Authors studied 10 people known trance channels–all had been channeling for more than one year. Used an anthropological field method. Electrode was placed only on left occipital (O1) area, referenced to left ear. Calculated difference between each S’s pre- trance and trance EEG beta percentages, for alpha and theta percentages also.
Basically, the pre-trance versus trance sums of differences scores were greater than the post-trance versus trance sums of different scores for each of the three frequency bands–indicating a residual of the trance state. There were large, statistically significant increases in amount and percentage of beta, alpha and theta brainwave activity, and some suggestion of a pattern. The large amount of beta differentiates these Ss from what has been observed with meditators (increases in alpha and theta). Among the Subjects, large amounts of beta activity were recorded continuously throughout the trance period and were coupled with large amounts of high amplitude alpha and theta (relative to the pre- and post-trance states).
The authors compare these results to older hypnosis literature. They conclude that the trance channeling state may be a distinctive state characterized by a particular EEG profile that differs from that found in certain meditative states, hypnotic states, various pathological states, or the waking states of the trance channel Subjects who participated in the study. Authors also liken the differences seen between trance and non-trance states of these Subjects to the differences seen for different alter personalities among people diagnosed with Multiple Personality Disorder.

The foregoing research suggests that the trance channeling state, as measured in the current study, is characterized by large, statistically significant increases in amount and percentage of beta, alpha and theta brainwave activity. There appear to be definite neurophysiological correlates to the trance channeling state, and furthermore there is some evidence that these correlates may be patterned. This pattern might be provisionally compared to those associated with other altered states of consciousness.

abourin, M. E.; Cutcomb, S. D.; Crawford, H. J.; Pribram, K. (1990). EEG correlates of hypnotic susceptibility and hypnotic trance: Spectral analysis and coherence. International Journal of Psychophysiology, 10, 125-142.

EEG was recorded during waking rest, hypnosis (rest, arm immobilization, mosquito hallucination, hypnotic dream), and waking rest. Twelve very low and 12 very highly hypnotizability subjects participated. Evaluations were fast-Fourier spectral analysis, EEG coherence between selected deviations, and maximum spectral power within EEG bands. In eyes-open and eyes-closed conditions in waking and hypnosis, highly hypnotizability subjects generated substantially more mean theta power than did low-hypnotizable subjects at all occipital, central, and frontal locations in almost all conditions of waking and hypnosis, with a larger difference in frontal locations. Both low and high hypnotizables showed increased mean theta power in hypnosis, suggesting an intensification of attentional processes and imagery enhancement. Mean alpha power was never a predictor of hypnotic susceptibility. Interactions with hypnotic susceptibility showed that highly susceptible subjects had more beta activity in the left than in the right hemisphere, whereas low-susceptible subjects showed only weak asymmetry. No main effects for or interactions between waking/hypnosis and hypnotic level were found for coherence between derivations or maximum spectral power within theta, alpha, and beta EEG bands

Bick, C. H. (1989). An EEG-mapping study of ‘laughing’: Coherence and brain dominances. International Journal of Neuroscience, 47, 31-40.
Laughter is triggered by pleasurable psychoemotional stimuli and may have healing potential. According to split-brain studies, psychoemotional stimuli are bound up with emotional activity in the right side of the brain. This suggested the idea of studying laughter generated by different sources with regard to electrical brain activity in the right and left hemispheres. This study first used subjects in normal consciousness and with laughter under hypnosis to study the neurophysiological processes connected with laughter.

De Pascalis, Vilfredo; Marucci, Francesco S.; Penna, Pietronilla M. (1989). 40-Hz EEG asymmetry during recall of emotional events in waking and hypnosis: Differences between low and high hypnotizables. International Journal of Psychophysiology, 7, 85-96.

Sixteen high and thirteen low hypnotizability women, who had participated in our previous study (De Pascalis et al., 1987), were enrolled in a hypnotic session. After the hypnotic induction they were requested to recollect 2 positive and 2 negative personal life experiences. IN our previous study subjects performed similar tasks in a waking-state. Hypnotizability was evaluated the first time with the HGSHS and, a second time, individually, with the Stanford C. The State Trait Anxiety Inventory, Maudsley Personality Inventory, and Tellegen Absorption Scale were administered. Upper-trapezius electromyogram (EMG) and bilateral electroencephalogram (EEG) activities within the 35-45 Hz band were recorded. Self-report rating scores for vividness of visual imagery and emotional feeling of the material recalled were evaluated. The 40-Hz EEG amplitude and the left and right hemisphere 40-Hz EEG densities were obtained.
The data collected in hypnosis were compared with those in the waking-state. High hypnotizables, while they were in hypnosis, showed an increase of 40-Hz EEG density during emotional recall compared with rest periods. In contrast, low hypnotizables, after hypnotic induction, showed no density during emotional recall compared with rest periods. In contrast, low hypnotizables, after hypnotic induction, showed no density change during tasks compared to the rest conditions. Different hemispheric trends were found between groups. Highs showed an increase of 40-Hz EEG density over both hemispheres during positive emotions and a density increase in the right and a density reduction in the left during negative ones. This hemispheric trend was found in waking and hypnotic conditions although in the hypnotic condition more pronounced hemispheric patterns were observed. The Tellegen Absorption Scale was found positively related to hypnotizability and with the level of 40-Hz density increase on the right hemisphere during emotional tasks. High hypnotizables, with respect to the lows, were able to access affects more readily. They also showed a greater hemispheric specificity in waking and hypnotic conditions.

Spiegel, David; Bierre, Pierre; Rootenberg, John (1989). Hypnotic alteration of somatosensory perception. American Journal of Psychiatry, 146, 749-754.

The effects of hypnotic alterations of perception on amplitude of somatosensory event-related potentials were studied in 10 highly hypnotizable (HH) Subjects and 10 Subjects with low hypnotizability. The HH Subjects showed significant decreases in amplitude of the P100 and P300 waveform components during a hypnotic hallucination that blocked perception of the stimulus. When hypnosis was used to intensify attention to the stimulus, there was an increase in P100 amplitude. Findings are consistent with observations that HH individuals can reduce or eliminate pain by using purely cognitive methods such as hypnosis. Together with data from the visual system, these results suggest a neurophysiological basis for hypnotic sensory alteration.

Four conditions were presented in random order to each Subject. Normal Attention – subjects were instructed to button-press each time they felt the target stimulus. Passive Attention – subjects were instructed to attend to the stimuli but not button-press. Hypnotic Attention – subjects received a hypnotic induction (eye closure and arm levitation, which provided behavioral confirmation; then instructed to attend carefully to the stimuli, which they were told to experience as ‘pleasant and interesting,’ and button-press in response to targets. Hypnotic Obstructive Hallucination – hypnotic induction exercise was followed by the hypnotic suggestion of a local anesthetic, such as novocaine, spreading from fingers to hand to forearm on the stimulated limb; then instructed to make the limb cold, tingling, and numb; then told to button-press if they felt any of the target stimuli.
Experimenter was blind to hypnotizability scores.
Results were that the Highs showed significant decreases in P100 (45%) and P300 (38%) amplitudes during a hypnotic hallucination which blocked perception of the stimulus, but an increase (35%) in P100 amplitude when hypnosis was used to intensify attention to the stimulus. The authors view this as cognitive flexibility akin to the clinical situation in which high hypnotizables reduce or completely eliminate pain. They consider this evidence (along with earlier findings on similar blocking of perception in the visual system) of a neurophysiological basis for hypnotic sensory alteration.

