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51.
Levels and correlates of parental support, peer support, partner support, and/or spiritual support among African American and Caucasian youth were examined in three contexts: adolescent pregnancy (Study 1), first year of college (Study 2), and adolescence and young adulthood (ages 15–29; Study 3). Partially consistent with a cultural specificity perspective, in different contexts different support sources were higher in level and/or more strongly related to adjustment for one ethnic group than the other. Among pregnant adolescents, levels of spiritual support were higher for African Americans than Caucasians; additionally, peer support was positively related to well-being only for African Americans whereas partner support was positively related to well-being only for Caucasians. Among college freshmen, family support was more strongly related to institutional and goal commitment for African Americans than Caucasians; conversely, peer support was more strongly related to institutional and goal commitment among Caucasians. Among 15 to 29-year-olds, levels of parental support and spiritual support were higher among African Americans than Caucasians; additionally, spiritual support was positively related to self-esteem for African Americans but not for Caucasians. Implications and limitations of the research are discussed. The third study was supported by National Institute of Mental Health Grant RO1 MH40963. We thank Monica Greene, Shea Lyda, Wendy Stevenson, and the many undergraduate students who contributed to the three research projects. We also acknowledge the very thoughtful and helpful comments of the anonymous reviewers and the editor, Edison Trickett.  相似文献   
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Recent studies have documented the increasing trend among school districts toward adopting full inclusion as the predominant model for serving students who qualify for special education services. Although these data may suggest that a paradigm shift has already taken place and that a consensus of opinion has been achieved, several organizations representing students with specific disabilities continue to support a continuum of placement options. This paper challenges a one size fits all approach to special education, and highlights the importance of considering the individual characteristics of students. The relevance of research on full inclusion, as well as methodological issues that limit generalizability of findings related to student outcomes, are discussed. The radical perspective of full inclusion is rejected in favor of an approach that emphasizes the complexities of placement decisions.  相似文献   
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The results of an earlier study (Olsho, 1984) indicated that 5- to 8-month-old infants were relatively better at discriminating among high-frequency pitches than low. In the present study, sensory and nonsensory explanations for that effect were evaluated by examining infants' performance in a task requiring similar sensory processing but differing in the demands placed on processes such as memory. Infants' ability to resolve frequency was tested using a tonal masking paradigm, the psychophysical tuning curve. Twenty-four infants were tested at probe frequencies ranging from 500 to 4000 Hz; a group of young adults served as a comparison. Masked and unmasked thresholds were estimated using the visually reinforced head turn procedure in conjunction with an adaptive psychophysical method. Although infants' tuning curves fell below those of adults (indicating poorer performance), the widths and slopes of the infants' curves were not different from the adults'. Moreover, the difference between age groups remained constant across probe frequencies. These findings imply that by 5 months of age, the infant's ability to resolve sound frequency is similar to the adult's.  相似文献   
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In a replication of two investigations reported by Looft (1971a, 1971b), 40 second- and sixth-grade male and female students were interviewed concerning their desired and expected vocational aspirations. In contrast to Looft's findings, no significant sex differences were found for either grade level in (a) the number of different (nonoverlapping) vocations nominated or (b) the number of subjects changing initial vocational role choices. When the issue of traditionality of vocational choice (i.e., vocations socially identified with the sex of the subject) was examined, it was found that half of the sixth-grade females interviewed nominated nontraditional vocations (e.g., basketball player, police officer). It was observed further that males in both the second- and sixth-grade samples overwhelmingly nominated traditional vocations. Contrary to Looft's interpretation, the findings suggest that although goals associated with the women's liberation movement (e.g., changes in sex-role expectations) are not demonstrated clearly in the vocational aspirations or expectations of young children, they may be reflected in the aspirations of adolescent females.  相似文献   
56.
While the literature suggests that males are less emotionally expressive than females, the issue has been informed by little systematic research. This article investigates the differences between sons' and daughters' perceptions of their mothers' and fathers' expressiveness of several emotions, both verbally and nonverbally. Using a sample of 1,245 students the dependent variable, perceived expressiveness of parents, was determined from responses to a 16-item Likert-type Perceived Parental Expressiveness Scale (PPES). It was hypothesized that fathers would be perceived to be less expressive than mothers. T tests were used to determine whether the mean differences are significant. The data indicate that fathers are perceived as less expressive of all emotions except physical anger. The ramifications of these findings for sex-role learning are discussed.The research reported in this paper is part of National Institute of Mental Health Grant No. 22156-01, The Inexpressive Male (Jack Balswick, Principal Investigator), University of Georgia. The authors wish to thank Dr. Charles W. Peek for his assistance in the revision of this article.  相似文献   
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Three sources of potential error in reaction time measurement may occur when raster scan CRT displays are used to present stimuli: phosphor persistence, sweep delay, or transmission delay. For most applications, only the third source of error is likely to be significant.  相似文献   
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The long-term effects of infantile malnutrition on information processing were studied in squirrel monkeys. From 2 through 8 weeks of age, four low-calorie infants were fed reduced amounts of a high protein diet, limiting their mean body weight gain to 23% of that of four well-fed controls, with all of this gain occurring during the first 2 weeks on the low-calorie diet. Thereafter, both groups received the standard diet ad libitum. At 68 weeks of age, incidental learning was tested by introducing shape cues that were redundant to the solution of a previously learned, two-choice, color discrimination. Removal of the color cues showed that the low-calorie monkeys had learned significantly less about the shape cues than had the controls. The basis for this incidental learning failure was then examined with an embedded-figures dicrimination, to measure attentional ability, and a novel stimulus substitution task, to measure curiosity. The groups did not differ in detecting embedded figures, but the low-calorie monkeys were significantly less likely than controls to select or handle novel stimuli that had been substituted for previously learned discriminative cues. It was concluded that undernutrition in infancy may induce a long-term strategy of only learning information which leads to an immediate reward, while suppressing the acquisition of information due to intrinsic curiosity.  相似文献   
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