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231.
One hundred thirty-five psychiatric inpatients admitted for suicidal danger were surveyed regarding their views on the benefits/limitations of written no-suicide agreements. A survey instrument developed for this study revealed that these inpatients, for the most part, rated written no-suicide agreements in a positive manner and in ways consistent with clinical opinion expressed in a number of qualitative/expert-opinion articles. Positive views of no-suicide agreements were not materially influenced by social desirability or age, nor were they moderated by gender, presence/absence of Axis II disorders, or admission suicidal danger. However, patient suicide attempt history (no attempts, one attempt, or more than one attempt) exerted a moderating effect on patients' ratings of the helpfulness of these contracts. Multiple attempters viewed written no-suicide agreements as less helpful than those patients with a single or no prior attempts. The methodological problems and generalizability concerns associated with these results are discussed and future research needs are suggested. 相似文献
232.
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234.
Brown AS 《Psychonomic bulletin & review》2002,9(3):403-425
Recent research on the cognitive dysfunctions experienced by human anmesic patients indicates that very long term (multidecade) changes may occur in memory.Flat retrograde amnesia (RA), consisting of a uniform memory deficit for information from all preamnesia time periods, indicates a simple, monolithic retrieval problem, whereasgraded RA, with greater memory deficits for information from recent as opposed to remote time periods, suggests the presence of a gradual long-term encoding, or consolidation, process. An evaluation of 247 outcomes from 61 articles provides strong evidence of graded RA across different cerebral injuries, materials, and test procedures, as well as in measures of both absolute and relative (patient vs. control) performance. Future conceptualizations of human memory should address the possibility that memories increase in resistance to forgetting, or reduction in trace fragility, across many decades. 相似文献
235.
To examine the role of perceptual object representations in the control of eye movements and attention, a pair of experiments adapted the object-cuing paradigm of Egly, Driver, and Rafal (1994) to require eye movements. Displays were pairs of adjacent rectangles, each containing two characters. Observers were asked to make a speeded judgment of a target character’s orientation, and a cue was provided prior to target/distractor onset to indicate the target’s likely location. Gaze-contingent presentation of target and distractors was used to demand overt scanning of displays. Eye movements during task performance evinced two forms of object-based effects. First, saccades following fixation on an invalidly cued item were more likely to be made within the cued rectangle than between rectangles. Second, saccades within the cued rectangle were preceded by shorter dwell times than saccades between rectangles. Extrafoveal processing of stimuli within the cued rectangle, however, was not facilitated, suggesting that covert attention was not allocated more densely within the cued than within the uncued object. 相似文献
236.
Two functionally distinct forms of recognition memory have been identified in human and nonhuman species—the ability to recollect qualitative information about previous events, and the ability to differentiate between familiar and novel stimuli. Separate dual-process theories have been developed in the animal and human literatures to account for these findings. However, it is not clear whether these theories describe the same two underlying memory processes. On the basis of animal studies of medial temporal lobe function, familiarity is expected to exhibit disproportionately fast forgetting compared with recollection over short retention intervals. We tested this prediction in healthy human subjects by examining recognition forgetting rates across a range of 8–32 intervening items and found significant forgetting in the accuracy of familiarity-based discriminations and no evidence of forgetting in the accuracy of recollection-based discriminations. In agreement with the results from nonhuman species, the present results indicate that item familiarity decreases more rapidly than recollection over short retention intervals. 相似文献
237.
The ALCOVE model of category learning, despite its considerable success in accounting for human performance across a wide
range of empirical tasks, is limited by its reliance on spatial stimulus representations. Some stimulus domains are better
suited to featural representation, characterizing stimuli in terms of the presence or absence of discrete features, rather
than as points in a multidimensional space. We report on empirical data measuring human categorization performance across
a featural stimulus domain and show that ALCOVE is unable to capture fundamental qualitative aspects of this performance.
In response, a featural version of the ALCOVE model is developed, replacing the spatial stimulus representations that are
usually generated by multidimensional scaling with featural representations generated by additive clustering. We demonstrate
that this featural version of ALCOVE is able to capture human performance where the spatial model failed, explaining the difference
in terms of the contrasting representational assumptions made by the two approaches. Finally, we discuss ways in which the
ALCOVE categorization model might be extended further to use “hybrid” representational structures combining spatial and featural
components. 相似文献
238.
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
239.
Nersesyan AK 《Science and engineering ethics》2002,8(3):291-293
The author describes problems facing Armenia in reorganization of the structure of science in the post-socialist era with
the aim of utilizing limited state resources more efficiently by reducing the number of separate scientific institutes, concentrating
on essential core subjects required by the nation and encouraging all other projects to compete in the international arena
for grant sponsorship.
An earlier version of this paper was presented at an International Conference on “Conflict of Interest and its Significance
in Science and Medicine” held in Warsaw, Poland on 5–6 April, 2002. 相似文献
240.
Xenotransplantation, or the use of animal cells, tissues and organs for humans, has been promoted as an important solution
to the worldwide shortage of organs. While scientific studies continue to be done to address problems of rejection and the
possibility of animal-to-human virus transfer, socio-ethical and legal questions have also been raised around informed consent,
life-long monitoring, animal welfare and animal rights, and appropriate regulatory practices. Many calls have also been made
to consult publics before policy decisions are made. This paper describes the Canadian public consultation process on xenotransplantation
carried out by the Canadian Public Health Association in an arm’s length process from Health Canada, the ministry overseeing
government health policy and regulation. Focusing on six citizen fora conducted around the country patterned after the citizen
jury deliberative approach, the paper describes the citizen panelists’ recommendations to hold off on proceeding with clinical
trials and the rationales behind this recommendation. The consultation process is discussed in the context of constructive
technology assessment, a framework which argues for broader input into earlier stages of technology innovation, particularly
at the technology design stage.
This study was supported by a grant to the first author from the Social Sciences and Humanities Research Council in Canada. 相似文献