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181.
A handedness questionnaire was administered to 446 stutterers and a control group. No significant male/female or stutterer/control effects were found, although both males and stutterers tended to be less right handed. The slight sex effect in handedness is consistent with previously reported studies and with cerebral structural and functional asymmetries.  相似文献   
182.
Token-mediated access to play and snacks was made contingent on completion of academic tasks in the Baseline Experiment. This contingency produced stable completion rates that were subsequently doubled, and then tripled, for four deviant children in a special preschool. A reversal design demonstrated that the contingency was functional in maintaining the children's rates of task completion. The Guidance Experiment examined the role of a social event, teacher guidance, in the acquisition of task-completion skills, in a multiple-baseline-across-tasks design (with reversals). The analysis demonstrated that teacher guidance was an important supplement to the token-mediated contingency in establishing significant increases in task completions for a second group of three deviant children in the special class. The importance of teacher guidance was related to the difficulty level of the children's tasks.  相似文献   
183.
Laboratory dogs were trained to press a response panel to postpone shocks during daily one-hour avoidance conditioning periods. Each dog was also confined in the experimental environment for 5 hours prior to the avoidance periods. Blood pressure and heart rate were monitored continuously during these experiments from chronically indwelling arterial catheters. Extended training resulted in the emergence of a cardiovascular response pattern during the pre-avoidance interval characterized by gradual increases in blood pressure together with decreases in heart rate. Elevations in both blood pressure and heart rate were sustained during the avoidance periods. During sessions in which alpha adrenergic activity was suppressed by phenoxybenzamine, absolute levels of blond pressure were found to be lower than during control (non-drug) sessions, but a progressive rise in blood pressure continued to be observed during pre-avoidance. These results suggest that sustained cardiovascular responses during avoidance periods are associated with activation of the sympathetic nervous system, but that the gradual rise in blood pressure during pre-avoidance is due to other factors.  相似文献   
184.
The concept of standards lacks clarity because it is applied both to concrete specifications and to the assessment of quality. Confusion is reduced by introducing the notion of interchange expectancy. distinguishing transfer, coupling, and market success as components. Transfer expectancy depends upon the products to be transported or exchanged, but when there is a need to estimate transfer expectancy, a combination of technical standards and performance standards must be applied. Though performance standards are intended to produce quality, the quality of the instrumentation to measure performance standards is often neglected. The development of high-quality performance standards first requires the delineation of the relevant dimensions of performance quality. The process of giving precision to performance standards may lead to the emergence of more acceptable technical standards. To illustrate some of these points, data is presented from the CONDUIT system for quality evaluation of computer-based curriculum materials. The performance quality of these products includes the dimension of transfer expectancy, as well as educational and scientific merit. Increased specification and impact of technical standards may provide greater incentives to authors and hence lead to the invention of products which have higher educational and scientific quality.  相似文献   
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