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891.
892.
When procedural artifacts are controlled, it has been difficult to demonstrate directed forgetting in pigeons. However, previous research with pigeons has not allowed for the reallocation of working memory (from forget items to remember items) on forget-cued trials as is possible in human directed forgetting experiments. In the present experiment, directed forgetting was found while controlling for procedural artifacts and allowing the pigeons to reallocate memory resources on forget trials. The results indicate that under these conditions, pigeons have active control over memory processing. 相似文献
893.
John E. Carr G. Andrew H. Benjamin 《Journal of clinical psychology in medical settings》1997,4(2):143-153
Health care reform has put increasing pressure on faculty of medical schools to become self-supporting. Opportunities for clinical revenue will decrease, but psychologists who are able to generate research funding will become increasingly competitive, albeit as mercenaries, i.e., capable of paying their own way plus generating a profit to support departmental operations and educational programs. Changes in the health care system signal an end to psychiatry's paternalistic relationship to psychology and present opportunities for psychology proactively to influence its future role in health care. Research, political action, and revised scientific mission, models, and roles represent important strategies in the redefining of psychology as a basic science and major profession in health care. 相似文献
894.
895.
Although many researchers wishing to use the World-Wide Web for academic purposes rely on centralized Web services, they should be aware that it is neither expensive nor difficult to operate their own server. Doing so provides research-related benefits such as complete control over their host name and documents provided, the guaranteed ability to execute common gateway interface and server-side include programs, immediate access to their collected data, and the ability to better control who participates in their experiments. This paper surveys Web-server software features likely to be of interest to psychologists and conceptually summarizes their operation and use. The basic steps required to set up a Web server on popular microcomputers are reviewed, and security issues concerning Web-server operation are discussed. An accompanying resource Web page can assist users in setting up their own servers. 相似文献
896.
897.
Theoretical Medicine and Bioethics - 相似文献
898.
H Tristram Engelhardt 《Christian Bioethics: Non-Ecumenical Studies in Medical Morality》1997,3(1):3-19
Being a Christian involves metaphysical, epistemological, and social commitments that set Christians at variance with the dominant secular culture. Because Christianity is not syncretical, but proclaims the unique truth of its revelations, Christians will inevitably be placed in some degree of conflict with secular health care institutions. Because being Christian involves a life of holiness, not merely living justly or morally, Christians will also be in conflict with the ethos of many contemporary Christian health care institutions which have abandoned a commitment to Christian spirituality. In this regard, managed care raises the special question of how Christian institutions can act morally under financial constraints and maintain their character while under the control of secular managers. This question itself raises the further question as to why health care institutions need even pose this query when there are Christian physicians and nurses who could work for less, or Christian men and women who could become sisters and brothers and work for nothing. Contemporary challenges to Christians to maintain their integrity in a post-Christian world have much of their force because Christians have failed to maintain traditional Christian sprituality. In the face of that failure, Christian physicans and nurses will find themselves in greater conflict with health care institutions, because few will any longer understand the requirements of traditional Christianity. In its place, they will have put a generic spirituality, a value-neutral understanding of the role of the health professional, and an anonymous commitment to social justice. 相似文献
899.
In this paper, we examine whether color and shape, tied to a single object in space, (1) are identified and selected in series or in parallel, (2) are identified and selected in a dependent, self-terminating manner or in an independent and exhaustive manner, and (3) are conjoined by a feature integration process before or only after an initial stage of separate attribute analyses has finished. We measured response time and the selection negativity (SN) derived from event-related brain potentials when participants responded to a unique conjunction of color and shape in a go/no-go target detection task. The discriminability of the color and the shape of the conjunction was manipulated in three conditions. When color and shape were easy to discriminate, the SNs to color and shape started at the same time. When one attribute was less discriminable, the SN to that attribute started later, but not the SN to the complementary attribute. This suggests that color and shape are identified and selected in parallel. In all three discriminability conditions, the SNs to color and shape were initially independent but later interacted. This suggests that color and shape are initially selected independently and exhaustively, after which their conjunction is analyzed. The SN to local shape features started later than that to the conjunction of color and global shape features, which suggests that feature integration can start before the analyses of the separate attributes have finished. 相似文献
900.
Joan M Sinnott Charles H. Brown Waseem T. Malik Regina A. Kressley 《Attention, perception & psychophysics》1997,59(8):1214-1224
Multidimensional scaling (MDS) was used to compare perceptual maps for 10 synthetic English vowels in humans and Old World monkeys (Macaca fuscata andCercopithecus albogularis). Subjects discriminated among the vowels using a repeating background procedure, and reaction times were submitted to an MDS analysis to derive measures of perceived similarity. The dimensions that emerged related to the frequencies of the first(F1), second(F2), and third(F3) formants. Human data indicated a good match to previous MDS studies using rating procedures or confusion matrices: The dominant dimension mapped onto vowelF2, the phonetically most important formant, and the second and third dimensions mapped ontoF1 andF3, respectively.For monkeys, equal weightings occurred forF1 andF2, andF3 was not clearly represented. Monkey sensitivity to the formants appeared to relate to formant amplitudes. If monkeys are giving an accurate representation of the psychoacoustic relations among the formants, then our human results suggest that species-specific mechanisms, reflecting the salience of the phonetic feature of advancement, may contribute to vowel coding in humans. 相似文献