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221.
Two treatment tactics, food and praise contingent on appropriate play and varying doses of methylphenidate (Ritalin), were evaluated for their effects on a preschool child's activity changes. In addition, other social, verbal, and academic behaviors were monitored to examine possible side effects of the two treatment tactics. Fewer free-play activity changes occurred during contingent reinforcement phases while medication had variable effects: increasing attention to tasks but, at higher doses, decreasing intelligibility of speech and responsiveness to mands. The study outlines a replicable model for comparing medication with alternative behavioral strategies to control hyperactivity and enhance skill development. 相似文献
222.
A series of four experiments is reported in which reaction times for naming line drawings were analyzed as a function of the similarity of the print superimposed on the drawings to the printed label for the drawing. This effect was studied as a function of grade level (ages 6, 8, and 11 years) and, hence, reading experience. The studies were designed to determine more precisely the characteristics of the stage of visual feature analysis of word identification and to examine response competition factors in this interference task. Results indicated that a combination of end letters and word shape was important for word identification and that response articulation was a significant distinct interference component in this task. 相似文献
223.
Preschool children in day schools were given instructions to complete certain tasks. Four tasks were given of two types and two levels of difficulty. In each condition compliance with at most one instruction (one task) was reinforced. In two similar experiments, with six children, general results were: compliance with easy tasks was maintained without reinforcement when any task compliance was reinforced; compliance for hard tasks remained high only when that specific task was reinforced. Thus, generalization of compliance with instructions varied with task difficulty. The setting and procedure for both studies were designed to reduce possible coercive features of laboratory studies of generalized performance. Results show generalized performance can occur under naturalistic conditions. The effect of effort, as a response characteristic affecting generalized performance, is discussed. 相似文献
224.
Laboratory rats were given escape training in both arms of a Y maze followed by extinction in one of four conditions: regular (no shock), punished (both arms containing a shock mid-segment), choice, or forced (one arm containing a shock mid-segment, one arm shock free). Subjects in the punished and forced conditions required more extinction trials than those in the regular extinction condition. The choice condition was intermediate and not significantly different from the others. Choice subjects avoided the shock by choosing the safe alley early and consistently during extinction, but some continued to run for many trials without further punishment. It was suggested that the number of punished trials early in extinction is related to persistence of running, and the results were discussed in relation to the Mowrer-Brown and the discrimination hypotheses. 相似文献
225.
Two hundred consecutively seen aphasics, 142 of them with infarcts, were examined by tests of fluency, comprehension, repetition, naming, and information content. The language scores were subjected to a minimum variance clustering algorithm separately for the total and for the infarct groups. The latter generated 10 clusters on a dendrogram. Attribute analysis of each cluster provided a clinically meaningful profile of language performance for these groups. The degree of correlation of most computer generated clusters with clinically recognized groups was high, and the homogeneity of some of the clusters is striking. An exception appears to be “conduction aphasia,” which is bimodally distributed. One of these clusters, with high fluency and low comprehension scores, was renamed “afferent conduction” aphasia, and the other, with lower fluency and higher comprehension, was renamed “efferent conduction” aphasia. The Principal Components Analysis was used to evaluate the discriminatory value of language characteristics, and the Nearest Neighbor Network Analysis was used to evaluate the significance of clustering. The dendrogram for all aphasics showed a less specific and less homogenous six clusters. 相似文献
226.
A Greek-born aphasic who had been able to speak four languages (Romanian, Russian, Greek, German) was tested quantitatively for verbal expression (standard interview indexes) and verbal reception (fifth part of the Token Test). The form of aphasia (qualitative aspect) was found to be identical for all four languages. Quantitatively, his performance in the four languages was different, with the languages used most during the past 20 years (Romanian and Russian) being less impaired. Nevertheless, verbal reception was equally impaired quantitatively in all four languages. Treatment with semantic-syntagmatic methods performed in Romanian had a beneficial effect on speech in the other languages as well. The authors feel that the expressive disturbance noted in aphasia reflects involvement of deep as well as of surface structures of language, but the receptive disturbance reflects involvement of the deep structures only. This may account for quantitative discrepancies in expression without discrepancy in reception among the four languages, as well as the qualitatively identical features of the disturbance in verbal expression and reception. 相似文献
227.
A theory of intelligence is couched in stimulus-response terms, bridging the gap between S-R and cognitive psychology. The chief theoretical concepts are span ability (a capacity notion), response string (sequentially cued responses), and complexity of stimulus control (task complexity). Span is equated with the ability to respond appropriately when several cues are conjunctively relevant for correct performance (complex stimulus control). So defined, span is consistently and broadly related to many aspects of intelligent behavior. 相似文献
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