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991.
McIntyre A 《Theoretical medicine and bioethics》2004,25(1):61-74
The U.S. Supreme Court's majorityopinion in Vacco v. Quill assumes thatthe principle of double effect explains thepermissibility of hastening death in thecontext of ordinary palliative care and inextraordinary cases in which painkilling drugshave failed to relieve especially intractablesuffering and terminal sedation has beenadopted as a last resort. The traditionaldoctrine of double effect, understood asproviding a prohibition on instrumental harmingas opposed to incidental harming or harming asa side effect, must be distinguished from otherways in which the claim that a result is notintended might be offered as part of ajustification for it. Although double effectmight appropriately be invoked as a constrainton ordinary palliative care, it is not clearthat it can be coherently extended to justifysuch practices as terminal sedation. A betterapproach would reconsider double effect'straditional prohibition on hastening death as ameans to relieve suffering in the context ofacute palliative care. 相似文献
992.
Children who experienced a highly stressful natural disaster, Hurricane Andrew, were interviewed within a few months of the event, when they were 3-4 years old, and again 6 years later, when they were 9-10 years old. Children were grouped into low, moderate, or high stress groups depending on the severity of the experienced storm. All children were able to recall this event in vivid detail 6 years later. In fact, children reported over twice as many propositions at the second interview as at the first. At the initial interview, children in the high stress group reported less information than children in the moderate stress group, but 6 years later, children in all three stress groups reported similar amounts of information. However children in the high stress group needed more questions and prompts than children in the other stress groups. Yet children in the high stress group also reported more consistent information between the two interviews, especially about the storm, than children in the other stress groups. Implications for children's developing memory of stressful events are discussed. 相似文献
993.
This study shows that the classical phonological similarity effect (PSE) in immediate serial recall is critically affected by the lexicality of list items, the type of phonological similarity involved, and the scoring procedure. PSE was present in the serial recall score when phonologically distinct words were compared to words that share the middle vowel and end consonant (rhyming lists). PSE was absent in the serial recall score when phonologically distinct words were compared to words that share the initial and final consonants (consonant frame lists). There was a reversal of PSE in serial recall of nonwords when comparing distinct lists to both types of similar lists. Recall accuracy on the other hand was higher for distinct lists regardless of lexicality. Item errors dominated in relation to order errors in the case of nonwords, whereas order errors dominated in relation to item errors in the case of words. Furthermore, order errors were more common for phonologically similar lists, whereas item errors were more common for phonologically distinct lists. This may be the result of intra-list and inter-list interference, respectively. The dominance of the former error type may cause a classical PSE, whereas the dominance of the latter error type may cause a reversal of PSE. Finally, an item identification task yielded no evidence of an association between intra-list interference and discriminability of items in a list. 相似文献
994.
Transfer-appropriate processing theory (Roediger, Weldon, & Challis, 1989) proposes that dissociations between performance on explicit and implicit memory tests arise because these tests often rely on different types of information processing (e.g., perceptual processing vs conceptual processing). This perspective predicts that implicit and explicit memory tasks that rely primarily on conceptual processing should show comparable results, not dissociations. Numerous studies have demonstrated such similarities. It is, however, possible that these results arise from explicit memory contamination of performance on implicit memory tasks. To address this issue, an experiment was conducted in which participants were administered the sedative midazolam prior to study. Midazolam is known to create a temporary, but dense, period of anterograde amnesia. The effects of blocking stimulus materials by semantic category at study and generation at study were investigated on category exemplar production and category-cued recall. The results of this study demonstrated a dissociation of the effects of midazolam on category exemplar production and category-cued recall. Specifically, midazolam reduced the effect of blocking stimulus materials in category-cued recall, but not in category exemplar production. The differential effect of midazolam on explicit and implicit memory is at odds with transfer-appropriate processing theory and suggests that theories of memory must distinguish the roles of different types of conceptual processing on implicit and explicit memory tests. 相似文献
995.
Abstract— P.M. is a synesthete who experiences colors when viewing alphanumeric symbols. Her search for a target differing from distractors by a synesthetic color feature takes the form of a pop-out search. Thus, it would seem that synesthesia can occur preattentively. However, discrepancies between the regression functions of response times observed in target-present trials and target-absent trials, and the fact that fast response times occur only when the target is within a few degrees of visual angle from fixation, indicate that P.M.'s synesthesia does not occur preattentively, but rather is within the focus of attention. We conclude that synesthesia is a genuine perceptual phenomenon that can have substantial influence on visual processing. 相似文献
996.