Aravindakshan, K. K.; Jenner, F. A.; Souster, L. P. (1988). A study of the effects of hypnotic regression on the auditory evoked response. International Journal of Clinical and Experimental Hypnosis, 36, 89-95.

Hypnotic regression in 6 hypnotizable Ss experienced in regression was studied by means of the auditory evoked response (AER). AER latency and amplitude is affected by arousal, attention, stimulus strength, and age. Ss aged between 27 and 61 years were regressed to the age of 7-9 years, and AERs were compared among three states of consciousness: normal awareness, hypnotic relaxation, and hypnotic regression. There was no change in AER morphology in the direction of that seen in children. Thus, age regression is not seen as a reversion to an earlier stage of neurological development but perhaps as role playing which is spontaneous and uninhibited, with the benefit of innocent belief in its accuracy.

Raikov (1982) regressed 2 experienced Ss, comparing his results with those of actors acting as children and low hypnotizable subjects; he claimed to be able to reproduce neonatal reflexes in the highly hypnotizable Ss but not in the actors and low hypnotizable subjects.
AER’s were used “because latency of the major waves and amplitude of the response is affected by level of arousal and attention…, strength of the stimulus, and, more importantly for this study, by age…. Surwillo (1981) noted that peak latencies of AERs were 16-21 msec longer in children aged 9-13 than in adults…” (p. 90)

Changes in the intensity of light stimulation can cause significant shifts in the amplitude and latency of the visual evoked response, but neither the amplitude nor the latency have been changed by suggested alterations in stimulus intensity during hypnosis (Andreassi, Balinsky, Gallichio, de Simone, & Mellers, 1976; Beck & Barolin, 1965; Beck, Dustman, & Beier, 1966; Zakrzewski & Szelenberger, 1981). Similarly, significant changes were seldom found in the AER with suggested variations of sound intensity during hypnosis (Amadeo & Yanovski, 1975) and in somatosensory responses to electrical stimuli applied to the fingers with suggested anesthesia during hypnosis (Halliday & Mason, 1964). Deehan and Robertson (1980) were able to abolish the AER completely during hypnosis, but their stimuli were very different from that used in the present study.
“In all such studies, hypnosis and suggestions were aimed at changing the intensity of the stimulus to S’s awareness, while the actual intensity of the stimulus was unaltered. In the present study, the authors attempted to find whether the morphology of the AER in children could be reproduced by age regression, without altering the nature or intensity of the stimulus in its delivery…. Like previous investigators, the present authors noticed that the tracings were cleaner and easier to produce during hypnosis (see Figure 1), although the changes in neurological development observed by Raikov (1982) were not evident” (pp. 93-94).

De Pascalis, Vilfredo; Silveri, Alessandra; Palumbo, Giovanni (1988). EEG asymmetry during covert mental activity and its relationship with hypnotizability. International Journal of Clinical and Experimental Hypnosis, 36, 38-52.

Parietal-occipital EEG was recorded bilaterally while 20 high and 20 low hypnotizable Ss performed, in the eyes-closed condition, 2 covert right-hemisphere tasks (visual long-term memory and fantasy) and 2 covert left-hemisphere tasks (multiplication and verbal long-term memory). Ss were not, however, hypnotized during any aspect of the psychophysiological testing. After each task, Ss rated orally their degree of involvement in the tasks. The integrated amplitude alpha, the alpha density, and the alpha ratio as a measure of hemispheric asymmetry, were evaluated. Finally, the proportion of relatively greater right activation periods during right-hemisphere tasks minus the analogous proportion during left-hemisphere tasks was used as index of hemispheric specificity. The high hypnotizable Ss showed significantly higher alpha amplitude than the low hypnotizables; the alpha amplitude was correlated with hypnotizability, while the alpha density was not. The alpha amplitude of the right hemisphere during right- hemisphere tasks was significantly lower than the same amplitude during left-hemisphere tasks, while no significant differences related to task-type were detected in the left hemisphere. The pattern of task-effect on alpha ratio scores was the same as that on alpha amplitudes. Verbal and multiplication ratings were related to the alpha ratio, imaginative- visual memory ratings were not. No differences in hemispheric specificity between high and low hypnotizable Ss were found to exist, and no relationship between hypnotizability and hemispheric specificity was observed.

