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851.
This study examined whether the severity of cerebral white matter abnormalities (evident on MR images as white matter hyperintensities (WMH)) was related to the cognitive performance of 141 high-functioning older adults. The elderly showed the typical age decrement on measures of processing speed, working memory, and inhibition; however WMH severity was significantly related only to processing speed. The strength of this relationship was, however, influenced by the educational level of the participants, such that processing speed was more associated with WMH severity in less-educated than in well-educated participants. This is consistent with recent concepts of cognitive reserve, but does raise a question as to the underlying source of the cognitive decrement found in the sort of well-educated elders typically used in cognitive-aging studies.  相似文献   
852.
The authors reviewed the literature on mental health issues among clergy and other religious professionals, using electronic searches of databases of medical (Medline), nursing (CINAHL), psychology (PsycINFO), religious (ATLA), and sociological research (Sociofile). The existing research indicates the Protestant clergy report higher levels of occupational stress than Catholic priests, brothers, or sisters. Catholic sisters repeatedly reported the lowest work-related stress, whereas women rabbis reported the highest stress levels in various studies. Occupational stress appears to be a source of family stress among Protestant clergy--a factor which clergy and their spouses believe the denominational leadership should address. High levels of stress also have been found to be associated with sexual misconduct among clergy. The authors make several recommendations based on these and other findings they report in their review.  相似文献   
853.
Quality of life (QOL) is increasingly assessed in cancer patients. In this article, the authors examined the psychometric performance of a commonly used QOL questionnaire, the Quality of Life Questionnaire--Cancer 30 (QLQ-C30; N. K. Aaronson et al., 1993), in multiethnic cancer patients. Content validation studies in patients and clinicians identified possible new items. Multiple-group confirmatory factor analysis supported equivalent structure across ethnic groups (Caucasians and Asian/Pacific Islanders [APIs]). A higher order QOL factor appeared to directly affect functioning scales and symptom count. Exploratory factor analysis examined effects of new items. Ten factors were extracted, 6 consistent with the original instrument and 4 reflecting potentially new aspects of QOL: Positive Social Support, Coping, Existential Well-Being, and Sexuality/Intimacy. The QLQ-C30 appears appropriate for use in API cancer patients. Further work needs to ensure that it includes all important domains.  相似文献   
854.
A traditional management approach using indirect feedback was compared to an approach involving direct feedback for maintaining supervisory proficiency in observing and providing feedback to staff. Three supervisors participated in each condition. The first 3 supervisors then received direct feedback. Direct feedback was accompanied by high levels of performance relative to the indirect feedback protocol. The need for maintenance procedures with supervisors is discussed.  相似文献   
855.
In two H2(15)O PET scan experiments, we investigated the cerebral correlates of explicit and implicit knowledge in a serial reaction time (SRT) task. To do so, we used a novel application of the Process Dissociation Procedure, a behavioral paradigm that makes it possible to separately assess conscious and unconscious contributions to performance during a subsequent sequence generation task. To manipulate the extent to which the repeating sequential pattern was learned explicitly, we varied the pace of the choice reaction time task-a variable that is known to have differential effects on the extent to which sensitivity to sequence structure involves implicit or explicit knowledge. Results showed that activity in the striatum subtends the implicit component of performance during recollection of a learned sequence, whereas the anterior cingulate/mesial prefrontal cortex (ACC/MPFC) supports the explicit component. Most importantly, we found that the ACC/MPFC exerts control on the activity of the striatum during retrieval of the sequence after explicit learning, whereas the activity of these regions is uncoupled when learning had been essentially implicit. These data suggest that implicit learning processes can be successfully controlled by conscious knowledge when learning is essentially explicit. They also supply further evidence for a partial dissociation between the neural substrates supporting conscious and nonconscious components of performance during recollection of a learned sequence.  相似文献   
856.
