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851.
The progression of brain circuits involved in spatial learning tasks is still a matter of debate. In addition, the participation of individual regions at different stages of spatial learning remains a controversial issue. In order to address these questions, we used quantitative cytochrome oxidase histochemistry as a metabolic brain mapping method applied to rats (Rattus norvegicus) trained in a water maze for 1, 3 or 5 days of training. Sustained changes throughout training were found in the lateral septal nucleus and anteroventral thalamic nucleus. As compared to naïve or habituation groups, rats with 1 day of training in the spatial learning task showed involvement of the lateral mammillary nucleus, basolateral amygdala and anterodorsal thalamic nucleus. By 5 days of training, there were mean changes in the hippocampal CA3 field and the prefrontal cortex. The regions involved and their pattern of network interactions changed progressively over days of training. At 1-day there was an open serial network of pairwise correlations. At 3-days there was a more closed reciprocal network of intercorrelations. At 5-days there were three separate parallel networks. In addition, brain-behavior correlations showed that CA1 and CA3 hippocampal fields together with the parietal cortex are related to the mastery of the spatial learning task. The present study extends previous findings on the progressive contribution of neural networks to spatial learning.  相似文献   
852.
The aim of this essay has been the evaluation of three orientations towards happiness: pleasure, meaning and engagement, as well as their relation to life satisfaction and the perception of happiness in a sample of 320 university students. The results show that the most used kind of orientation towards happiness is pleasure, followed by meaning, and finally engagement. It has also been found that pleasure is the orientation most closely associated to happiness while engagement seems to be more related to life satisfaction. These findings aim to the distinction between the concepts of happiness and life satisfaction and lead the attention to the actions which can improve the levels of happiness.  相似文献   
853.
This study evaluated improvement in self-efficacy and personal and social responsibility among at-risk of dropping-out of school adolescents participating in a program in which Hellison's Teaching Personal and Social Responsibility Model was applied in physical education classes during the course of an academic year. Thirty at-risk adolescents aged 13-14 years old (23 boys, 7 girls) were assigned to an intervention group (12 boys and 3 girls) or a comparison group (11 boys, 4 girls), the latter of which did not participate in the program. Quantitative results showed a significant improvement in the students' self-efficacy for enlisting social resources and in self-efficacy for self-regulated learning. Qualitative results showed an improvement in responsibility behaviors of participants in the intervention group. This suggests that the model could be effective for improving psychological and social development in at-risk adolescents, and that physical education classes may be an appropriate arena for working with these young people.  相似文献   
854.
Motivational characteristics are influential in shaping adolescents' desire to persist in sport or to discontinue their sport participation. Self-determination theory (Deci & Ryan, 2000) was utilized as the theoretical framework for this study. This theory examines whether sustained participatory involvement, defined as continued participation in the sport through the next year, was influenced by individuals' self-determined motivation and by the fulfillment of the three basic psychological needs of autonomy, competence, and relatedness. Four hundred ninety two soccer players between the ages of 13 and 17 years comprised the sample. Results indicated sport dropout was explained by higher levels of amotivation, external regulation, and introjected regulation and by lower satisfaction of relatedness and autonomy needs. The findings of this study contribute to the knowledge base on sport dropout as they supported many of self-determination theory.  相似文献   
855.
Otávio Bueno 《Axiomathes》2010,20(2-3):365-383
Second-order logic has a number of attractive features, in particular the strong expressive resources it offers, and the possibility of articulating categorical mathematical theories (such as arithmetic and analysis). But it also has its costs. Five major charges have been launched against second-order logic: (1) It is not axiomatizable; as opposed to first-order logic, it is inherently incomplete. (2) It also has several semantics, and there is no criterion to choose between them (Putnam, J Symbol Logic 45:464–482, 1980). Therefore, it is not clear how this logic should be interpreted. (3) Second-order logic also has strong ontological commitments: (a) it is ontologically committed to classes (Resnik, J Phil 85:75–87, 1988), and (b) according to Quine (Philosophy of logic, Prentice-Hall: Englewood Cliffs, 1970), it is nothing more than “set theory in sheep’s clothing”. (4) It is also not better than its first-order counterpart, in the following sense: if first-order logic does not characterize adequately mathematical systems, given the existence of non-isomorphic first-order interpretations, second-order logic does not characterize them either, given the existence of different interpretations of second-order theories (Melia, Analysis 55:127–134, 1995). (5) Finally, as opposed to what is claimed by defenders of second-order logic [such as Shapiro (J Symbol Logic 50:714–742, 1985)], this logic does not solve the problem of referential access to mathematical objects (Azzouni, Metaphysical myths, mathematical practice: the logic and epistemology of the exact sciences, Cambridge University Press, Cambridge, 1994). In this paper, I argue that the second-order theorist can solve each of these difficulties. As a result, second-order logic provides the benefits of a rich framework without the associated costs.  相似文献   
856.