The authors review the literature on differences between the two hemispheres’ involvement during hemisphere-specialized tasks. The ratio between left- and right- hemisphere alpha amplitudes has been shown to be a reliable measure of hemisphere lateralization as a function of task demands (Amochaev & Salamy, 1979).
They also review the literature on EEG asymmetry and hypnotizability. Most investigations used tasks with a problem solving component, whereas this study used “a covert numeric task and other covert self-generated tasks in which the range of cognitive activities resembled natural thinking” (p. 40).
Purposes of this research were “to investigate whether (a) the amount of alpha in EEG is correlated with hypnotizability, (b) high hypnotizable Ss would reveal higher hemispheric specificities during covert mental tasks than low hypnotizable Ss, and (c) verbal-numeric tasks involve more left-hemisphere activation and imaginative-visual tasks more right-hemisphere activation” (p. 40).
The subjects were 40 women (from an original pool of 71), aged 19-23, with no previous experience using hypnosis. To minimize the possible effects of expectation, hypnosis was not mentioned in the invitation to participate in research. All subjects were tested first with the Harvard Group Scale of Hypnotic Susceptibility, then with the Stanford Scale of Hypnotic Susceptibility (SHSS:C). The SHSS:C was used to select 20 high hypnotizables (defined as having a score 1 standard deviation above the group mean of 6.51) and 20 low hypnotizables (with scores 1 standard deviation below the group mean). The mean score for highs was 10.05 (S.D. = .88) and mean score for lows was 2.75 (S.D. = 1.49).
Although subjects were selected on the basis of their measured hypnotizability, hypnosis was not used during the investigation’s psychophysiological testing. However, they were required to relax and keep eyes closed during trials on the tasks. After each trial, the subjects rated their involvement in the task.
Tasks used for this research were: 1. Visual long-term memory. Ss were asked to recall from memory pictures, places, faces, or visual scenes that were in a movie, but not scenes with a negative content. 2. Fantasy. Ss were requested to fantasize about something new that they like (nothing from past experience, and nothing sexual). 3. Multiplication. Ss were asked to multiply 2 serially, as, 2 x 2 = 4, x 2 – 8, etc., and to do it verbally without visual representation. 4. Verbal long-term memory. Ss were requested to think of some poem, speech, or other verbal material that they could recall from memory, and to repeat it mentally, to themselves.
Results can be summarized as follows.
Hypnotizability correlated .38 and .35 with right alpha amplitude and left alpha amplitude during baseline (statistically significant).
There was a significant association between alpha density and hypnotizability, when the group was divided at the median on density. (Alpha density = the time periods in which the alpha was present over the 6-second epochs accumulated during each 1-minute period which preceded the tasks). This association may be seen in the Table that follows:
SHSS:C Alpha Density Low High
+ 6 13
– 14 7
Chi Square = 3.61, p <.05 There was a significant interaction between type of task (verbal-numeric, imaginative-visual memory) and hemisphere, which was attributable to changes in alpha amplitudes in right hemisphere, according to tasks. "Alpha amplitude of the right hemisphere during right-hemisphere tasks was significantly lower than during left- hemisphere tasks, while no significant differences were detected in the left hemisphere as a result of the differences between left- and right-hemisphere tasks" (p. 44) Alpha ratio = (Right-hemisphere alpha - Left-hemisphere alpha) / (Right- hemisphere alpha + Left-hemisphere alpha) exhibited the same pattern as for alpha amplitudes. The ANOVA 2 (high/low) x 2 (right tasks/left tasks) repeated measures on alpha ratio revealed a significant main effect for tasks, and a significant interaction between right-left tasks and hypnotizability. "During right-hemisphere tasks there were no significant differences (p <.5) [sic] in alpha ratio between high and low hypnotizable groups, while during the multiplication task, the low hypnotizable Ss evidenced a higher mean alpha ratio (p <.05) than the high hypnotizable group (.08 & .04, respectively); identical ratios were found during verbal tasks" (p. 45). Task involvement was expected to be positively related with left-hemisphere tasks, but negatively related to right-hemisphere tasks (i.e. greater subjective involvement in the task would be associated with more negative alpha ratios, showing a bias towards right- hemisphere activation. "Verbal ratings were substantially related to alpha ratios (rho = 0.82; p <.01), and multiplication ratings moderately related to alpha ratios (rho = 0.31; p <.05); visual memory and fantasy ratings were not related to alpha ratios (r = -.04 & r = - .18, respectively)" (p. 45). Hemispheric specificity was defined as the proportion of greater relative right- hemisphere activation periods during right-hemisphere tasks minus the analogous proportion during left-hemisphere tasks. The authors did an analysis to "verify whether the task rating moderates the hemispheric specificity (i.e., the level of subjective involvement in a task is related to the level of hemispheric lateralization, while S is carrying it out)" (p. 46). They concluded that hypnotizability (SHSS:C) is not significantly related to Ss' hemispheric specificity. In the discussion, the authors present a Table summarizing the results of similar investigations. They mention that the alpha-hypnotizability relationship may depend on which alpha variable is taken into account, or whether eyes-open/closed is varied. They conclude that the different methodological procedures render any comparison of results across studies very difficult. They note that there was a significant correlation between alpha amplitude and hypnotizability even though Ss did not know in advance that hypnosis would be part of the experiment (the hypothesis proposed by Dumas, 1977, to account for this type of correlation). "One possible explanation of these data might lie in a different level of arousal in the high and low hypnotizable Ss: the high hypnotizable Ss might have been simply more relaxed than the lows. "Nevertheless, his explanation must be taken with caution. The study of Paskewitz and M. T. Orne (1973), in fact, pointed out that in dark-adapted Ss, the relaxation condition does not produce increases of alpha activity. In a further study, contrary to previous reports, M. T. Orne and Paskewitz (1974) also found that a reduction in alpha activity is not a necessary consequence of apprehension or heightened arousal. Thus, it is not yet clear whether a decrease in anxiety tends to cause an increase in alpha density and vice versa" (p. 48). Lorig, Tyler S.; Schwartz, Gary E. (1988-89). EEG activity during relaxation and focal imagery. Imagination, Cognition and Personality, 8, 201-208. EEG activity was recorded in nine volunteer subjects while they engaged in eight cognitive tasks. The tasks involved mental arithmetic, relaxation imagery, food imagery and imagery related to "neutral" stimuli (bicycle and automobile). Period analysis of the EEG indicated significant differences in EEG factor activity related to tension and anxiety for the subtraction, relaxation and food imagery trials. Imagery of heaviness and the subject's favorite dessert produced EEG factor activity most characteristic of relaxation. Results of this study are discussed in terms of the relation of odor to food imagery and the ecological validity of the use of food imagery in relaxation training. NOTES Lorig, in a comparison of spectral and period analysis techniques, found that period analysis had greater sensitivity to task-related EEG effects. More recently, Lorig and Schwartz applied factor analysis to EEG period data and found that the factors identified tended to show greater homogeneity and correspondence to self-report than the traditional EEG bands of alpha, theta and beta. Period analysis reduces data to a histogram of the number of waves of various frequencies which occur during each 10 second data collection epoch for each task. As is evident from Finding 1, the 8 tasks tend to stratify into two groups which either increase or decrease in Factor 1/theta activity over time. Those tasks which decrease over time seem to be performance or practice-related and include Serial subtraction of threes, of sevens, relaxation imagery of heaviness (HVY) and instructions to concentrate on the word "one" as they inhaled and exhaled (BCON). These tasks may change little in their cognitive demands on the subjects over time. The other tasks (imagery of their first