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151.
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   
152.
In the first part of this paper we review evidence suggesting that there exists a mechanism that selects input on the basis of its similarity to the required action. This response-based input selection differs from the more established space- and object-based input selection in that it is not constrained by the structure of the input. Our evidence suggests that the two-choice Stroop effect is caused by this response-based selection mechanism. By contrast, it is known that the flanker effect is determined by the space- and object- based selection mechanisms. We explore whether the conflict resolution of the Stroop and flanker tasks is different as well by embedding these two tasks in a PRP (Psychological Refractory Period) paradigm. We show that the Stroop and the PRP effects are additive whereas the flanker and the PRP effects are underadditive, suggesting that the processes in charge of the conflict resolution in the Stroop and the flanker tasks are indeed different. We discuss possible reasons for this difference, and discuss possible ways in which the response-based mechanism can be implemented in information processing models.  相似文献   
153.
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   
154.
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   
155.
Numerous previous investigators have explained species differences in spatial memory performance in terms of differences in foraging ecology. In three experiments we attempted to extend these findings by examining the extent to which the spatial memory performance of echidnas (or "spiny anteaters") can be understood in terms of the spatio-temporal distribution of their prey (ants and termites). This is a species and a foraging situation that have not been examined in this way before. Echidnas were better able to learn to avoid a previously rewarding location (to "win-shift") than to learn to return to a previously rewarding location (to "win-stay"), at short retention intervals, but were unable to learn either of these strategies at retention intervals of 90 min. The short retention interval results support the ecological hypothesis, but the long retention interval results do not. Electronic Publication  相似文献   
156.
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   
157.
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   
158.
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   
159.
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   
160.
Archer RP  Newsom CR 《Assessment》2000,7(3):227-235
In 1991, Archer, Maruish, Imhof, and Piotrowski presented survey findings based on the responses of a national sample of psychologists who performed psychological assessment with adolescent clients. The current survey was designed to update their results by examining the test use practices reported by 346 psychologists who work with adolescents in a variety of clinical and academic settings. These respondents represented an adjusted survey return rate of 36% and predominantly consisted of doctoral prepared psychologists (95%) in private practice settings (51%). The survey respondents had a mean of 13.6 years of post-degree clinical experience, and spent an average of 45% of their clinical time working with adolescents. Survey results reveal a substantial similarity in test usage between the 1991 survey and the current investigation. For example, the Wechsler Intelligence Scales, Rorschach, Thematic Apperception Test (TAT), and Minnesota Multiphasic Personality Inventory (MMPI) remain among the widely used tests with adolescents. However, several changes were also noted including a reduction in the use of the Bender-Gestalt and increases in the use of parent and teacher rating instruments. The current findings are used to estimate the relative popularity of an extensive list of test instruments, compare current findings to 1991 survey results, and to examine several issues related to general effects of managed care procedures and policies on test usage with adolescents.  相似文献   
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