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991.
Parenting practices have been previously linked to childhood symptomatology. However, little consideration has been given to the potential effect of individual differences within the child on this relation. The current study assessed the moderating effects of children's activity level and fear on relations between parenting practices and childhood aggression and depressive symptoms using a sample of 64 fourth-, and fifth-grade boys. The findings showed that poorly monitored active boys and fearful boys who were exposed to harsh discipline exhibited high levels of aggression. Boys characterized by high fear who were exposed to harsh discipline or whose parents were extremely overinvolved showed elevated levels of depressive symptoms. These findings suggest that integrating children's individual differences with parenting models enhances our understanding of the etiology of childhood symptomatology. The intervention implications of such an integration are discussed.  相似文献   
992.
To replicate and extend results of earlier studies on amino acid effects on post-stress ulcers, rats were subjected to i.p. injections of (a) saline, (b) tryptophan, (c) tyrosine + valine or(d) tryptophan + tyrosine + valine, either 30 minutes before or immediately after one hour of water restraint stress. Gastric lesions, brain norepinephrine, serotonin and 5-hydroxyindoleacetic acid (5-HIAA) were examined after one hour of poststress rest. We hypothesised that post-stress lesions could be aggravated by central noradrenergic hypoactivity and serotonergic hyperactivity during the post-stress period. Other studies have indicated that tyrosine + valine reduces central serotonergic activity, while additional tryptophan blocks this effect. We therefore expected post-stress lesions to be reduced in tyrosine + valine but not in tryptophan + tyrosine + valine treated animals. Although these expectations were met tentatively in animals injected prior to stress, thus replicating tyrosine + valine effects we had observed earlier, opposite results were found in animals treated post-stress. The brain analyses indicate that the data cannot be explained by a norepinephrine/serotonin imbalance hypothesis. The time dependency of the effects underlines the need for caution in clinical applications of these amino acid treatments.  相似文献   
993.
The hippocampus, which is critically involved in learning and memory processes, is known to be a target for the neuromodulatory actions of steroid hormones produced by the adrenal glands and gonads. Much of the work of B.S. McEwen and collaborators has focused on the role of glucocorticosteroids and estrogen in modulating hippocampal plasticity and functions. In addition to hormones derived from the endocrine glands, cells in the hippocampus may be exposed to locally synthesized neurosteroids, including pregnenolone, dehydroepiandrosterone and their sulfated esters as well as progesterone and its reduced metabolites. In contrast to hormones derived from the circulation, neurosteroids have paracrine and/or autocrine activities. In the hippocampus, they have been shown to have trophic effects on neurons and glial cells and to modulate the activity of a variety of neurotransmitter receptors and ion channels, including type A gamma-aminobutyric acid, N-methyl-D-aspartate and sigma receptors and N- and L-type Ca2+ channels. There is accumulating evidence that some neurosteroids, in particular pregnenolone sulfate, have strong influences on learning and memory processes, most likely by regulating neurotransmission in the hippocampus. However, the hippocampus is not the only target for the mnesic effects of neurosteroids. Associated brain regions, the basal nuclei of the forebrain and the amygdaloid complex, are also involved. Some neurosteroids may thus be beneficial for treating age- or disease-related cognitive impairments.  相似文献   
994.
995.
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   
996.
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   
997.
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   
998.
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   
999.
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   
1000.
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   
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