bicycle, imagery of their earliest ride in a car, imagery of their favorite main course, imagery of their favorite dessert) may be more evocative to the Ss since they were asked to recall events from their personal experience. The recall of some of these experiences may kindle the subsequent recall of other events and account for the increases in theta and Factor 1. It is also possible that theta and Factor 1 are attention- related. Thus, as the S participates in a task which changes little over time, attention is diminished. If, however, the task continues to evoke other personally relevant events, attention will be maintained and may even increase over time. If this later hypothesis is correct, the Favorite Dessert task may be of use clinically since it produces EEG patterns associated with less tension and anxiety and also less boredom. This task also produced self-reports of greater happiness (p = .0001) and was not different from relaxation imagery of heaviness and instructions to concentrate on the word 'one' as they inhaled and exhaled in self reports of relaxation, tension or calm. The results of this study indicate that imagery of food, especially one's favorite dessert, has relaxation effects apparent in EEG and self-report. These effects may indicate that food-related odorants exert their relaxation effects by producing imagery of food. Such effects should not be surprising given the early history of systematic desensitization training in which food was often used as a competing stimulus for anxiety-provoking stimuli. Spiegel, David; Barabasz, Arreed F. (1988). Effects of hypnotic instructions on P300 event-related-potential amplitudes: Research and clinical applications. American Journal of Clinical Hypnosis, 31, 22-27. Apparently conflicting findings in two recent studies of the effects of hypnotic hallucination on the P300 component of cortical event-related potentials are examined. In one study, Barabasz and Lonsdale (1983) found an increase in P300 amplitude in response to hypnotic anosmia instructions. However, Spiegel, Cutcomb, Ren, and Pribram (1985) obtained a decrease in P300 amplitude after instructing high hypnotizables that an imaginary cardboard box blocked their view of the stimulus generator. These differences are reconciled on the basis of differences in the hypnotic instructions given. The former study employed language which emphasized negation ("You will not smell anything at all"), while the latter had subjects focus on a competing obstructive hallucination. The anosmia subjects were surprised when they smelled anything at all, leading to an enhanced P300 response, while the subjects in the visual study were so absorbed in the hallucinated obstruction that perception of the stimulus was reduced. Clinical implications of these two studies are examined. 1987 De Pascalis, Vilfredo; Marucci, Francesco; Penna, Pietronilla M.; Pessa, Eliano (1987). Hemispheric activity of 40 Hz EEG during recall of emotional events: Differences between low and high hypnotizables. International Journal of Psychophysiology, 5, 167-180. This study evaluates individual differences in hypnotizability as reflected in waking-state hemispheric engagement during recollection of 3 positively and 3 negatively valenced personal life events. The State-Trait Anxiety Inventory, Maudsley Personality Inventory, Tellegen Absorption Scale and Harvard Group Scale of Hypnotic Susceptibility (Form A) were administered. Electromyogram (EMG) and bilateral electroencephalogram (EEG) activities within the 40-Hz band were recorded during rest and task conditions in 22 high and 21 low hypnotizable women. Self-report rating scores for vividness of visual imagery and emotional feeling of the material recalled were evaluated. The 40-Hz EMG amplitude and both hemisphere 40-Hz EEG densities were obtained. A 40-Hz EEG ratio, as a measure of hemispheric asymmetry, and a hemispheric specificity index were also computed. High hypnotizables showed significantly lower 40-Hz EEG density than low hypnotizables in all experimental conditions. The relationship between lateralization of 40-Hz EEG and emotional processing was moderated by hypnotizability. High hypnotizables, with respect to rest condition, showed an increase of density over both left and right hemispheres during two of the three positive emotional tasks, while they showed a depressed activity over the left and an increased activity over the right during negative emotional tasks. Low hypnotizables, on the other hand, did not exhibit differential hemispheric patterns that could be attributed to different emotional valences. The high group showed greater hemispheric specificity in the predicted direction than the low group. High subjects exhibited greater ratings of absorptive ability and emotional feeling than low subjects. Anxiety and EMG levels did not differ between groups. EMG was dependent on the type of emotion which showed greater activity in the negative emotion condition compared with the positive one. Makarec, K.; Persinger, M. A. (1987). Electroencephalographic correlates of temporal lobe signs and imaginings. Perceptual and Motor Skills, 64, 1124-1126. Significant correlations (0.50) were observed between scores for the Wilson-Barber Inventory of Childhood Memories and Imaginings and the experiences that are indicative of temporal lobe lability. In addition, positive correlations (0.42) occurred between temporal lobe EEG measures (scalp electrodes) and numbers of temporal lobe signs. The numbers of alpha seconds per minute from the occipital lobes were correlated (0.57) with the Wilson-Barber cluster that indicated interests in 'altered states'. Scores on the childhood imaginings section of the Wilson-Barber Inventory were correlated (0.44) with the numbers of spikes per minute over the temporal lobes when the eyes were closed. NOTES Persinger and DeSano (1986) found that people who display temporal lobe signs were also more likely to have more imaginings (as defined by Wilson and Barber's (1983) Inventory of Childhood Memories and Imaginings) and to be more suggestible as indicated by Spiegel's Hypnosis Induction Profile" (p. 1124). Subjects in this investigation were 12 male and 18 female students, ages 18-39 (M = 25 years) Bipolar measures were taken from just above the ears (approximately T3-T4) and the occipital lobe (01-02). Number of alpha seconds per minute and number of spikes per minute from each lobe was taken for 10 minutes (5 successive pairs of 1 minute eyes- open, 1 minute eyes-closed). "The total Wilson-Barber score was significantly (p <.01) correlated ... with the major (0.46) and minor (0.50) temporal lobe clusters but not with two clusters of control items: normal psychological experiences (0.21) and mundane proprioceptive experiences (0.29). These correlations are similar to those in the Persinger and DeSano study (0.60, 0.50, 0.13, and 0.14, respectively). Like the first study (0.53), the items that were most associated with dissociation (depersonalization) were best correlated with the Wilson- Barber scores (0.60). The Wilson-Barber subcluster: adults' extreme experiences (Items 44 through 52, that indicate physiological changes associated with thinking) was again most strongly correlated with the major (0.55) and minor (0.65) temporal lobe clusters; these values were 0.42 and 0.52 in the first study" (p. 1125). "The only statistically significant (p < .01) correlations between the Wilson-Barber scales and the EEG measures were between the number of alpha seconds from the occipital lobe (with the eyes closed) and the [Wilson-Barber] 'altered state' cluster (r = 0.57; Items 33, 41, 42, 43). A weaker correlation (0.36) occurred between the number of alpha seconds per min. (eyes closed condition) and childhood vestibular experiences (items 1, 2, 3, 10, 24)" (p. 1126). 