that they would perceive increases in odor or heaviness while comparing stimuli in a sensory-judgment task. Stimuli were actually indiscriminable. Subjects pretested as higher or lower in hypnotizability performed the task in either hypnotic or non-hypnotic conditions. In both treatments, greater hypnotizability was associated with more perceived changes in the stimuli and greater confidence in the reality of those perceptions. Results support a general factor underlying suggestibility in hypnotic and nonhypnotic situations. The findings are discussed in relationship to false confidence effects reported in hypermnesia research.
Fine, C. G. (1988). Thoughts on the cognitive perceptual substrates of multiple personality disorder. Dissociation, 1, 5-10.
Although MPD [multiple personality disorder] patients typically present to treatment with affective symptoms, trauma-related information is originally encoded in the patients’ perceptions and mediated by their cognitions. This paper describes the dysfunctional assumptive and perceptual categories that form the building blocks of MPD patients’ distorted experiences. Perceptual shifting techniques and cognitive reframing will consequently be the recommended interventions prior to therapeutic abreactive work
Jones, Lynette A. (1988). Motor illusions: What do they reveal about proprioception. Psychological Bulletin, 103 (1), 72-86.
Five illusions involving distortions in the perception of limb position, movement, and weight are described in the context of their contribution to understanding the sensory processes involved in proprioception. In particular, these illusions demonstrate that the position sense representation of the body and the awareness of limb movement results from the cross-calibration of visual and proprioceptive signals. Studies of the vibration illusion and phantom-limb phenomenon indicate that the perception of limb movement and position are encoded independently and can be dissociated. Postural aftereffects and the illusions of movement induced by vibration highlight the remarkable lability of this sense of limb position, which is a necessary feature for congruence between the spatial senses. Finally, I discuss the role of corollary discharges in the central processing of afferent information with respect to the size-weight and vibration illusions.
Sheehan, Peter W.; Donovan, Paul; MacLeod, Colin M. (1988). Strategy manipulation and the Stroop effect in hypnosis. Journal of Abnormal Psychology, 97, 455-460.
When asked to name the ink color of an incompatible color word (e.g., the word red printed in green ink), people show strong interference from the word. This study examined Stroop interference in subjects who were either high or low in susceptibility to hypnosis . Compared with performance in the waking state, the Stroop effect actually increased under hypnosis, a result particularly evident in the high- susceptible subjects. This contradicts the notion that high susceptibility subjects freely select appropriate strategies when hypnotized, a conclusion strengthened by an analysis of reported strategies in the two states. However, when provided with an attentional focusing instruction under hypnosis, high susceptibility subjects sharply reduced the Stroop effect, whereas low-susceptible subjects decreased it only slightly. One role of hypnosis may be to assist the subject in tuning attention, but only when an appropriate strategy is provided.
Wallace, Benjamin (1988). Hypnotic susceptibility, visual distraction, and reports of Necker cube apparent reversals. Journal of General Psychology, 115, 389-396.
Subjects, either susceptible (n = 50) or resistant (n = 50) to hypnotic suggestion, were asked to report on frequency of apparent reversals (ARs) to the Necker cube illusion. Such reports were made in the presence or absence of various types of visual, geometric surrounds (squares, triangles, crosses, or parallelograms). In agreement with a number of previous experiments, susceptible subjects reported perceiving more ARs than did resistant subjects. This difference held whether visual surrounds were present or absent. The presence of surrounds did serve to reduce AR reports regardless of hypnotic susceptibility level. The results are examined in terms of the ability of subjects to selectively attend when confronted with potential visual distractors.
AR reports regardless of hypnotic susceptibility level. The results are examined in terms of the ability of subjects to selectively attend when confronted with potential visual distractors.
Friedman, Howard; Taub, Harvey A.; Sturr, Joseph F.; Monty, Richard A. (1987). Visual information processing speed in hypnotized and nonhypnotized subjects. Journal of General Psychology, 114 (4), 363-372.
Using a backward-masking paradigm with a bias-free and ceiling-free psychophysical task, we tested hypnotized and control subjects for speed of visual information processing. Approximately half of each group received visual imagery suggestions in an attempt to influence attention. Imagery produced no significant differential effect. Although an absence of a hypnotizability-performance relationship was in keeping with findings of a previous study, those subjects in the present study who performed under hypnosis were, as a group, significantly superior to the other subjects in speed of information processing
Kihlstrom, John F. (1987). The cognitive unconscious. Science, 237, 1445-1452.
