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201.
Human visual object recognition is multifaceted and comprised of several domains of expertise. Developmental relations between young children's letter recognition and their 3-dimensional object recognition abilities are implicated on several grounds but have received little research attention. Here, we ask how preschoolers' success in recognizing letters relates to their ability to recognize 3-dimensional objects from sparse shape information alone. Seventy-three 2 1/2 to 5-year-old children completed a “Letter Recognition” task, measuring the ability to identify a named letter among 3 letters, and a “Shape Caricature Recognition” task, measuring recognition of familiar objects from sparse, abstract information about their part shapes and the spatial relations among those parts. Children also completed a control “Shape Bias” task, in which success depends on matching exact shapes but not on building an internal representation of the configuration of features characteristic of an object category or letter. Children's success in letter recognition was positively related to their shape caricature recognition scores, but not to their shape bias scores. The results suggest that letter recognition builds upon developing skills in attending to and representing the relational structure of object shape, and that these skills are common to both 2-dimensional and 3-dimensional object perception.  相似文献   
202.
Each year, 14,000 children are diagnosed with cancer in the United States. Prolonged, intensive treatment regimens disrupt the entire family system, but effects on siblings are poorly understood. In this preliminary investigation, we employed a risk and resistance framework to study adjustment among 30 siblings (aged 10–17) of children undergoing cancer treatment. We examined whether or not objective stress associated with the cancer experience (contextual threat) predicted sibling distress and explored demographic and disease-related predictors of sibling adjustment. Contextual threat was positively associated with sibling-reported distress, independent of sibling age, gender, birth order relative to the child with cancer, and cancer treatment intensity. From among the demographic and disease-related factors, only younger birth order relative to the child with cancer was independently associated with sibling distress. These results suggest that a subset of siblings may be at increased risk for elevated distress in the face of their brother’s or sister’s illness.  相似文献   
203.
This study explored the effects of bullying victimization (BV), as a Type II traumatic stressor, on intelligence quotient (IQ), posttraumatic stress disorder (PTSD), and complex PTSD symptoms. Participants were 390 African American and Iraqi refugee adolescents. Measures of BV, cumulative life trauma, PTSD, discrimination, and IQ were administered. Correlational, multilevel regression, and path analyses were conducted. BV, independent of cumulative trauma, and discrimination were found to have significant direct effects on increased PTSD symptoms and significant direct and indirect negative effects on perceptual reasoning, processing speed, and working memory. BV was also associated with increases in the discrepancy between perceptual reasoning and verbal comprehension. The implications of these results for the prevention and treatment of bullying victims are discussed.  相似文献   
204.
Reunion behavior following stressful separations from caregivers is often considered the single most sensitive clue to infant attachment patterns. Extending these ideas to middle childhood/early adolescence, we examined participants' neural responses to reunion with peers who had previously excluded them. We recorded event‐related potentials among nineteen 11‐ to 15‐year‐old youth previously classified on attachment interviews (11 secure and 8 insecure‐dismissing) while they played a virtual ball‐toss game (Cyberball) with peers that involved fair play, exclusion and reunion phases. Compared to secure participants, dismissing participants displayed a greater increment in the N2 during reunion relative to fair play, a neural marker commonly linked to expectancy violation. These data suggest a greater tendency toward continued expectations of rejection among dismissing children, even after cessation of social exclusion. In turn, the link between self‐reported ostracism distress and neural signs of negative expectancy at reunion was moderated by attachment, such that self‐reports were discordant with the neural index of expectancy violation for dismissing, but not for secure children. A video abstract of this article can be viewed at http://www.youtube.com/watch?v=qzoRel5c-4s .  相似文献   
205.