1886 De Pascalis, Vilfredo; Palumbo, Giovanni (1986). EEG alpha asymmetry: Task difficulty and hypnotizability. Perceptual and Motor Skills, 62, 139-150. Parieto-occipital EEG alpha was recorded bilaterally, while 20 high- and 20 low-hypnotizable women performed one left-hemisphere and one right-hemisphere task of low difficulty and two other comparable tasks of high difficulty. Every task was performed twice, once with eyes open and once with eyes closed. All subjects were right-handed. The tasks were originally selected to be of high and low difficulty. The subjective rating of task-difficulty was also evaluated. The integrated amplitude alpha and the alpha ratio (R- L/R + L) were the dependent variables. The highly hypnotizable women showed significantly higher alpha amplitude in eyes-closed condition than the low scorers; this difference disappeared during task performance and in the eyes-open condition. The left- tasks showed lower alpha amplitude in both hemispheres than right-tasks and baseline. The right-hemisphere alpha amplitude was lower than left in all experimental conditions. On tasks of high and low difficulty there was different hemispheric behavior on right and left tasks. Performance reflecting the right and left hemispheres in the low-difficulty condition showed no changes between baseline, right- and left-tasks, while under high difficulty there was a decrease in alpha amplitude in the right and even more marked decrease in the left hemisphere during left-tasks. The pattern of task effects for ratio scores was the same as for alpha amplitude, however, despite the analysis of alpha scores, an interaction of hypnotizability x task-difficulty was detected. The highly hypnotizable women showed less negative alpha ratio during a task of low difficulty than during tasks of high difficulty; the reverse was true for the low-hypnotizable women. Finally, the highly hypnotizable subjects showed less subjective difficulty during performance than the low scorers. DeBenedittis, Giuseppe; Sironi, Vittorio A. (1986). Depth cerebral electrical activity in man during hypnosis: A brief communication. International Journal of Clinical and Experimental Hypnosis, 34, 63-70. To the authors' knowledge, hypnosis has never been induced in epileptic patients during a depth EEG study. This neurosurgical diagnostic procedure has been routinely used in medically resistant epileptic patients for the preoperative exact delimitation of the epileptogenic lesion. It offers a unique opportunity to obtain fundamental information on the possible neurophysiological mechanisms implicated in hypnosis. Observations were carried out on 1 patient affected by medically resistant partial seizures with complex symptomatology. A chronic deep electrode study explored rhinencephalic structures as well as specific target areas of the cerebral cortex. Background electrical activity during hypnosis showed a significant decrease of slow waves and an increase of alpha and beta rhythms, with constant increase of amplitude, when compared to activity in the pre- and posthypnosis states. Focal interictal abnormalities were dramatically reduced during hypnosis. NOTES Hypnotizability was assessed with the Barber Suggestibility Scale in order to test for suggestibility without a prior induction of hypnosis. The patient's score was 7 out of 8 possible. Patient was hypnotized with a standard induction procedure (Barber & Calverley, 1963). Experimental Protocol: 15 minutes resting baseline; 15 minute test of mental imagery (waking suggestions with imagination instructions); hypnosis with progressive relaxation; suggestions for dissociation; suggestions for amnesia; arousal from hypnosis (the patient was successful with positive hallucinations, catalepsy, total amnesia, and spontaneous analgesia); and posthypnosis awake and alert (5 minutes eyes open, 5 minutes eyes closed, then 15-minute recording of post-treatment waking baseline). EEG background activity was scored for the number of sec/minute of delta (0-4), theta (4-7), alpha (8-12), and beta (13-30) rhythms, for each 5-min period. Score = percent as related to the 1-minute epoch. Number, amplitude, and diffusion of interictal spikes also were measured but ictal activity was not recorded during the periods considered. Experimenters also measured heart rate, respiratory rate, and mean blood pressure. ANOVA for 4 conditions (resting, waking suggestion, hypnosis, and posthypnosis) was computed for background and for focal interictal activities, and the t-test used to evaluate significant differences. ANOVA indicated a significant effect across the four experimental conditions for theta and alpha in the temporal anterior cortex, temporal posterior cortex, and frontal convexity cortex. The effect was attributable only to changes in theta and alpha between baseline and hypnosis (theta decreasing, alpha increasing as the patient went into hypnosis). No other significant difference was found. Following arousal from hypnosis, EEG activity was similar to the EEG activity before the induction. Interictal focal abnormalities were reduced during hypnosis, compared with before hypnosis. The effect was due to changes in the area of Ammon's horn, the amygdala, the posterior temporal cortex, the mesial temporal cortex, and the inferior temporal cortex. In their Discussion, the authors note that their data supports earlier work indicating that the limbic system is implicated in hypnosis. The cite the publications of Arnold (1959, International Journal of Clinical and Experimental Hypnosis) and Crasilneck, McCranie, and Jenkins (1956). The latter authors observed EEG records taken during brain surgery on one patient. Hypnosis terminated every time the hippocampus was stimulated, leading them to suggest that the hippocampus is part of the neural circuit involved in hypnosis. "If it is assumed that a convulsion can be considered a result of both pathophysiological and emotional events operating in the individual, emotions being the most common precipitating factor in epilepsy, then any amelioration of one will raise the convulsive threshold or lower the seizure level (Goldie, 1979; MacCabe & Habovick, 1963). Although 'voluntary control of the alpha rhythm' was achieved over 40 years ago (jasper & Shagass, 1941), only since 1969 has such control been used for clinical purposes (Kamiya, 1969). One striking characteristic of the EEG pattern of many epileptics is the absence of a 12 to 14 c/s rhythm normally recorded from the anterior portions of the brain (sensorimotor rhythm) and the presence of a 4 to 7 c/s rhythm at the same location (Olton & Noonberg, 1980). Biofeedback may enable the individual to increase the amount of sensorimotor rhythm and to decrease the amount of 4 to 7 c/s activity. As a consequence, clinically significant decreases in seizure activity have been found after biofeedback training (Sterman, 1973, 1977). "The present data demonstrate that in this female patient hypnosis induced a highly significant reduction of the interictal activity, concomitant with an increase of alpha and sensorimotor rhythm and a decrease of slow activity, similar to biofeedback but without prior training. " In conclusion, a depth EEG study in one epileptic patient comparing EEG activity during hypnosis and pre- and posthypnosis suggests the following conclusions: (a) hypnosis may be associated with significant decrease of slow activity and an increase of alpha and relatively high frequency, beta activity; (b) electrophysiological correlates of hypnotic behavior support the possible role of the limbic system in mediating the trance experience; and (c) hypnosis is effective in reducing focal interictal abnormalities in this patient and so it can be considered a promising technique to prevent and/or reduce emotional precipitating factors and the tendency to develop seizure activity" (p. 69). The article referenced regarding biofeedback training to reduce ictal activity is: Sterman, M. B. (1973). Neurophysiologic and clinical studies of sensorimotor EEG biofeedback training: some effects on epilepsy. In L. Birk (Ed.), _Biofeedback: Behavioral medicine._ New York: Grune & Stratton, Pp. 147-165. Sterman, M. B. (1977). Effects of sensorimotor EEG feedback training on sleep and clinical manifestations of epilepsy. In J. Beatty & H. Legewie (Eds.), _Biofeedback: Behavioral medicine._ New York: Plenum, 1977, Pp. 167-200. Kissin, Benjamin (1986). Conscious and unconscious programs in the brain. (1 ). New York: Plenum Press. NOTES Hypnosis is discussed in terms of inhibition/excitation mechanisms in the central nervous system, with both feedback and feedforward controls and lateralizing controls. The author employs a concept of engrams (neural representations of an idea, represented throughout the neocortex) to discuss sensation and perception as well as conscious and unconscious processes. Sensory information is processed serially with encoding of information mostly on the conscious level (but sometimes, less efficiently, on the unconscious level); and it also is processed in parallel. Parallel processing operates almost entirely at the unconscious level and is basic to perception. Associative phenomena are explained in terms of overlapping engrams, so that two 'related hypercomplex engrams' could be assumed to have at least one simple engram in common. With Premack, he describes three types of engrams: veridical (primary sensory data perceived), abstract (formalized representations of concepts like line drawings of dog or house; Premack's iconic representations), and symbolic (more complex entities that encompass an entire class of objects, actions, or ideas and may have artificial symbols such as words). With Neiser he suggests that thinking (verbal and nonverbal) involves logical sequential processing of cognitive engrams of external (environmental), internal (visceral),and