Contemporary research in cognitive psychology reveals the impact of nonconscious mental structures and processes on the individual’s conscious experience, thought, and action. Research on perceptual-cognitive and motoric skills indicates that they are automatized through experience, and thus rendered unconscious. In addition, research on subliminal perception, implicit memory, and hypnosis indicates that events can affect mental functions even though they cannot be consciously perceived or remembered. These findings suggest a tripartite division of the cognitive unconscious into truly unconscious mental processes operating on knowledge structures that may themselves be preconscious or subconscious.
Nash, Michael R.; Lynn, Steven Jay; Stanley, Scott; Carlson, Victor (1987). Subjectively complete hypnotic deafness and auditory priming. International Journal of Clinical and Experimental Hypnosis, 35 (1), 32-40.
The present study examined the cognitive and attentional mechanisms by which auditory information is maintained out of awareness during complete hypnotic deafness. Adopting a methodology from recent work on subliminally presented pattern- masked words and dichotic listening, the study tested whether spoken words presented during complete hypnotic deafness affect lexical decisions concerning subsequently presented word choices. The response of 9 hypnotized and 15 simulating Ss to spoken stimulus words presented following hypnotic deafness instructions was compared to the response of 20 baseline control Ss who never were exposed to the stimulus words. While the response pattern of hypnosis Ss appeared different from that of baseline control Ss, hypnotic Ss showed no evidence of the priming effect found in subliminal perception and dichotic listening studies. Simulator response deviated significantly from hypnotized and baseline control responses.
10 highs capable of hypnotic deafness, screened by Harvard Group and Stanford Profile Scales (Means 11.0 and 24.7, respectively) and 15 lows (means 1.7 and 1.7, respectively) participated in the study; the low hypnotizables being in the simulation group. For the experimental session, a different E administered a standard hypnotic induction and the deafness suggestion, testing for deafness by snapping fingers near S’s ear and making loud requests for motor responses.
a different E administered a standard hypnotic induction and the deafness suggestion, testing for deafness by snapping fingers near S’s ear and making loud requests for motor responses.
An experimental trial consisted of tapping an S on the hand, saying the stimulus word out loud, and visually presenting four words for the S to read out loud and circle one. “Of the 18 main experimental trials, the four-word array consisted of two words which were related to the stimulus (one word which was semantically related to the spoken stimulus word and one word which was phonetically related), and two neutral unrelated words” (p. 34). For example, if the spoken word were ‘dream,’ the word array might include ‘cream, tennis, sell, sleep.’ There also were “3 phonetically unrelated trials (whose arrays consisted of one phonetically related choice and 3 unrelated choices) and 2 stimulus word-unrelated trials (whose arrays consisted of the stimulus word and 3 unrelated choices) … [and] 7 dummy trials with 4 unrelated choices only” (p. 34). Ss rated their degree of deafness on a 10-point scale after hypnosis was terminated.
Possible sources of bias were examined by having 20 control Ss respond to blank tachistoscopic slides with the instructions that they were participating in a study of ‘subliminal perception.’ Another 22 Ss were asked to identify the semantically and phonetically related words from the word array, which for the most part they did successfully.
All Ss rated themselves as ’10’ on the deafness scale, indicating total deafness. The principal results are seen in Tables 1 and 2.
Table 1 Mean Number of Related and Unrelated Responses (Percentage of Responses) for all S Groups on the 18 Mean Experimental Trials
Response Category S Group N Related Unrelated Total
Hypnotized 9 7.22 10.78 18
(40.13%) (59.88$) (100%)
Simulating 15 12.13 5.87 18
(67.43%) (32.61%) (100%)
Baseline 19 8.79 9.21 18 Controls (48.82%) (51.17%) (100%)
Table 2 Mean Number of Phonetic and Semantic Responses within the Related Response Category on the 18 Main Experimental Trials
Related Responses S Group Phonetic Semantic Hypnotized 1.78 5.44
(9.89%) (30.24%) Simulating 7.07 5.07
(39.27%) (28.16%) Baseline 4.21 4.58 Controls (23.38%) (25.44%)
Hypnotized Ss were significantly different from simulators (Table 1) in number of related responses. Simulators gave significantly more related responses than baseline controls. Simulators also gave more phonetically related words than either the hypnotized or baseline Ss (Table 2); there was no difference between groups on semantically related words. (Authors performed other useful and detailed analyses.)
