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971.
Subjects' extrapolations of a piecewise constant-velocity trajectory and a constant-acceleration trajectory were mapped out over a sequence of trials that required only a button-press response. Without any performance feedback, subjects' extrapolations of both trajectories approximated an acceleration segment followed by a constant-velocity segment. With performance feedback, subjects' extrapolations of the constant-acceleration trajectory approached optimal performance. Subsequent withdrawal of the feedback shifted the entire extrapolated trajectory. These feedback-related changes in the extrapolated trajectory can be interpreted as changes in two parameters of a cognitive representation of the movement pattern.  相似文献   
972.
Choices between risk and effort, in a format (COPE) previously shown to reflect fatigue, were obtained from subjects in noise or quiet. Both sexes were used in the experiment, half the subjects working at the Norinder arithmetic task while half rested. The COPE test took a computational form, offering choices between digit lists of differing lengths in which target sums were imbedded. The baseline choice levels were established in quiet, but half the subjects were exposed to noise during the posttest. As previously found in comparable conditions, the Norinder task showed no effect of noise. Pretest-posttest comparisons on the COPE test showed that exposure to noise, like computation work, had the predicted effect of decreasing the choice of high-probability, high-effort alternatives. The presence of noise during posttest had no overall effect on risk effort choices, although there were indications that changes of any kind in the test conditions might be a factor. The data seem difficult to explain in an arousal framework, but may be simply interpreted as showing that exposure to noise produces real fatigue.  相似文献   
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974.
The study investigated cultural bias in the 46 verbal items of the McCarthy Scales of Children's Abilities (MSCA). The verbal items of the MSCA were administered to 59 Anglo and 59 Mexican-American subjects matched for age and sex. The responses of two groups of subjects on these items were analyzed by log-linear technique using the likelihood ratio chi-square statistic. The analysis of the data revealed that the majority of the verbal items of the MSCA are free from cultural bias. Only three items of the MSCA V-scale reflected systematic cultural bias. Two of these items are from the Word Knowledge II Subtest and the third one is from the Opposite Analogies Subtest. Suggestions for the use of the MSCA with children from minority cultures are made.  相似文献   
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978.
Neonatally and adult castrated male hamsters as well as neonatally androgenized and nonandrogenized female hamsters were tested for both mounting and lordosis behaviors during treatment with either testosterone or ovarian hormones. Neonatal androgenization facilitated mounting behavior in adult animals administered either testosterone or ovarian hormones and suppressed lordosis behavior in adult ovarian-hormone-treated animals. Early androgen effects on the display of lordosis behavior during adult testosterone treatment were complex and varied with the exact timing of perinatal endogenous or exogenous androgenization. Species differences in hormone-behavior relationships and the possible role of perinatal androgenization in the development of rodents' ability to aromatize androgens were discussed.  相似文献   
979.
Preschool children's understanding of temporal relationships was examined in terms of their comprehension of sentences containing clauses linked by before and after. The relative importance of order of mention and main-subordinate relations strategies in children's interpretation of temporal order information was also evaluated.Divergent error patterns emerged on the tasks; omissions prevailed on the two tasks involving response to commands, reversals prevailed on the other. Further examination revealed that omissions reflected ambiguity in the linguistic structure of commands. Thus the effect of main-subordinate relations was confounded with directness of command. On all comprehension tasks, however, performance was superior on sentence forms in which order of mention and order of occurrence correspond.  相似文献   
980.
34 male and 34 female hospitalized psychiatric patients were divided into field-independent and field-dependent groups on the basis of rod-and-frame test performance and their MMPI scores were compared. A multiple discriminant analysis followed by a series of 2 X 2 factorial analyses of variance was used to assess the results. As in previous studies, more similarities than differences were found between the two cognitive styles. However, field-independent subjects tended to be more unconventional, aggressive, antisocial, and perhaps defensive than field-dependent subjects. Explanations of results were explored in reference to previous findings.  相似文献   
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