intracerebral (ideational) origin. Evoked response investigations shed light on the nature of such engrams, their distribution in brain tissue. John, Bartlett, Slumokochi, & Kleiman (1973) found that an error in choice discrimination learning (cats learning colors) is accompanied by the cortical evoked potential of the stimulus associated with that (erroneous) behavior, not the evoked potential of the true stimulus. In other words, ERPs represented the idea, not the actual visual stimulus provided to the cat. Emotional/motivational influences are part of every cognition (R. S. Lazarus's position). Interaction of motivational-emotional and cognitive engrams seems to occur primarily in the inferior temporal lobe and the entorhinal cortex. The interaction involves the upper rhinencephalon, the amygdaloid-hippocampal complex, the septal region, the cingulate gyrus, and the inferior and medial aspects of temporal lobe of the cortex. He also explains classical and operant conditioning (on pp. 75-76) in terms of the association of engrams. The author's position is that consciousness is the subjective equivalent of brain activity in the 'alerting' and 'awareness' systems. Awareness of the environment ('general, vague') appears to involve the limbic area (thalamus and basal ganglia), while more specific awareness of the self entails a system stretching from the basal ganglia through the parietal lobe (posterior aspect). Normal alert consciousness involves the noradrenergic reticular activating system, as well as associated excitation of the general awareness system in the involved thalamic- basal gangliar nuclei and the self-awareness system in the posterior inferior parietal lobe system. Altered states of consciousness characterized by a relaxed hazy sense of the world involves thalamic activation of the self-awareness system. Dreaming involves activation from cholinergic cells in the pons. "Impaired general awareness occurs with lesions of the thalamic-basal gangliar centers while impaired self-awareness occurs with lesions in the posterior inferior parietal lobes. Finally, in certain physiological states such as sleep, hypnosis, and so on, the entire awareness system--the thalamic-basal gangliar and posterior inferior parietal nuclei--may be activated by different activation systems, such as the cholinergic in the pons or the dopaminergic in the thalamus, to produce different states of consciousness" (p. 82). Consciousness is described as having seven dimensions: alertness, attention, arousal (heart rate, GSR), activation (EEG, evoked potential), affect, and the two awarenesses. The seven are related, so that changes in any one usually are correlated with changes in others (though dissociation among the seven also can be demonstrated). Motivational-emotional arousal produces electrophysiological activation of the brain, which is translated epiphenomenally into alertness and awareness; awareness is focused through attention onto the cognitively and motivationally significant events in the internal and external environments to determine the final sequence of drive-oriented behavioral responses. The EEG is useful for diagnosing different states of consciousness: beta and gamma waves alertness, stemming from locus coeruleus and reticular activating system delta (2-4/sec) waves coma alpha synchronized relaxing influences stemming from thalamus; low level of awareness as in twilight sleep or hypnagogic states theta, delta inactivity due to less stimulus from locus coeruleus reticular activating system influences; associated with increased inhibitory thalamic and septal- hippocampal impulses radiating upward to the cortex. In some altered states of consciousness there is theta-wave activity, indicating influences from the inhibitory septal-hippocampal circuit. The reticular activating system (RAS) and thalamus interact in complex ways. The RAS is essential to maintain consciousness, but if destroyed stepwise (in animal research) a low-grade type of consciousness can be maintained by thalamus and basal ganglia. The thalamus has two kinds of influence: it inhibits the cortex, as in sleep; and stimulates the cortex in the form of activating alpha waves. "The median thalamus is also related in a feedforward-feedback circuit with the inhibitory septal-hippocampal complex which generates theta-wave activity, thus accounting for the close association between alpha and theta wave activity in sleep and in other altered states of consciousness" (p. 86). Thus there are two different activating systems originating in the lower brain stem: the norepinephrine locus coeruleus system that is associated with normal behavior, and the cholinergic FTG neurone system of REM sleep. The relationship of the latter to consciousness, awareness, self awareness, etc. is unknown, since the only time that it is readily observed is during REM sleep. The author reports that altered states of consciousness (e.g. hypnosis, fugue, alpha state) resemble Stage 1 sleep, rather than REM sleep, physiologically, with the central locus of activation in the medial thalamus rather than the RAS and locus coeruleus. "It appears then that consciousness may be driven by one or another of three different activation centers: the norepinephrine RAS (emanating from the locus coeruleus), the cholinergic FTG cell system in the pons, and the dopaminergic alpha rhythm system radiating upward from the thalamus (Fig. 6-2). Brain activation by each of these centers is associated with a different state of awareness" (p. 91). The relative contribution from each center determines qualitative aspects of awareness. The author refers to Mesulam and Geschwind (1978) who traced the self- awareness system from amygdala/hippocampus/midbrain to the inferior parietal lobe where they converge with the body's proprioceptive neural tracts. What results is "a sense of self that was not necessarily present in the sense of general awareness stemming from the median thalamic-basal gangliar complex" (p. 97). The thalamic-basal gangliar complex is both a center for emotional reception and a relay station for somatosensory events. Both somatic sensory reception and somatosensory elements of emotion are also represented in the parietal lobe. "Affective and somatosensory stimuli, which are constant and persistent even though we are unaware of them most of the time, produce the sense of one's body which is the most basic element in the 'sense of self.'... It is most probable that a major component of the sense of self is produced by the constant barrage of affective and somatosensory stimuli converging from all parts of the body; the majority of these stimuli may not reach consciousness most of the time but they must register a sense of feeling in the thalamus and parietal cortex even though the individual may be unconscious of it" (p. 100). The author presumes that most of the incoming stimuli that define self are unconscious. "Whether sense-of-self stimuli are unconscious because of constant habituation ... or whether they are unconscious because they are transmitted predominantly to the right hemisphere ..., it appears that the major components of the self- concept are unconscious rather than conscious" (p. 102). "Even the acutely self-aware component of the self-concept, by definition conscious, varies markedly in different altered states of consciousness. The conscious awareness of oneself in the alert condition is different from (1) that in the twilight state, (2) that in dreams, (3) that in hypnosis, (4) that under the influence of alcohol, (5) that under the influence of other sedatives, (6) that under the influence of stimulants, and (7) that under the influence of hallucinogens. In that sense the acute sense of self is a function of the momentary chemical and physiological state of the brain" (p. 102). " ... the decision-making apparatus of the brain is lodged largely in a consortium of neocortical centers including the prefrontal lobes (integration), the posterior inferior lobes (motivation and emotion), the anterior and posterior associational areas (cognition), the posterior inferior parietal lobes (self-awareness), the left-hemispheric language centers (language), and the precentral frontal lobe motor area (motor). Within the context of this integrated cortical complex, self-awareness functions are somewhat stronger on the right hemisphere while language and decisional activities are somewhat stronger on the left" (pp. 102-103). The Chapter titled "Attention as directed consciousness" is relevant for investigations of hypnosis but is not included in these notes. 