In their Discussion section, the authors note that they did not obtain the expected results of hypnotized Ss producing more related responses than baseline Ss. “In fact, internal analyses of hypnotized and baseline responses revealed that the pattern of choices for hypnotic deaf Ss was opposite to the direction predicted by subception. Hypnotic Ss appeared to avoid phonetically related word choices, even for items on which baseline control Ss scored above chance. …
“This kind of non-baseline performance by hypnotic Ss can be accounted for by either a strategic enactment conceptualization of hypnosis (Spanos, 1982; Wagstaff, 1981) or Hilgard’s (1979) neo-dissociation theory. Spanos might emphasize the hypnotic S’s active strivings to meet the hypnotist’s perceived expectations. … Neo-dissociation theory might stress the mechanisms by which processing of auditory inputs are maintained outside of awareness via a dissociative barrier.
” … Given the tendency for simulating Ss to ‘overplay’ hypnotic phenomena (Levitt & Chapman, 1979), one might have expected simulators to pointedly avoid related responses, thus producing a lower frequency of related words than either the hypnotic Ss or the baseline controls (in effect being more deaf than the deaf). Just the opposite occurred. One possible explanation for this behavior presents itself: In their work with posthypnotic suggestion and the ‘disappearing hypnotist’ … M. T. Orne and others found that simulating Ss may be more alert and responsive to demand cues than are hypnotic Ss. In the present study, the authors’ original hypothesis was that hypnotic Ss might reveal a subception effect by above-chance responding on related word choices. If we assume that this expectation was somehow communicated to Ss by some subtle aspect of the experimental procedure, then it is conceivable that simulating Ss were able to detect and act upon these cues, while hypnotized Ss remained relatively unattuned to such subtleties.
“In sum, the priming effect noted in the subliminal perception research does not appear to be a feature of complete hypnotic deafness, at least as measured in this study. The behavior of simulating Ss in the present study should be another caution to researchers that differences between hypnotized and simulating Ss may reflect simulation effects in addition to, or instead of, hypnotic effects” (pp. 37-38).
Popham, Coralee; Bowers, Kenneth (1987, October). A non-replication of the effects of hypnotizability and hypnosis on holistic processing. [Paper] Presented at the annual meeting of the Society for Clinical and Experimental Hypnosis, Los Angeles
This reports a non-replication of findings of Crawford & Allen’s work with Meir Memory for Pictures art task (retaining a picture in memory while comparing it to a second picture). Only highs got an increase in picture memory while hypnotized. Crawford attributed improvement during hypnosis to holistic processing. This study replicates and extends Crawford, using her task and a second task to assess whether the underlying process is holistic processing (using a Gestalt test they developed). The test involved an incoherent Gestalt produced by rotating parts of a coherent Gestalt. (Ss were required to select the coherent one, and to make a forced choice if they couldn’t identify which was correct).
Research Design 1. measured the number correct and percent of unsolved Gestalts correctly selected (Guiding Index) 2. Items were in 2 subsets (40 and 35 items) so Ss could be used as their own controls 3. 48 Ss were screened with the Harvard and then the Waterloo Group Scale form C
Pretest: 1. Waterloo – no effect of hypnosis ability on solving Gestalts 2. Waking condition – when Ss don’t know hypnosis is relevant, highs don’t do better 3. Lows in Waking condition do better
Posttest: 1. The second subtest of 35 pictures was more reliable than the first used above in the pretest. 2. There was no increase from baseline to posttest on Memory for Pictures. 3. There was a significant 3-way interaction: lows’ performance was worse hypnotized than during baseline; highs performance was about the same. 4. The Waterloo had a 6% increase but no group interaction. 5. Hypnosis ability didn’t lead to the effect. 6. The same goes for the Guiding Index – just practice effects were found. 7. There was an absence of the 3-way interaction found by Crawford. But the Gestalt task used by Crawford also was different. The shift may be due to primary process thinking (the stimulus is a jumping off point for decreased memory and organization) as opposed to holistic perception (in which there is increased synthesis while remaining responsible to stimulus). This may account for changes observed in highs. That is, highs may be responsible to rather than responsive to the stimulus.
