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Pigeons' not pecking or pecking constituted choice between a delayed, large reinforcer and an immediate, small reinforcer (self-control) and at other times between a delayed reinforcer and no reinforcer (omission). Both a tone and a keylight were tested as choice signals, and the delayed reinforcer was either response independent or response dependent. Pigeons pecked during the choice signals on over 95% of the trials in the self-control procedure, and pecked during the choice signals on over 75% of the trials in the omission procedure. Consistent pecking was observed with either the tone or the keylight as a choice signal, with the exception that a tone paired with a response-independent delayed reinforcer did not maintain pecking in the omission procedure. Pigeons pecked during more choice signals when delayed reinforcers were response dependent than when the delayed reinforcers were response independent. These results indicate that Pavlovian conditioning influences self-control experiments, especially in single-key procedures. 相似文献
104.
Two perspectives on the nature of the social group and psychological group formation are discussed. The traditional social cohesion approach traces group formation to processes of interpersonal attraction, while the social identity approach defines the group in cognitive terms and considers identification, or self-categorization, to be the mechanism of psychological group formation. On the basis of an experiment by Turner, Sachdev and Hogg (1983) it is hypothesized that interpersonal attraction (positive or negative) is related to group formation only in so far as it enhances intergroup distinctiveness. This hypothesis is experimentally tested in a 2 × 3 (interpersonal liking/disliking per se versus no explicit categorization/random categorization/criterial categorization on the basis of affect) factorial design employing the ‘minimal group’ paradigm. People who like each other and were not explicitly categorized formed a group. This effect was enhanced by criterial categorization but disappeared when categorization was random. Although the results do not support the hypothesis, they are not explicable in social cohesion terms. A social identity explanation is furnished—attraction influences group formation by acting, under certain specifiable conditions, as a cognitive criterion for common category membership. This explanation is located in current theorizing and is proposed as part of a reconceptualization of the relationship between interpersonal attraction and group formation. 相似文献
105.
In an attempt to investigate the range effect obtained by Moyer and Bayer (1976), two groups of subjects were taught to associate colors with circles that differed in size by larger or smaller intervals and then participated in a symbolic comparison task, in which they determined which of two simultaneously presented symbols (the first letters of two colors) represented the larger magnitude. A third group of subjects, who merely learned an arbitrary ordering of the colors along the dimension of size, also participated in the symbolic comparison task. Despite the fact that no practice trials were given, there was no effect of interval size in either early or late blocks, and the circle-learning groups did not differ in performance from the group who only learned an arbitrary ordering of colors, even when pairs containing end terms were removed from the analysis. It is concluded that subjects do not use analogue codes in symbolic comparison tasks involving small, repeated sets of arbitrarily defined symbols. 相似文献
106.
John B. Jemmott III 《Journal of personality》1987,55(2):267-298
This article reviews studies on the relation between social motives and susceptibility to physical illness. The motives examined in the studies include power motivation and affiliation motivation and their related syndromes such as inhibited power and relaxed affiliation. The subject populations include college students as well as adults. Blood pressure, self-reports of illnesses, catecholamines, and parameters of immunologic functioning are among the indices of health outcomes investigated. Taken together, these studies suggest that social motives may be importantly related to susceptibility to illness, that the power motive may be related to heightened susceptibility to illness, particularly when the person is under stress, whereas the affiliation motive may be related to diminished susceptibility to illness. 相似文献
107.
Certification is the process whereby older juveniles who have committed felony offenses are transferred from juvenile courts to adult courts. The present study examined the variables that influence decisions in these cases and used attribution theory to conceptualize the process. Data were obtained from files of 150 youths on whom certification petitions had been filed from January 1981 to October 1984. Of these, 125 had been certified and 25 had not. The sample comprised 148 males and 2 females. Data included seriousness of the offense, previous offenses, potential for aggressiveness, level of involvement in the offense, age, court in which the case was heard, year in which the case was heard, IQ, family income and sex. Level of involvement, seriousness of the offense and potential for aggressiveness had the strongest association with certification outcomes, with those high on these measures significantly more likely to be certified. The cluster that predicted outcomes best included level of involvement, seriousness of the offense, potential for aggressiveness, IQ, year in which the case was heard, court in which the case was heard, sex and previous offenses. The most explicitly behavioral variable—how actively the child participated in the offense—was the best single predictor of outcomes. 相似文献
108.
Mark H. Lewis Alfred A. Baumeister Richard B. Mailman 《Journal of applied behavior analysis》1987,20(3):253-258
A perceptual reinforcement theory of stereotyped movements is advanced by Lovaas, Newsom, and Hickman (1987) in an effort to integrate a number of diverse observations about the origins and maintenance of this behavior. We, in turn, argue that the theory, as presented, is logically flawed and fails to take into account important biological findings and theory concerning pathological stereotyped acts. An alternative theory, derived primarily from neurological concepts, is briefly described. 相似文献
109.
The effects of anxiety management training were evaluated by allocating 66 generally anxious clients to either a wait list condition, non-directive counselling, or a combination of relaxation and brief cognitive therapy. Anxiety management was significantly more effective than the wait list condition on a number of relevant measures at post-treatment, but there were relatively few differencs between anxiety management and non-directive counselling, either at post-treatment or at 6 months follow-up. Those differences which were found could plausibly be explained in terms of the demand characteristics of training in relaxation or cognitive therapy. It was concluded that anxiety management is clearly better than a non-treatment control condition, but that its superiority to plausible alternatives which lack the specific components thought to be responsible for improvement has yet to be demonstrated. 相似文献
110.
Sex differences in spatial task performance of patients with and without unilateral cerebral lesions 总被引:2,自引:1,他引:1
Two visuospatial tasks, the WAIS Block Design and the Street Gestalt Completion Test, were administered to men and women with and without unilateral cerebral lesions. These two tasks represent different categories of visuospatial functions. The Street test is a visual-perceptual gestalt task, requiring the closure of fragmented pictures, whereas Block Design is an analytical, manipulospatial task requiring rotation of spatial coordinates. For the non-brain-damaged group, the men showed a nonsignificant trend toward better Block Design performance relative to the women, whereas there was no sex-related difference in Street performance. For the brain-damaged groups, patients with right hemisphere lesions performed significantly worse than patients with left hemisphere lesions on both the Street test and Block Design, indicating that both tasks were more sensitive to right hemisphere functioning. There was, however, a significant sex X side of lesion interaction on Block Design only, with the men showing a more asymmetrical pattern of scores. These results suggest that sex differences in functional lateralization may underlie sex differences in visuospatial ability, and that sex differences in functional lateralization may be present for only certain visuospatial processes. 相似文献