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891.
892.
Three pigeons pecked at letters of the alphabet and at the symbol "?" displayed on a computer-driven cathode ray screen. A 4 by 4 matrix of infrared emitting and detecting diodes and associated circuitry identified the location of a pigeon''s responses to the screen. Responses at the target letter T were probabilistically reinforced with food whenever T appeared in a string of three letters in the middle of the screen. Responses at the symbol "?" appearing below this string were probabilistically reinforced whenever T did not appear. The letter F anywhere in the three-character string either strongly predicted the occurrence of the target letter T, in two conditions, or predicted its nonoccurrence, in a third. This manipulation of the frequency with which the familiar letter F predicted T was shown to change the function relating probability of a correct peck at the symbol "?" to the number of Fs in the string. This effect may be interpreted as an instance of the phenomenon where an organism''s acquired knowledge changes what it sees.  相似文献   
893.
The present experiment used hippocampal stimulation to determine the temporal gradient of consolidation of spatial working memory. Rats were trained to perform a spatial working memory task on a radial maze with 12 arms. Each rat went to the ends of 6 arms to obtain a food reward. After 8 h, the rat chose among all the arms to find the ones not previously chosen (and consequently still having food). During some test sessions, the hippocampus was stimulated electrically either at a current level just high enough to produce an electrophysiological seizure, or at a current level below this seizure threshold. Stimulation occurred at one of five intervals (0 to 8 h) following the completion of the first six choices. During other test sessions, the hippocampus was not stimulated. After seizure stimulation, the number of retroactive errors (returning to arms chosen prior to stimulation) increased at all delay intervals; the number of proactive errors (returning to arms chosen after stimulation) increased only with the delay of 8 h. Subthreshold stimulation had no influence on either type of error. These results indicate that normal hippocampal function is required for the maintenance of spatial information in working memory, and that the time course of consolidation of this information is significantly greater than that seen in other types of memory, or consolidation may not take place at all.  相似文献   
894.
To increase understanding of the relationships between gender and causal attributions, dispositional and situational variables were examined to determine if they affected causal attributions differently if the subjects were females or males. Four dispositional variables—locus of control, neuroticism, achievement motivation, and self-esteem—and five situational variables—expectancy of success, self-reported commitment, perceived productivity, perceived task complexity, and actual performance—were examined for their moderating effects on the gender-causal attributional relationships. The dispositional variables did not moderate any causal relationships. By comparison, four situational variables—performance, commitment, productivity, and complexity—moderated at least one of the gender-attribution relationships. It was concluded that more attention should be directed to the identification of situational moderators.  相似文献   
895.
Some effects of color on naming and recognition of objects   总被引:1,自引:0,他引:1  
In this article, we investigated the role of color in the recognition and naming of everyday objects. In the first experiment we found that color pictures were named faster than black-and-white and that shape information did not facilitate color naming. Experiment 2 was carried out to determine at which stage of object processing the color facilitation occurred. We found that color had no effect on object recognition but did facilitate object naming, even when color was redundant for discrimination. This did not apply to naming abstract shapes. Experiment 3 replicated the findings of Experiment 2 using different objects and colors. The results showed that color could facilitate but not inhibit object naming and did not affect object recognition.  相似文献   
896.
This study describes the development of the Attitudes Toward Women Scale for Adolescents (AWSA), an instrument based on the short form of the Spence-Helmreich Attitudes Toward Women Scale (AWS). The AWSA has been tested in four samples of adolescents. Internal consistency estimates and test-retest stability indicated high reliability. Hypotheses formulated to test the construct validity of the scale were largely supported. AWSA permits the examination of how boys' and girls' attitudes toward women influence the life paths that adolescent girls begin to pursue.This research was supported by grants to A. Petersen from the Spencer Foundation, the National Institute of Mental health (MH 30252/38142), and the Judith Baskin Offer Fund.  相似文献   
897.
This research examined the creative writing of 180 elementary school children for evidence of sex difference and sex-role perceptions. Stories were analyzed for frequency of male and female characters, attributes, and roles. Writers were equally divided by sex and into three age groups—grades 1–2, 3–4, and 5–6. Results suggest that the total number of characters, roles, and attributes was equivalent. However, the distribution of male and female characters, roles, and attributes differed with male and female writers. Female writers included significantly more female characters and assigned more attributes and roles to these characters. Nevertheless, in the stories of both male and female writers, there was a predominance of male characters and assignment of attributes and roles to male characters. The findings support the development and implementation of a nonsexist curriculum.  相似文献   
898.
This study examined the role of gender of observer, parent, and child on judgments of the severity, appropriateness, and consequences of various forms of discipline. Young adults read stories describing a disciplinary encounter between parent and child and made required judgments. Consistent gender differences emerged. Females judged the discipline more harshly than males, rating it as more severe, more abusive, less appropriate, and more likely to result in emotional harm. Discipline of daughters was judged to be harsher than identical treatment of sons, particularly when the discipline was administered by the father. The implications of differential judgments are discussed.  相似文献   
899.
Stephen  Timothy D.  Harrison  Teresa M. 《Sex roles》1985,12(1-2):195-206
The present study was designed to investigate the relationship experience of males and females who do not conform to sex-typical orientations to intimacy. One hundred sixty-three couples' and 88 nondating singles' (total N=414) responses to the Relationship World Index—Version 2 (RWI-2) were analyzed via discriminant analysis to determine if subjects' sex could be predicted accurately upon the basis of their RWI-2 scores. One discriminant function was found which was significant by the Wilks' lambda test [x2(60)=140.57, p<.001]; the procedure correctly classified 76% of the respondents. Those who were classified correctly were considered sex-typical and the remaining 24% of the sample was considered non-sex-typical in their orientations to intimacy. Additional analyses using data from a 6-month longitudinal study located qualities which significantly distinguished sex-typical from non-sex-typical subjects and couples in which at least one member was non-sex-typical from couples in which both members were classified as sex-typical.  相似文献   
900.
The purpose of this study was to examine the attitudes of a general population toward female participation in sports and to replicate a previous study. The two areas investigated were (1) the perception of enhancement or detraction of femininity by girls' participation in athletics, and (2) whether different sports elicited different attitudes towards female participation in athletics. A town in Iowa was sampled. The results indicated that, in general, participation in sports neither detracted from nor enhanced femininity. Furthermore, most of the people wanted their daughters to play basketball, even though it neither detracted from nor enhanced femininity. The data suggest that traditional, rigid sex-role stereotypes were transcended and the opportunity set was dominant.This study was partially funded by a grant from the University of Iowa Graduate School. Appreciation is expressed to Dr. Eldon Snyder for graciously sharing his instrument and recent work.  相似文献   
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