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PubMed1988

Drinking practices among black and white alcoholics and alcoholics of different personality types.

In order to examine the effects that race and personality type have on self-reported drinking practices, samples of 49 White and 49 Black male alcoholics were matched on age and education, and classified into two personality types according to MMPI scores. The results of multivariate and univariate analyses of variance yielded significant main effects. White alcoholics reported a greater: (a) use of alcohol for symptomatic relief of psychological distress, (b) loss of motor control and tendency to engage in destructive acts, and (c) daily consumption of beverage alcohol than Black alcoholics. Alcoholics with psychiatric-appearing MMPI profiles reported greater: (a) social benefits of alcohol use, (b) alcohol use for symptomatic relief of psychological distress, and (c) perceptual distortions associated with alcohol withdrawal than alcoholics with characterlogical-appearing MMPIs. Results were discussed in terms of need to control confounding effects of biosocial variables in cross-cultural research and implications that these effects may have on the generalizability of alcoholic personality typologies.

Adult↗
PubMed1992

Toward the clarification of the construct of depersonalization and its association with affective and cognitive dysfunctions.

Little consensus or systematic research exists regarding the symptoms that constitute depersonalization and its association with affective and perceptual dysfunctions. A scale was constructed to measure depersonalization experiences reported in the literature and four items representing psychotic symptoms. Five factors representing different types of depersonalization emerged: Inauthenticity, Self-Negation, Self-Objectification, Derealization, and Body Detachment. Based on the factors, scales were constructed; these scales have internal consistency ranging from .78 to .84. Each of these factor scales was factorially distinguishable from psychosis and correlated between .48 and .58 with the Jackson and Messick (1972) Feelings of Unreality Scale, suggesting divergent and convergent validity. Inauthenticity, the most frequent and pervasive form of depersonalization experience, was best predicted by a cognitive style featuring intense, critical examination of self and others. In contrast, Self-Objectification was best predicted by thought disorganization and perceptual distortion and was experienced somewhat infrequently by relatively few subjects. All forms of depersonalization were associated with depression, except Inauthenticity.

Adult↗
PubMed2005

Control theory and psychopathology: an integrative approach.

Perceptual control theory (PCT; Powers, 1973) is presented and adapted as a framework to understand the causes, maintenance, and treatment of psychological disorders. PCT provides dynamic, working models based on the principle that goal-directed activity arises from a hierarchy of negative feedback loops that control perception through control of the environment. The theory proposes that psychological distress arises from the unresolved conflict between goals. The present paper integrates PCT, control theory, and self-regulatory approaches to psychopathology and psychotherapy and recent empirical findings, particularly in the field of cognitive therapy. The approach aims to offer fresh insights into the role of goal conflict, automatic processes, imagery, perceptual distortion, and loss of control in psychological disorders. Implications for psychological therapy are discussed, including an integration of the existing work on the assessment of control profiles and the use of assertive versus yielding modes of control.

Behavior↗
PubMed1984

When alcoholics are not anonymous: socioperceptual effects of labeling and drinking pattern.

The influence of the label "alcoholic" on observers' social perceptions and behavioral intentions about peers who consume alcohol normatively or excessively was examined. College students (40 men and 40 women) listened to a tape-recorder bogus interview in which a male interviewee reported either a normative or an excessive drinking pattern after having or ot having been labeled an alcoholic by the experimenter. Subjects then rated their reactions to the interviewee on several dimensions. Relative to the normative drinker, the excessive drinker was more likely to be judged by both sexes as deviant, an alcoholic, not in control of his drinking, poorly adjusted, psychologically ineffective, unlikely to improve, in need of professional help and responsible for this behavior, and was more strongly rejected as a potential friend and co-worker. The label of "alcoholic" negatively affected nearly all these perceptions at each level of alcohol use but without perceptual distortion of the interviewees' amount of consumption. The implications for the contribution of interpersonal stigma to alcohol-related problems are discussed.

Adolescent↗
PubMed2002

The formation of linked perceptual classes.

Multiple-exemplar training with stimuli in four domains induced two new fill-based (A1' and A2') and satellite-image-based (B1' and B2') perceptual classes. Conditional discriminations were established between the endpoints of the A1' and B1' classes as well as the A2' and B2' classes. The emergence of linked perceptual classes was evaluated by the performances occasioned by nine cross-class probes that contained fill variants as samples and satellite variants as comparisons, along with nine other cross-class probes that consisted of satellite variants as samples and fill variants as comparisons. The 18 probes were first presented serially and then concurrently. Class-consistent responding indicated the emergence of linked perceptual classes. Of the linked perceptual classes, 70% emerged during the initial serial test. An additional 20% of the linked perceptual classes emerged during the subsequently presented concurrent test block. Thus, linked perceptual classes emerged on an immediate or delayed basis. Linked perceptual classes, then, share structural and fuctional similarities with equivalence classes, generalized equivalence classes, cross-modal classes, and complex maturally occurring categories, and may clarify processes such as intersensory perception.

