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31.
The “co-familiality” criterion for an endophenotype has two requirements: (1) clinically unaffected relatives as a group should show both a shift in mean performance and an increase in variance compared with controls; (2) performance scores should be heritable. Performance on the antisaccade task is one of several candidate endophenotypes for schizophrenia. In this paper we examine whether the various measures of performance on the standard version of the antisaccade task meet the co-familiality criterion for an endophenotype. The three measures of performance—reflexive saccade errors, latency of correct antisaccades, and gain—show a wide range of effect sizes and variance ratios as well as evidence of significant or near significant heterogeneity. The estimated mean effect sizes [Cohen’s d: error rate: 0.34 (SD: 0.29); latency: 0.33 (SD: 0.30); gain: 0.54 (SD: 0.38)] are significantly greater than 0, but the magnitude of the departures from 0 is relatively small, corresponding to modest effect sizes. The width of the 95% confidence intervals for the estimated effect sizes (error rate: 0.2–0.49; latency: 0.17–0.50; gain: 0.23–0.85) and the coefficients of variation in effect sizes (error rate: 85.3%; latency: 90.9%; gain: 68.4%) reflect heterogeneity in effect sizes. The effect sizes for error rate showed statistically significant heterogeneity and those for latency (P = .07) and gain (P = .09) showed a trend toward heterogeneity. These results indicate that the effect sizes are not consistent with a single mean and that the average effect size may be a biased estimate of the magnitude of differences in performance between relatives of schizophrenics and controls. Relatives of schizophrenics show a small but significant increase in variance in error rate, but the confidence interval is broad, perhaps reflecting the heterogeneity in effect size. The variance ratios for latency and gain did not differ in relatives of schizophrenics and controls. Performance, as measured by error rate, is moderately heritable. The data do not provide compelling support for a consistent shift in mean or variance in relatives of schizophrenia patients compared with nonpsychiatric controls, both of which are required for a major gene involved in co-familial transmission. This set of findings suggests that although intra-familial resemblance in antisaccade performance is due in part to genetic factors, it may not be related to a schizophrenia genotype. Based on the current literature, it would be premature to conclude that any of the measures of antisaccade performance unambiguously meets the co-familiality criterion for an endophenotype.  相似文献   
32.
Using a stratified sample of Canadian adolescents residing in Ontario (n = 2,154) time use patterns and perceptions of time pressure are explored to determine gender differences among younger (12–14 years) and older adolescents (15–19 years). For both age groups, girls report a higher total workload of schoolwork, domestic activities and paid employment and spend more time on personal care while boys have more free time, especially during early adolescence. Feelings of time pressure for teens increase with age and are significantly higher for girls in both age categories. Gender differences are less pronounced on school days when time is fairly structured, but become more consistent with traditional gender schema on the weekend when time use is more discretionary.  相似文献   
33.
Using data from the National Education Longitudinal Study, the authors examined relations between educational, civic, and occupational success in young adulthood and the duration and intensity of participation in organized activities during high school. They also examined these relations as a function of sponsorship (i.e., school- vs. community-sponsored organized activities). They found that youths who participated in organized activities for 2 years demonstrated more favorable educational and civic outcomes in young adulthood than those who participated for 1 year. More intensive participation was also associated with greater educational, civic, and occupational success in young adulthood--particularly among youths who participated in activities for 2 years. Educational attainment often mediated the relations between temporal measures of participation and young adult civic and occupational outcomes. With the exception of analyses examining occupational success, findings varied little as a function of sponsorship. Of note, analyses revealed that both temporal measures of participation were positively associated with young adult outcomes as many as 8 years after high school.  相似文献   
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Sex differences in subjective distress to violations of trust in a close relationship were observed among Mexican American men and women. Imagining a partner’s emotional infidelity and other female-linked violations (for example, a partner who no longer desires to work) distressed a larger percentage of women than men. In contrast, imagining a partner’s sexual infidelity and other male-linked violations (for example, a partner who no longer makes an effort to look physically attractive) distressed a larger percentage of men than women. The results from two studies provided compelling evidence against a social–cognitive explanation of the sex differences and for an evolutionary psychology explanation based on men and women responding to threats to their sex-linked mating strategies.  相似文献   
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The present study was an investigation of effects of emotional states on children's learning and memory for a short narrative. Happy, sad, or neutral moods were induced in 72 second-grade boys and girls by a standard affect induction procedure. This mood induction was accomplished either before or after they heard a story in which two protagonists encountered a variety of experiences having an affective character. For half of the subjects, the initial story event had a positive affective valence, and for half it was negative. Children's memory for events in the narrative was assessed immediately afterward, using measures offo free recall, cued recall, and recognition. Children recalled more affective content than neutral content, and boys recalled more than girls. Valence of the initial story item and sex of subject influenced the relationship between mood state and memory for story events. Under some conditions, positive moods reduced recognition accuracy for positive material. The findings suggest that simple patterns of mood-influenced memory found in previous studies are modified by factors such as characteristics of the learner and the organization of the material to be learned. The relationship between mood and memory thus appears to be more complex than previously recognized.This experiment was supported in part by a grant from the National Science Foundation (BNS-8308147) to John C. Masters. The authors wish to thank Bill Harris, Suzanne Chabaud, and Saneya Hassan for assistance in data collection and coding.  相似文献   
38.
Consideration will be given to a model developed by Rasch that assumes scores observed on some types of attainment tests can be regarded as realizations of a Poisson process. The parameter of the Poisson distribution is assumed to be a product of two other parameters, one pertaining to the ability of the subject and a second pertaining to the difficulty of the test. Rasch's model is expanded by assuming a prior distribution, with fixed but unknown parameters, for the subject parameters. The test parameters are considered fixed. Secondly, it will be shown how additional between- and within-subjects factors can be incorporated. Methods for testing the fit and estimating the parameters of the model will be discussed, and illustrated by empirical examples.  相似文献   
39.
Group climate and group development of the community meeting on a short-term inpatient psychiatric unit are examined. The Group Climate Questionnaire (GCQ) was administered to all staff and patients present at the weekly community meeting on an acute treatment unit in a teaching hospital over a 12-week period. Results show that staff and patients perceive the community meetings in relatively similar ways, that the group climate of a community meeting can attain a positive working state, and that, at times, the meeting can progress through developmental stages of group process. Behavioral observations support the GCQ as a measure of group interaction.The authors gratefully acknowledge the assistance of Mary Pat Donnelly with the statistical analyses and the cooperation of all staff and patients who participated in this study.  相似文献   
40.
The vocalizations of eight infants with Down syndrome were recorded longitudinally in relation to different social and non-social contexts. The infants were observed biweekly from 8 to 24 weeks and monthly up to 40 weeks. At each visit the infants were presented with their mother, a female stranger, and a rattle puppet, each alternately active and passive. Each condition lasted 60 sec. The results showed that by 4 months of age, the infants produced different types of vocal sounds in relation to environmental contexts. They produced significantly more melodic (speechlike) sounds, vocalic (non-speechlike) sounds, and emotional (crying, laughing and fussing) sounds when facing people than objects. By 6 months of age, these utterances began to be distinguished between mother and female stranger and active and passive adults. However, within the communicative context the overall amount of vocalic (non-speechlike) sounds produced was larger than the amount of melodic (speechlike) sounds. It is suggested that this low output of melodic sounds in the overall vocal production of these infants may adversely affect the development of more appropriate vocal behaviour.  相似文献   
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