The role of different spatial frequency bands on face gender and expression categorization was studied in three experiments. Accuracy and reaction time were measured for unfiltered, low-pass (cut-off frequency of 1 cycle/deg) and high-pass (cutoff frequency of 3 cycles/deg) filtered faces. Filtered and unfiltered faces were equated in root-mean-squared contrast. For low-pass filtered faces reaction times were higher than unfiltered and high-pass filtered faces in both categorization tasks. In the expression task, these results were obtained with expressive faces presented in isolation (Experiment 1) and also with neutral-expressive dynamic sequences where each expressive face was preceded by a briefly presented neutral version of the same face (Experiment 2). For high-pass filtered faces different effects were observed on gender and expression categorization. While both speed and accuracy of gender categorization were reduced comparing to unfiltered faces, the efficiency of expression classification remained similar. Finally, we found no differences between expressive and non expressive faces in the effects of spatial frequency filtering on gender categorization (Experiment 3). These results show a common role of information from the high spatial frequency band in the categorization of face gender and expression.  相似文献   
857.
This study evaluates the long-term efficacy of a brief psychotherapeutic cognitive-behavioral program in group format for female victims of violence by their intimate partner. 53 battered women were randomized into one of two intervention programs: one including among others exposure technique (n = 28) and another one in which exposure procedures were substituted by communication skills training (n = 25). Additionally, both programs included: psycho-education, breath control, training to improve self-esteem, cognitive restructuring, problem-solving, planning pleasant activities, and relapse prevention. The treatment was carried out in 8 weekly sessions. Measures of posttraumatic symptoms, anxiety, depression, self-esteem and anger expression were analyzed at pre- and post-treatment, and at 1-, 3-, 6- and 12-months follow-ups. Results show a pronounced decrease of posttraumatic, depressive and anxiety symptoms, which maintained in the different measure moments, with scarce difference between the two programs. The results and their clinical implications are discussed.  相似文献   
858.
The aim of this study was to examine the psychometric properties of the Brief version of the Fear of Negative Evaluation Scale - Straightforward Items (BFNE-S) in a non-clinical Spanish population. Rodebaugh et al. (2004) recommend the use of this scale composed of 8 straightforwardly-worded items, instead of the 12-item version of the BFNE. The sample consisted of 542 undergraduate students, 71.3% of whom were women and 28.7% were men; the mean age was 21.71 (4.78) years. Exploratory factor analysis produced one factor which accounted for 51.28% of variance. The internal consistency of the scale was alpha = .89. The BFNE-S correlated with the Social Avoidance and Distress Scale (r = .44), the Personal Report of Confidence as Speaker Modified (r = .44), the Public Speaking Self-Efficacy Questionnaire (r = -.38) and both subscales of the Self-Statements during Public Speaking (SSPS-P r = -.22; SSPS-N r = .53). ANOVAs revealed significant differences in the BFNE-S amongst a non-clinical population, persons suffering from specific social phobia, non-generalized social phobia and generalized social phobia.  相似文献   
859.
The psychometric characteristics of the Children's Depression Inventory, CDI (Kovacs, 1992) in a sample of 1705 participants (792 boys and 913 girls) and a clinical sample of 102 participants (42 boys and 60 girls) between 10 and 18 years old are presented. Reliability coefficients range, for both samples, from .82 (test) to .84 (retest) in the community sample, and .85 (test, clinical sample); test-retest reliability is .81 in the community sample. The mean scores are similar to other Spanish and English ones. Girls score higher than boys. The cut-off point that best differentiates between depressive and community participants is 19, with a sensitivity of 94.7%, a specificity of 95.6%, a positive predictive value of .90, and a negative predictive value of .98.  相似文献   
860.
This article presents a theory of the perception of hybrids, resulting from cross‐breeding natural animals that pertain to different species and of children parented by couples with a mixed ethnic or racial background. The theory states that natural living beings, including humans, are perceived as possessing a deeply ingrained characteristic that is called ‘essence’ or ‘blood’ or ‘genes’ in everyday discourse and that uniquely determines their category membership. If, by whatever means, the genes or essences of two animals of different species are combined in a hybrid, the two incompatible essences collapse, leaving the hybrid in a state of non‐identity and non‐belonging. People despise this state and reject the hybrid (Study 1). This devaluation effect holds with cross‐kind hybrids and with hybrids that arise from genetically combining animals from incompatible habitats across three cultures: Austria, India and Japan (Study 2). In the social world, groups and ethnic or racial categories frequently are essentialized in an analogue way. When people with an essentialist mindset judge ethnically or racially mixed offspring, they perceive a collapse of ethnic or racial essence and, consequently, denigrate these children, as compared to children from ‘pure’ in‐group or out‐group parents (Study 3). The findings are discussed in terms of the widespread ‘yuck factor’ against genetically modified animals, in terms of the cultural concepts of monstrosity and of racism and prejudice.  相似文献   
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