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931.
The etiology of the observed relationship between general cognitive ability and reading performance was investigated by analyzing data from samples of twin pairs tested in the Colorado Learning Disabilities Research Center. Bivariate phenotypic and genetic structural equation models were fitted to data from 486 twin pairs selected for reading deficits (276 identical and 210 same-sex fraternal) and 314 control pairs (195 identical and 119 same-sex fraternal). Subtests of the Peabody Individual Achievement test (Reading Recognition, Reading Comprehension, and Spelling) were used as measures of reading performance, and verbal and performance IQ scores from the Wechsler Intelligence Scale for Children-Revised (WISC-R) or Wechsler Adult Intelligence Scale-Revised (WAIS-R) were used as indices of general cognitive ability. The results of these confirmatory factor analyses indicate that shared environmental influences do not contribute significantly to covariation between general cognitive ability and reading performance. In contrast, genetic influences contribute substantially to the relationship between the two latent factors. Moreover, the genetic and phenotypic variances of reading performance in the proband group are larger than those in controls, whereas both the genetic and phenotypic correlations between reading performance and general cognitive ability are lower in probands. These results are consistent with recent reports that reading disability may be caused by one or more genes with major effects. 相似文献
932.
A small proportion of children and adolescents experience a debilitating level of social anxiety, known as social phobia. Initially, we consider the phenomenology and aetiology of social phobia in children and adolescents. A number of age-sensitive assessment instruments or tools are briefly considered: a diagnostic interview, selj-report instruments, behavioural observations, cognitive assessment, self-monitoring and psychophysiological recording. We explore cognitive-behavioural strategies that have been found to be useful in the management of social phobia. Although there is much research support for the efficacy of cognitive-behavioural strategies for adults with social phobia, it is emphasized that controlled evaluations have yet to be undertaken with socially phobic youngsters. 相似文献
933.
934.
Jörg R. J. Schirra 《Kognitionswissenschaft》1997,6(4):177-195
How can we explain that an assertion on something perceived can be understood in the same manner by somebody who cannot perceive that scene? This problem bases the interest in computational linguistics in how listener modeling could possibly be harmonized with reference semantics. Mental images substituting real perception appear as a way out. The architecture of the listener model has to be adapted to the creation and use of such pictorial data structures. Furthermore, the relation between the latter and a verbal (i. e., propositional) representation must be understood. The resulting architecture of a listener model with reference semantics can be employed to solve communicational problems from three general classes in a better way, as is demonstrated by an example implementation. 相似文献
935.
The globalization of the world economy, the widespread expansion of corporations into overseas markets and the increased use of expatriate and repatriate job assignments have all fundamentally changed the context in which organizational socialization now takes place. This article examines the distinctive socialization issues made salient by this organizational context change. The paper reviews existing theoretical and empirical research, provides hypotheses to guide future socialization research in this area and discusses the implications of an international context for the management of organizational socialization programmes. 相似文献
936.
Although societal need for behavioral science research is enormous, current research practices seem to be inefficient vehicles for producing knowledge that guides practical action. Many of our most popular theories provide little direct guidance for application. They focus on the development of models of the relationships among organismic events such as attitudes, self-efficacy expectations, and behavior, but pay little or no attention to the contextual influences on behavior. Such research is in keeping with a long-standing mechanistic tradition in psychology. We propose a version of contextualism as an alternative paradigm for the behavioral sciences. According to this paradigm, theories and research are evaluated in terms of their contribution to the prediction and influence of behavior. Basic research organized to pursue this goal has a direct bearing on how behavioral phenomena can be changed for practical purposes. Conversely, applied research contributes to basic understanding of the determinants of psychological phenomena. 相似文献
937.
938.
Wayne W. Fisher Cathleen C. Piazza Lynn G. Bowman Gregory P. Hanley John D. Adelinis 《Journal of applied behavior analysis》1997,30(1):105-120
Mechanical restraints are commonly used to reduce the risks associated with severe self-injurious behavior (SIB), but may result in movement restriction and adverse side effects (e.g., bone demineralization). Restraint fading may provide a method for decreasing SIB while increasing movement and reducing these side effects. In the current investigation, rigid arm sleeves and restraint fading (gradually reducing the rigidity of the sleeves) were used with 3 clients who engaged in hand-to-head SIB. Restraints and fading reduced the hand-to-head SIB of all clients. However, for 1 client, the addition of a water mist procedure further reduced SIB to near-zero levels. For a 2nd client, another form of SIB developed that was not prevented by the rigid sleeves. For a 3rd client, a topography of SIB that was not physically prevented by the rigid sleeves was also reduced when restraints and fading were introduced. 相似文献
939.
The self-stimulating rat performs foraging tasks mediated by simple computations that use interreward intervals and subjective reward magnitudes to determine stay durations. This is a simplified preparation in which to study the neurobiology of the elementary computational operations that make cognition possible, because the neural signal specifying the value of a computationally relevant variable is produced by direct electrical stimulation of a neural pathway. Newly developed measurement methods yield functions relating the subjective reward magnitude to the parameters of the neural signal. These measurements also show that the decision process that governs foraging behavior divides the subjective reward magnitude by the most recent interreward interval to determine the preferability of an option (a foraging patch). The decision process sets the parameters that determine stay durations (durations of visits to foraging patches) so that the ratios of the stay durations match the ratios of the preferabilities. 相似文献
940.