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921.
A study is reported in which it is shown that observers can use at least three types of acoustic variables that indicate reliably when a moving sound source is passing: interaural temporal differences, the Doppler effect, and amplitude change. Each of these variables was presented in isolation and each was successful in indicating when a (stimulated) moving sound source passed an observer. These three variables were put into competition (with each indicating that closest passage occurred at a different time) in an effort to determine their relative importance. It was found that amplitude change dominated interaural temporal differences which, in turn, dominated the Doppler effect stimulus variable. The results are discussed in terms of two interpretations. First, it is possible that subjects based their judgements on the potential discriminability of each stimulus variable. However, because the stimuli used involved easily discriminable changes, subjects may instead have based their judgements on the independence of a stimulus variable from different environmental situation conditions. The dominance ordering obtained supports the second interpretation.  相似文献   
922.
After inducing hostility toward a confederate by threatening subjects' self-esteem, subjects were then given the opportunity either to deliver shocks (Experiment 1) or to withhold rewards (Experiment 2) from their confederate. Physiological measures were taken prior to the hostility induction, shortly after the induction and, finally, after the opportunity to aggress. Measures of individual differences relating to aggressive behavior were also considered. While the experimental manipulation was the best predictor in the ‘withholding rewards’ condition, measures of dissipation-rumination tendencies and emotional vulnerability were the best predictors in the ‘shock administration’ condition. In both conditions, systolic blood pressure seemed to reflect differences in arousal as a function of the hostility induction procedure, while subjects in the withhold rewards procedure also showed a decrease in systolic pressure after having an opportunity to aggress toward the confederate. It was concluded that not only is the withholding of rewards a more ethically acceptable procedure than shock administration, but it is also more likely to reflect experimental rather than individual difference affects.  相似文献   
923.
The term pioneer is used for girls aspiring to male-dominated careers. This longitudinal study assesses the career choices of 68 middle-class girls during childhood (8–13 years, Phase I) and again during adolescence (13–18 years, Phase II), and investigates the relation between pioneering career choice and personal and family characteristics. Subjects were originally selected for exposure vs nonexposure to exogenous hormones during pregnancy. In childhood, pioneers were somewhat older, were more often persistent tomboys, had higher IQs, and had parents with higher educational attainment. In adolescence, paternal education was the only variable that showed the same relation to career choice. Adolescent girls who had wanted to get married at the time of the childhood assessment were now less likely to choose pioneering careers. Adolescent pioneers also had higher educational aspirations than nonpioneers and less likely anticipated being married within ten years than nonpioneers. A number of statistically borderline relationships were also observed: pioneers had somewhat fewer older brothers than nonpioneers, less often came from homes in which traditional femininity was stressed, and more frequently had mothers who had worked outside the home throughout their daughters' school years than mothers of nonpioneers. Prenatal exposure to exogenous sex hormones was not related to career choice during either childhood or adolescence.  相似文献   
924.
925.
3-6岁幼儿在分类实验中概括能力的发展   总被引:5,自引:0,他引:5  
本研究通过设计不同性质的分类实验,探讨3-6岁幼儿抽象概括能力的发展。我们根据年龄将幼儿分为四个组,每组80人,共320人。通过实验获得以下几点。①幼儿在各种不同性质的分类实验中可表现为四级不同的水平,如从根据表面的个别特征进行分类发展到根据内部的本质特征进行分类,从一维角度的分类发展到从两维角度来分类等。⑦达到各个水平的年龄不是截然划分的,而是互相交织的,随着年龄的增加,低级水平的人数不断减少,高级水平的人数不断增加。所以年龄阶段之间既有质的变化,又有量的变化。③对于不同性质的分类材料,各年龄所达到的概括水平也不同,分类材料的难度越大,概括水平越低。④儿童概括水平的高低受教育条件的影响。  相似文献   
926.
Sixteen student volunteers were administered a placebo and 50 mg. of chlorpromazine in tablet form, on separate occasions, two hours before testing. The three tests measured dichotic listening performance, lateral eye movements while answering questions about spatial location and verbal meaning, and lateralized facial expression while relating pleasant and unpleasant life incidents. Results showed that chlorpromazine increased the number of trials showing an ear advantage in dichotic listening. Chlorpromazine reduced lateral and increased vertical eye movements in response to the questions about spatial location and verbal meaning. Under the placebo both negative and positive emotions were expressed more in the left face. Although chlorpromazine did not affect this lateralization of negative emotions, the expression of positive emotions occurred equally often on the two sides of the face under chlorpromazine. Results may be related to an effect of chlorpromazine on the asymmetrical dopamine pathways of the brain. It is suggested that the findings may be related to a left hemisphere deficit in schizophrenia.  相似文献   
927.
Normative data are presented for the probability of successfully completing 192 single-solution word fragments. Normative data on the familiarity of college students with the solution words are also given, along with estimates of word frequency from existing norms. Regression analyses were performed in order to predict fragment completion difficulty from familiarity, frequency, and several structural characteristics of the fragments. Familiarity, whether or not first and/or last letters appeared in the fragment, and the ratio of letters to missing letters in the fragment were included in the regression equation as significant predictors of difficulty for this fragment set.  相似文献   
928.
The Scheduled Measurement System (SMS) is a collection of related programs for administering performance and rating tasks to human subjects. It was designed to provide a common task scheduling and data management environment for a diversity of measures. SMS has greatly reduced the effort required to analyze and archive data after experiments, but it has been less successful in reducing some of the effort required to implement experiments. While programming is not difficult, documentation and user training remain the most primitive parts of the system.  相似文献   
929.
The prevalence of DSM-III conduct and adjustment disorders in two adolescent psychiatric facilities, both located near large U.S. cities, was investigated. Overall, 31.6% of the adolescent inpatients were conduct disordered while 12.5% were adjustment disordered. The conduct disorders were primarily "aggressive" subtypes suggesting that this characteristic may influence hospitalization and diagnostic decisions. Such data on prevalence assists future treatment planning, allowing anticipation of case loads.  相似文献   
930.
M L Clark 《Adolescence》1986,21(81):205-213
The differences in the personality and social backgrounds of science and non-science majors were assessed for 91 black and 109 white natural, social, and nonscience college majors. Subjects were administered the 16PF, Bem Sex-Role Inventory, and the Attitude Toward Women Scale, and data were collected on birth order, number of siblings, and social class level. Natural science majors were of a higher social class, had higher intelligence test scores, were more reserved, sober, practical, and male sex-role oriented than the social and non-science majors. Blacks and females resembled their white or male counterparts when categorized by college major.  相似文献   
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