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991.
The movement-related cortical potential (MRCP) is a low-frequency negative shift in the electroencephalographic recording that occurs about 2 s before voluntary movement production. The MRCP is thought to reflect the cortical processes involved in movement planning and movement preparation. In recent years, researchers have used this potential to investigate the processes involved in motor skill learning. Their findings indicate differences in the amplitude and onset times of the MRCP between experienced and novice performers, which have been attributed to long-term training in the experts. The authors discuss these findings critically and consider their implications for both future research and practice.  相似文献   
992.
This study was a follow up investigation of Brawer et al.’s (Prof Psychol Res Pr 33(2):203–206, 2002) survey of education and training of clinical psychologists in religion/spirituality. Directors of clinical training were surveyed to determine whether changes had occurred in the coverage of religion and spirituality through course work, research, supervision, and in the systematic coverage of the content area. Results indicated an increased coverage in the areas of supervision, dedicated courses, inclusion as part of another course, and research. There was no increase in systematic coverage, but significantly more programs provided at least some coverage. The current study also assesses other areas of incorporation as well as directors’ opinions regarding the importance of religion/spirituality in the field of psychology.  相似文献   
993.
When the factor analysis model holds, component loadings are linear combinations of factor loadings, and vice versa. This interrelation permits us to define new optimization criteria and estimation methods for exploratory factor analysis. Although this article is primarily conceptual in nature, an illustrative example and a small simulation show the methodology to be promising.  相似文献   
994.
Previous studies on the impact of perceived threat on confirmatory information search (selective exposure) in the context of decision making have yielded mixed results. Some studies have suggested that confirmatory information search is reduced, yet others have found contradictory effects. The present series of 5 studies consistently found that the crucial moderator for these inconsistent findings was whether the induced threat was contextually related to the subsequent decision and information search tasks. Contextual incongruence (e.g., an induction of terrorist threat followed by an economic decision case) results in reduced levels of confirmatory information search, whereas a congruent threat (e.g., an induction of terrorist threat followed by a decision case on terrorism) results in increased levels of confirmatory information search. Analyses of the underlying psychological processes revealed that decision-unrelated threat inductions increase decision makers' experienced decision uncertainty, thus reducing confirmatory information search.  相似文献   
995.
The current study used latent profile analysis (LPA) to examine anger control in 257 second-grade children (∼8 years of age). Anger was induced through losing a game and prize to a confederate who cheated. Three components of anger control were assessed: self-report of awareness of anger, observed intensity of angry facial expressions, and skin conductance reactivity. These components served as indicators in an LPA conducted to determine whether distinct groups of children who differed in anger control profiles would emerge. Five groups were found: (a) Physiology-and-Expression Controllers (high self-report, low expression, low physiological arousal), (b) Expression-Only Controllers (high self-report, low expression, high physiological arousal), (c) Non-controllers (high self-report, high expression, medium physiological arousal), (d) Non-reactive (low self-report, low expression, low physiological arousal), and (e) Non-reporters (low self-report, medium expression, medium physiological arousal). These findings are discussed in terms of implications for the assessment of children’s anger control skills and intervention programs for children’s anger management.  相似文献   
996.
997.
Propensity score methods allow investigators to estimate causal treatment effects using observational or nonrandomized data. In this article we provide a practical illustration of the appropriate steps in conducting propensity score analyses. For illustrative purposes, we use a sample of current smokers who were discharged alive after being hospitalized with a diagnosis of acute myocardial infarction. The exposure of interest was receipt of smoking cessation counseling prior to hospital discharge and the outcome was mortality with 3 years of hospital discharge. We illustrate the following concepts: first, how to specify the propensity score model; second, how to match treated and untreated participants on the propensity score; third, how to compare the similarity of baseline characteristics between treated and untreated participants after stratifying on the propensity score, in a sample matched on the propensity score, or in a sample weighted by the inverse probability of treatment; fourth, how to estimate the effect of treatment on outcomes when using propensity score matching, stratification on the propensity score, inverse probability of treatment weighting using the propensity score, or covariate adjustment using the propensity score. Finally, we compare the results of the propensity score analyses with those obtained using conventional regression adjustment.  相似文献   
998.