The delta subunit of the GABA(A) receptor (GABA(A)R) is highly expressed in the dentate gyrus of the hippocampus. Genetic deletion of this subunit reduces synaptic and extrasynaptic inhibition and decreases sensitivity to neurosteroids. This paper examines the effect of these changes on hippocampus-dependent trace fear conditioning. Compared to controls, delta knockout mice exhibited enhanced acquisition of tone and context fear. Hippocampus-independent delay conditioning was normal in these animals. These results suggest that reduced inhibition in the dentate gyrus facilitates the acquisition of trace fear conditioning. However, the enhancement in trace conditioning was only observed in female knockout mice. The sex-specificity of this effect may be a result of neuroactive steroids. These compounds vary during the estrus cycle, can increase GABAergic inhibition, and have been shown to impair hippocampus-dependent learning. We propose that activation of GABA(A)Rs by neuroactive steroids inhibits learning processes in the hippocampus. Knockouts are immune to this effect because of the reduced neurosteroid sensitivity that accompanies deletion of the delta subunit. Relationships between neurosteroids, hippocampal excitability, and memory are discussed.  相似文献   
857.
Three methods of synthesizing correlations for meta-analytic structural equation modeling (SEM) under different degrees and mechanisms of missingness were compared for the estimation of correlation and SEM parameters and goodness-of-fit indices by using Monte Carlo simulation techniques. A revised generalized least squares (GLS) method for synthesizing correlations, weighted-covariance GLS (W-COV GLS), was compared with univariate weighting with untransformed correlations (univariate r) and univariate weighting with Fisher's z-transformed correlations (univariate z). These 3 methods were crossed with listwise and pairwise deletion. Univariate z and W-COV GLS performed similarly, with W-COV GLS providing slightly better estimation of parameters and more correct model rejection rates. Missing not at random data produced high levels of relative bias in correlation and model parameter estimates and higher incorrect SEM model rejection rates. Pairwise deletion resulted in inflated standard errors for all synthesis methods and higher incorrect rejection rates for the SEM model with univariate weighting procedures.  相似文献   
858.
The impacts of New Hope, a program to increase parent employment and reduce poverty, were measured 5 years after parents were randomly assigned to program or control groups. New Hope had positive effects on children's school achievement, motivation, and social behavior, primarily for boys, across the age range 6-16. In comparison to impacts measured 2 years after program onset, effects on achievement were robust, but effects on social behavior were reduced. The program produced improvements in family income and use of organized child care and activity settings, suggesting possible pathways by which the New Hope package of policies influenced children's behavior.  相似文献   
859.
Utterances expressing generic kinds ("birds fly") highlight qualities of a category that are stable and enduring, and thus provide insight into conceptual organization. To explore the role that linguistic input plays in children's production of generic nouns, we observed American and Chinese deaf children whose hearing losses prevented them from learning speech and whose hearing parents had not exposed them to sign. These children develop gesture systems that have language-like structure at many different levels. The specific question we addressed in this study was whether the gesture systems, developed without input from a conventional language model, would contain generics. We found that the deaf children used generics in the gestures they invented, and did so at about the same rate as hearing children growing up in the same cultures and learning English or Mandarin. Moreover, the deaf children produced more generics for animals than for artifacts, a bias found previously in adult English- and Mandarin-speakers and also found in both groups of hearing children in our current study. This bias has been hypothesized to reflect the different conceptual organizations underlying animal and artifact categories. Our results suggest that not only is a language model not necessary for young children to produce generic utterances, but the bias to produce more generics for animals than artifacts also does not require linguistic input to develop.  相似文献   
860.
Effects of the contingency for submission of homework assignments on the probability of assignment submission and on quiz grades were assessed in an undergraduate psychology course. Under an alternating treatments design, each student was assigned to a points condition for 5 of 10 quiz-related homework assignments corresponding to textbook chapters. Points were available for homework submission under this condition; points were not available under the no-points condition. The group-mean percentage of homework assignments submitted and quiz grades were higher for all chapters under the points condition than in the no-points condition. These findings, which were replicated in Experiment 2, demonstrate that homework submission was not maintained when the only consequences were instructor-provided feedback and expectation of improved quiz performance.  相似文献   
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