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991.
present research examined the role of hippocampal NMDA-dependent synaptic potentiation on appetitive instrumental conditioning under a continuous reinforcement schedule. In the first experiment, low (.025 mg.kg) or moderate (.05 mg/kg) dosages of the NMDA receptor antagonist, MK801, failed to increase the number of training days required to reach acquisition criterion; number of training days required to reach criterion for extinction were also unaffected. In the second experiment, a higher dosage (.10 mg/kg) of MK801 or induction of long-term potentiation failed to alter the number of responses occurring during acquisition. These data suggest that hippocampal synaptic potentiation does not play a prominent role in instrumental learning with simple contingency conditions. It is suggested that hippocampal LTP reflects a perceptual process that contributes differentially to spatial cognition, classical and instrumental conditioning.  相似文献   
992.
We report the results of a prospective study of a random sample of 1353 elderly but healthy men and women who were followed up for a period of 10 yr, when mortality and cause of death were ascertained. Overall results have been reported elsewhere for mortality from cancer, coronary heart disease and other causes; here we are concerned with the personality factors predicting breast cancer, cervical cancer, cancer of the corpus uteri specifically, as well as other types of cancer in women. Ten specific hypotheses were tested, using specially constructed questionnaires for the purpose, and for most of these statistically significant support was obtained. The results justify belief that specific types of cancer may be related to specific stress/personality factors.  相似文献   
993.
Fanciful Fates     
Fanciful fates is a discussion of ideas put forward by D.Z. Phillips in his book Wittgenstein and Religion , Ch. 13 –'Authorship and Authenticity: Kierkegaard and Wittgenstein'. I begin by opposing the contention that Kierkegaard attacked Socrates (and that Josiah Thompson, one of Kierkegaard's biographers, attacked Kierkegaard) because of a worry connected with the 'the demise of foundationalism'. I then deal with Phillips's claim that a similarly motivated attack on Wittgenstein has been undertaken by me. I show that Phillips's account of my treatment of two problematic remarks by Wittgenstein is radically misconceived and I argue that his own approach to the problem is unsatisfactory.  相似文献   
994.
Abstraction Processes in Artificial Grammar Learning   总被引:2,自引:0,他引:2  
Four experiments explored the extent to which abstract knowledge may underlie subjects' performance when asked to judge the grammaticality of letter strings generated from an artificial grammar. In Experiments 1 and 2 subjects studied grammatical strings instantiated with one set of letters and were then tested on grammatical and ungrammatical strings formed either from the same or a changedletter-set.Evenwith a change ofletter-set, subjects were found to be sensitive to a variety of violations of the grammar. In Experiments 3 and 4, the critical manipulation involved the way in which the training strings were studied: an incidental learning procedure was used for some subjects, and others engaged in an explicit code-breaking task to try to learn the rules of the grammar. When strings were generated from a biconditional (Experiment 4) but not from a standard finite-state grammar (Experiment 3), grammaticality judgements for test strings were independent of their surface similarity to specific studied strings. Overall, the results suggest that transfer in this simple memory task is mediated at least to some extent by abstract knowledge.  相似文献   
995.
Johnson  Barbara E.  Kuck  Douglas L.  Schander  Patricia R. 《Sex roles》1997,36(11-12):693-707
Many myths have been identified surrounding rape, rapists, and rape victims. This study reexamines the acceptance of rape myths across gender role ideologies and selected demographic characteristics to identify core myths. Three myth categories were established and investigated: blaming the woman, excusing the man, and justifications for acquaintance rape. Findings indicate that rape myths remain prevalent and adherence to myths is related to demographic factors and gender role attitudes. Overall, respondents tend to excuse the man more than blame the woman. Males accept rape myths more than females. Racial differences emerged most strongly on the justifications for acquaintance rape dimension. Individuals with a conservative gender role ideology believe rape myths more than those with more liberal ideologies. While core myths did not emerge from the data, the most revealing finding is that summative scaling techniques used in previous studies may mask important differences, between and within the three dimensions, in rape myth acceptance among the groups studied.  相似文献   
996.
present research examined the role of hippocampal NMDA-dependent synaptic potentiation on appetitive instrumental conditioning under a continuous reinforcement schedule. In the first experiment, low (.025 mg.kg) or moderate (.05 mg/kg) dosages of the NMDA receptor antagonist, MK801, failed to increase the number of training days required to reach acquisition criterion; number of training days required to reach criterion for extinction were also unaffected. In the second experiment, a higher dosage (.10 mg/kg) of MK801 or induction of long-term potentiation failed to alter the number of responses occurring during acquisition. These data suggest that hippocampal synaptic potentiation does not play a prominent role in instrumental learning with simple contingency conditions. It is suggested that hippocampal LTP reflects a perceptual process that contributes differentially to spatial cognition, classical and instrumental conditioning.  相似文献   
997.
This article reviews key issues related to racial minorities working as consultants, provides an analysis of possible impediments to successful consultation by stage of the process, and provides examples of how majority consultants can provide support for this underrepresented group in the field. Implications for training are discussed.  相似文献   
998.
Abstract— Pennebaker's (this issue) intervention for writing about emotional experiences shows promise as a module for inclusion in therapeutic packages. There are conceptual, methodological ant practical issues to be considered, however. These issues are discussed, and parallels are drawn from the literatures on the moodregulatory function of dreams and on the effects of social support on health. Although there is evidence that anything about emotional experiences has beneficial effects on health, it is premature to recommend writing intervention as a treatment component for specific problems. What is needed at this point is systematic research to evaluate to clinical utility.  相似文献   
999.
How can we explain that an assertion on something perceived can be understood in the same manner by somebody who cannot perceive that scene? This problem bases the interest in computational linguistics in how listener modeling could possibly be harmonized with reference semantics. Mental images substituting real perception appear as a way out. The architecture of the listener model has to be adapted to the creation and use of such pictorial data structures. Furthermore, the relation between the latter and a verbal (i. e., propositional) representation must be understood. The resulting architecture of a listener model with reference semantics can be employed to solve communicational problems from three general classes in a better way, as is demonstrated by an example implementation.  相似文献   
1000.
Previous research has revealed that English-speaking preschoolers expect that a novel count noun (but not a novel adjective), applied to an individual object, may be extended to other members of the same basic or superordinate level category. However, because the existing literature is based almost exclusively on English-speakers, it is unclear whether this specific expectation is evident in children acquiring languages other than English. The experiments reported here constitute the first cross-linguistic, developmental test of the noun-category linkage. We examined monolingual French- and Spanish-speaking preschool-aged children's superordinate level categorization in a match-to-sample task. Target objects were introduced with (a) novel words presented as count nouns (e.g., “This is afopin”), (b) novel words presented as adjectives (e.g., “This is afopishone”), or (c) no novel words. Like English-speakers, French- and Spanish-speakers extended count nouns consistently to other category members. This is consistent with our prediction that the mapping between count nouns and object categories may be a universal phenomenon. However, children's extension of novel adjectives varied across languages. Like English-speakers, French-speakers did not extend novel adjectives to other members of the same category. In contrast, Spanish-speakers did extend novel adjectives, like count nouns, in this fashion. This is consistent with our prediction that the mappings between adjectives and their associated applications vary across languages. The results provide much-needed cross-linguistic support for the noun-category linkage and illustrate the importance of the interplay between constraints within the child and input from the language environment.  相似文献   
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