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G S Blum

Publications and source records attributed to G S Blum.

At least 19 recordsLinked to original sources

A computer model for unconscious spread of anxiety-linked inhibition in cognitive networks.

Unconscious inhibitory processes, triggered by a potential anxiety reaction, are reviewed in the context of an emerging rapprochement between psychodynamic and cognitive approaches in experimental psychology. Conditions underlying spread of inhibitory action to other cognitive networks are first explored in three tachistoscopic experiments utilizing words posthypnotically tied to a potential anxiety, pleasure, or neutral reaction. Response times of subjects, instructed to ignore those words while naming pictures or solving anagrams as quickly as possible, reveal a highly differentiated pattern of circumstances governing likelihood of inhibitory spread from anxiety-linked words to target stimuli. Next a computer model is constructed to simulate cognitive processes from onset of display to eventual response, and the model is then tested for its fit to the empirical data. Finally, an illustrative study shows that a subset of computer-generated predictions for spread of inhibitory action is verifiable experimentally.

Adult↗

Attentional alterations of slant-specific interference between line segments in eccentric vision.

Slant-specific interference between line segments in eccentric vision was altered by attentional methods in hypnotically susceptible observers. These methods included negative and positive posthypnotic hallucination of the inducing elements of the array, and nonhypnotic instruction to actively ignore the elements. Contributions to the experimental effects apparently derived in part from intrinsic inhibitory or facilitatory skill in the individual observer, sharpened by hypnotic training in hallucinations. Control observers with low and with high hypnotic susceptibility were not able to alter significantly the interference effect when attempting to simulate the hallucination conditions. The results seemingly link these attentional alterations to an early cortical stage of visual processing.

Adolescent↗

Effects of posthypnotic suggestion on perceived egocentric distance.

The effects of posthypnotic suggestion on the perception of egocentric distance were evaluated by two methods, one direct and the other indirect. The direct method was the verbal report of the perceived distance of the stimulus. The indirect method used a measure based on apparent concomitant motion of the stimulus with a lateral movement of the head. The indirect method, unlike the direct method, has been shown to be insensitive to cognitive biases. Two highly trained hypnotic observers received posthypnotic suggestions to see a point of light at approximately 2, 4, or 6 ft (61, 122, or 183 cm) from themselves. For each suggested distance the light was physically at 2, 4, or 6 ft. As a control, trails were completed using these same physical distances without the posthypnotic suggestions. Nine experimental trails, one for each combination of suggested distance and physical distance, constituted a trial set. One observer completed three sets, and the other completed two sets. It was found that the posthypnotic suggestions affected the direct but not the indirect measures of the perceived distances of the light.

Adolescent↗

Selective inattention to anxiety-linked stimuli.

The term selective inattention as used here subsumes those phenomena whose primary function is the active blocking or attenuation of partially processed contents en route to conscious expression. Examples are anxiety-motivated forgetting or perceptual distortion and hypnotically induced negative hallucinations. Studies in the field of selective attention have typically been designed to explain what takes place in a task in which the subject is first instructed to attend to a particular stimulus and then to consciously execute that instruction as well as he can. The rejection of content in process is examined only sceondarily as a consequence of the acceptance of relevant information. In the present experiments and theorizing, the emphasis instead is on inhibitory operations that take place automatically, without conscious intent, in response to a potential anxiety reaction. Experiment 1 explored the interaction of anxiety-linked inattention with strength of a target stimulus. Three female subjects were programmed under hypnosis to respond posthypnotically in the On condition with prescribed degrees of anxiety when certain Blacky pictures popped into mind later ,t the end of experimental trials; in the Off conditionall pictures were to become neutral. With the three female subjects still under hypnosis, each of the loaded pictures was then paired with a four-letter work relevant to the individual's own version of what was happening in the picture. The waking recognition task, carried out with amnesia for the prior hypnotic programming, consisted of tachistoscopic exposure of loaded words and physically similar filler words at four durations within a baseline range of recognition accuracy from 50%--75% correct. The data yielded a curvilinear relationship in which the recognition of only the loaded words was significnatly lower in the On condition at the 60%--70% range of recognition accuracy but not at shorter or longer stimulus durations. Experiment 2, for which the prior hypnotic programming of the same three subjects was similar to Experiment 1, used an anagram approach to comparable four-letter words, except that pleasure-loaded words were introduced as a control along with filler words. Four durations of tachistoscopic exposure of the anagrams were used with each individual, and the major dependent variable was response latency measured in milliseconds. An independent measure of perceptual discriminability of the scrambled stimulus letters was obtained to isolate perceptual from cognitive aspects of the task. The results indicated that both low perceivability and high solvability increase the likelihood of response delays specifically in the presence of anxiety-linked stimuli. Experiment 3 was a nonhypnotic replication of Experiment 2, using 12 male and 13 female subjects. The potential affective loading of key anxiety and pleasure words was accomplished by structured scenarios for the Blacky pictures in which subjects were asked to place themselves as vividly as possible...

Adult↗

The effects of mood upon imaginal thought.

The effects of mood upon imaginal thought were explored with a highly trained undergraduate female hypnotic subject. She was hypnotically programmed to experience free-floating anxiety or pleasure in varying degrees just before the exposure of combinations of three Blacky Pictures, and to produce dreamlike imagery in response to the Blacky stimuli while under sway of the mood. Data from 98 dream trials, separated by amnesia, indicated that the affective states clearly influenced imaginal processes. Blind ratings by a psychoanalyst showed the anxiety moods to be more closely associated with primary-process features characteristic of nocturnal dreams, whereas pleasure had a relatively higher incidence of daydreamlike ratings. Empirical analysis of themes yielded significant relationships of anxiety to physical injury to the self and verbal aggression toward others; pleasure was associated with circular movements and overt sex themes.

Journal Article↗

The effects of mood upon imaginal thought.t.

The effects of mood upon imaginal thought were explored with a highly trained undergraduate female hypnotic subject. She was hypnotically programmed to experience free-floating anxiety or pleasure in varying degrees just before the exposure of combinations of three Blacky Pictures, and to produce dreamlike imagery in response to the Blacky stimuli while under sway of the mood. Data from 98 dream trials, separated by amnesia, indicated that the affective states clearly influenced imaginal processes. Blind ratings by a psychoanalyst showed anxiety moods to be more closely associated with primary-process features characteristic of nocturnal dreams, whereas pleasure had a relatively higher incidence of daydreamlike ratings. Empirical analysis of themes yielded significant relationships of anxiety to physical injury to the self and verbal aggression toward others; pleasure was associated with circular movements and overt sex themes.

Adult↗