Friedman, Howard; Taub, Harvey A.; Sturr, Joseph F.; Church, Katherine L.; Monty, Richard A. (1986). Hypnotizability and speed of visual information processing. International Journal of Clinical and Experimental Hypnosis, 34, 234-241
Following the determination of the luminance threshold of each S, high and low hypnotizable Ss were tested for speed of information processing using a backward masking paradigm with a bias-free and ceiling-free psychophysical task. No significant relationship between hypnotizability as measured by the Stanford Hypnotic Susceptibility Scale, Form A (SHSS:A) of Weitzenhoffer and Hilgard (1959) and speed of information processing was observed. The order of administering SHSS:A, pre- or postthreshold task, was significantly related to luminance threshold. Results were compared to other studies wherein some evidence for a relationship between hypnotizability and speed of visual information processing had been offered.
106 college students were tested using tachistoscopic presentation of stimuli. 52 Ss received the SHSS:A immediately prior to the experimental tasks, 54 immediately after, and testing was terminated for each Subject after they failed 3 successive items. The test flash was set at 0.3 log units above threshold, i.e. double the threshold intensity. A trial consisted of 2 observation intervals, separated by warning tones. The test flash occurred randomly in one of the two intervals. The S indicated which observation interval contained the test flash by pressing a button. Feedback tones gave S information about the correct response.
“The masking experiment was begun with the suprathreshold test flash occurring 250 milliseconds prior to the onset of the larger bright masking stimulus. As before, a two-interval forced -choice staircase procedure was used, but this time the test intensity was constant, and ISI was changed. If S ‘hit’ three trials in a row, ISI was decreased by 10 milliseconds. The ISIs continued to decrease in 10-millisec steps, until S “missed,” causing an increase in ISI” (p. 348).
RESULTS were analyzed by 2 x 2 x 2 ANOVA (Hypnotizability, sex, and order of hypnotizability measurement). High hypnotizables = 7-12 on the SHSS:A, and low hypnotizables = 0-6. Ss receiving SHSS:A prior to the tasks had a significantly lower luminance threshold (-1.99 log mL) than did those having it after tasks (-1.93 log mL), p<.05. None of the other analyses were significant. No significant relationships were observed vis a vis the masking task, and the mean masking thresholds were almost identical for the lows and highs. DISCUSSION. "Spanos (1982), in studying the effects of hypnotizability and suggestions in altering auditory sensitivity, reviewed the difficulties inherent in the measurement of perceptual accuracy and emphasized the role of response bias in the confounding of results" (p. 239). Secondly, these tasks reflect more fundamental, central processes and use more neutral stimuli than letter recognition used earlier. "Thus, while the masking effects of both the previous recognition tasks (masking by pattern) and the current detection tasks (masking by nearby contours) are presumably mediated through similar high level central processes, the differences in findings could possibly have been related to additional processing cues required in letter recognition" (p. 239). A footnote mentions, "Other studies have shown that with stimulus configurations similar to that used in the present study, there are significant central masking effects (Battersby & Wagman, 1962; Markoff & Sturr, 1971; Turvey, 1973)" (p. 239). "Quite intriguing is the luminance threshold finding which, although not as robust as one would desire, suggests that a hypnotic induction procedure given prior to a task may significantly affect sensitivity on that task. Speculatively, the relaxation suggestions inherent in SHSS:A may account for the changes in luminance threshold" (p. 239). Priebe, Frances A.; Wallace, Benjamin (1986). Hypnotizability, imaging ability, and the detection of embedded objects. International Journal of Clinical and Experimental Hypnosis, 34, 320-329. 40 Ss participated in an experiment designed to determine the influence of hypnotizability and imaging ability on cognitive performance. Individuals were asked to locate objects embedded within a series of pictorial scenes. For each scene, Ss were allocated a total of 6 minutes to find as many objects as possible. The objects were described to Ss prior to their search for them. Although there were no significant differences in total number of objects found as a function of hypnotizability, high hypnotizable Ss made significantly fewer errors in locating and identifying objects. This difference was attributed to the superior ability of the high hypnotizability Ss in visualizing the hidden objects and in using produced images as a means for correctly identifying them. This did not appear to be the case for the low hypnotizability Ss. It was this different in search strategy that may ultimately have led to the error difference between high and low hypnotizable Ss. High hypnotizables "have been shown to be better able to resist distractions in a tracking task (Mitchell, 1970); to concentrate on their own breathing or on a candle flame (Van Nuys, 1973); to listen