We examined cross-sectional differences and longitudinal changes in episodic memory performance related to impending death among a group of very old people, aged 90–101 years. Participants were assessed at 3 measurement points across a 6-year interval. Three groups were identified: those who survived the entire follow-up period (n =40), those who died before the first follow-up (n =44), and those who died after the first follow-up (n =14). Participants completed a battery of episodic memory tasks consisting of face recognition, word recognition, word recall, and object recall with selective reminding. Those who survived performed better than those who were going to die in object recall at baseline. A Cox regression analysis, controlling age, revealed that object recall performance was significantly related to subsequent mortality status. Longitudinal analyses demonstrated significant 3-year decline for both face recognition and object recall, but no evidence of differential decline as a function of mortality group. Thus, longitudinal changes in memory preceding death were not as pronounced as the corresponding cross-sectional differences in this very old sample. In general, the results suggest that mortality-related memory deficits are present in extreme old age, although these deficits are relatively small and task-specific.  相似文献   
206.
We examined the relationship between type 2 diabetes mellitus and cognitive function in a population-based sample of very old people. The sample comprised 338 persons, aged 80-93 years (mean age 83.5 years), of whom 70 persons had type 2 diabetes mellitus. Measures of cognitive functioning included tests of perceptual speed, visuo-spatial ability, inductive reasoning, short-term memory, semantic memory, episodic memory, and the Mini-Mental State Examination. Regression analyses showed that type 2 diabetes mellitus duration was related to test performance across all cognitive domains, with the exception of short-term memory, such that longer duration was associated with lower test performance. When cases with dementia were excluded from the sample, further analyses showed that diabetes duration was not associated with cognitive test performance. This indicates that diabetes is not related to lower cognitive function in the general population of non-demented old people. Diabetes, however, increases the risk for cerebrovascular incidents, like stroke, that may contribute to vascular dementia.  相似文献   
207.
This experiment sought further support for the view that early stage Alzheimer's disease (AD) disrupts cognitive structures that cast experience into a temporal framework. Forty participants, evenly divided between normal elderly (NE) and persons diagnosed with mild AD, viewed 19 lists of 14 pictures each. Following the presentation of each list participants were asked to identify the most recently experienced picture (target) from 3 pictures. A second stimulus was a picture never previously seen; the third picture was a distracting item that had appeared in the list on either one or three occasions. The results show that whereas choice accuracy of the NE group remained largely unimpaired regardless of the delay between the target and the judgment task or the frequency of the distractor, the AD participants exhibited large and profound deficits in temporal judgments, especially when distractor frequency was greater than the more recent event. In effect, the AD group relied on how often an event occurred rather than the time of its occurrence. This finding is consistent with previous research that found AD patients deficient in forming a temporal representation of their experience.  相似文献   
208.
Our aim in this paper is to bring attention to the applied value of collaborative memory research in aging. At this time, much collaborative memory research focuses on the negative effects of collaboration in younger adults, and is primarily basic in nature. Here, we highlight the positive effects of collaboration that have received less attention, with a particular emphasis on the applied value of these effects in older adults. We first review studies to show that recalling in a group improves later individual recall and reduces memory errors in older adults. We then outline a four-step approach towards bridging laboratory and applied collaborative memory research, which involves: (1) complementing traditional paradigms with more ecologically valid paradigms, (2) evaluating these paradigms in applied settings, (3) adapting these paradigms for use with cognitively intact and cognitively impaired populations, and (4) modifying these paradigms to examine the neural systems that operate during collaborative recall.  相似文献   
209.
Development as a dynamic system   总被引:1,自引:0,他引:1  
Development is about creating something more from something less, for example, a walking and talking toddler from a helpless infant. One current theoretical framework views the developmental process as a change within a complex dynamic system. Development is seen as the emergent product of many decentralized and local interactions that occur in real time. We examine how studying the multicausality of real-time processes could be the key to understanding change over developmental time. We specifically consider recent research and theory on perseverative reaching by infants as a case study that demonstrates this approach.  相似文献   
210.
Research on HIV/AIDS interventions indicates that many heterosexual women implement the construct of trust when deciding if preventive measures are necessary. The personal construct model evaluated in this experiment proposes that young women's choice to resist changing from a trust to a nontrust position can be understood in terms of the relationship between their constructs and the hierarchical organization of their construct subsystems. Findings suggest that women with well-defined networks of implications on their nonpreferred pole of the trust/mistrust construct resist HIV-preventive messages that require them to mistrust their partner because the proposed change will involve successive use of subordinate constructs that are incompatible with each other.  相似文献   
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