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221.
Capuchin monkeys (Cebus apella) matched a variety of rodlike figures, distinguishable only by their central portions. The monkeys were then tested for perceptual completion rules by examining which comparison figures they would choose as matching the sample with the critical central portion occluded by a horizontal belt. In Experiment 1, the monkeys overwhelmingly chose a straight rod over disconnected rods and rods having irregular shapes at their center, irrespective of the presence-absence of common motion of visible parts of the samples. The monkeys chose a connected rod for relatable rods and disconnected rods for non-relatable ones in Experiment 2. In Experiments 3 and 4, some of the monkeys chose rods specified by the global regularity of the contour, whereas others did not. Experiment 5 showed that humans and capuchin monkeys basically follow similar perceptual rules in completing occluded contours, but the global regularity rule may be stronger in humans.  相似文献   
222.
Humans and pigeons were trained to discriminate between 2 views of actual 3-D objects or their photographs. They were tested on novel views that were either within the closest rotational distance between the training views (interpolated) or outside of that range (extrapolated). When training views were 60 degrees apart, pigeons, but not humans, recognized novel views of actual objects better than their pictures. Further, both species recognized interpolated views of both stimulus types better than extrapolated views, but a single distinctive geon enhanced recognition of novel views only for humans. When training views were 90 degrees apart, pigeons recognized interpolated views better than extrapolated views with actual objects but not with photographs. Thus, pigeons may represent actual objects differently than their pictures.  相似文献   
223.
Performance on a covert visual attention task is compared between a group of adults with developmental dyslexia (specifically phonological difficulties) and a group of age and IQ matched controls. The group with dyslexia were generally slower to detect validly-cued targets. Costs of shifting attention toward the periphery when the target was invalidly cued were significantly higher for the group with dyslexia, while costs associated with shifts toward the fovea tended to be lower. Higher costs were also shown by the group with dyslexia for up-down shifts of attention in the periphery. A visual field processing difference was found, in that the group with dyslexia showed higher costs associated with shifting attention between objects in they LVF. These findings indicate that these adults with dyslexia have difficulty in both the space-based and the object-based components of covert visual attention, and more specifically to stimuli located in the periphery.  相似文献   
224.
Approximately 800 youths from the Children in the Community Study (Cohen & Cohen, 1996) have been assessed prospectively for over 20 years to study personality disorders (PDs) in adolescents and young adults. In this article we evaluate the Children in the Community Self-Report (CIC-SR) Scales, which were designed to assess DSM-IV PDs using self-reported prospective data from this longitudinal sample. To evaluate convergent validity, we assessed concordance between the CIC-SR Scales and the Structured Clinical Interview for DSM-IV Personality Disorders (SCID-II; First, Gibbon, Spitzer, Williams, & Benjamin, 1995) in 644 participants at mean age 33. To assess predictive validity, we used CIC-SR Scales at mean age 22 to predict subsequent CIC-SR and SCID-II Personality Questionnaire scores at mean age 33. In these analyses the CIC-SR Scales matched or exceeded benchmarks established in previous comparisons between self-report instruments and structured clinical interviews. Unlike other self-report scales, the CIC-SR did not appear to overestimate diagnoses when compared with SCID-II clinical diagnoses.  相似文献   
225.
The aim of this study was to examine differences in responses to the Caregiver Strain Questionnaire (CGSQ) between African American and White caregivers of children with emotional and behavioral challenges. Significant item- and scale-level differences were detected across groups with African Americans consistently reporting less strain. We examined whether these differences were more likely due to nonequivalent measurement than to real differences in the experience of caregiver strain. Confirmatory factor analysis showed that the model fit the data well for both racial groups, but there were some differences in structural components. Internal consistency was equivalent across the groups. In an examination of criterion validity, regression analyses showed that African American caregivers experienced a slower rate of increase in objective caregiver strain at a given increase in child internalizing problems. No other race differences were found in the regression analyses. In general, we conclude that the CGSQ can be useful for detecting caregiver strain and identifying family support needs for both White and African American caregivers. Differences across groups in reports of caregiver strain, however, call for more research on racial differences in the impact on the family of caring for a child with emotional and behavioral disorders.  相似文献   
226.
