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871.
Event-related potentials were used to study how parsing of German relative clauses is influenced by semantic information. Subjects read well-formed sentences containing either a subject or an object relative clause and answered questions concerning the thematic roles expressed in those sentences. Half of the sentences contained past participles that on grounds of semantic plausibility biased either a subject or an object relative reading; the other half contained past participles that provided no semantic information favoring either reading. The past participle elicited an N400 component, larger in amplitude for neutral than for semantically biased verbs, but this occurred only in the case of subject relative clauses. More specific effects were obtained only for a subgroup of subjects, when these were grouped into fast and slow comprehenders on the basis of their questionanswering reaction times. Fast comprehenders showed larger N400 amplitudes for neutral than for semantically biased past participles in general and larger N400s for the latter when there was a bias for an object relative reading as opposed to a subject relative reading. Syntactic ambiguity resolution, indicated by an auxiliary in sentence final position, was associated in this subgroup with a positive component (P345), larger in amplitude for auxiliaries indicating an object relative reading than for those indicating a subject relative reading. The latter component was independent of semantically biasing information given by a preceding past participle. Implications of these findings for models of language comprehension are considered. 相似文献
872.
John D. Teasdale Barbara H. Dritschel Melanie J. Taylor Linda Proctor Charlotte A. Lloyd Ian Nimmo-Smith Alan D. Baddeley 《Memory & cognition》1995,23(5):551-559
Stimulus-independent thoughts (SITs) are streams of thoughts and images unrelated to immediate sensory input. Four experiments examined the contribution of aspects of working memory to production of SITs. In Experiments 1 and 2, interventions that were targeted on, respectively, phonological and visuospatial components of working memory both interfered with production of SITs, but there was evidence that these tasks also made demands on central executive resources. Experiments 3 and 4 specifically examined the hypothesis that production of SITs and control of nonproceduralized tasks both depend on central executive resources, and so should show mutual interference. In Experiment 3, prior practice on pursuit rotor and memory tasks reduced the interference with SITs from concurrent task performance. In Experiment 4, randomness within a task involving random-number generation was less when SITs were being produced concurrently than it was when they were not. The results suggest that production of SITs depends on central executive resources. 相似文献
873.
The literature is reviewed to define a sense of community in the workplace and to identify factors that may foster it. A model
is developed and estimated with survey data from a culturally diverse sample of men and women performing lower-level jobs
at a medium-sized manufacturing firm. Results of regression analyses are reported that correct for sample selection bias resulting
from the lower response rates of minority workers. Findings suggest that well-designed jobs and supportive workplace relationships
and policies are important in explaining workers' sense of community, defined as workers' perceptions of mutual commitment
between employee and employer. Informal sources of support play a larger role in explaining men's sense of community, while
formal sources of support are more important in explaining women's sense of community. Findings further suggest that African
American workers, especially women, have a difficult time experiencing a sense of community at work.
The authors thank the employees of Fel-Pro for their participation in this study and Melissa Roderick, Michael Sosin, and
anonymous reviewers for their thoughtful comments. This research was funded by the Fel-Pro/Mecklenberger Foundation and the
Lois and Samuel Silberman Fund. 相似文献
874.
Manuel Barrera Jr. Susan A. Li Laurie Chassin 《American journal of community psychology》1995,23(4):479-507
Investigated ethnicity and parental alcoholism as factors that might influence the stress vulnerability of adolescents. It
extended an initial cross-sectional study of this same sample by adding two annual assessments which allowed for additional
cross-sectional analyses and longitudinal tests. Hispanic and Caucasian adolescents (N=306 at Time 1) completed measures of their own life stress, family conflict, and alcohol use. Their parents reported on adolescents'
internalizing and externalizing symptoms. Cross-sectional analyses at Time 2, and prospective analyses involving Time 1 and
Time 2 measures were, for the most part, consistent with the original study's results. Caucasian adolescents and children
of alcoholic parents appeared to be more vulnerable to stress than Hispanic adolescents and children of nonalcoholic parents.
Family conflict was a partial explanation for this increased vulnerability.