Adolescent↗
PubMed2002

The formation of a generalized categorization repertoire: effect of training with multiple domains, samples, and comparisons.

The present experiment explored the effects of three variables on the spontaneous categorization of stimuli in perceptually distinct and novel domains. Each of six stimulus domains was created by morphing two images that were the domain endpoints. The endpoints of the domains were male and female faces, two abstract drawings, a car and a truck, two banded-elevation satellite land images, a tree and a cat, and two false-color satellite images. The stimulus variants at each end of a domain defined two potential perceptual classes. Training was conducted in a matching-to-sample format and used stimuli from one or two domains, one or three variants per class as samples, and one or three variants per class as comparisons. The spontaneous categorization of stimuli in the untrained stimulus domains showed the emergence of a generalized categorization repertoire. The proportion of spontaneously categorized stimuli in the new domains was positively related to the number of domains and samples used in training, and was inversely related to the number of comparisons used in training. Differential reaction times demonstrated the discriminability of the stimuli in the emergent classes. This study is among the first to provide an empirical basis for a behavior-analytic model of the development of generalized categorization repertoires in natural settings.

Adolescent↗
PubMed1991

The Defense Mechanism Test in nonpsychotic psychiatric outpatients and normal controls.

In the Defense Mechanism Test, stimuli representing a central figure threatened by a peripheral person are presented tachistoscopically, at increasing exposure times. The threat is assumed to trigger defense mechanisms that are expressed by several types of perceptual distortions. Given that to date no experimental study has validated the discriminative power of the Defense Mechanism Test between normal controls and clinical groups, 99 normal controls and 57 nonpsychotic psychiatric outpatients were given the test. Significantly more psychiatric patients than controls were coded for presence of each of the ten main defensive signs of the Defense Mechanism Test (with a peak significance for reaction formation). Ten codings or subcodings of defense which were particularly rare in the control sample were employed to discriminate between groups. This procedure correctly allocated 85.8% of the control subjects and 85.9% of the psychiatric patients. The present findings allow a preliminary distinction between codings of defense with questionable, moderate, or strong clinical significance, in the area of nonpsychotic psychopathology.

Adult↗
PubMedDate not supplied

The perception of rorschach inkblots in schizophrenia: a neural network model.

Schizophrenia is a psychiatric disorder characterized by a variety of cognitive deficits, including perceptual distortions and hallucinations. In recent years several studies have proposed that schizophrenia may involve a disturbance of "context". We have used a three layer neural network model constructed from an input layer followed by two computational layers to simulate responses of schizophrenic patients to the Rorschach test. In this test subjects respond to a set of ambiguous patterns created by ink blots on paper. Our model proposes that a disturbance of context caused by altered noise-to-signal ratio at the level of the single units, is responsible for schizophrenic responses to the Rorschach test. The assumption that catecholaminergic neurotransmitter systems regulate noise-to-signal ratio in cortical neurons constitutes a link between findings of altered neurotransmitter activity and deficits of cognitive functions requiring contextual integration in schizophrenia. The development of models for specific task deficits in schizophrenia could advance our insights regarding the neurological mechanisms underlying serious mental disorders such as schizophrenia.

Humans↗
PubMed1993

Toward a comparative overview of dependence potential and acute toxicity of psychoactive substances used nonmedically.

A procedure is outlined for comparing dependence potential and acute toxicity across a broad range of abused psychoactive substances. Tentative results, based on an extensive literature review of 20 substances, suggested that the margin of safety ("therapeutic index") varied dramatically between substances. Intravenous heroin appeared to have the greatest risk of dependence and acute lethality; oral psilocybin appeared to have the least. Hazards due to behavioral deficits, perceptual distortion, or chronic illness were not factored into the assessments.

Humans↗
PubMed2004

Perspective distortion of trajectory forms and perceptual constancy in visual event identification.

Previous studies have shown that people can use the information in trajectory forms to recognize visual events. A trajectory form is composed of the path of motion and the change in speed along that path. In past studies, however, only sensitivity to trajectory forms viewed from a single perspective was examined. The optical components change when an event is viewed from different perspectives, and the projected form of the trajectory is transformed. Does event recognition exhibit constancy despite these changes? In Experiment 1, participants were familiarized with five different trajectory forms viewed from a single perspective. Then the participants had to identify the same events viewed from different perspectives: from the side, at an angle, and entirely in depth. The participants exhibited perceptual constancy. Experiment 2 revealed, however, that both the change in optical components and the perspective transformations affected recognition.

Feedback↗
PubMed1996

Effects of high-pass and low-pass spatial filtering on face identification.