Research on bystander intervention has produced a great number of studies showing that the presence of other people in a critical situation reduces the likelihood that an individual will help. As the last systematic review of bystander research was published in 1981 and was not a quantitative meta-analysis in the modern sense, the present meta-analysis updates the knowledge about the bystander effect and its potential moderators. The present work (a) integrates the bystander literature from the 1960s to 2010, (b) provides statistical tests of potential moderators, and (c) presents new theoretical and empirical perspectives on the novel finding of non-negative bystander effects in certain dangerous emergencies as well as situations where bystanders are a source of physical support for the potentially intervening individual. In a fixed effects model, data from over 7,700 participants and 105 independent effect sizes revealed an overall effect size of g = -0.35. The bystander effect was attenuated when situations were perceived as dangerous (compared with non-dangerous), perpetrators were present (compared with non-present), and the costs of intervention were physical (compared with non-physical). This pattern of findings is consistent with the arousal-cost-reward model, which proposes that dangerous emergencies are recognized faster and more clearly as real emergencies, thereby inducing higher levels of arousal and hence more helping. We also identified situations where bystanders provide welcome physical support for the potentially intervening individual and thus reduce the bystander effect, such as when the bystanders were exclusively male, when they were naive rather than passive confederates or only virtually present persons, and when the bystanders were not strangers.  相似文献   
999.
Noise is a pervasive and influential source of stress. Whether through the acute effects of impulse noise or the chronic influence of prolonged exposure, the challenge of noise confronts many who must accomplish vital performance duties in its presence. Although noise has diffuse effects, which are shared in common with many other chronic forms of stress, it also exerts its own specific influences on various forms of cognitive and motor response. We present a quantitative evaluation of these influences so that their harmful effects can be mitigated, their beneficial effects exploited, and any residual effects incorporated and synthesized into selection, training, and design strategies to facilitate human performance capacities. Predictions of single and joint moderator effects were made on the basis of major theories of noise and performance, specifically those explanations based on arousal, masking, or cognitive-resource mechanisms. These predictions were tested through moderator analyses of effects as a function of task type, performance measure, noise type and schedule, and the intensity and duration of exposure. Observed outcome effects (797 effect sizes derived from 242 studies) varied as a function of each of these moderators. Collective findings identified continuous versus intermittent noise, noise type, and type of task as the major distinguishing characteristics that moderated response. Mixed evidence was obtained for the traditional arousal and masking explanations for noise effects. The overall pattern of findings was most consistent with the maximal adaptability theory, a mental-resource-based explanation of stress and performance variation.  相似文献   
1000.
Defeat and entrapment are psychological constructs that have played a central role in evolutionary accounts of depression. These concepts have since been implicated in theoretical accounts of anxiety disorders and suicidality. The current article reports on a systematic review of the existing research investigating the links among defeat, entrapment, and psychopathology in the domains of depression, suicidality, posttraumatic stress disorder (PTSD), and other anxiety syndromes. Fifty-one original research articles were identified and critically reviewed. There was strong convergent evidence for a link with depressive symptoms, across a variety of clinical and nonclinical samples. Preliminary support for an association with suicidality was also observed, with effects not readily explainable in terms of comorbid depression. There was strong evidence for an association between defeat and PTSD, although this may have been partly accounted for by comorbid depression. The findings for other anxiety disorders were less consistent. There was, however, evidence that social anxiety in individuals with psychosis may be related to perceptions of entrapment. Overall, there was evidence that perceptions of defeat and entrapment were closely associated with various forms of human psychopathology. These effects were often in the moderate to large range and superseded the impact of other environmental and psychological stressors on psychopathology. We provide a unified theoretical model of how defeat and entrapment may contribute to these different psychopathological conditions. Clinical implications and avenues for future research are discussed.  相似文献   
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