to a target story along with a nontarget story and to report what they could remember about the target story (Karlin, 1979); and to perceive Necker cube and Schroeder staircase illusory reversals (Wallace, Knight, & Garrett, 1976). "Cognitive performance also has been shown to be influenced by imaging ability. For example, Paivio & Ernst (1971) found that when Ss were asked to identify letters, pictures, and geometric forms flashed to either the left or right visual field, those judged to be high imagers on a self-report test demonstrated better visual recognition. Similar findings were reported by Gur and Hilgard (1975) and Paivio (1978a, b). "In addition to reports that imaging ability and hypnotizability affect performance on a variety of cognitive tasks, there have also been reports that these two variables are related, at least to some degree (Diamond & Taft, 1975; Palmer & Field, 1968; Sutcliffe, Perry, & Sheehan, 1970). Some, however, have found that ... low imagers tend to be low in hypnotizability but high imagers may not necessarily be high in hypnotizability (Perry, 1973)" (pp. 320-321). A correlation between hypnotizability and imaging ability also was found by T'Hoen (1978) in a paired associates learning task in which imagery and concreteness of the word pairs was varied; and by other investigators using other research designs (Gur & Hilgard, 1975; Paivio, 1978a, b; Paivio & Ernst, 1971). Cognitive performance of high hypnotizable people was superior to low hypnotizables when the task was locating an imbedded letter ('Z') or completing double- digit arithmetic problems (Wallace and Patterson, 1984), possibly because highs may be using imagery to facilitate their performance. Highs performed better in detecting small differences in picture pairs when hypnotized but not when awake (Crawford and Allen, 1983). It appears that both highs and lows may use memorization of details for task performance, but only highs switch to a 'holistic' cognitive processing style, and mostly during hypnosis. Actually, Wallace and Patterson (1984) found that highs also used a holistic strategy in the waking state, not just in the hypnotized condition. In the present study, subjects were 40 volunteers (20 highly hypnotizable subjects with scores of 9-12 on the Harvard Group Scale of Hypnotic Susceptibility, and 20 lows with scores of 0-3). The task was to locate hidden objects in pictures, with level of difficulty rated as hard, medium, or easy. The outcome data were analyzed by analysis of variance for hypnotizability, picture difficulty, and time (six successive 1-min periods). In Session 1 subjects were administered the Harvard Scale and the Marks Vividness of Visual Imagery Questionnaire; in Session 2 the group Stanford Hypnotic Susceptibility Scale: C was administered. Before the actual experimental task of circling hidden pictures within larger pictorial scenes, each subject was given a list of words representing things that were embedded in the scenes, and asked to visualize each item. Then they were given six minutes to complete the item-finding task. They received three scores: the total number of objects located in six minutes, the number of objects correctly found, and number of errors. The 2x3x6 ANOVA was performed for each of these three dependent variables. high imagers may not necessarily be high in hypnotizability (Perry, 1973)" (pp. 320-321). A correlation between hypnotizability and imaging ability also was found by T'Hoen (1978) in a paired associates learning task in which imagery and concreteness of the word pairs was varied; and by other investigators using other research designs (Gur & Hilgard, 1975; Paivio, 1978a, b; Paivio & Ernst, 1971). Cognitive performance of high hypnotizable people was superior to low hypnotizables when the task was locating an imbedded letter ('Z') or completing double- digit arithmetic problems (Wallace and Patterson, 1984), possibly because highs may be using imagery to facilitate their performance. Highs performed better in detecting small differences in picture pairs when hypnotized but not when awake (Crawford and Allen, 1983). It appears that both highs and lows may use memorization of details for task performance, but only highs switch to a 'holistic' cognitive processing style, and mostly during hypnosis. Actually, Wallace and Patterson (1984) found that highs also used a holistic strategy in the waking state, not just in the hypnotized condition. In the present study, subjects were 40 volunteers (20 highly hypnotizable subjects with scores of 9-12 on the Harvard Group Scale of Hypnotic Susceptibility, and 20 lows with scores of 0-3). The task was to locate hidden objects in pictures, with level of difficulty rated as hard, medium, or easy. The outcome data were analyzed by analysis of variance for hypnotizability, picture difficulty, and time (six successive 1-min periods). In Session 1 subjects were administered the Harvard Scale and the Marks Vividness of Visual Imagery Questionnaire; in Session 2 the group Stanford Hypnotic Susceptibility Scale: C was administered. Before the actual experimental task of circling hidden pictures within larger pictorial scenes, each subject was given a list of words representing things that were embedded in the scenes, and asked to visualize