If face images are degraded by block averaging, there is a nonlinear decline in recognition accuracy as block size increases, suggesting that identification requires a critical minimum range of object spatial frequencies. The identification of faces was measured with equivalent Fourier low-pass filtering and block averaging preserving the same information and with high-pass transformations. In Experiment 1, accuracy declined and response time increased in a significant nonlinear manner in all cases as the spatial-frequency range was reduced. However, it did so at a faster rate for the quantized and high-passed images. A second experiment controlled for the differences in the contrast of the high-pass faces and found a reduced but significant and nonlinear decline in performance as the spatial-frequency range was reduced. These data suggest that face identification is preferentially supported by a band of spatial frequencies of approximately 8-16 cycles per face; contrast or line-based explanations were found to be inadequate. The data are discussed in terms of current models of face identification.

Adult↗
PubMed1995

Combining image degradations in a recognition task.

Six experiments are reported that investigate the effect on form recognition performance of combining three kinds of stimulus degradations: local area averaging of intensities, low-pass spatial frequency filtering, and random dot visual interference. The effects are shown to be more complicated than previously reported in simple demonstrations. The complexity of the results suggests that models based on single stimulus attributes such as energy or spatial frequency spectrum probably cannot account for the data. Eclectic theories that invoke combinations of redundant processes may be necessary for describing visual recognition phenomena, even within the limited domain examined in this study.

Adult↗
PubMed2000

Behind bars: personality disorders.

Individuals with severe, function-impairing personality disorders comprise a large proportion of the difficult-to-manage inmates. Personality disorders are reliably diagnosable using standardized criteria (DSM-IV), and treatment options are now available. Through careful assessment, differential diagnosis, and differential therapeutic selection, clinicians have the opportunity to help these individuals gain more control over unstable affect, impulsive/ irritable aggression, and paranoid perceptual distortions. Appropriate intervention holds the possibility, if not the promise, of reduced morbidity and recidivism, and may reasonably contribute to the public safety mission of corrections and to the primary mission of clinicians, which is improved health.

Behavior Therapy↗
PubMed2001

Current management of opioid-related side effects.

The optimal management of opioid-related side effects is hampered by a lack of comparative studies of management strategies. The prevalence of such side effects is influenced by the extent of disease, the patient's age, the presence of coexistent renal and hepatic disease, pulmonary disease, and cognitive dysfunction, a prior opioid history, use of polypharmacy, dose of opioid drug being administered, and the route of administration. The most common opioid-related side effects are constipation, sedation, nausea, vomiting, and cognitive disturbance. Less frequent side effects include urinary retention, perceptual distortion, respiratory depression, and myoclonus. In an era emphasizing quality of life in cancer care, clinicians need to be aware of (1) factors that influence the prevalence of opioid-related side effects, (2) effective management strategies, and (3) how to recognize when symptoms are opioid related as opposed to caused by other etiologies, such as the patient's disease process or treatment approaches. The use of validated instruments and repeated assessment enhances such an evaluation and subsequent treatment. This article delineates the current optimal management of opioid-related nausea and vomiting, constipation, cognitive side effects, myoclonus, and respiratory depression.

Analgesics, Opioid↗
PubMed1975

Learned helplessness, depression, and anxiety.

The learned helplessness model of depression predicts that depressives should tend to perceive reinforcement as response-independent in skill tasks. Depressed-anxious, nondepressed-anxious, and nondepressed-nonanxious college students estimated their chances for success in a skill or a chance task. (Virtually no depressed-nonanxious subjects could be obtained.) Depressed-anxious subjects showed less expectancy change in skill than nondepressed-anxious subjects, while these two groups exhibited similar expectancy change in chance. Nondepressed-anxious and nondepressed-nonanxious subjects did not differ in either skill or chance. The results for a discrimination learning problem were mixed. The groups did not differ in latency to shut off an aversive noise. So, depressed subjects perceptually distort the outcomes of skilled responding as being response-independent, and they may, under certain conditions, show deficits at learning the consequences of responses. These deficits may reflect learned helplessness and are specific to depression.

Anxiety↗
PubMed1964

[REVIEW OF PSYCHODYSLEPTICS: I. CLASSIFICATION OF PSYCHODYSLEPTICS].

The discovery of new dysleptic drugs has prompted the present review of these substances which influence neuropsychic activity. It is possible to divide dysleptics into two categories: under the first heading fall mescaline, LSD-25, psilocybine, adrenochrome, bufotenine and dimethyltryptamin; the other group includes Ditran, Butoxamine, WH-4849, and AHR-379. The place of Sernyl could not be ascertained and it might well constitute a class by itself. The mescaline type of reaction is mainly characterized by the induction of perceptual distortions without alteration of the state of consciousness, whereas the Ditran type reaction is one of confusion with postexperimental amnesia. Electroencephalographic recordings support this classification: lowering of amplitude, acceleration of rhythm and desynchronization were noted with the first group; and slowing of rhythm and slow waves similar to those seen during the onset of sleep, with the other group.

Adrenochrome↗