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211.
The authors examined the Trauma Symptom Inventory's (TSI) ability to discriminate 88 student post-traumatic stress disorder (PTSD) simulators screened for genuine PTSD from 48 clinical PTSD-diagnosed outpatients. Results demonstrated between-group differences on several TSI clinical scales and the Atypical Response (ATR) validity scale. Discriminant function analysis using ATR revealed 75% correct patient classification but only 48% correct simulator classification, with an overall correct classification rate of 59% (positive predictive power [PPP] = .71; negative predictive power [NPP] = .51). Individual ATR cutoff scores did not yield impressive classification results, with the optimal cutoff (T score = 61) correctly classifying only 61% of simulators and patients (PPP = .66, NPP = .54). Although ATR was not developed as a malingered PTSD screen, instead serving as a general validity screen, caution is recommended in its current clinical use for detecting malingered PTSD.  相似文献   
212.
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   
213.
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   
214.
A battery of 17 neuropsychological tests (including the CERAD battery) and 17 psychometric ability tests were administered to a sample of 499 participants of the Seattle Longitudinal study who had been given the psychometric ability tests seven and 14 years earlier. The neuropsychological tests were projected into a 5-factor psychometric ability space by means of extension analysis. The concurrent regressions of the neuropsychology tests on the psychometric ability tests were then used to estimate neuropsychology test scores from the psychometric ability tests administered in 1984, 1991 and 1998. Neuropsychologists then rated the study participants as either normal, suspect or cognitively impaired in 1998. Changes in estimated test scores were computed over seven and fourteen years. Significant odds ratios between normal and cognitively impaired groups were found for all neuropsychological tests over the proximal period and for most tests over the 14-year period. Similar findings occurred for the odds ratios between the normal and suspect groups for the most proximal 7-year changes.  相似文献   
215.
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   
216.
Elder JH  Trithart S  Pintilie G  MacLean D 《Perception》2004,33(11):1319-1338
We used a visual-search method to investigate the role of shadows in the rapid discrimination of scene properties. Targets and distractors were light or dark 2-D crescents of identical shape and size, on a mid-grey background. From the dark stimuli, illusory 3-D shapes can be created by blurring one arc of the crescent. If the inner arc is blurred, the stimulus is perceived as a curved surface with attached shadow. If the outer arc is blurred, the stimulus is perceived as a flat surface casting a shadow. In a series of five experiments, we used this simple stimulus to map out the shadow properties that the human visual system can rapidly detect and discriminate. To subtract out 2-D image factors, we compared search performance for dark-shadow stimuli with performance for light-shadow stimuli which generally do not elicit strong 3-D percepts. We found that the human visual system is capable of rapid discrimination based upon a number of different shadow properties, including the type of the shadow (cast or attached), the direction of the shadow, and the displacement of the shadow. While it is clear that shadows are not simply discounted in rapid search, it is unclear at this stage whether rapid discrimination is acting upon shadows per se or upon representations of 3-D object shape and position elicited by perceived shadows.  相似文献   
217.
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   
218.
This article reviews the history, measures and principal findings of the Seattle Longitudinal Study. This study began in 1956 focusing upon age differences and age changes in cognitive abilities. Its sampling frame is a large HMO in the Pacific Northwest. The study has been expanded to investigate various influences on cognitive aging including, cognitive styles, personality traits, life styles, and family environment. Current interest is also in the early detection of risk for dementia. In addition, this article reports original analyses of the relation of personality dimensions to cognitive abilities (both concurrent and longitudinal). While personality remains relatively stable over the adult life span, modest proportions of variance are shared between various personality traits and the cognitive abilities.  相似文献   
219.
Throughout the U.S., state laws require professionals who work with children to report cases of suspected child abuse to child protection services. Both practically and conceptually, however, significant problems arise from a lack of clarity regarding the threshold that has been set for reporting. Specifically, there is no consensus as to what constitutes reasonable suspicion, and little direction for how mandated reporters should gauge their legal and professional responsibilities when they harbor suspicion. In this paper we outline the context of the problem, discuss the nature and scope of its conceptual underpinnings, and offer recommendations for moving towards a concrete, practical solution.  相似文献   
220.
Perceptual completion consists of bridging the gaps imposed by occlusion, such as perceiving the unity of center-occluded objects. It is unknown at present what developmental mechanisms underlie the emergence of functional perceptual completion in infancy. One current debate centers on the role of visible surface motion. According to a core-principles account, perceptual completion emerges simultaneously with the onset of motion discrimination, the sole determinant of unity percepts in infants. According to a contrasting constructivist account, motion discrimination is but one of several independent inputs to perceptual completion. In the present study, 2-month-old infants were tested for both unity perception and motion discrimination in partial-occlusion displays. Motion discrimination obtained under all conditions, even under circumstances in which infants were unable to perceive completion. Four-month-olds showed marked improvements in perceptual completion, most likely because of improvements in information integration. Taken together, these findings support a constructivist view of early perceptual and cognitive development.  相似文献   
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