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921.
The peak amplitude of EMG activity was measured from the orbicularis oris superior (OOS), orbicularis oris inferior (OOI) and masseter muscles for 3 normal 4-yr.-old children and compared to past data gathered on a group of articulatory disordered children, normal children, and adults. The 4-yr.-olds evidenced greater average peak EMG activity than the other groups, suggesting that speech-sound production becomes more efficient with maturation. Also, levels of variability obtained for the younger children were considerably smaller than for the normal speakers across the three muscles, showing that motor equivalence changes with age whereby the flexibility in the control of articulators increases. The coefficient of variation for the OOI muscle for the disordered children, however, was similar to that for the 4-yr.-olds, while the corresponding data for the other two muscles paralleled those for normal ones. These findings were interpreted as reflecting a delay in the development of speech-motor equivalence that affects certain muscles while sparing others. 相似文献
922.
This experiment concerned the contribution of polydipsia on the temporal discrimination of rats during a fixed-interval 60-sec. schedule. In this study, the timing accuracy of 12 rats which had access to water during training was compared to that of 12 rats which had no water during training. The rats were trained for 25 sessions on an FI 60-sec. schedule. In early sessions before polydipsia was fully developed, no differences existed between the timing accuracy of the water group and no-water group. As the amount of water drunk by the water group increased as the number of sessions increased, a parallel increase was noted in the timing accuracy of the water group. In the final sessions, a significant difference was found between the timing accuracy of rats in the water group and that of those in the no-water group. It was concluded that polydipsia facilitated the development of the temporal discrimination which is characteristic of a fixed-interval 60-sec. schedule. 相似文献
923.
Motoric change subsequent to therapeutic intervention in infants and young children who have cerebral palsy: annotated listing of group studies 总被引:1,自引:0,他引:1
This annotated listing is of group reports pertaining to therapeutic strategies utilized with infants and young children who have cerebral palsy. The studies are organized by type of design used. 相似文献
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T Krause W P Pankau A Wagner J L?ssner 《Psychiatrie, Neurologie, und medizinische Psychologie》1984,36(9):545-550
By 48 patients with Wilson's disease the brainstem acoustic evoked potentials were stated. There were 35 pathological findings (73%), 13 were normal (27%). The waves, determined by the middle and upper brainstem (Pons and Mesencephalon) showed most of all pathological changes. Those patients with forms of Wilson's disease called Pseudoskelerose and Pseudoparkinson showed the most pathological findings. But one could watch these findings by about 30% of patients in preclinical stage. This method can possibly be used for early detection of disorders of brainstem functions and in the same way it can be used for control of treatment by patients in preclinical stage. 相似文献
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This paper proposes test statistics based on the likelihood ratio principle for testing equality of proportions in correlated data with additional incomplete samples. Powers of these tests are compared through Monte Carlo simulation with those of tests proposed recently by Ekbohm (based on an unbiased estimator) and Campbell (based on a Pearson-Chi-squared type statistic). Even though tests based on the maximum likelihood principle are theoretically expected to be superior to others, at least asymptotically, results from our simulations show that the gain in power could only be slight. 相似文献