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841.
This investigation examined the relationship between methylphenidate (MPH) and the learning and recall of paired associations by children with attention deficit disorder with hyperactivity (ADDH). Forty-five children with ADDH were randomly assigned to one of three groups (novel, partial mastery, and mastery learning) that varied in the amount of previous learning of paired associations and participated in a double-blind, placebo-control, repeated-measures-across-dose (crossover) design. Each child received four doses of MPH (5 mg, 10 mg, 15 mg, and 20 mg) and a placebo in a random, counterbalanced sequence. The results indicated that both the rate of acquisition and accuracy in learning paired associations were significantly, but differentially, affected by MPH dose and the degree of learning mastery. The implications of these results for psychopharmacological research and the monitoring of psychostimulant effects on children's learning performance in academic settings are discussed.The authors wish to acknowledge and express their sincere appreciation to the graduate and undergraduate student members of the Children's Learning Clinic.  相似文献   
842.
Depressive characteristics of physically abused children   总被引:4,自引:0,他引:4  
Physically abused and nonabused children were compared on child-completed measures of depression, hopelessness, self-esteem, and locus of control. Results indicated that, in comparison with nonabused controls, abused children evidenced more depressive symptoms, heightened externality, lower self-esteem, and greater hopelessness about the future. Group differences in depressive symptomatology were not accounted for on the basis of differences in age, sex, race, gender, IQ, or socioeconomic status. Results replicate the results of Kazdin, Moser, Colbus, and Bell (1985) derived from a sample of physically abused psychiatric inpatients and extend the generality of these findings to abused children of nonpatient status. Implications of the findings for clinical interventions, theoretical models of child depression, and future research are discussed.The authors wish to thank Alvin Hadley and the staff of Franklin County Children Services.Appreciation is also extended to Dr. Charles Wenar.  相似文献   
843.
This study investigated the most common precipitants of adolescent suicide attempts and the strategies used to cope with such problems. Adolescent suicide attempters were compared with both distressed and nondistressed nonsuicidal adolescents on problems reported and coping strategies utilized. All three groups reported four problems as occurring most frequently: school, parents, friends, or boyfriend/girlfriend. The suicide attempters and distressed controls reported problems with parents more frequently than did nondistressed controls, while this latter group reported problems at school more frequently than did suicide attempters or distressed controls. Suicide attempters used social withdrawal, problem solving, and emotional regulation more than did nondistressed controls, but not more frequently than distressed controls. Distressed controls used wishful thinking and resignation more than did suicide atempters. Results are discussed in terms of the similarities between suicide attempters and nonsuicidal distressed adolescents and the need to more closely investigate specific subgroups of suicide attempters.  相似文献   
844.
This study investigated problems commonly experienced by adolescents and the strategies they use to cope with these events. Coping strategies were examined across the subjects' omotional state and their evaluation of the problem. In general, adolescents reported four common Stressors that were similar across age groups and gender. However, males differed from females in the frequency of these problems. Further, while the Stressors were similar, the frequency with which the coping strategies were employed and the efficacy ascribed to them differed across sex and across problem type. These findings are discussed in terms of the stress and coping literature with adults and the implications for clinical assessment and treatment of adolescents.  相似文献   
845.
The validity of verbal protocols   总被引:3,自引:0,他引:3  
The reactivity of a "think aloud" verbal protocol and the veridicality of different retrospective protocols were tested over four dissimilar tasks. Generating a concurrent protocol altered accuracy in two tasks, simple addition and a choice between two gambles, and generally prolonged response times. Such reactivity partially qualifies the dominant theory of protocol generation (Ericsson & Simon, 1984). Retrospective protocols yielded substantial forgetting or fabrication in all tasks, supporting the consensus on the nonveridicality of these methods. It is concluded that protocol validity should be based on an empirical check rather than on theory-based assurances.  相似文献   
846.
Explanations of context effects in the Reicher-Wheeler task and the letter-identification task appeal to word-based processing, yet these tasks provide no explicit measure of word processing. An experiment is reported which was designed to investigate the use of transfer in the word-identification task as a measure of word-based processing in letter-identification tasks. It was found that encoding manipulations that determined whether a word-superiority effect was or was not found in a letter-identification task (e.g., Thompson & Massaro, 1973) also determined whether transfer was or was not found in a subsequent word-identification task. The results of the experiment are discussed in terms of the utility of using transfer experiments as converging evidence about the presence and/or absence of processes that cannot be directly measured in other experimental paradigms.  相似文献   
847.
848.
The expansion of mental health services during the 1960s from a single remote mental hospital to centers and clinics in mainstream communities fostered the development of community psychology in Hong Kong. Few psychologists were initially involved in the local community mental health movement, but its momentum resulted in increasing numbers of practitioner psychologists working in community-based service settings. Community psychology in Hong Kong today consists primarily of service delivery, but also includes applied research, community organization/consultation, and community education. Despite having many parallels with the American situation, key concepts underpinning the practice of community psychology in the Territory possess their own character as a reflection of nuances in the local scene. Prospects for the continued development of community psychology in Hong Kong appear favorable. Of special relevance is the field's potential contribution to a better understanding of the psychological phenomena associated with the Territory's sociopolitical transformation in 1997.  相似文献   
849.
850.
An algorithm is presented for the best least-squares fitting correlation matrix approximating a given missing value or improper correlation matrix. The proposed algorithm is based upon a solution for Mosier's oblique Procrustes rotation problem offered by ten Berge and Nevels. A necessary and sufficient condition is given for a solution to yield the unique global minimum of the least-squares function. Empirical verification of the condition indicates that the occurrence of non-optimal solutions with the proposed algorithm is very unlikely. A possible drawback of the optimal solution is that it is a singular matrix of necessity. In cases where singularity is undesirable, one may impose the additional nonsingularity constraint that the smallest eigenvalue of the solution be , where is an arbitrary small positive constant. Finally, it may be desirable to weight the squared errors of estimation differentially. A generalized solution is derived which satisfies the additional nonsingularity constraint and also allows for weighting. The generalized solution can readily be obtained from the standard unweighted singular solution by transforming the observed improper correlation matrix in a suitable way.  相似文献   
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