each item. Then they were given six minutes to complete the item-finding task. They received three scores: the total number of objects located in six minutes, the number of objects correctly found, and number of errors. The 2x3x6 ANOVA was performed for each of these three dependent variables. Hypnotizability was not an important variable determining the number of correct objects located, but was significantly associated with the occurrence of fewer errors. Mean errors were 4.5 for Lows and 2.7 for Highs. Furthermore, hypnotizability was associated with using a 'holistic strategy' rather than a 'detail strategy' for finding items (self report on storing a memory of the list of objects-to-be found, preparatory to making the search, rather than checking back with the list during the search). Hypnotizability correlated with imaging ability r = .34, p < .05. In their Discussion, the authors noted that low hypnotizable people did not tend to use imagery for locating hidden objects, but would glance back and forth between the list and the picture--sometimes using a check-off mark next to items. High hypnotizables spent an average of 20 seconds looking at the list and becoming more familiar with it before starting to try to find the hidden objects. "One can assume this was a preparatory step in the formation of images for a subsequent visual search and the deployment of a holistic strategy during the search. "When asked why they engaged in their respective behaviors, low hypnotizables generally said that they were not too concerned with the list initially because they searched for hidden items by constructing objects out of discrepancies in the picture. Only when they found what they thought had the properties of an embedded object did the list become important. At that point they would refer back to the list to determine if the object was among those to be located. The list thus served as a tool for confirming the existence of an object they had found as well as a means for enabling them to double check which items they still had to find. High hypnotizable Ss generally claimed that they formed mental images in their heads for each item on the list. Once they found an object in the picture, they compared that object to the formed, mental image rather than referring back to the actual list. "As was previously mentioned, Crawford and Allen (1983) only found a difference in cognitive strategy between high and low hypnotizable Ss in the hypnotic state. In the present study, however, a strategy difference between these groups was noted in the waking state but only in terms of number of errors produced. A significant difference between high and low hypnotizables was not found in terms of the number of objects correctly found in a pictorial scene within a set period of time. It is possible that had cognitive strategies used in the hypnotic state been compared to those used in the waking state, our results might have been different. It is equally plausible, however, that hypnosis is not the critical factor in producing the difference between the results of the present study and those of Crawford and Allen (1983). It is possible that high hypnotizable Ss may show a holistic strategy when they are encouraged to involve themselves imaginatively and this encouragement is naturally provided in hypnosis, but it could also be present in the waking state if the task being used is appropriately structured. The task used in the present study is one that could be said to especially encourage the use of imagery, and in this sense, it may be relatively distinct from that used by Crawford and Allen. The fact that Ss practiced imagery on the element list beforehand simply reinforces the difference. Thus, the nature of the cognitive task may be what is at issue and not the presence or absence of as a means for enabling them to double check which items they still had to find. High hypnotizable Ss generally claimed that they formed mental images in their heads for each item on the list. Once they found an object in the picture, they compared that object to the formed, mental image rather than referring back to the actual list. "As was previously mentioned, Crawford and Allen (1983) only found a difference in cognitive strategy between high and low hypnotizable Ss in the hypnotic state. In the present study, however, a strategy difference between these groups was noted in the waking state but only in terms of number of errors produced. A significant difference between high and low hypnotizables was not found in terms of the number of objects correctly found in a pictorial scene within a set period of time. It is possible that had cognitive strategies used in the hypnotic state been compared to those used in the waking state, our results might have been different. It is equally plausible, however, that hypnosis is not the critical factor in producing the difference between the results of the present study and those of Crawford and Allen (1983). It is possible that high hypnotizable Ss may show a holistic strategy when they are encouraged to involve themselves imaginatively and this encouragement is naturally provided in hypnosis, but it could also be present in the waking state if the task being used is appropriately structured. The task used in the present study