1985 Banyai, Eva I.; Meszaros, Istvan; Csokay, Laszlo (1985). Interaction between hypnotist and subject: A social psychophysiological approach (preliminary report). In Waxman, David; Misra, Prem C.; Gibson, Michael; Basker, M. Anthony (Ed.), Modern trends in hypnosis (pp. 97-108). New York: Plenum Press. There is a vast amount of literature demonstrating that hypnotic susceptibility is a stable personality trait. In the course of our practice of teaching beginners to hypnotize, however, it occurred to us that hypnotists without sufficient previous training frequently measured a lower level of hypnotic susceptibility than the true score. It has to be emphasized that hypnosis is a special altered state of consciousness which develops as a result of an interaction between a hypnotist and a subject. The failure of beginners to induce hypnosis could be explained by considering an insufficient participation of the hypnotist in this interaction. The purpose of the present study was to analyze the necessary and sufficient subjective, behavioral and physiological alterations in both participants of the hypnotic interaction. During successful and unsuccessful hypnotic inductions the subjective experiences, behavioral manifestations and physiological indicators including respiration, ECG, EMG, EOG, GSR and bilateral fronto- occipital EEG leads, were recorded simultaneously in the hypnotists and the hypnotized subjects. The results indicate that hypnotic induction is successful if a mutual "tuning" of the other person occurs not only on the subjective and behavioral levels, but first of all on the psychophysiological level. Spiegel, David; Cutcomb, Steven; Ren, Chuan; Pribram, Karl (1985). Hypnotic hallucination alters evoked potentials. Journal of Abnormal Psychology, 94 (3), 249-255. Brain electrical potentials evoked by visual stimulation were analyzed to study the neurophysiological mechanism associated with hypnotic hallucination. The visual evoked responses of 6 high- and 6 low-hypnotizable subjects were compared in three hypnotic conditions: stimulus enhancement, stimulus diminution, and stimulus elimination (obstructive hallucination). High-hypnotizable individuals demonstrated significant suppression of the later components of the evoked response (N1 and P3) while experiencing obstructive hallucinations, indicating a change in information processing. This effect was significantly greater in the right, as compared to the left, occipital region. NOTES In the stimulus enhancement condition, Ss were told that one of two colored stimuli would appear unusually bright and interesting. In the stimulus diminution condition, Ss were told that the alternate color stimulus would appear drab, dull, uninteresting. In the obstructive hallucination condition, Ss were told to visualize a box that blocked their view of the TV monitor, making it impossible to see anything on the TV screen. The stimuli were 8 cm x 8 cm squares (colored gratings) presented 1 meter in front of S: 50% were blue vertical gratings, 50% were pink horizontal gratings. Ss were told to press a button in response to any stimulus they happened to see; hence all stimuli were potential targets. To control for the effect of motor potentials when they pressed the button, a button-pressing/passive-attention control group was added. Only results significant beyond this control group were attributed to a hypnotic hallucination effect. A second control group of medium level hypnotizable Ss were required to (a) button press after each stimulus presentation and (b) attend passively to the TV monitor screen without button pressing. "Thus, we had three control conditions: (a) for attentional demands, comparing the performance of high hypnotizables in the obstructive hallucination versus the hypnotic stimulus enhancement condition, (b) for hypnotizability, in comparing the high hypnotizables in the obstructive hallucination condition versus the low hypnotizables in the same condition, and (c) for button-pressing behavior, comparing the performance of the high hypnotizables to that of control subjects in press versus no-press conditions" (p. 250). In their discussion, the authors state, "Our results are consistent with the hypothesis that an hypnotic instruction of obstructive hallucination among high- hypnotizable subjects is accompanied by a decrease in the amplitude of the P3 component of the evoked response throughout the brain, and of the N2 and P3 components in the occipital region. This dampening of amplitude is particularly notable among high hypnotizables in the right, as compared with the left, occipital area, suggesting greater inhibition of scalp-recorded response to a visual stimulus in the right hemisphere. "These data show that while experiencing an obstructive hallucination blocking the stimulus, high-hypnotizable subjects demonstrate a change in the information-processing components of the evoked response (Baribeau-Braun, Picton, & Gosselin, 1983), rather than primarily in channel selection, which is reflected more by P1 and N1 (Ford, Roth, Dirk, & Kopell, 1978; Hillyard & Picton, 1979). Although there were differences at P1 and N1 between high and low hypnotizables, they were not significantly greater than those observed in the press/no-press control group. These observations make it possible to address several alternative explanations for the findings, such as the possibility of differences in nonspecific arousal leading to a differential preparation (Naatanen, 1969), which should be reflected primarily in changes in the early components, as would any differences in pupil size. Drowsiness or inattention in this condition should be associated with an increase, rather than a decrease, in response amplitudes (Schacter, 1976). The possibility that high hypnotizables might have defocused their view of the monitor (Schulman-Galambos, & Galambos, 1978) is made less likely by the fact that defocusing is accompanied by increases in P1 latency (Sokol & Moskowitz, 1981), whereas there were no P1 latency differences in the obstructive hallucination condition" (p. 254). 1984 Cocores, James A.; Bender, Andrew L.; McBride, Eugene (1984). Multiple personality, seizure disorder, and the electroencephalogram. Journal of Nervous and Mental Disease, 172, 436-438. Used the EEG to study multiple personality in a 48-yr-old ambidextrous male admitted for alcohol detoxification and individual psychotherapy. Despite conflicting reports in the literature, no changes in the EEG were found that could not be ascribed to the normal changes seen in transitions from various states of alertness. The problems of differentiating multiple personality as a psychiatric entity in itself from those cases arising as a result of chronic partial or partial-complex epilepsy are discussed. Gott, Peggy S.; Hughes, Everett C.; Whipple, Katherine (1984). Voluntary control of two lateralized conscious states: Validation by electrical and behavioral studies. Neuropsychologia, 22 (1), 65-72. A subject is described who can voluntarily select and hold either of two qualitatively different states of consciousness. Evidence is presented which confirmed differential left or right hemisphere dominance in each state. Asymmetries of EEG alpha and task performance scores indicated a state-dependent shift in functional lateralization. Evoked response studies showed directional changes in rate of interhemispheric transmission correlated with state-related hemisphere dominance. These findings demonstrated the capability for voluntary endogenous control of cerebral dominance under natural conditions. NOTES A personal communication (letter) from Gott indicates the S switches from one state to the other by visualizing her surroundings and imagining what it would look like in the other state. Immediately she finds herself in that other state. Her drawings demonstrate that her perspective must differ in the two states. La Briola, Flora; Karlin, Robert; Goldstein, L. (1984, October). Quantitated EEG changes from prehypnotic to hypnotic periods. [Paper] Presented at the annual meeting of the Society for Clinical and Experimental Hypnosis, San Antonio, TX. NOTES Hemisphere EEG activation was measured before and during hypnosis, while Ss did tasks described as right-hemisphere (nonverbal) and left hemisphere (verbal). Highs shifted to relatively more task specificity as they went from prehypnosis into hypnosis, with a shift to right hemisphere as they went from prehypnosis to hypnosis periods. This is not due to relaxation, as both highs and lows relax. And the shift occurs not only on verbal-nonverbal tasks but on analgesia studies also. Versions of this paper were presented at the 93rd Annual Meeting of the American Psychological Association, Toronto, Canada, 1984, at the Annual Meeting of the Society for Clinical and Experimental Hypnosis, San Antonio, TX, 1984, and at the 6th International Symposium on Clinical Neurophysiological Aspects of Psychiatric Colnditions, Izmir, Turkey, 1985. 