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111.
The neurons of cerebral cortex are largely autonomous and generate activity that is manifested in trains of microscopic axonal action potentials. The neurons interact by sparse but numerous synaptic connections to generate macroscopic dendritic activity patterns that are observed in electroencephalographic (EEG) waves. The macroscopic patterns are constructed by the populations and they shape the output of cortical neurons in parallel arrays. Sensory cortexes receive sensory information in the form of microscopic action potentials, which induce state transitions in population dynamics. Each state transition transforms sensory information to perceptual meaning. The EEG reflects both kinds of activity. The sensory input is accessed by time ensemble averaging, whereas the perceptual output is found by spatial ensemble averaging. Spatial phase gradients in the EEG are useful for identifying EEG segments in a sequence of state transitions in response to sensory input. The rapidity and flexibility with which they take place give strong reason to postulate that the mechanism for the construction of these sequences of patterns is a dynamical system operating in a chaotic domain.  相似文献   
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113.
The presence of nonobservational vocabulary is shown to be necessary for wide application of a conservative principle of theory revision.Support for this research was provided by the Office of Naval Research under contract No. N00014-87-K-0401. We thank Daniel Andler and Clark Glymour for helpful discussion.  相似文献   
114.
This paper presents a nonmonotonic deontic logic based on commonsense entailment. It establishes criteria a successful account of obligation should satisfy, and develops a theory that satisfies them. The theory includes two conditional notions of prima facie obligation. One is constitutive; the other is epistemic, and follows nonmonotonically from the constitutive notion. The paper defines unconditional notions of prima facie obligation in terms of the conditional notions.  相似文献   
115.
Employed qualitative methods to examine the role of the family in the academic success of very high-achieving African American males. Findings revealed a complex tapestry of family processes and contexts involved in each youth's journey to outstanding academic achievement. Specifically, the combined importance of parental-determined academic engagement, strict discipline, nurturance, and community connectedness appeared to counteract potentially negative contextual influences of neighborhood, peers, schools, and society. The qualitative findings tell a multifaceted, rich, and compelling story of the pathways to academic success for Black males, and highlight the need for culture-specific and ecologically based conceptualization, research, and intervention approaches.  相似文献   
116.
Ninety-five high-risk adolescents were studied to determine whether their dating aggression and its justification as a response to interpersonal problems were specific to the current partner, general to dating relationships, or part of a global age-mate (same-sex peers and opposite-sex dating partners) aggression problem. Approximately one-third of males and two-thirds of females reported physical aggression against their current dating partner. Males' aggression (and its justification) toward their current dating partner was part of a generalized pattern of dating aggression, whereas for females, physical aggression against a current dating partner (and its justification) was partner-specific and unrelated to aggression in other relationships. Findings are discussed with regard to intervention and future research on adolescent dating aggression.  相似文献   
117.
Levels and correlates of parental support, peer support, partner support, and/or spiritual support among African American and Caucasian youth were examined in three contexts: adolescent pregnancy (Study 1), first year of college (Study 2), and adolescence and young adulthood (ages 15–29; Study 3). Partially consistent with a cultural specificity perspective, in different contexts different support sources were higher in level and/or more strongly related to adjustment for one ethnic group than the other. Among pregnant adolescents, levels of spiritual support were higher for African Americans than Caucasians; additionally, peer support was positively related to well-being only for African Americans whereas partner support was positively related to well-being only for Caucasians. Among college freshmen, family support was more strongly related to institutional and goal commitment for African Americans than Caucasians; conversely, peer support was more strongly related to institutional and goal commitment among Caucasians. Among 15 to 29-year-olds, levels of parental support and spiritual support were higher among African Americans than Caucasians; additionally, spiritual support was positively related to self-esteem for African Americans but not for Caucasians. Implications and limitations of the research are discussed. The third study was supported by National Institute of Mental Health Grant RO1 MH40963. We thank Monica Greene, Shea Lyda, Wendy Stevenson, and the many undergraduate students who contributed to the three research projects. We also acknowledge the very thoughtful and helpful comments of the anonymous reviewers and the editor, Edison Trickett.  相似文献   
118.
Premise acceptability is conceptually connected to presumption. To say that a premise is acceptable just when there is a presumption in its favor is to give a first approximation to this connection. A number of popular principles of presumption suggest that whether there is a presumption for a premise, belief, or claim depends on the sources which vouch for it. Sources consist of internal belief-generating mechanisms and external testimony. Alvin Plantinga's notion of warrant lays down four conditions upon a source for the belief which it generates to be warranted. We argue that there is a presumption for a premise, belief, or claim if and only if there is a presumption of warrant for that premise,belief or claim. This amounts to the thesis that there is a presumption for a belief from a challenger's point of view if and only if there is a presumption from that person's point of view that her cognitive faculties which have generated the belief have been functioning properly, in an appropriate cognitive environment, in accord with a segment of her design plan aimed at the truth, and that these faculties are reliable. In light of our argument for this thesis, we may legitimately claim that one way to determine that there is a presumption for a belief is to determine that there is a presumption of warrant for that belief, and thus that in determining whether there is a presumption for a belief or premise, we may consider the source.  相似文献   
119.
This paper investigates how organizational climate and information quantity influences choice of decision making strategies. A simulated company with an organizational climate was manipulated to be either supportive or non-supportive of participative decision making methods. Subjects then solved problems in which information available to make a decision was manipulated. Results indicated that climate has an effect on choice of decision making strategies independent of information quantity. A second study was then conducted to assess how the climate manipulation affected subjects' decision-making. Organizational climate information appears to affect decisions in a manner analogous to Tversky and Kahneman's (1981) decision framing model.The contribution of each author is equal for this paper. The order of authorship was determined by a coin flip. This research was supported by Ohio Board of Regents and University of Akron Faculty Research grants to the second author. Portions of this paper were presented at the 1989 Society of Industrial Organizational Psychology Meetings and the 1991 Association of Management Meetings.  相似文献   
120.
The National Conference of Catholic Bishops has argued for significant government involvement in health care in order to assure respect for what they regard as the right to health care. Critics charge that the bishops are wrong because health care is not a right. In this article, it is argued that these critics are correct in their claim that health care is not a right. However, it is also argued that the premise that health care is not a right does not imply that the market is the most equitable and just system for providing health care. Natural law arguments in the tradition of Roman Catholic social teaching lead to the conclusion that a just and prosperous society has a moral obligation to provide health care even if there is no such right. Further, there are strong moral grounds for concluding that the bishops are correct in their claim that health care ought not to be considered a market commodity. It is argued that if health care ought not to be considered a commodity, then national health insurance is the best available alternative for fulfilling the social obligation to distribute health care resources justly and fairly at this time in American history. The bishops' case for government involvement can be made on the strength of the Catholic tradition in theological argumentation, independent of the claim that health care is a right.  相似文献   
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