is one that could be said to especially encourage the use of imagery, and in this sense, it may be relatively distinct from that used by Crawford and Allen. The fact that Ss practiced imagery on the element list beforehand simply reinforces the difference. Thus, the nature of the cognitive task may be what is at issue and not the presence or absence of hypnosis" (p. 327). Wallace, Benjamin (1986). Latency and frequency reports to the Necker cube illusion: Effects of hypnotic susceptibility and mental arithmetic. Journal of General Psychology, 113 (2), 187-194. An experiment (N = 32) was conducted to assess latency of first apparent reversal (AR) and AR frequency while observing the Necker cube illusion. Subjects who were either high in hypnotic susceptibility (susceptibles) or low in hypnotic susceptibility (resistant subjects) observed the cube either while performing or not performing mental addition problems. Susceptibles reported perceiving the first AR more quickly and a greater frequency of ARs than did resistant subjects. Also, latency of the first AR was negatively correlated with AR frequency. These results were interpreted in terms of the ability of susceptibles to allocate concentrative or selective attention in a manner that was conducive to faster performance when faced with competing tasks. 1985 Acosta, Enrique; Crawford, Helen J. (1985). Iconic memory and hypnotizability: Processing speed, skill or strategy differences?. International Journal of Clinical and Experimental Hypnosis, 33, 236-245. The purported relationship between hypnotizability and speed of information transfer from iconic to short-term memory was studied in a comparison of 12 low and 12 high hypnotizable Ss. As in Ingram, Saccuzzo, McNeill, and McDonald (1979), high hypnotizable Ss showed less interference from a visual mask in the report of a briefly presented item than did low hypnotizable Ss when the mask delays were predictable. When the delay of the mask could not be anticipated, however, differences between high and low hypnotizable Ss disappeared. It is suggested that differences in information processing related to hypnotizability may be due to differences in strategy, skills, or other factors, rather than underlying information processing speed. that differences in information processing related to hypnotizability may be due to differences in strategy, skills, or other factors, rather than underlying information processing speed. Hypnosis may require concentrative or selective attention, which usually is measured by self-report (e.g. Absorption) or by experimental measures. Several investigations indicate that high hypnotizable people are better than low hypnotizables at focusing on a task and ignoring extraneous information (Brown, Crawford, Smith, Leu, & Brock, 1983; Graham & Evans, 1977; Karlin, 1979; Miller, 1975; Wallace, 1979; Wallace, Garrett, & Anstadt, 1974; Wallace, Knight, & Garrett, 1976). One way to study attentional processes is through the effect of presenting a mask (e.g. $$$$$) shortly after presenting a stimulus (e.g. ABCDE). Ingram (1979) found that highs had faster information processing, but that might be due to anticipation bias associated with the method of limits employed. This study uses both an ascending method of limits, like Ingram, and a condition in which the mask delays were presented randomly within another block of trials. RESULTS "While the present study replicated Ingram et al.'s (1979) findings when an ascending method of limits was used (the same used by Ingram et al.) differences were not found in processing when ISIs were presented randomly. Thus, these results suggest that high and low hypnotizable Ss do not differ in their information transmission rates, but rather they may differ in other aspects which mediate performance in this task" (pp. 241- 242). "Several lines of evidence point towards strategy or skill differences between high and low hypnotizable Ss as a possible explanation for the present findings. First, it was found that when Ss could anticipate the mask delay (the ascending condition), high hypnotizable Ss outperformed the low hypnotizables. When this anticipation was controlled, as in the random condition, the two groups did not differ when the data were scored by serial position. When the data were scored by a free recall scheme, there was a nonsignificant trend for high hypnotizable Ss to score higher than did the low hypnotizables. This trend suggests that high hypnotizable Ss may be more willing to guess, and to guess more accurately than low hypnotizables, when they have partial information about a letter, and/or they may have greater skill in perceiving incomplete information. The latter suggestion finds indirect support from Crawford (1981) who reported that high hypnotizable Ss can process fragmented stimuli (Gestalt Closure tests, see Thurstone & Jeffrey, 1966), significantly better than can low hypnotizables. High imagers have been shown also to perform significantly better than low imagers in Gestalt Closure tasks (Ernest, 1980). At a speculative level, given that recent research has suggested that iconic memory may be a right hemisphere phenomenon (e.g. Cohen, 1976, but also see DiLollo, 1981), and high hypnotizable Ss outperform low hypnotizables on certain right