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921.
Growing evidence indicates that antagonists of the 5-hydroxytryptamine (serotonin) receptor6 (5-HT6) improve memory and reverse amnesia although the mechanisms involved are poorly understood. Hence, in this paper RT-PCR was used to evaluate changes in mRNA expression of 5-HT6 receptor in trained and untrained rats treated with the 5-HT6 receptor antagonist SB-399885 and amnesic drugs scopolamine or dizocilpine. Changes in mRNA expression of 5-HT6 receptor were investigated at different times in prefrontal cortex, hippocampus and striatum. Data indicated that memory in the Pavlovian/instrumental autoshaping task was a progressive process associated to reduced mRNA expression of 5-HT6 receptor in the three structures examined. SB-399885 improved long-term memory at 48 h, while the muscarinic receptor antagonist scopolamine or the non-competitive NMDA receptor antagonist dizocilpine impaired it at 24 h. Autoshaping training and treatment with SB-399885 increased 5-HT6 receptor mRNA expression in (maximum increase) prefrontal cortex and striatum, 24 or 48 h. The scopolamine-induced amnesia suppressed 5-HT6 receptor mRNA expression while the dizocilpine-induced amnesia did not modify 5-HT6 receptor mRNA expression. SB-399885 and scopolamine or dizocilpine were able to reestablish memory and 5-HT6 receptor mRNA expression. These data confirmed previous memory evidence and of more interest is the observation that training, SB-399885 and amnesic drugs modulated 5-HT6 receptor mRNA expression in prefrontal cortex, hippocampus and striatum. Further investigation in different memory tasks, times and amnesia models together with more complex control groups might provide further clues.  相似文献   
922.
The present study investigated the relative contribution of bottom-up and top-down control to task selection in the voluntary task-switching (VTS) procedure. In order to manipulate the efficiency of top-down control, a concurrent working memory load was imposed during VTS. In three experiments, bottom-up factors, such as stimulus repetitions, repetition of irrelevant information, and stimulus-task associations, were introduced in order to investigate their influence on task selection. We observed that the tendency to repeat tasks was stronger under load, suggesting that top-down control counteracts the automatic tendency to repeat tasks. The results also indicated that task selection can be guided by several elements in the environment, but that only the influence of stimulus repetitions depends on the efficiency of top-down control. The theoretical implications of these findings are discussed within the interplay between top-down and bottom-up control that underlies the voluntary selection of tasks.  相似文献   
923.
Depending on the brain networks involved, aging is not accompanied by a general decrease in learning and memory capabilities. We demonstrated previously that learning and retrieval of taste potentiated odor aversion (TPOA) is preserved, and even slightly improved, in senescent rats showing some memory deficiencies in cognitive tasks (Dardou, Datiche, & Cattarelli, 2008). TPOA is a particular behavior in which the simultaneous presentation of odor and taste cues followed by a delayed visceral illness leads to a robust aversion towards both conditioned stimuli, which permits diet selection and animal survival. The present experiment was performed in order to investigate the stability or the evolution of the brain network underlying TPOA retrieval during aging. By using immunocytochemical detection of Fos and Egr1 proteins we mapped the cerebral activation induced by TPOA retrieval elicited by the odor presentation in the young, the adult and the senescent rats. The pattern of brain activation changed and the number of activated areas decreased with age. Nevertheless, the piriform cortex and the basolateral amygdala nucleus were always activated and seemed essential for TPOA retrieval. The hippocampus and the neocortical areas could have different implications in TPOA memory in relation to age. The patterns of expression of Fos and Egr1 were different, suggesting their differential involvement in TPOA retrieval. Data are discussed according to the possible roles of the brain areas studied and a model of schematic brain network subtending TPOA retrieval induced by the odor cue is proposed.  相似文献   
924.
925.
A consolidated memory recalled by a reminder enters a vulnerability phase (labilization), followed by a process of stabilization (reconsolidation). Several authors have suggested that the labilization of the consolidated memory makes the incorporation of new information possible. Here, we demonstrate updating in the framework of memory declarative reconsolidation in humans by giving an opportune verbal instruction. Volunteers learn an association between five cue-syllables (L1) and their respective response-syllables. Twenty-four hours later, the paired-associate verbal memory is labilized by exposing the subjects to the reminder, and then they receive the verbal Instruction of adding three new cue-response syllables (INFO) with their respective responses to the former list of five. The new information is incorporated into the single former L1-memory and both INFO and L1 are successfully retrieved on the third day. However, when the Instruction is not preceded by a proper reminder, or when the instruction omits the order of adding the INFO into the former L1-memory, we observed interference in retrieval of both the original and the new information, suggesting that they are encoded independently and coexist as separate memories.  相似文献   
926.
This study examines the relationships among stressors, coping strategies, self-efficacy and burnout in a sample of 724 Spanish primary and secondary teachers. We understood stressors as barriers perceived by teachers that interfere with their work meeting learning objectives and which cause them stress and burnout. An analysis of teacher responses using hierarchical regression revealed that pedagogical barriers had significant positive effects on the burnout dimensions. Furthermore, the results show not only the moderator role played by coping strategies in the pedagogical barriers-burnout dimensions relationship, but also the association between self-efficacy and the coping strategies used by teachers. Practical implications are discussed.  相似文献   
927.
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   
928.
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   
929.
Since their child has been diagnosed as having an autistic spectrum disorder (ASD), parents are confronted with important and chronic stress in their everyday life. To face it, they use coping strategies. Using qualitative analyse, this article exposes preliminary results on changes in coping strategies of ASD families and presents how parents manage to adjust their coping.  相似文献   
930.
Do gifted teenagers (IQ ≥130) harbor a different attitude toward learning as compared to their mainstream peers? Can the attitudes toward learning held by these adolescents improve or hinder their academic performance? Eighty-four gifted high school students and 84 mainstream high school students between the ages of 13 and 18 years were asked to draw up “an assessment of knowledge” (Charlot, B., Bautier, E., Rochex, J.Y., 1992. École et savoir dans les banlieues… et ailleurs. Colin, Paris.). The collected textual data was submitted to both a quantitative and a lexicometric analysis (Alceste software). The gifted students revealed themselves as being more reflexive and “scholarly” relation to knowledge (op. cit.) than their mainstream peers. High achievers attach more value to academic knowledge and have greater confidence in their ability to learn.  相似文献   
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