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91.
Humans subjects research entails significant legal and ethical obligations. Neuroimaging researchers must be familiar with the requirements of human subjects protection, including evolving standards for the protection of privacy and the disclosure of risk in "non-therapeutic" research. Techniques for creating veridical surface renderings from volumetric anatomical imaging data raise new privacy concerns, particularly under the federal medical privacy regulation. Additionally, neuroimaging researchers must consider their obligation to communicate research results responsibly. The emerging field of neuroethics should strive to raise awareness of these issues and to involve neuroimaging researchers in the legal, ethical, and policy debates that currently surround human subjects research.  相似文献   
92.
Daniel Callahan's concept of a sustainable medicine is examined by looking at experiences Old Order Amish communities have had with organ and bone marrow transplantation. The Amish possess many characteristics that might make them embrace limits on the use of expensive, life-prolonging medical treatments: they believe that the good of the individual should be subordinated to the good of the community, they are suspicious of progress as a goal, and they are more comfortable with dying than many other modern Americans. However, the Amish actively pursue these treatments without the benefit of private or government insurance. Although the Amish affective response to sick individuals is worthy of emulating, their commitment to help individuals obtain and pay for transplants has had negative financial and cultural effects on some Amish communities. The Amish experience can thus teach us lessons about how to care for one another when we are sick and dying, but it can also teach us how difficult but important it is to limit some forms of expensive care for the good of our communities.  相似文献   
93.
Cross-correlation and most other longitudinal analyses assume that the association between 2 variables is stationary. Thus, a sample of occasions of measurement is expected to be representative of the association between variables regardless of the time of onset or number of occasions in the sample. The authors propose a method to analyze the association between 2 variables when the assumption of stationarity may not be warranted. The method results in estimates of both the strength of peak association and the time lag when the peak association occurred for a range of starting values of elapsed time from the beginning of an experiment.  相似文献   
94.
Deferred imitation of object-related actions and generalization of imitation to similar but not identical tasks was assessed in three human-reared (enculturated) chimpanzees, ranging in age from 5 to 9 years. Each ape displayed high levels of deferred imitation and only slightly lower levels of generalization of imitation. The youngest two chimpanzees were more apt to generalize the model's actions when they had displayed portions of the target behaviors at baseline, consistent with the idea that learning is more likely to occur when working within the "zone of proximal development." We argue that generalization of imitation is the best evidence to date of imitative learning in chimpanzees. Electronic Publication  相似文献   
95.
Cross-sociocultural group measurement equivalency is an important issue that generally has not been studied in the coping literature. Measurement equivalency of the COPE (Carver, Scheier, & Weintraub, 1989) was assessed across two sociocultural groups, a sample of 100 Anglo middle-class divorced mothers and a sample of 122 low-income Mexican American/Mexican immigrant mothers. A series of restrictive confirmatory factor analyses revealed that seven of the COPE's subscales may be measuring the same underlying construct across populations. However, scores derived from the subscales may not represent the same magnitude of the construct in these two groups. This study makes an important first step in furthering the understanding of coping strategies in low-income Mexican American/Mexican immigrant mothers. This study also illustrates the importance of testing for measurement equivalency before conducting comparative research in disparate populations.  相似文献   
96.
The effect of sentence priming on picture naming was investigated across the lifespan, from age 3 to 87 years. Names that are normally acquired before 3 years of age were presented in auditory contexts that were semantically congruent, incongruent, or neutral in relation to each picture and its name. Sentential priming was present at all age levels. Facilitation (neutral vs. congruent) was significantly by 4 years of age and did not vary significantly with age. Interference (incongruent vs. neutral) was significant at all age levels, but changed nonmonotonically with age (largest in the youngest children, stable from young adulthood through age 70, with a small increase in the oldest participants). We conclude that picture naming is a useful tool for the investigation of sentential priming effects across the lifespan and that it can reveal potentially interesting developmental changes in the effects of sentential context on word retrieval.  相似文献   
97.
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   
98.
Confidence and accuracy, while often considered to tap the same memory representation, are often found to be only weakly correlated (e.g., Bothwell, Deffenbacher, & Brigham, 1987; Deffenbacher, 1980). There are at least two possible (nonexclusive) reasons for this weak relation. First, it may be simply due to noise of one sort or another; that is, it may come about because of both within- and between-subjects statistical variations that are partially uncorrelated for confidence measures on the one hand and accuracy measures on the other. Second, confidence and accuracy may be uncorrelated because they are based, at least in part, on different memory representations that are affected in different ways by different independent variables. We propose a general theory that is designed to encompass both of these possibilities and, within the context of this theory, we evaluate effects of four variables—degree of rehearsal, study duration, study luminance, and test luminance—in three face recognition experiments. In conjunction with our theory, the results allow us to begin to identify the circumstances under which confidence and accuracy are based on the same versus different sources of information in memory. The results demonstrate the conditions under which subjects are quite poor at monitoring their memory performance, and are used to extend cue utilization theories to the domain of face recognition.  相似文献   
99.
This study examined the psychometric properties of the Revised Child Anxiety and Depression Scale (RCADS) in a clinical sample of 513 youth referred for mental health assessment at a university clinic. Internal consistency and factor analysis provided support for the factorial validity of the RCADS. Convergent and discriminant validity tests against both clinical interview and self-report criteria also suggested favorable properties of the RCADS. In comparative tests with traditional measures of anxiety and depression, the RCADS generally showed greater correspondence to specific diagnostic syndromes. Clinical cutoffs are reported for the purposes of future clinical and research applications.  相似文献   
100.
When nonstigmatized individuals enact certain role-violating behaviors, they risk becoming "falsely accused deviants" (H. S. Becker, 1963, p. 20). For instance, when heterosexual men perform stereotypically feminine behaviors, they are liable to get misclassified as homosexual. Findings presented here reveal that expectations of identity misclassification fuel nonstigmatized individuals' negative reactions to role violations (Studies 1-2) and that using a disclaimer--that is, informing their audience of their nonstigmatized identity--assuages people's discomfort during a role-violating behavior (Studies 3-4). Moreover, when not concerned about being misclassified, nonstigmatized individuals benefit psychologically from the enactment of a challenging role violation (Study 4). Discussion considers the nature of the threat that misclassified role violators face and compares the plight of the falsely accused deviant to that of the truly stigmatized individual.  相似文献   
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