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ABSTRACT

Research in older Caucasians has demonstrated that cognitive activity is related to cognitive function in late adulthood. Knowledge of this association is limited in older minority populations. We examined the relation of cognitive activity and access to cognitive resources, with cognitive function in a group of 108 older African Americans. We constructed two scales to measure the frequency of cognitive activity and the presence of resources that promote cognitive activity during early and late life. Both measures had high internal consistency and the cognitive activity scale had adequate temporal stability over a 4-week interval. In analyses that controlled for age and education, more frequent lifetime cognitive activity was related to current cognitive function, but lifetime cognitive resources only approached significance. The results suggest that both measures are psychometrically sound in a minority population and that lifetime cognitive activity may contribute to current cognitive function in African Americans.  相似文献   
133.
Using a speeded retrieval procedure, we investigated time-of-day effects in automatic and controlled retrieval. Morning-type adults were tested at either peak (early morning) or off-peak (late afternoon) times on a speeded implicit (Experiment 1) or explicit (Experiment 2) stem completion task. In Experiment 1, retrieval strategies were identified by changes in response speed between a practice phase with rapid retrieval and an implicit memory test phase. Performance based on controlled retrieval (shown by slowdown participants) showed more priming at peak than at off-peak times of day, a finding confirmed in Experiment 2, in which the participants were given intentional retrieval instructions when the materials switched. In contrast, performance based on automatic retrieval (shown by nonslowdown participants) did not differ across peak and off-peak times. The finding suggests a robust synchrony effect in controlled retrieval, but not in automatic retrieval, which does not appear to vary across the day.  相似文献   
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The development of imitation during the second year of life plays an important role in domains of sociocognitive development such as language and social learning. Deficits in imitation ability in persons with autism spectrum disorder (ASD) from toddlerhood into adulthood have also been repeatedly documented, raising the possibility that early disruptions in imitation contribute to the onset of ASD and the deficits in language and social interaction that define the disorder. This study prospectively examined the development of imitation between 12 and 24 months of age in 154 infants at familial risk for ASD and 78 typically developing infants who were all later assessed at 36 months for ASD or other developmental delays. The study established a developmental measure of imitation ability and examined group differences over time, using an analytic Rasch measurement model. Results revealed a unidimensional latent construct of imitation and verified a reliable sequence of imitation skills that was invariant over time for all outcome groups. Results also showed that all groups displayed similar significant linear increases in imitation ability between 12 and 24 months and that these increases were related to individual growth in both expressive language and ratings of social engagement but not in fine motor development. The group of children who developed ASD by age 3 years exhibited delayed imitation development compared with the low-risk typical outcome group across all time-points, but were indistinguishable from other high-risk infants who showed other cognitive delays not related to ASD.  相似文献   
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Although research on the influence of neighborhoods on the development of youth is growing, few researchers have examined the impact of neighborhood quality on physiological outcomes or across gender. The present experiment examined gender differences in the association of neighborhood quality and cardiovascular reactivity (increased blood pressure, BP, in response to stress) among 77 healthy African American adolescents (46% male; M age = 14 years). Participants took part in a cold-face stimulus task to determine reactivity scores. After controlling for baseline BP, family income, and parental education, poorer neighborhood quality was associated with increases in both systolic and diastolic BP to the cold-face task for females, and decreases in BP for males. Adolescents’ reports of life stress and support from family members did not explain the differential effect of neighborhood quality across gender. Implications for future research are discussed.  相似文献   
139.
Durbin CE  Wilson S 《心理评价》2012,24(3):647-660
This study examined the convergent validity of maternal reports of child emotion in a sample of 190 children between the ages of 3 and 6. Children completed a battery of 10 emotion-eliciting laboratory tasks; their mothers and untrained na?ve observers rated child emotions (happiness, surprise, fear, sadness, and anger) following each task, and trained coders rated videotapes of each task for the same emotions. Consistent with studies using other designs, maternal reports demonstrated weak to moderate convergence with the other rating methods. Extending prior research, a number of maternal characteristics (particularly lifetime psychiatric diagnoses and personality traits) were associated with their reports of child emotions in the lab, above and beyond the effects of objective coding and observer reports of child emotions. For some emotions, mothers' mental health and dispositional variables were more strongly related to their reports of the child's emotions than were objective indices of the child's observable emotional behavior.  相似文献   
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The growing emphasis on the importance of publishing scientific findings in the academic world has led to increasing prevalence of potentially significant publications in which scientific and ethical rigour may be questioned. This has not only hindered research progress, but also eroded public trust in all scientific advances. In view of the increasing concern and the complexity of research misconduct, the Committee on Publication Ethics (COPE) was established in 1997 to manage cases with ethical implications. In order to review the outcomes of cases investigated by COPE, a total of 408 cases that had been managed by COPE were successfully extracted and analysed with respect to 7 distinct criteria. The results obtained indicate that the number of ethical implications per case has not changed significantly (p?>?0.01) since the year COPE was instigated. Interestingly, the number of ethical cases, and to some extent, research misconduct, is not diminishing. Therefore, journal editors and publishers need to work closely together with COPE to inculcate adoption of appropriate research ethics and values in younger researchers while discouraging others from lowering standards. It is hoped that with a more concerted effort from the academic community and better public awareness, there will be fewer incidences of ethically and scientifically challenged publications. The ultimate aim being to enhance the quality of published works with concomittant public trust in the results.  相似文献   
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