The World Wide Web (WWW) poses a distinct capability to offer interventions tailored to the individual's characteristics. To fine tune the tailoring process, studies are needed to explore how Internet accessibility and usage are related to demographic, psychosocial, behavioral, and other health related characteristics. This study was based on a cross-sectional survey conducted on 2373 7th grade students of various ethnic groups in Southern California. Measures of Internet use included Internet use at school or at home, Email use, chat-room use, and Internet favoring. Logistic regressions were conducted to assess the associations between Internet uses with selected demographic, psychosocial, behavioral variables and self-reported health statuses. The proportion of students who could access the Internet at school or home was 90% and 40%, separately. Nearly all (99%) of the respondents could access the Internet either at school or at home. Higher SES and Asian ethnicity were associated with higher internet use. Among those who could access the Internet and after adjusting for the selected demographic and psychosocial variables, depression was positively related with chat-room use and using the Internet longer than 1 hour per day at home, and hostility was positively related with Internet favoring (All ORs = 1.2 for +1 STD, p < 0.05). Less parental monitoring and more unsupervised time were positively related to email use, chat-room use, and at home Internet use (ORs for +1 STD ranged from 1.2 to 2.0, all p < 0.05), but not related to at school Internet use. Substance use was positively related to email use, chat-room use, and at home Internet use (OR for "used" vs. "not used" ranged from 1.2 to 4.0, p < 0.05). Self-reported health problems were associated with higher levels of Internet use at home but lower levels of Internet use at school. More physical activity was related to more email use (OR = 1.3 for +1 STD), chat room use (OR = 1.2 for +1 STD), and at school ever Internet use (OR = 1.2 for +1 STD, all p < 0.05). Body mass index was not related to any of the Internet use-related measures. In this ethnically diverse sample of Southern California 7(th) grade students, 99% could access the Internet at school and/or at home. This suggests that the Internet is already a potential venue for large scale health communication studies. Adolescents with more psychosocial risk factors or detrimental health behaviors were more likely to use the Internet. Therefore, if used properly, Internet interventions could effectively address the high risk populations. Additional research is needed to gain a more complete understanding of the positive and negative consequences of Internet use among adolescents.  相似文献   
227.
Infants' sensitivity to social contingencies was assessed. In Study 1, 1-month-old infants and their mothers interacted face-to-face in three types of imperfect contingent interactions: Normal, Non-Contingent and Imitation. One-month-old infants did not discriminate these conditions. In Study 2, 3-month-old infants were tested as in Study 1. At 3 months of age, infants gazed reliably longer in the Imitation condition and smiled reliably more in the Normal than in the Non-Contingent and Imitation interactions. These findings suggest a developmental transition in the sensitivity to social contingencies between 1 and 3 months of age. The relationship between the developing sensitivity to social contingencies and social cognition is discussed.  相似文献   
228.
We review recent advances in the understanding of the mechanisms of change that underlie cognitive development. We begin by describing error-driven, self-organizing and constructivist learning systems. These powerful mechanisms can be constrained by intrinsic factors, other brain systems and/or the physical and social environment of the developing child. The results of constrained learning are representations that themselves are transformed during development. One type of transformation involves the increasing specialization and localization of representations, resulting in a neurocognitive system with more dissociated streams of processing with complementary computational functions. In human development, integration between such streams of processing might occur through the mediation of language.  相似文献   
229.
The present work investigated mechanisms by which Whites' prejudice toward Blacks can be reduced (Study 1) and explored how creating a common ingroup identity can reduce prejudice by promoting these processes (Study 2). In Study 1, White participants who viewed a videotape depicting examples of racial discrimination and who imagined the victim's feelings showed greater decreases in prejudice toward Blacks than did those in the objective and no instruction conditions. Among the potential mediating affective and cognitive variables examined, reductions in prejudice were mediated primarily by feelings associated with perceived injustice. In Study 2, an intervention designed to increase perceptions of a common group identity before viewing the videotape, reading that a terrorist threat was directed at all Americans versus directed just at White Americans, also reduced prejudice toward Blacks through increases in feelings of injustice.  相似文献   
230.
Resilient teachers: resisting stress and burnout   总被引:5,自引:0,他引:5  
In Australia, the incidence of teacher stress and burnout has caused serious concern. Many studies of teacher stress have focused on the dysfunctional strategies of individual teachers – in other words they have adopted a deficit approach to the problem with the focus firmly fixed on whats going wrong. From this perspective, the failure of some teachers to cope has generally been defined as a personal rather than an institutional weakness and the solutions that have been promoted have been largely palliative or therapeutic. The study reported in this paper adopted a different approach to the question of teacher stress and burnout. Instead of asking whats going wrong we asked why are some teachers able to cope successfully with the same kinds of stressors that appear to defeat others – in other words, we looked at whats going right.  相似文献   
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