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921.
A group of 16 children from a normal community population was compared with two groups of 16 children referred for clinical evaluation of hyperactivity. These three groups were matched on age, sex, and race. One of the clinic groups was matched with the community sample on IQ and social class as well, while the children in the other clinic group were mentally retarded and of somewhat lower social class. All children were observed in a standardized playroom for two 15-minute sessions, one under free play instructions and the other under instructions restricting activity and toy-changing behavior. The two groups of children referred for evaluation of hyperactivity had significantly higher playroom activity scores than controls under both instructional conditions and significantly higher toy-change scores under restrictive instructions. Parental ratings of activity were also significantly higher in both clinic groups than in the community group. The mentally retarded clinic sample did not differ from the other clinic sample on any of the measures of activity or toy switching.A preliminary version of this article was presented at the meeting of the American Psychological Association, Chicago, Illinois, August 30, 1975, as part of a Symposium on Hyperactive Children: Assessment, Treatment, and Outcome. This research was supported by U. S. Public Health Service, Maternal and Child Health Project No. 916 and by Grants HD-03110 and ES-01104.  相似文献   
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Recognition memory for pictures was tested using matrices of 0s and 1s as stimuli in two experiments. In the first experiment dimensionality of matrices was varied (5 X 5 and 10 X 10 matrices). The results showed better recognition memory for 10 X 10 matrices. The second experiment investigated the importance of certain areas, such as center or surround, using 10 X 10 matrices only. The results suggested that neither center nor surround is given unusual weight.  相似文献   
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The purpose of this paper is to present a new electromagnetic device which uses alternating magnetic fields for tracking movements of multiple points inside and outside the vocal tract. It is biologically safe, noninvasive, it does not interfere with speech movements, allows for multiple recording in the same subject, and for easy collection of large amounts of data. It is especially suitable for evaluation of patients with speech motor impairments.  相似文献   
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The claim (Jensen, 1975) that blacks are slower than whites in choice (but not simple) reaction time is examined. It is false. The claim (Jensen, 1985) that Muhammad Ali was shown to have a “very average” reaction time is examined. It is false. The claim (Vernon & Jensen, 1984) that an unpublished technical report showed blacks to be inferior to whites on a relatively content-free mental processing task is examined. It is false. Suggestions are made concerning relevant questions that might be addressed by students of race differences in intelligence.  相似文献   
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