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61.
Fragile X syndrome is primarily due to a CGG repeat expansion found in the FMR1 X-linked gene. In a previous study, we conducted focus groups with women to assess their attitudes towards fragile X carrier screening. In this follow-up study, we conducted in-depth interviews of general population reproductive-age women who were identified as carriers. We explored their attitudes toward testing for carrier status of the fragile X mutation. These women underwent screening primarily to participate in a research project rather than in search of a diagnosis for specific symptoms. As such, these women were wholly unprepared for positive carrier results. Their responses about their results and carrier screening, in many cases, were being worked out over the course of the interview itself. The most salient finding of this work is the apparent lack of relevance of carrier status to these women. Many expressed that although the information could be relevant in the future, it is not relevant at this stage of their lives in terms of family planning (either with respect to having unaffected offspring or to premature ovarian failure) and personal relationships. Although issues of abortion seemed prominent in the focus groups, we found that carrier status did not have an apparent effect on women’s attitudes about termination. We hypothesize this may be related to the fact that women had not processed their new carrier status and had not related it to previously-formed personal opinions. The findings of this work have significant implications for genetic counseling and population screening. Genetic counselors should be mindful that general population women may not recognize the immediate importance of their carrier status even when literature is provided and discussed prior to providing a sample. As part of comprehensive genetic counseling, counselors should identify the reproductive life stage of the woman receiving the new information and help her identify when this information would be more meaningful in her life. Counselors can assist in setting up a personalized road map with specific types of services that will be more applicable to the woman as her carrier status becomes more relevant.  相似文献   
62.
In English, new information typically appears late in the sentence, as does primary accent. Because of this tendency, perceivers might expect the final constituent or constituents of a sentence to contain informational focus. This expectation should in turn affect how they comprehend focus-sensitive constructions such as ellipsis sentences. Results from four experiments on sluicing sentences (e.g., The mobster implicated the thug, but we can't find out who else) suggest that perceivers do prefer to place focus late in the sentence, though that preference can be mitigated by prosodic information (pitch accents, Experiment 2) or syntactic information (clefted sentences, Experiment 3) indicating that focus is located elsewhere. Furthermore, it is not necessarily the direct object, but the informationally focused constituent that is the preferred antecedent (Experiment 4). Expectations regarding the information structure of a sentence, which are only partly cancellable by means of overt focus markers, may explain persistent biases in ellipsis resolution.  相似文献   
63.
Placing a prosodic boundary before a phrase may influence its syntactic analysis. However, the boundary’s effect depends on the presence, size, and position of other, earlier, prosodic boundaries. In three experiments, we extend previous results about the effect of the position of the early boundary. In sentences in which a final phrase may modify either a local verb or an earlier verb, a boundary immediately after the first verb leads to more first-verb attachments than when the earlier boundary appears in another position between the two verbs (Experiments 1 and 2). This effect cannot be attributed to weaker effects of more distant boundaries (Experiment 2), but is likely due to the first verb being more prominent when a boundary immediately follows it, since similar effects are observed when the verb is accented (Experiment 3). The results support the informative boundary hypothesis and show that the impact of earlier, nonlocal boundaries is not fully uniform.  相似文献   
64.
Using functional magnetic resonance imaging (fMRI) and n-back tasks we investigated whether, in 11-13-year-old children, spatial (location) and nonspatial (color) information is differentially processed during visual attention (0-back) and working memory (WM) (2-back) tasks and whether such cognitive task performance, compared to a resting state, results in regional deactivation. The location 0-back task, compared to the color 0-back task, activated segregated areas in the frontal, parietal and occipital cortices whereas no differentially activated voxels were obtained when location and color 2-back tasks were directly contrasted. Several midline cortical areas were less active during 0- and 2-back task performance than resting state. The task-induced deactivation increased with task difficulty as demonstrated by larger deactivation during 2-back than 0-back tasks. The results suggest that, in 11-13-year-old children, the visual attentional network is differently recruited by spatial and nonspatial information processing, but the functional organization of cortical activation in WM in this age group is not based on the type of information processed. Furthermore, 11-13-year-old children exhibited a similar pattern of cortical deactivation that has been reported in adults during cognitive task performance compared to a resting state.  相似文献   
65.