Abstract— Whereas most previous findings suggest that memory may become more abstract over time, so that memory for gist outlasts verbatim memory, there are findings suggesting that abstract information may sometimes be instantiated in more specific terms. In this study, we examined the hypothesis that retained information tends to converge at an intermediate level of abstractness—the basic level. In two experiments, we found bidirectional, symmetrical shifts in the memory for story material: Participants presented with either subordinate terms (e.g., sports car) or superordinate terms (e.g., vehicle) tended to falsely report basic-level terms (e.g., car) instead. This pattern emerged for both recall and recognition memory tests, at both immediate and delayed testing, and under free and forced reporting. The results suggest that the basic level, which has been considered cognitively optimal for perception, categorization, and communication, is also the preferred level for retaining episodic information in memory. 相似文献
997.
The influence of sex versus sex-related traits on long-term memory for gist and detail from an emotional story 总被引:2,自引:0,他引:2
Recent findings demonstrate sex-related differences in the neurobiological mechanisms by which emotional arousal influences memory, and raise questions about the extent to which memory for emotional events may differ between males and females. Here we examine whether sex-related differences exist in the recall of central (gist) information and peripheral detail from an emotional story. Healthy subjects viewed a brief, narrated slide-show containing emotional elements in its middle section. One week later, they received an incidental multiple-choice recognition test for the story. Following the test, each subject completed the BEM Sex-Role Inventory, an assessment of sex-related masculine and feminine traits. The results reveal no differences in recall of either central or peripheral story information when considering the performance of actual men and women, but a significant difference when considering male and females as determined by their BEM test scores. "BEM" males (subjects with net male BEM scores) showed significantly enhanced recall of central emotional information. "BEM" females did not. Both groups showed significantly enhanced recall of peripheral emotional information, although this effect appeared larger in BEM females than in BEM males. The influences of "BEM" sex and type of information (central, peripheral) significantly interacted to influence emotional memory performance. These findings confirm the existence of sex-related influences in the recall of emotional information, and suggest that sex-related traits, rather than actual sex per se, may be a more sensitive indicator of these influences. 相似文献
998.
As people study more facts about a concept, it takes longer to retrieve a particular fact about that concept. This fan effect
(Anderson, 1974) has been attributed to competition among associations to a concept. Alternatively, the mental-model theory
(Radvansky & Zacks, 1991) suggests that the fan effect disappears when the related concepts are organized into a single mental
model. In the present study, attentional focus was manipulated to affect the mental model to be constructed. One group of
participants focused on the person dimension of personlocation pairs, whereas the other group focused on the location dimension.
The result showed that the fan effect with the focused dimension was greater than the fan effect with the nonfocused dimension,
which is contrary to the mental-model theory. The number of associations with a concept is indeed crucial during retrieval,
and the importance of the information seems to be accentuated with attentional focus. 相似文献
999.
This article examines the theoretical basis of decision-making deficits exhibited by cocaine abusers in a laboratory decision-making
task first described by Bechara, Damasio, Damasio, and Anderson (1994). A total of 12 male cocaine abusers and 14 comparison
subjects performed the task, and the cocaine group performed significantly worse than the comparison group. A cognitive modeling
analysis (Busemeyer & Stout, 2002) was used to estimate three parameters that measure importance of the cognitive, motivational,
and response processes for determining the observed performance deficit. The results of this analysis indicated, for the first
time, that motivational and choice consistency factors, but not learning/ memory were mainly responsible for the decision-making
deficit of the cocaine abusers in this task. 相似文献
1000.
Family Environments of Women Seeking BRCA1/BRCA2 Genetic Mutation Testing: An Exploratory Analysis 总被引:1,自引:0,他引:1
Keenan LA Lesniak KT Guarnaccia CA Althaus B Ethington G Blum JL 《Journal of genetic counseling》2004,13(2):157-176
Although there is some understanding of the shared characteristics and predictors of psychological distress of women participating in hereditary breast and ovarian cancer registries, these same characteristics are only beginning to be identified in research on community women seeking genetic testing for BRCA1/BRCA2 gene mutations. This study provides an initial exploration of characteristics associated with family environments for 51 community women waiting to receive such genetic testing results. Thirty-four of the 36 women classified on family environment type of the Family Environment Scale (FES) were from Personal Growth-Oriented families. Comparisons of women with and without personal cancer histories resulted in a trend for women with personal cancer histories to be classified as from Independence-Oriented families. Reported distress appears to vary for different family emphases based on family and personal cancer history. A moral-religious family emphasis consistently appeared to be associated with decreased psychological distress. Preliminary analyses comparing these community women (who were not part of a hereditary registry but were self- or physician-referred) seeking genetic testing with normal and distressed family means found that increased cohesion and expressiveness may be related to decreased conflict, indicative of potentially supportive family environments for these women. When compared with normative data, a subset consisting of the Ashkenazi Jewish women showed a trend of less cohesion than normal families, but similar cohesion levels as distressed families. 相似文献