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931.
Form A of the Dysfunctional Attitude Scale (DAS-A), a self-report measure of depressive beliefs, is widely used to test Beck's cognitive model of depression. The present study is the first to evaluate the DAS-A factor structure in an adolescent population of 542 high school juniors and the first to examine a hierarchical model. Findings support the existence of a hierarchical structure consisting of two conceptually meaningful group factors (Dysfunctional Attitudes About Achievement and Dysfunctional Attitudes About Needing Approval), a method factor consisting of reverse-worded items, and a general factor, which accounts for 65% of the variance in total scores. The general factor is related to sociotropy, autonomy, and neuroticism, whereas the Dysfunctional Attitudes About Achievement and Dysfunctional Attitudes About Needing Approval factors demonstrate convergent and discriminant validity with respect to autonomy and sociotropy. The structure displays partial metric invariance in female and male students as well as in Caucasian and Non-Caucasian students. 相似文献
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933.
Working memory plays a crucial role in supporting learning, with poor progress in reading and mathematics characterizing children with low memory skills. This study investigated whether these problems can be overcome by a training program designed to boost working memory. Children with low working memory skills were assessed on measures of working memory, IQ and academic attainment before and after training on either adaptive or non‐adaptive versions of the program. Adaptive training that taxed working memory to its limits was associated with substantial and sustained gains in working memory, with age‐appropriate levels achieved by the majority of children. Mathematical ability also improved significantly 6 months following adaptive training. These findings indicate that common impairments in working memory and associated learning difficulties may be overcome with this behavioral treatment. 相似文献
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936.
The study examined whether face‐specific perceptual brain mechanisms in 9‐month‐old infants are differentially sensitive to changes in individual facial features (eyes versus mouth) and whether sensitivity to such changes is related to infants' social and communicative skills. Infants viewed photographs of a smiling unfamiliar female face. On 30% of the trials, either the eyes or the mouth of that face were replaced by corresponding parts from a different female. Visual event‐related potentials were recorded to examine face‐sensitive brain responses. Results revealed that increased competence in expressive communication and interpersonal relationships was associated with a more mature response to faces, as reflected in a larger occipito‐temporal N290 with shorter latency. Both eye‐ and mouth changes were detected, though infants derived different information from these features. Eye changes had a greater impact on the face perception mechanisms and were not correlated with social or communication development, whereas mouth changes had a minimal impact on face processing but were associated with levels of language and communication understanding. Copyright © 2009 John Wiley & Sons, Ltd. 相似文献
937.
John M. Ferron Bethany A. Bell Melinda R. Hess Gianna Rendina-Gobioff Susan T. Hibbard 《Behavior research methods》2009,41(2):372-384
Multiple-baseline studies are prevalent in behavioral research, but questions remain about how to best analyze the resulting
data. Monte Carlo methods were used to examine the utility of multilevel models for multiplebaseline data under conditions
that varied in the number of participants, number of repeated observations per participant, variance in baseline levels, variance
in treatment effects, and amount of autocorrelation in the Level 1 errors. Interval estimates of the average treatment effect
were examined for two specifications of the Level 1 error structure (σ2
I and first-order autoregressive) and for five different methods of estimating the degrees of freedom (containment, residual,
between—within, Satterthwaite, and Kenward—Roger). When the Satterthwaite or Kenward—Roger method was used and an autoregressive
Level 1 error structure was specified, the interval estimates of the average treatment effect were relatively accurate. Conversely,
the interval estimates of the treatment effect variance were inaccurate, and the corresponding point estimates were biased. 相似文献
938.
United States federal regulations for pediatric research with no prospect of direct benefit restrict institutional review board (IRB) approval to procedures presenting: 1) no more than "minimal risk" ( section sign 45CFR46.404); or 2) no more than a "minor increase over minimal risk" if the research is commensurate with the subjects' previous or expected experiences and intended to gain vitally important information about the child's disorder or condition ( section sign 45CFR46.406) (DHHS 2001). During the 25 years since their adoption, these regulations have helped IRBs balance subject protections with the pursuit of scientific knowledge to advance children's welfare. At the same time, inconsistency in IRB application of these regulations to pediatric protocols has been widespread, in part because of the ambiguity of the regulatory language. During the past decade, three federally-charged committees have addressed these ambiguities: 1) the National Human Research Protections Advisory Committee (NHRPAC) (Washington, DC), 2) the Institute of Medicine (IOM) Committee on the Ethical Conduct of Clinical Research Involving Children (Washington, DC); and 3) the United States Department of Health and Human Services Secretary's Advisory Committee for Human Research Protections (SACHRP) (Washington, DC). The committees have reached similar conclusions on interpretation of language within regulations section sign section sign 45CFR46.404 and 406; these conclusions are remarkably consistent with recent international recommendations and those of the original National Commission for the Protection of Human Subjects of Biomedical and Behavioral Research (1977) report from which current regulations are based. Drawing on the committees' public reports, this article identifies the ethical issues posed by ambiguities in regulatory language, summarizes the committees' deliberations, and calls for a national consensus on recommended criteria. 相似文献
939.
The study of spatial frequency is being used increasingly often to investigate processes underlying visual word recognition. However, research in this area has adopted techniques that require the physical deformation of word targets used in experiments (e.g., filtered images of words, words embedded in visual noise), and this approach may limit the inferences that can be made about the role of spatial frequencies in normal word recognition. Spatial frequency adaptation is described in this article as an additional technique for studying the role of spatial frequency information in word recognition. The advantage of this technique is that it alters participants' sensitivity to particular spatial frequencies and so allows the study of spatial frequency involvement in word recognition using normal images of word stimuli. The application of the adaptation technique to studies of word recognition is explained in detail and its potential is then demonstrated by an example word recognition experiment in which spatial frequency adaptation was used. 相似文献
940.
Harris LT McClure SM van den Bos W Cohen JD Fiske ST 《Cognitive, affective & behavioral neuroscience》2007,7(4):309-316
The medial prefrontal cortex (MPFC) reliably activates in social cognition and reward tasks. This study locates distinct areas
for each. Participants made evaluative (positive/negative) or social (person/not a person) judgments of pictured positive
or negative people and objects in a slow event-related design. Activity in an anterior rostral region (arMPFC) was significantly
greater for positive than for negative persons but did not show a valence effect for objects, and this was true regardless
of the judgment task. This suggests that the arMPFC is tuned to social valence. Interestingly, however, no regions of the
MPFC were found to be responsive to social information independently of valence. A region-of-interest analysis of the paraanterior
cingulate cortex (pACC), previously implicated in reward processing, demonstrated sensitivity to the valence of all stimuli,
whether persons or objects, across tasks. Affective evaluation may be a general function of the MPFC, with some regions being
tuned to more specific domains of information (e.g., social) than are others. 相似文献