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131.
Functional magnetic resonance imaging (fMRI) is used to study brain function during behavioral tasks. The participation of pediatric subjects is problematic because reliable task performance and control of head movement are simultaneously required. Differential reinforcement decreased head motion and improved vigilance task performance in 4 children (2 with behavioral disorders) undergoing simulated fMRI scans. Results show that behavior analysis techniques can improve child cooperation during fMRI procedures.  相似文献   
132.
Factor analysis is regularly used for analyzing survey data. Missing data, data with outliers and consequently nonnormal data are very common for data obtained through questionnaires. Based on covariance matrix estimates for such nonstandard samples, a unified approach for factor analysis is developed. By generalizing the approach of maximum likelihood under constraints, statistical properties of the estimates for factor loadings and error variances are obtained. A rescaled Bartlett-corrected statistic is proposed for evaluating the number of factors. Equivariance and invariance of parameter estimates and their standard errors for canonical, varimax, and normalized varimax rotations are discussed. Numerical results illustrate the sensitivity of classical methods and advantages of the proposed procedures.This project was supported by a University of North Texas Faculty Research Grant, Grant #R49/CCR610528 for Disease Control and Prevention from the National Center for Injury Prevention and Control, and Grant DA01070 from the National Institute on Drug Abuse. The results do not necessarily represent the official view of the funding agencies. The authors are grateful to three reviewers for suggestions that improved the presentation of this paper.  相似文献   
133.
We examine the hypothesis that the efficiency of executive control processes is less stable over time in older than younger adults. An age-related decrease in the efficiency of executive control should result in an increase in performance variability in task conditions requiring the recruitment of executive control processes and not in task conditions requiring minimal involvement of executive control. Performance variability was similar for younger and older adults in task conditions requiring minimal executive control and greater for older than younger adults in task conditions requiring executive control. These and other data are consistent with the proposal that aging is associated with a decrease in the stability of executive control over time.  相似文献   
134.
Davis  Deborah  Vernon  Michael L. 《Sex roles》2002,47(3-4):129-138
Use of cosmetic surgeries has increased steadily over the last decade, and continues to rise in young and old alike. The purpose of present research was to investigate the relationship of personality to use of cosmetic procedures of various kinds. It was expected that adult attachment style, in particular attachment anxiety, would be positively related to use of cosmetic procedures. Attachment anxiety involves excessive approval seeking and concern over achieving and maintaining the love of significant others (such as romantic relationship partners). Such concerns could, in turn, lead to use of a variety of strategies for maintaining positive regard, including cosmetic surgeries to enhance physical appearance. Results supported this hypothesis, particularly among women. Neuroticism was also related to some procedures, though the relationships were generally weaker than those for attachment anxiety, and largely disappeared in regression analyses that controlled for the separate influence of the two variables.  相似文献   
135.
This study investigated the effects of self-appraisal information, normative information, and task performance on performance appraisal ratings. Participants rated a fictitious subordinate's performance on a clerical task (which was either very good or moderately poor) subsequent to receiving self-assessment information (high or low) and normative information (present or absent). Self-appraisals affected performance ratings for poor performers but not for good performers, suggesting that judges are more motivated to please ratees than they are merely to adopt the subordinate's view of their own performance. Furthermore, objective normative information had greater influence than self-appraisals on performance ratings, suggesting that information source credibility has more influence than felt accountability on performance appraisals. Implications of the findings for organizations were discussed.  相似文献   
136.
This is a case study of a family with a child (age eight) with reactive attachment disorder and the subsequent individual and family therapy. Treatment of choice for the child was Eye Movement Desensitization and Reprocessing (EMDR) and supportive educational counseling for the parents and family. Qualitative evaluation of the process demonstrated that the parents observed an instant change in the child's attitude. The child reported that she felt better about family, school, and truthfulness, and stated about the therapy: It opened a window for me. A 12-month evaluation demonstrated continued positive effects.  相似文献   
137.
This study examined the effectiveness ofvisuo-motor behavior rehearsal(VMBR) as a method of reducing acute stress and improving police officer performance. Fifty-four recruits were randomly assigned to a treatment and a nontreatment condition prior to undergoing a highly stressful, critical event training scenario involving live fire. A manipulation check showed that participants who received VMBR displayed significantly lower scores on the cognitive state anxiety subscale of the Competitive State Anxiety Inventory-2; somatic state anxiety and self-confidence were unaffected by the VMBR treatment. Most importantly, participants in the VMBR training condition displayed better performance on the critical event scenario, including significantly more assailant hits. The findings are discussed with respect to the four-stage model of stress and human performance of Salas and colleagues.  相似文献   
138.
This paper outlines some of the special stresses that must be shouldered by clinicians—physicians, nurses, chaplains, social workers, pastoral staff, and others—whose work focuses on dying and extremely vulnerable patients. The utility of a theory of generative death anxiety as a framework for interpreting the nature of these special stresses is suggested. Three common burnout reactions are examined. The paper concludes that positive acceptance of personal mortality may help clinicians avoid burnout and lead to better therapeutic practice. This framework for interpreting therapeutic practice demonstrates the integral role spirituality plays in work with this particular patient group.  相似文献   
139.
While the intracarotid amobarbital procedure (IAP) was originally utilized to lateralize speech functions as an aid in the surgical treatment of epilepsy, additional uses for the IAP have emerged including: (1) the use of the IAP to predict post-surgical memory changes, including both global amnesia and smaller, yet significant, material-specific memory deficits; (2) the use of the IAP to provide confirmatory evidence of lateralization of seizure focus; and (3) the use of the IAP to predict post-surgical relief from seizures. While the literature on the IAP is extensive and growing, its utility is marred by the wide variability associated with the procedure itself from epilepsy center to center. This variability renders comparisons among IAP studies problematic and conclusions about IAP efficacy difficult. The variability associated with the amobarbital procedures, as well as the reliability and the validity of the IAP in its nonlanguage uses is reviewed here. A special emphasis is devoted to research conducted in the last decade. Also discussed is the future of the IAP including anticipated research directions.  相似文献   
140.
In the bioethical literature, discrimination in insurance on the basis of genetic risk factors detected by genetic testing has been defended and opposed on various ethical grounds. One important argument in favour of the practice is offered by those who believe that it is not possible to distinguish between genetic and non-genetic information, at least not for practical policy purposes such as insurance decision-making. According to the argument from indistinguishability, the use of genetic test information for insurance purposes should be permitted, because genetic test information is no different from non-genetic medical information in any relevant respect, therefore it would be inconsistent to prohibit the former whilst permitting the latter. This paper discusses and defends this argument and suggests a new, more tenable foundation.  相似文献   
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