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921.
Concepts and conceptual structure   总被引:16,自引:0,他引:16  
Research and theory on categorization and conceptual structure have recently undergone two major shifts. The first shift is from the assumption that concepts have defining properties (the classical view) to the idea that concept representations may be based on properties that are only characteristic or typical of category examples (the probabilistic view). Both the probabilistic view and the classical view assume that categorization is driven by similarity relations. A major problem with describing category structure in terms of similarity is that the notion of similarity is too unconstrained to give an account of conceptual coherence. The second major shift is from the idea that concepts are organized by similarity to the idea that concepts are organized around theories. In this article, the evidence and rationale associated with these shifts are described, and one means of integrating similarity-based and theory-driven categorization is outlined.  相似文献   
922.
This study investigated ways in which predictions from interference theory might explain partial or total failure in the morning recall of mental sleep experience (MSE) episodes reported after provoked night awakening. Interference could take place either between the contents of one MSE episode (intraserial interference) or between the contents of different MSE episodes (interserial interference) and would be more likely to affect morning recall where similar (i.e., interrelated) contents in MSEs are involved. If interference were mainly intraserial, in the morning there would be no change in the difficulty of retrieving interrelated contents, whereas, if it were mainly interserial, there would be increased difficulty in the retrieval of such contents. All the possible pairs of reports obtained by awakening 8 subjects four times in REM sleep during each of four experimental nights spaced at weekly intervals were scored for interrelated contents, using Clark's (1970) system of analysis of paired units, which operates by matching linguistic features. Results showed that interrelations in morning report pairs are as frequent as in night report pairs, maintaining the same linguistic characteristics and with little transfer of contents from one MSE to another. Overall these findings are compatible with the hypothesis that interference is primarily intraserial rather than interserial. It is consequently suggested that morning recall failure may be due to temporary blocking of retrieval.  相似文献   
923.
924.
J Reis  A Seidl 《Adolescence》1989,24(95):639-645
The emergence of AIDS as an untreatable, lethal disease, responding to educational prevention strategies in high-risk populations, has brought the issues of sex education in the public schools to the forefront. However, administrators, teachers, and parents perceive different barriers to sex education implementation. This study, undertaken in a northeastern, multigenerational, ethnic city, characterized by adolescent pregnancy rates a third higher than the state overall, polled 42 junior and senior high school administrators regarding educational priorities, perceived barriers to expansion of sex education, and preferred methods of introducing sex education. Administrators perceive parents as a major barrier to the introduction of more formalized sex education in their schools. Paradoxically, these same administrators felt that parents were generally uncomfortable in talking to their children about human sexuality. Recommendations are offered from existing models of health education for resolution of administrators' conflicting views on parental roles.  相似文献   
925.
A McCombs  R Forehand 《Adolescence》1989,24(96):871-880
Most research on the effects of divorce on children has focused on delineation of specific areas of child maladjustment. A more optimistic approach seeks to identify variables that may mediate negative effects of a stressor, such as parental divorce. The goal of this study was to examine the relationship between one area of child adjustment, school achievement, and family factors which may mediate the negative influence of divorce. The subjects were 71 early adolescents and their recently divorced mothers. The adolescents were divided into low, medium, and high grade achievement groups. Analyses of variance and subsequent Newman-Keuls tests revealed that adolescents with high grade point averages had mothers with a lower level of depression, a higher educational level, less conflict with their ex-spouse, and less intense levels of conflict between mother and adolescent than those in the low grade point average group. A discriminant analysis resulted in a two-variable equation which accounted for 33% of the variance between low and high grade achievers. The two variables were mother's report of conflict between her and her ex-spouse in front of the adolescent and the adolescent's report of the intensity of arguments between him/herself and mother. These results indicated that school performance following divorce is not uniform for all adolescents and that family factors may mediate scholastic achievement problems.  相似文献   
926.
The Social Phobia and Anxiety Inventory (SPAI) is an empirically derived self-report inventory developed as a specific measure of social phobia. The current investigation included two studies. The first examined the correlation of the SPAI with daily social behavior of a clinic sample of social phobics. The results indicated that the SPAI provides a reasonable indication of the distress experienced during daily social encounters in three dimensions: behavior, cognitions, and overall distress. The second study examined the validity of the SPAI with reference to the somatic response and avoidance behavior of social phobics. The results indicated that the somatic items of the SPAI are related to the somatic response of social phobics and that performance on the SPAI is associated with avoidance behavior in an anxiety-producing task.  相似文献   
927.
Cognitive bias, i.e. overestimates of subjective probability and cost of catastrophic events, and irrational belief were explored as predictors of avoidance. Three groups-anxiety disordered clients, a mixed group of clinic outpatients, and normals--were administered several self-report inventories. Multiple regression analyses were used to investigate a modified version of the Agoraphobic Cognitions Questionnaire, the Belief Scale, and the Body Sensations Questionnaire as predictors of avoidance, as measured by the Mobility Inventory. It was hypothesized that frequency x probability x cost of catastrophic cognitions (and the occurrence of the events they represent) would be a better predictor of avoidance than frequency alone. It was also hypothesized that irrational thinking would be a significant predictor of avoidance. The results generally supported the hypotheses, with subjective probability emerging as a particularly potent predictor of avoidance. Theoretical and clinical implications are discussed.  相似文献   
928.
Recent reports in the literature suggest that anxious individuals show an attentional bias to mood-congruent information. Various investigators have hypothesized that such anxiety-based coding biases contribute to the maintenance of mood disorders. The present study sought to determine if attentional biases in anxious subjects extends to the perception of neutral, as opposed to affect-laden, stimuli. A procedure used to determine the locus of attention to foveal and peripheral visual events was used in combination with two inter-stimulus intervals, fixed and variable, to examine anxious and non-anxious subjects' attentional biases. Mood states were established by a well-validated musical induction procedure. The results revealed an attentional bias to foveal visual events in non-anxious subjects and an attenuated or reversed (peripheral) bias in anxious subjects. The clinical implications of these findings are discussed.  相似文献   
929.
Restrained eaters are rapidly habituating sensation seekers   总被引:1,自引:0,他引:1  
Several authors have pointed to similarities between eating disorders and addictive behaviors. In earlier studies, addicts were found to score high on the Sensation Seeking Scale (SSS) and to habituate rapidly to neutral stimuli. In this study, we found experimental support for an addiction model of eating disorders: restrained eaters also scored significantly higher on the Sensation Seeking Scale and also habituated significantly quicker to a series of neutral stimuli than unrestrained eaters. No clear evidence was found for the hypothesis that restrained eaters score lower on measurements of anxiety. It is hypothesized that rapid habituation promotes sensation seeking, which may be manifested in excessive consumption of either drugs or food. Restraint may be a strategy to prevent negative consequences of sensation seeking and excessive consumption. The model is related to earlier experimental findings.  相似文献   
930.
The purpose of this study was to compare our structured research-based version of marital therapy from a social learning perspective with a clinically flexible version of the same treatment where treatment plans were individually-based and there was no specific number of treatment sessions. Thirty distressed married couples were randomly assigned to one of these two treatments. Assessment of outcome was based on global marital satisfaction, spouse reports of functioning in specific areas, and direct observational measures of communication. At posttest there were no differences in efficacy between structured and flexible treatments, although both treatments led to significant improvements. At a 6-month follow-up couples treated with the structured format were more likely to have deteriorated and flexibly treated couples were more likely to have maintained their treatment gains.  相似文献   
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