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Consistency is often pictured as an indispensable requisite for rationality. The paper argues that this is overly rigoristic. Inconsistency can be treated as a matter of isolable singularities rather than an all-destructive disaster. The paper, supports and illustrates a perspective on which consistency can be seen as a desideratum rather than a totaly non-negotiable demand. The argumentation of the paper casts consistency in the role of a cognitive ideal rather than a sine qua non condition of rational process.  相似文献   
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The self-perceived and independently observed cognitive and social competence of young adolescents as a function of parental conflict and recent divorce was investigated. Subjects were 40 young adolescents between the ages of 11 years 1 month and 15 years 1 month. A 2×2 factorial design was used, with the independent variables being parental marital status (married vs. recently divorced) and parental conflict (high vs. low). Dependent variables included the following measures of adolescent competence: adolescent-completed measures of self-perceived competence, teacher-completed measures, behavioral observations, and school grades. The results indicated that the level of parental conflict, rather than parental marital status, appears to be the critical variable associated with adolescents' independently observed levels of cognitive and social competence. In regard to adolescents' self-perceived levels of cognitive and social competence, parental marital status was found to be the critical variable. The implications of these findings are discussed.This research was supported by the William T. Grant Foundation and the University of Georgia's Institute for Behavioral Research.  相似文献   
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Although the importance of the Drosophila mushroom body in olfactory learning and memory has been stressed, virtually nothing is known about the brain regions to which it is connected. Using Golgi and GAL4–UAS techniques, we performed the first systematic attempt to reveal the anatomy of its extrinsic neurons. A novel presynaptic reporter construct, UAS-neuronal synaptobrevin–green fluorescent protein (n-syb–GFP), was used to reveal the direction of information in the GAL4-labeled neurons. Our results showed that the main target of the output neurons from the mushroom body lobes is the anterior part of the inferior medial, superior medial, and superior lateral protocerebrum. The lobes also receive afferents from these neuropils. The lack of major output projections directly to the deutocerebrum’s premotor pathways discourages the view that the role of the mushroom body may be that of an immediate modifier of behavior. Our data, as well as a critical evaluation of the literature, suggest that the mushroom body may not by itself be a “center” for learning and memory, but that it can equally be considered as a preprocessor of olfactory signals en route to “higher” protocerebral regions.  相似文献   
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Evolution, Discovery, and Interpretations of Arthropod Mushroom Bodies   总被引:13,自引:0,他引:13       下载免费PDF全文
Mushroom bodies are prominent neuropils found in annelids and in all arthropod groups except crustaceans. First explicitly identified in 1850, the mushroom bodies differ in size and complexity between taxa, as well as between different castes of a single species of social insect. These differences led some early biologists to suggest that the mushroom bodies endow an arthropod with intelligence or the ability to execute voluntary actions, as opposed to innate behaviors. Recent physiological studies and mutant analyses have led to divergent interpretations. One interpretation is that the mushroom bodies conditionally relay to higher protocerebral centers information about sensory stimuli and the context in which they occur. Another interpretation is that they play a central role in learning and memory. Anatomical studies suggest that arthropod mushroom bodies are predominately associated with olfactory pathways except in phylogenetically basal insects. The prominent olfactory input to the mushroom body calyces in more recent insect orders is an acquired character. An overview of the history of research on the mushroom bodies, as well as comparative and evolutionary considerations, provides a conceptual framework for discussing the roles of these neuropils.  相似文献   
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Since the 1970s, counseling professionals have recommended that cancer be regarded as an illness that affects the entire family. This article combines research on understanding the impact of cancer on the family that relates both to the clinical course of cancer and to the developmental stages of the family system. The combination of these 2 dimensions provides counselors with a template for (a) understanding the current literature regarding cancer's impact on the family, (b) helping counselors formulate intervention strategies for the families of cancer patients, and (c) recognizing future directions for research regarding the needs of family members of cancer patients.  相似文献   
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Children sometimes have trouble switching from one task to another, despite demonstrating an awareness of current task demands. This behavior could reflect problems either directly inhibiting previously relevant information or sufficiently activating graded working memory representations for the current task. We tested competing predictions from each account, using a computerized card-sorting task in which we assessed children’s task switching abilities and their response speed to simple questions about current task demands. All children answered these questions correctly, but children who successfully switched tasks responded more quickly to questions than did children who perseverated on previous tasks, even after factoring out processing speed and age. This reaction time difference supports graded working memory accounts, with stronger representations of current task demands aiding both task-switching and responses to questions. This result poses a challenge for directed inhibition accounts, because nothing needs to be inhibited to answer simple questions that lack conflicting information.  相似文献   
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Vitevitch and Luce (1998) showed that the probability with which phonemes co-occur in the language (phonotactic probability) affects the speed with which words and nonwords are named. Words with high phonotactic probabilities between phonemes were named more slowly than words with low probabilities, whereas with nonwords, just the opposite was found. To reproduce this reversal in performance, a model would seem to require not merely sublexical representations, but sublexical representations that are relatively independent of lexical representations. ARTphone (Grossberg, Boardman, & Cohen, 1997) is designed to meet these requirements. In this study, we used a technique called parameter space partitioning to analyze ARTphone’s behavior and to learn if it can mimic human behavior and, if so, to understand how. To perform best, differences in sublexical node probabilities must be amplified relative to lexical node probabilities to offset the additional source of inhibition (from top-down masking) that is found at the sublexical level.  相似文献   
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