hemisphere tasks (e.g. Crawford, 1981), it may be asked if the trends found with the free recall scoring scheme in the present study might be a reflection of differential right hemisphere processing. Such a hypothesis could be investigated in future research by comparing the performance of high and low hypnotizable Ss, as possibly moderated by visuo-spatial ability, for stimuli presented to the left versus the right visual hemifield (Ernest, 1983). "A second set of evidence in favor of strategy differences was found in Saccuzzo et al. (1982) which was published after the data for the present experiment were collected. In the Saccuzzo et al. (1982) paper, which was an extension and replication of Ingram et al. (1979), the same mask delay was used throughout a 10-trial block. The order of the blocks (i.e., the mask delays) was random. Thus, while S did not know which mask delay was used in the first trial of a block, the remaining 9 trials were the same and could be anticipated. During the first session, high hypnotizable Ss outperformed the low hypnotizables, but these differences disappeared on the second testing session. These results suggest that practice may have affected performance, rather than any underlying information processing speed differences" (pp. 242-243). Oliver, J. M.; Burkham, Robert (1985). 'Comments on three recent subliminal psychodynamic activation investigations': Reply to Silverman. Journal of Abnormal Psychology, 94 (4), 644. Contends that the present authors' (see PA, vol 69:1571) failure to replicate L. H. Silverman's (1976) description of subliminal psychodynamic activation, which was disputed by Silverman (see PA, vol 73:12007), can be traced in part to Silverman's (1978) description of the "symbiotic" stimulus (MOMMY AND I ARE ONE"), 1 of the 2 experimental stimuli used, as a "ubiquitous therapeutic agent". It is suggested that, although Silverman's willingness to modify his theory in light of empirical findings is commendable, modifications that are too frequent and numerous will pose problems for both theory and research. (5 ref) Porterfield, Albert L.; Golding, Stephen L. (1985). Failure to find an effect of subliminal psychodynamic activation upon cognitive measures of pathology in schizophrenia. Journal of Abnormal Psychology, 94 (4), 630-639. Replicated the work of L. H. Silverman and colleagues (see PA, vols. 43:14557 and 46:1566) using 30 21-59 year old schizophrenics. Ss were exposed to an aggressive, a merging, and a meaningless lexical stimulus in a within-S design. Dependent variables were inkblot through pathology and form quality, as measured on Rorschach and Holtzman Inkblot Techniques, and performance on the interference task of the Stroop Color-Word Test. Analyses of variance conducted on simple poststimulation scores, rather than on unreliable change scores, revealed no effect of stimulus content. Predicted interactions between stimulus content, Ss self-object differentiation, and temporal position of the assessment tasks did not emerge. Findings do not support Silverman's hypothesis that subliminal tachistoscopic presentations of stimuli with aggressive content temporarily increase thinking disorder in schizophrenics. (44 ref.) Porterfield, Albert L. (1985). 'Comments on three recent subliminal psychodynamic activation investigations': Reply to Silverman. Journal of Abnormal Psychology, 94 (4), 645-646. Contends that in defending his nonverbal pathology measure against the claim that it lacks demonstrated validity, L. H. Silverman (see PA, vol 73:12007) painted a misleading picture of its face validity. A correction to that picture is presented, and the impact of the present author and S. L. Golding's (see PA, vol 73:11992) findings on subliminal psychodynamic activation explanations of schizophrenic thought disorder is defended, despite the absence of a nonverbal pathology measure. (5 ref) Silverman, Lloyd H. (1985). 'Comments on three recent subliminal psychodynamic activation investigations': Rejoinder to Oliver and Burkham and to Porterfield. Journal of Abnormal Psychology, 94 (4), 647-8. Considers the replies of A. L. Porterfield (see PA, vol 73:11991) and J. M. Oliver and R. Burkham (see PA, vol 73:11985) to the critique of the present author (see PA, vol 73:12007). The original criticisms are seen as valid. A critical deficiency in the design of Porterfield and S. L. Golding's (see PA, vol 73:11992) study is viewed as disqualifying it as a fair attempt at replication. It is suggested that although Oliver and Burkham's (see PA, vol 69:1571) study was well-designed, statements made in their write- up are unwarranted. (12 ref) Silverman, Lloyd H. (1985). Comments on three recent subliminal psychodynamic activation investigations. Journal of Abnormal Psychology, 94 (4), 640-643. Contends that unwarranted statements about subliminal psychodynamic activation research by the present author (1976, 1983, 1984) were made in the work of J. M. Oliver and R. Burkham (see PA, vol. 69:1571); K. C. Haspel and R. S. Harris (see PA, vol 69:4952) and A. L. Porterfield and S. L. Golding )see PA, vol 73:11992). Issues considered include the choice of subliminal stimuli, the present author's statistical analyses, and the necessity of a nonverbal measure of psychopathology in this research (17 ref).