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Cultural expectations and sex-role standards about reading in Canada, Denmark, England, Finland, Israel, Japan, and U.S.A. were investigated. A picture test showing various activities and objects including reading and books was administered in each country to six sub-samples that approximated to the levels: students in grades I, IV, VIII, and XII, college students, and adults. Subjects had to ascribe the activity or object as being appropriate for either a boy or a girl. The results were consistent with the hypothesis that cultural expectations and sex-role standards about reading are congruent within one country but that they differ between countries. In particular, boys in Canada and the U.S.A. rapidly learn to perceive reading as a feminine activity, whereas Danish and Japanese males at all ages consistently view reading as acceptable masculine behaviour.  相似文献   
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Two experiments are reported comparing performance in dominant and submissive rats as determined by a food-competition procedure. Ss in Experiment I were either trained to criterion or overtrained before being reversed on a visual discrimination task. Although the two groups did not differ significantly in learning the initial task, the dominant Ss were significantly slower on reversal than the submissives. Experiment II, which utilized a tandem runway, showed that when the reinforcer which maintained the running response was not available in the first goalbox, submissive rats responded with a greater increase in running speed in the second runway than dominant rats. These findings were discussed as reflecting motivational differences between dominant and submissive rats.  相似文献   
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Twenty domestic Muscovy ducks were trained to traverse a runway for food reward. Subjects were then randomly assigned to treatments. In one treatment, subjects received six nonrewarded trials followed by six rewarded trials every day for 12 days; and, in the other treatment, subjects received six rewarded trials followed by six nonrewarded trials every day for 12 days. These successive acquisition and extinction (SAE) treatments were selected because different extinction rates on the nonrewarded trials are expected on the bases of previous research performed with rats. Analyses of variance revealed the former treatment yielded significantly greater resistance to extinction than did the latter treatment. It was concluded that ducklings performed similarly to rats in the above SAE situation.  相似文献   
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After acquisition avoidance training, rats were assigned on the basis of matched run speed to the following groups: (1) maintenance of avoidance training, (2) extinction procedures with the addition of a brief shock in the goalbox, and (3) regular extinction procedures. Each group was further divided into two minor groups which experienced either change or no change in goalbox color. The results indicated : (1) that self-punitive responding was increased by goal shock, (2) that self-punitive responding was reduced by goalbox color change, and (3) that generalization of goal shock to the startbox and runway areas is a factor in self-punitive responding.  相似文献   
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