1983 Borgeat, Francois; Goulet, Jean (1983). Psychophysiological changes following auditory subliminal suggestions for activation and deactivation. Perceptual and Motor Skills, 56, 759-766. This study was to measure eventual psychophysiological changes resulting from auditory subliminal activation or deactivation suggestions. 18 subjects were alternately exposed to a control situation and to 25-dB activating and deactivating suggestions masked by a 40-dB white noise. Physiological measures (EMG, heart rate, skin-conductance levels and responses, and skin temperature) were recorded while subjects listened passively to the suggestions, during a stressing task that followed and after that task. Multi-variate analysis of variance showed a significant effect of the activation subliminal suggestions during and following the stressing task. This result is discussed as indicating effects of consciously unrecognized perceptions on psycho- physiological responses. Nash, John (1983). Negative visual hallucination and concomitant changes in cortical event-related potentials (Dissertation, University of California, Santa Barbara). Dissertation Abstracts International, 45 (2), 716-B. (Order No. DA 8411224) The purpose of this investigation was to examine the effects of negative visual hallucination (NVH) on cortical event-related potentials (ERPs), and to compare these effects with those of selectively attending to and ignoring stimuli. Five highly hypnotically susceptible subjects, four female and one male, were trained to block from subjective experience, i.e., negatively hallucinate, a ring of strobe-illuminated circles surrounding a central, independently strobe-illuminated circle. This stimulus array was modeled after part of the Titchener-Ebbinghaus circle illusion, since previous research had shown that subjects could attenuate the effects of the optical illusion via NVH of the outer, illusion-producing circles. "Analysis of the ERP data revealed amplitude and latency changes in various ERP components across the three experimental conditions (Attend, Ignore, NVH) for the four female subjects, a negative result which is explained in motivational terms. "The most noteworthy finding was the selection of the P3 amplitude variable at C2 by stepwise discriminant analysis for the four females, and the fact that this amplitude systematically decreased across conditions from largest in Attend to smallest in NVH. A variety of individual patterns were observed in terms of other ERP components which allowed discrimination (successful classification) among the three conditions. The results suggest that both Ignoring and NVH of a stimulus result in a decrease in the subjective certainty of perception of the stimulus. Individual differences in patterns of ERP changes are interpreted in terms of differing strategies for execution of the experimental instructions. The results support the view that NVH instructions produce distinctive ERP effects and that NVH generally can be viewed as an extreme level of ignoring" (p. 716). 1982 Barabasz, Arreed F. (1982). Restricted environmental stimulation and the enhancement of hypnotizability: Pain, EEG alpha, skin conductance and temperature responses. International Journal of Clinical and Experimental Hypnosis, 30, 147-166. Restricted environmental stimulation procedures were used with 10 Ss. The Stanford Hypnotic Clinical Scale: Adult, modified to include a posthypnotic suggestion for an analgesic reaction, and pain threshold and tolerance tests were administered prior to restricted environmental stimulation technique (REST), immediately after REST, and 10-14 days later. Occipital EEG alpha, skin conductance, and peripheral, core, and chamber temperature data were collected prior to, during, and after REST. A control group of 10 Ss was used to assess the effects of repeated hypnosis upon susceptibility scores and demand characteristics of the experiment. Multivariate analysis of variance results showed SHCS and pain tolerance scores to be significantly enhanced for Ss exposed to REST immediately after and 10-14 days later. Orne's (1959) postexperimental inquiry technique did not reveal experimental demand characteristics which might account for the results. EEG alpha density increased significantly in REST, but the increase was not progressive during the REST period. The maintenance of hypnotizability and pain tolerance at follow-up failed to support Reyher's (1965) theory of brain function and behavioral regulation. E. R. Hilgard's (1977) neodissociation interpretation combined with J. R. Hilgard's (1974, 1979) imaginative involvement findings is viewed as a possible explanation. Blum, Gerald S.; Nash, John K. (1982). EEG correlates of posthypnotically controlled degrees of cognitive arousal. Memory and Cognition, 10, 475-478. Experimental control over five degrees of cognitive (as opposed to organismic) arousal has been developed by hypnotic programming techniques. Previously these posthypnotic manipulations have been applied to the investigation of diverse topics such as visual discrimination, performance on the Stroop test, selective concentration on color versus form of consonants, and cognitive "reverberation." The present study explored EEG correlates of the five degrees of cognitive arousal in a task requiring participants to visualize objects for one-minute periods while lying on a couch with eyes closed. Analysis of data from the occipital area in left and right hemispheres revealed that the highest degree of arousal was accompanied by larger amplitudes of alpha and beta power and smaller amplitudes of theta. This pattern of results was similar in both hemispheres, although more marked in the left. The findings, which provide an independent source of support for validity of the hypnotic programming, are discussed in relation to EEG literature on cognitive activity. NOTES Hypnosis doesn't enhance imagery. It provides the conditions under which mental alertness may be manipulated, and very clear imagery is associated with the alert condition whereas blurry imagery is associated with the lowest cognitive arousal condition. The other impression comes from clinical work, i.e. that hypnosis enhances imagery. This article is an example of hypnosis used in other research--see last page. Cutcomb, Steven Donald (1982, May). Studies in the brain correlates of human cognitive function (Dissertation, Stanford University). Dissertation Abstracts International, 42 (11), 4609-4610-B. Three studies in the electrophysical correlates of human cognitive function are described. In study one, colored gratings were presented tachistoscopically to humans in two selective attention paradigms based upon the design of Hansen and Hillyard (1980), and Hillyard, Hink, Schwent, and Picton (1973). Visual event-related potential (ERP) data from Fz, Cz, Pz, T5, T6, O1, and O2, and behavioral responses were collected, and averaged ERPs were subjected to feature extraction (P1, N1, P2, N2, and P3 amplitudes and latencies) as well as a principle components factor analysis. Both analyses revealed as a significantly larger N2 component in the visual ERP, peaking at 310 msec and maximally frontally, during attending to task-relevant (attended-channel) stimuli. The P3 component was significantly larger in response to all attended-channel stimuli. In study two, the task was repeated using a group of six high and six low susceptible subjects during hypnosis. ERPs from Fz, Cz, Pz, O1, and O2, and behavioral responses were recorded during the task, and during a hypnotic suggestion of a negative hallucination (obstructed view of the stimulus monitor) while the stimuli were presented. The averaged ERP data was subjected to feature extraction followed by analyses of variance. No inter-group differences were found in the ERPs during the selective attention tasks. "During the obstructed view suggestion, the lows showed a normal visual ERP, while the highs had a visual ERP with a significantly diminished P1, P2, N2, and P3 component amplitude at O1 and O2. These results are evidence for an altered brain response during the obstructed view suggestion in high susceptible hypnotized subjects. "In study three, EEG were recorded from twelve high and twelve low susceptible hypnotic subjects (frontal, central, occipital) during baseline and hypnotized conditions. Data were transformed to normalized theta and alpha-band power spectral averages for each group. No significant inter-group alpha differences were found. Highs had significantly more relative theta energy frontally. During hypnotic tasks, the highs showed higher relative theta power at all leads. These results are consistent with the trait conception of hypnotic susceptibility" (pp. 4609-4610). Larbig, W.; Elbert, T.; Lutzenberger W.; Rockstroh, B.; Schnerr, G.; Birbaumer, N. (1982). EEG and slow brain potentials during anticipation and control of painful stimulation. Electroencephalography and Clinical Neurophysiology, 53, 298-309.