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81.
This study examined the relation between ethnically based rejection sensitivity and academic achievement in a sample of 936 immigrant students in Germany and Switzerland. The theory of race‐based rejection sensitivity that originated in North America was extended to immigrant students in Europe. The rough political climate against immigrants in Europe makes it probable that immigrant youth face particular difficulties and are affected by ethnically based rejection sensitivity, at least as much as—or even more than—minority youth in the United States. Using a standardized literacy performance test and multilevel analyses, we found that ethnically based rejection sensitivity was negatively related to academic achievement for immigrant students. This relation was partially mediated by a strong contingency of the students' self‐worth on the heritage culture, as well as by a low number of native German or Swiss majority‐group friends. We interpret these processes as immigrant students' efforts to cope with ethnically based rejection sensitivity by retracting into their heritage culture and avoiding majority‐group contact, which unfortunately, however, at the same time also results in lower academic achievement. Copyright © 2014 John Wiley & Sons, Ltd.  相似文献   
82.
A recalibration response shift will cause the patient to think about a self-report measure’s response options differently after a health state change. Commonly assessed using the retrospective-pretest design (“then-test”), recent guidelines suggest adjusting then-test estimates for competing explanations. This prospective longitudinal study investigated recalibration response shift after adjusting for implicit theories of change in patients undergoing spinal surgery. The Oswestry Disability Index (ODI) and Short Form-36 (SF-36) were collected before surgery and at 6 weeks and 3 months after spinal decompression surgery. Then-tests of the measures were also collected at all post-tests. Recalibration response shift was operationalized as the then-minus-pre difference score on the evaluative SF-36. Implicit theories of change were operationalized as the then-minus-pre difference score on the perception-based ODI. Improved vs. No-Effect patient groups were compared using the Minimally Important Difference (±15 points) as a cut-off on the Visual Analogue Scale (VAS) items for back and leg pain. Logistic regression analyses investigated whether recalibration response shift had an independent effect distinguishing patient groups, after adjusting for implicit theories of change. The sample (baseline n?=?169, mean age 52, 39 % female) was well-educated, and 1/3 were working. All then-minus-pre difference scores were non-zero at each time point and were stable over time. In the adjusted models distinguishing Improved versus No Effect groups, then-minus-pre ODI difference scores were significant in the majority of the adjusted models at all timepoints, but only one then-minus-pre SF-36 difference score—for physical functioning recalibration—was significant and only at 6-weeks post-surgery. This suggests that implicit theories of change bias the estimation of post-surgical outcomes, but that recalibration response shift biased only the estimation of physical functioning and only at 6 weeks post-surgery. Recalibration response shift and implicit theories of change can both be sources of bias in patient-reported outcome assessment. Our findings suggest that implicit theories of change are a greater threat to validity in this patient sample. Future research using the then-test should control for implicit theories of change to minimize misspecification of effects.  相似文献   
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The heterozygote reeler mouse (HRM) shows many neuroanatomical and biochemical features that are also present in some human cognitive disorders, such as schizophrenia. In the present study, hippocampal dependent plasticity and cognitive function of the HRM were characterized in detail in an attempt to reveal phenotypic functional differences that result from Reelin haploinsufficiency. The HRM and wild type mice show similar levels of overall activity, coordination, thermal nociception, startle responses, and anxiety-like behavior. In addition, both genotypes show similar shock threshold, identical cued freezing behavior and comparable spatial learning in Morris water maze tasks. However, a significant reduction in contextual fear conditioned learning was observed in the HRM. Electrophysiological studies in hippocampal CA1 synapses revealed a plethora of differences between genotypes. The HRM exhibits reduced field excitatory postsynaptic potentials in responses to similar synaptic inputs, lowered paired pulse facilitation ratio and impaired long-term depression and tetanus-induced long-term potentiation (LTP). Also, deficits were detected in LTP elicited by theta burst stimulation or by a whole cell pairing protocol. These physiologic differences could not be accounted for by changes in the overall amount of glutamate receptor subunits. In addition, it was determined that network-driven excitatory and inhibitory activities recorded in CA1 pyramidal neurons showed that the HRM had comparable amplitude and frequency of spontaneous excitatory postsynaptic currents, but a marked reduction in spontaneous inhibitory postsynaptic currents. Thus, the HRM exhibits a specific hippocampal-dependent learning deficit accompanied with a pronounced impairment of hippocampal plasticity and functional inhibitory innervation.  相似文献   
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Socially housed mice with cytotoxic lesions of the hippocampus do not exhibit social recognition memory 30 min following exposure to a juvenile mouse, however the social recognition memory of singly housed rats is unimpaired. The present study tests the hypothesis that social housing of rats could render social recognition memory hippocampally dependent as seen for mice. Rats were housed with juveniles or with adults. Two social recognition one-animal tests paralleling those used with mice were carried out. Seven social discrimination two-animal tests were also given. Sham operated and hippocampally lesioned rats had normal social memory at 30 min whether socially housed for 24, 48 h, 7 or 8 days prior to testing. These findings support other results indicating the hippocampus proper is not required for normal social memory in rats. In a final experiment, rats socially housed in groups of three since weaning, were tested for 30 min and 24 h social memory. Unlike mice, rats socially housed throughout life exhibited social memory only at 30 min, but not at 24 h. Manipulations that extend social memory in rats may be required to render social memory hippocampally dependent or rats and mice may differ in the neural mediation of social memory.  相似文献   
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Serious sequelae of youth depression, plus recent concerns over medication safety, prompt growing interest in the effects of youth psychotherapy. In previous meta-analyses, effect sizes (ESs) have averaged .99, well above conventional standards for a large effect and well above mean ES for other conditions. The authors applied rigorous analytic methods to the largest study sample to date and found a mean ES of .34, not superior but significantly inferior to mean ES for other conditions. Cognitive treatments (e.g., cognitive-behavioral therapy) fared no better than noncognitive approaches. Effects showed both generality (anxiety was reduced) and specificity (externalizing problems were not), plus short- but not long-term holding power. Youth depression treatments appear to produce effects that are significant but modest in their strength, breadth, and durability.  相似文献   
89.
Memory reactivation has not been systematically studied with infants older than 1 year. Currently, three experiments examined the effects of a reactivation treatment (priming) on retention throughout the second postnatal year. Fifteen- and 18-month-olds learned an operant train task, forgot it, received a 2-min or 10-s prime, and later were tested for retention. Although the longer prime was effective for 15-month-olds, 18-month-olds required the shorter prime (Experiment 1). The memory was reactivated after delays two (18 months) and three (15 months) times longer than infants originally remembered it (Experiment 2). The reactivated memory was forgotten as fast as the original memory after the 2-min prime and twice as fast after the 10-s prime (Experiment 3). The fact that reactivation changes quantitatively but not qualitatively throughout infancy suggests that the same mechanism mediates it at all ages. These findings have major implications for the impact of early experience on cognitive development.  相似文献   
90.
This study examines whether availability of mental health resources in the county of residence is associated with subsequent suicidal behavior after a previous suicide attempt. Among 10,922 individuals who attempted suicide in Colorado between 1998 and 2002, residence in a county that offered a minimum safety-net of mental health services significantly reduced the risk of suicidal behavior for at least 1 year after the index attempt. Safety-net services included mental health treatment, crisis treatment, and case management. These results suggest one strategy for prevention of suicidal behavior that could inform state-level health policy development and resource allocation.  相似文献   
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