ABSTRACT— There are signs that the debate over racial and gender differences in intelligence is about to begin again. In this article we will be concerned primarily with racial differences but will make remarks about gender differences where applicable. Previously there have been bitter arguments over whether or not races exist, over whether it is either important or proper to study racial and gender differences in intelligence, and over the conclusions that have been drawn about environmental and genetic causes as determinants of these differences. We argue that races do, indeed, exist and that studying differences in cognitive competence between groups is a reasonable thing to do. We also point out that past research on both racial and gender differences in intelligence has been marked by methodological errors and overgeneralizations by researchers on all sides of the issue. We propose ten principles of design, analysis, and reporting that ought to be considered carefully when doing or evaluating research in this area.  相似文献   
66.
Jones  Diane Carlson 《Sex roles》2001,45(9-10):645-664
Relations among body image satisfaction and social comparisons to either same-sex peers or media models were examined in 2 studies of adolescent boys and girls. In the first study, 9th and 10th graders described their conceptions of attractiveness for same- and opposite-sex adolescents. These attractiveness attributes were then used in Study 2 in which 7th- and 10th-grade boys and girls reported on social comparisons to models/celebrities and same-sex peers. Body dissatisfaction was also assessed. The results confirmed that both same-sex peers and models/celebrities were the targets of social comparisons for physical attributes, but comparisons on personal and social attributes were more likely directed toward same-sex peers. For boys and girls, weight comparisons to both peer and model targets were primary correlates of body dissatisfaction. In addition, shape comparisons reported by the girls and facial comparisons endorsed by the boys also related to body dissatisfaction. Gender differences in social comparison indicated that girls reported more social comparisons across targets and attributes. Results are discussed in terms of the role of social comparison and peer context for body image during adolescence.  相似文献   
67.
68.
The cognitive functioning of children identified as attention deficit disorder with hyperactivity (ADD/H) was compared to that of children identified as attention deficit disorder without hyperactivity (ADD/WO). Based on information on symptoms supplied by teachers, 20 ADD/H and 15 ADD/ WO children were selected according to DSM-III criteria from a large elementaryschool learning disabilities and behavior disorders population. For comparison purposes, 16 normal children from regular classrooms were also selected. Children from all three groups were evaluated with a battery of cognitive tests. Intelligence test scores differentiated the two ADD groups, with the ADD/H children obtaining significantly lower Full Scale IQ scores than both ADD/WO and control children. In addition, ADD/H children obtained significantly lower Verbal IQ scores than ADD/WO children. Both ADD groups performed more poorly than controls on Spelling and Reading Achievement, and the ADD/WO group performed more poorly on Math Achievement. The two ADD groups took longer to complete six Stroop and rapid naming tasks than the control groups but did not differ among themselves. The ADD/WO group made more errors on a visual matching task than the controls, but neither ADD group differed from controls on the accuracy of the Stroop tasks, rapid naming tasks, measures of receptive and expressive language, visual-motor integration, or sustained visual attention. The differences between the two ADD groups were fewer than expected on the basis of previous research and are more global than specific.The assistance of John Junginger, Jason Walker, and Cynthia Jones at various stages of the project is gratefully acknowledged. Particular thanks are extended to the teachers and staff of Clarke County schools.  相似文献   
69.
The study population included 337 adolescents and 876 mothers who delivered live-born, singleton infants in the Maternity and Infant Care Program at the Minneapolis Health Department between 1980-1982. Whites and blacks on the average experienced menarche 1-2 years earlier than the Southeast Asians although age of first pregnancy was 2 years later for the Southeast Asians. In spite of the significantly later ages of entry into prenatal care, lower weight gains, and hematocrits among the Southeast Asians, compared to the white and black populations, overall height-weight status on admission compared favorably with whites and blacks. The virtual absence of alcohol and tobacco consumption among the Southeast Asians may in fact contribute to the generally favorable Apgar scores, length of gestation, and birth weights. The high frequencies of alcohol and tobacco consumption among white adolescents during pregnancy suggest the need for more intervention to discourage smoking in this population. Further, the potential adoption of these substances needs to be discouraged among the Southeast Asian adolescents. While 2-4% of the whites, blacks and Hmong adolescents experienced eclampsia, 1% of the older Hmong mothers and none of the other Southeast Asians experienced eclampsia. The most frequent complication for all groups was perineal laceration.  相似文献   
70.
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