This research was supported by National Institute on Drug Abuse Grant DA05227 to Laurie Chassin (pricipal investigator) and
Manuel Barrera, Jr. (coprincipal investigator). Susan Li was supported by an American Psychological Association Minority Fellowship
Award. Portions of this research were presented at the conference, “Resiliency in Families: Racial and Ethnic Minority Families
in America” that was held at the University of Wisconsin, May 31–June 2, 1994. 相似文献
875.
There has been a paucity of research that has investigated whether skilled performers of a complex sports skill can readily change their technique. This study was designed to investigate whether swimmers skilled in the conventional breaststroke technique could adjust readily to the wave action technique. Nine masters swimmers with well established and stable movement patterns for the conventional technique were coached in the wave action breaststroke technique. The swimmers were videotaped from the side during maximum speed trials of the conventional breaststroke technique before coaching and the wave action technique after ten 45-minute coaching sessions. The amplitude and phase of the waveforms comprising the vertical displacements of the body parts were determined by Fourier analysis. In response to the coaching, the amplitude of the fundamental frequency of the vertex of the head, shoulders, hips, and knees increased significantly (p < 0.01). The percentage of power contained in the fundamental frequency of the shoulder and hip vertical displacements also increased significantly (p < 0.01). All subjects changed the relative phase of the fundamental frequencies of the vertex, shoulder, and hip vertical displacements. It was concluded that in this complex skill, major changes to the low frequency waveforms comprising the motion were achieved readily. 相似文献
876.
ABSTRACT Biomedical experimentation on animals is justified, researchers say, because of its enormous benefits to human beings. Sure, animals suffer and die, but that is morally insignificant since the benefits of research incalculably outweigh the evils. Although this utilitarian claim appears straightforward and relatively uncontroversial, it is neither straightforward nor uncontroversial. This defence of animal experimentation is likely to succeed only by rejecting three widely held moral presumptions. We identify these assumptions and explain their relevance to the justification of animal experimentation. We argue that, even if non-human animals have considerably less moral worth than humans, experimentation is justified only if the benefits are overwhelming. By building on and expanding on arguments offered in earlier papers, we show that researchers cannot substantiate their claims on behalf of animal research. We conclude that there is currently no acceptable utilitarian defence of animal experimentation. Moreover, it is unlikely that there could be one. Since most apologists of animal experimentation rely on utilitarian justifications of their practice, it appears that biomedical experimentation on animals is not morally justified . 相似文献
877.
878.
Mary Turner DePalma Scott F. Madey Susan Bornschein 《Personality and individual differences》1995,18(6)
To examine whether guilt would inhibit immoral behavior, subjects were differentiated on their feelings of anticipatory (AG) and posttransgressional (PTG) guilt and subsequently placed in an anagram task shown to induce a high level of cheating. Results indicated that neither pre- nor post-test AG was related to cheating behavior, and test-retest administration indicated that the AG scale was unreliable. The PTG scale, however, was found to be a temporally reliable measure of guilt. In order to assess the relative contributions of pre-test posttransgressional guilt, the ability to persist, and gender to cheating behavior, a saturated multiple regression model of centered predictor effects and interaction terms was constructed. Results revealed a significant gender × persistence interaction. The cheating behavior of males was not significantly influenced by the ability to persist. On the other hand, females who exhibited a strong ability to persist rarely cheated, while those who were unable to persist cheated a great deal. Finally, subjects who felt the most posttransgressional guilt cheated more frequently. These findings provide additional evidence that guilt may be positively related to cheating behavior. 相似文献
879.
Although there is considerable empirical support for the existence of social stereotypes about different types of mothers, the content of those stereotypes is less clear. The purpose of this study was to identify the content of stereotypes related to different types of mothers. Stereotyped attributes of married mothers, stepmothers, divorced mothers, and never married mothers were generated by several samples and combined into one list. A subsequent sample was asked to indicate the percentage of each type of mother possessing each characteristic. The content of mother stereotypes was examined, and the results discussed in light of effects on social interactions, the self-image of women, and future attempts to assess family-related stereotypes. 相似文献
880.