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191.
To develop a preoperative anxiety scale (YPAS) for children undergoing surgery, 21 specific behaviors indicating anxiety were defined within five domains (activity, emotional expressivity, state of arousal, vocalization, and use of adults). A reliability Kappa analysis revealed that inter-observer agreement ranged from .66 to .94, while intra-observer Kappa ranged from .66 to .91. Validity analysis between a Visual Analog Scale and the YPAS revealed an r of .59 for entering the operating room. Multiserial analysis comparing the YPAS to the Vernon Anxiety Scale ranged from .61 to .64. Showing good to excellent observer reliability and validity, the YPAS proves to be an appropriate tool for studying children's responses in preoperative settings. As such, the new assessment instrument should be of interest to clinical and research neuropsychologists who need to assess a child's anxiety level prior to the undertaking of a given surgical procedure.  相似文献   
192.
Ninety-four prenatally cocaine-exposed and 50 non-cocaine-exposed infants were enrolled at birth and seen at 3,6, and 12 months. Applying a recently developed model (Cicchetti&Nelson, 1994) produced four independent groups: those infants assessed at birth only (n=61), those returning for at least one (n=29) or two (n=15) assessments after birth, and those returning for all three (n=35). Among those infants having all follow-up assessments, cocaine-exposed infants showed significantly lower psychomotor performance on the Bayley Scales of Infant Development (BSID) than did non-exposed infants. Results approached statistical significance for mental development. Except for birthweight (cocaine-exposed infants weighed significantly less), none of a wide range of maternal, perinatal, or neurobehavioral demographic variables biased study results or the generalization of findings to the total sample from those who returned for all visits.  相似文献   
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194.
Head-mounted video cameras (with and without an eye camera to track gaze direction) are being increasingly used to study infants’ and young children's visual environments and provide new and often unexpected insights about the visual world from a child's point of view. The challenge in using head cameras is principally conceptual and concerns the match between what these cameras measure and the research question. Head cameras record the scene in front of faces and thus answer questions about those head-centered scenes. In this “Tools of the Trade” article, we consider the unique contributions provided by head-centered video, the limitations and open questions that remain for head-camera methods, and the practical issues of placing head cameras on infants and analyzing the generated video.  相似文献   
195.
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   
196.
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   
197.
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   
198.
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   
199.
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   
200.
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   
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