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921.
On the role of differential sample behaviors in matching-to-sample   总被引:6,自引:0,他引:6  
Pigeons were trained on matching-to-sample (MTS) with differential sample-response requirements that were identical with respect to two pairs of sample stimuli but were either correlated or uncorrelated with correct choice. Experiment 1A showed that birds in the uncorrelated condition were slower to reach criterion levels of accuracy than birds in the correlated condition in spite of their equivalent sample discriminations. However, correlated birds were more disrupted in their matching performances than the uncorrelated birds when subsequently switched to nondifferential sample-response requirements (Experiment 1B). Experiment 2 showed that differential sample behaviors also generated higher levels of accuracy on delayed MTS when correlated with choice, and that accuracy in this condition did not differ as a function of whether the samples were hues or lines. Sample dimension did affect memory performance, on the other hand, in the uncorrelated condition. In Experiment 3, reversing differential sample-response requirements for one pair of samples substantially reduced matching accuracy in the correlated group but had almost no effect in the uncorrelated group. These findings demonstrate that differential sample behaviors directly control pigeons' matching performances and also overshadow conditional stimulus control by the samples when these behaviors are predictive of correct choice. The facilitation in matching produced by differential sample behaviors apparently arises from the additional cue these behaviors provide, not because they enhance sample discriminability.  相似文献   
922.
D A de Rosenroll 《Adolescence》1987,22(88):791-802
This paper reviews six articles which appear to be representative of the past fifteen years during which researchers have focused on early adolescent egocentrism. Each article is described in chronological order and compared to research findings suggested by the other articles. Although the researchers have suggested some interesting associations, there is a lack of consistency among their findings. The author indicates methodological problems and questions for further research which arise from the reviewed articles.  相似文献   
923.
B M Newman  P R Newman 《Adolescence》1987,22(87):525-534
In reviewing the literature on the social impact of high school, six themes were identified: (1) students perceive strong norms for conformity to school rules, (2) the emphasis on conformity and control influences the quality of student/teacher relations which tend to be role bound and inflexible, (3) paths to social status continue to emphasize athletic competence, (4) peer group identification has an impact on social relations within the larger community as well as in the school setting, (5) powerlessness is felt as a result of the authoritarian approach to decision making, and (6) the overall high school environment does not enhance students' beliefs in the Bill of Rights. It was concluded that high school students have limited opportunities for flexible self-definition. As a result of the way they are treated by authority figures and the strong pressures toward conformity, many adolescents fail to learn the extent of their rights or effective strategies for the exercise of power.  相似文献   
924.
Youth suicide     
B P Allen 《Adolescence》1987,22(86):271-290
The literature on youth suicide (ages 15-24) is surveyed for the period 1980-1985. Emphasis is placed on general determinants of suicide, predictors in the form of psychological tests, precipitating events (immediate causes), and signs--clues that may signify impending attempts at self-destruction. Suggestions for prevention, and limitations of research on suicide are offered.  相似文献   
925.
Keeping juvenile delinquents in school: a prediction model   总被引:1,自引:0,他引:1  
The purpose of this study was to test an empirically based prediction model of school dropout on a sample of 137 juvenile delinquents, some who have dropped out and some who have remained in school. The specific factors among the many found in previous research that are salient for predicting whether delinquent youths will drop out or remain in school were determined. An important finding of this study is that it required only four factors to yield a high level of prediction: misbehavior in school, disliking school, the negative influence of peers with respect to dropping out and getting into trouble, and a marginal or weak relationship with parents. The four factors identified create a model that is directly applicable to prevention strategies and is extremely parsimonious.  相似文献   
926.
A match-to-sample task and a preference-ranking procedure were used to provide predifferentiation experiences on a color discrimination of 3-, 4-, 5-, and 6-year-old children. Chronological age was the best predictor of task success. Six-year-olds averaged twice as many correct matches as 3-year-olds. Gender and predifferentiation experience were not significant as main effects or in interactions affecting test performance. There was no difference between scores of untrained and trained children. The predifferentiation experiences had no effect. The data suggest that the years between 3 and 6 may be an important period in the development of the perceptual abilities needed to discriminate among subtle differences in one hue. Boys' and girls' abilities seem to develop at the same rate during this age span.  相似文献   
927.
This study assessed the role of family status and family relationships in the course of combat-related posttraumatic stress disorder (PTSD). The sample consisted of 382 Israeli soldiers who suffered a combat stress reaction episode during the 1982 Lebanon War. Results showed that one year after the war married soldiers had higher rates of PTSD than did unmarried soldiers. Furthermore, higher rates of PTSD were associated with low expressiveness, low cohesiveness, and high conflict in the casualties' families. Theoretical, methodological, and clinical implications are discussed.  相似文献   
928.
Chronic Illness and the Life Cycle:A Conceptual Framework   总被引:2,自引:0,他引:2  
This article provides a conceptual framework for thinking about the system created at the interface of chronic illness with the family life cycle. First, a psychosocial typology and time phases of illness schema is described as a necessary, preliminary step to create a common language that bridges the worlds of illness, individual, and family development. This schema organizes similarities and differences between diseases in a manner useful to psychosocial-developmental rather than biomedical inquiry. Then, drawing on several major life-cycle theories in the literature, key concepts (periods of transition, life-structure building and maintaining, centripetality, and centrifugality) are used in a complementary fashion to link these three lines of development. Equipped with these psychosocial languages, consideration is given to transgenerational aspects of illness, loss, and crisis, and the interwoven threads of illness, family, and individual development. Clinical vignettes are provided to highlight this conceptual framework.  相似文献   
929.
In the various models of family therapy, family systems are described as being patterned and programmed in their operations and development. The regularities and patterns found in family life are believed to be the expression of a program that determines the behavior of the family system and each of its members. Therapists holding this view will use "programming methods" in order to map family phenomena, and therapeutic work will consist of disrupting the problematic sequences in a deterministic way. However, if we take into consideration the impossibility of always linking inputs and outputs and the inability to evaluate consistently the behaviors in a system, problems associated with indeterminancy appear. Under such conditions, it may be impossible for therapists to formulate programs of family functioning. Therefore, we have operationalized a set of methodological principles that can be applied in such conditions. In this article we present the theoretical and practical implications for the field of therapy of "nonprogramming methods." A videotaped session is analyzed in order to show the application of the nonprogramming methods in clinical practice.  相似文献   
930.
KARL TOMM  M.D. 《Family process》1987,26(1):3-13
A clinical interview affords far more opportunities to act therapeutically than most therapists realize. Because so many of these opportunities remain outside the therapist's conscious awareness, it is useful to elaborate guidelines that orient his or her general activity in directions that are liable to be therapeutic. The Milan associates defined three such basic guidelines: hypothesizing, circularity, and neutrality. Hypothesizing is clear and easy to accept. The notions of circularity and neutrality have aroused considerable interest but are not as readily understood. These guidelines may be clarified and operationalized when reformulated as conceptual postures. This process is enhanced by differentiating a fourth guideline, strategizing, which entails the therapist's decision making, including decisions about how to employ these postures. This paper, the first in a series of three, explores these four interviewing guidelines. The other papers will appear in a subsequent issue. Part II will focus on reflexive questioning, a mode of inquiry oriented toward mobilizing the family's own healing capacity. Part III will provide a scheme for analyzing and choosing among four major types of questions: linear questions, circular questions, reflexive questions, and strategic questions.  相似文献   
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