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971.
972.
Research suggests that, in some cases, mechanical restraints may function as positive reinforcers. In this study, we conducted a functional analysis of severe aggression exhibited by an individual with a history of wearing arm splints. The results of this functional analysis demonstrated that his aggression was maintained by access to the arm splints. Copyright © 2008 John Wiley & Sons, Ltd.  相似文献   
973.
Cognitive functions usually involve various synaptic proteins and neurotrophic factors in the hippocampus. However, whether treadmill exercise can improve learning and memory by upregulating some of these molecules remain unraveled. To address this question, male BALB/c mice were divided into control and exercise groups, the latter group went through 4 weeks of treadmill exercise training. At the end of exercise training period, they were either tested for passive avoidance (PA) performance or sacrificed for quantifying the hippocampal levels of brain-derived neurotrophic factor (BDNF), tropomyosin-related kinase B (TrkB, the BDNF receptor), synaptotagmin (a Ca2+-dependent synaptic vesicle protein), and SNAP-25 (a presynaptic vesicular fusion protein). Our results showed that treadmill exercise training (1) increased the retention latency without affecting the fear acquisition in the PA test, (2) transiently increased the hippocampal BDNF level at 1, 2, and 4 h after the completion of exercise training, and (3) persistently increased the hippocampal protein levels of full-length TrkB, phosphorylated TrkB and synaptotagmin, but not truncated TrkB or SNAP-25. Moreover, the protein expression level of full-length TrkB or synaptotagmin was positively correlated with PA performance in mice. Finally, inhibition of TrkB signaling by K252a abolished the exercise-facilitated PA performance and upregulation of TrkB and synaptotagmin. Taken together, these data suggest that the upregulation of TrkB and synaptotagmin in the hippocampus contributes to the exercise-facilitated aversive memory.  相似文献   
974.
Invertebrates are valuable models for increasing our understanding of the effects of ethanol on the nervous system, but most studies on invertebrates and ethanol have focused on the effects of ethanol on locomotor behavior. In this work we investigate the influence of an acute dose of ethanol on appetitive olfactory learning in the honey bee (Apis mellifera), a model system for learning and memory. Adult worker honey bees were fed a range of doses (2.5%, 5%, 10%, or 25%) of ethanol and then conditioned to associate an odor with a sucrose reward using either a simple or differential conditioning paradigm. Consumption of ethanol before conditioning significantly reduced both the rate of acquisition and the asymptotic strength of the association. Honey bees also exhibited a dose dependent reduction in arousal/attention during conditioning. Consumption of ethanol after conditioning did not affect recall 24h later. The observed deficits in acquisition were not due to the affect of ethanol on gustatory sensitivity or motor function. However, honey bees given higher doses of ethanol had difficulty discriminating amongst different odors suggesting that ethanol consumption influences olfactory processing. Taken together, these results demonstrate that an acute dose of ethanol affects appetitive learning and olfactory perception in the honey bee.  相似文献   
975.
Previous psychometric studies of the Rosenberg Self-Esteem Scale (RSES; 1965) have shown that items with positive and negative words tend to form 2 factors instead of a single factor for global self-esteem. Recent studies using confirmatory factor analysis have indicated that there is an additional method effect behind negatively worded items. However, researchers conducted these studies using Western participants. Because J. L. Farh and B. S. Cheng (1997) suggested that culturally Chinese people tend to exhibit a modesty bias in self-evaluation, especially on positively worded items, researchers may infer that a wording effect of positively worded items would be evident for culturally Chinese people. The author examined the wording effect in the RSES for culturally Chinese people by comparing different confirmatory factor models. The author analyzed data from 2 independent samples of students at the National Taiwan University (ns = 393, 441) and a national sample of juniors recruited from 140 universities and colleges in Taiwan in 2004 (n = 28,862). Results showed that in addition to a global factor for self-esteem, method effects of positively and negatively worded items should also be specified for a model fitting culturally Chinese people.  相似文献   
976.
Differential emotions theory (DET) (The face of emotion. Appleton‐Century‐Crofts: East Norwalk, CT, 1971) posits that the smile functions in part to communicate and/or reflect social affiliation and plays an important role in children's social development. While children's positive emotion expressions have received attention from peer relations researchers in observational studies and within correlational designs, there is almost no experimental evidence for the impact of the smile. Building on existing studies, the present study examined DET predictions within an experimental design. More specifically, we examined the impact smiles have on lower‐income preschool children's nominations for preferred playmates. Both boys and girls tended to nominate unfamiliar playmates who smiled. Additionally, some evidence suggested that preference for smiling playmates seemed more critical to girls' than boys' social functioning. Unlike among boys, teachers rated girls who exhibited a greater preference for smiling playmates as higher in social competence. Copyright © 2008 John Wiley & Sons, Ltd.  相似文献   
977.
This study investigated associations between mother–infant interactions and children's subsequent understanding of mind and emotion. Mothers' tendency to comment on their infants' internal world and their general sensitivity to their infants' internal states were measured through coded play interactions at 10 months. The latter measurement included ratings on four aspects of maternal behaviour: mindful facilitation, joint attention commenting, pacing, and affect catching. In contrast to mothers' internal state language, these behaviours did not tap mothers' explicit linguistic representation of their infants' mental states. At 54 months, children's understanding of mind and emotion was measured through a range of false‐belief tasks and an emotion‐understanding task. Multivariate analysis revealed direct positive links between mothers' sensitivity to their infants' internal states and children's later understanding of mind. Copyright © 2008 John Wiley & Sons, Ltd.  相似文献   
978.
聋童执行功能发展:聋童与正常儿童的比较   总被引:6,自引:0,他引:6  
利用标准Dimensional Change Card Sort任务(DCCS),对76名智力正常的3~8岁聋童和78名3~5.5岁的正常儿童进行了对比测试,旨在考察聋童执行功能发展的年龄特征与发展水平。结果发现,3岁组的聋童和正常儿童在DCCS任务上的表现没有显著性差异,但正常儿童在4~4.5岁时进入一个迅速发展期,而聋童要在6岁时才有快速的发展,到7岁后才相当于正常儿童5岁的发展水平,大约滞后2年。研究认为,造成聋童执行功能发展滞后的原因主要有:(1)语言符号系统和聋童特有的符号系统之间可能存在的差异;(2)聋童可能存在计划和灵活性的缺陷;(3)聋童可能存在命名和标识策略上的困难和注意机制的缺陷。结合关于聋童心理理论发展滞后于正常儿童7年以上的报道,心理理论发展和执行功能发展在聋童身上表现出较大的不一致性。  相似文献   
979.
We address the question why fear dominates hope in the life of individuals and collectives on the basis of the accumulated knowledge in the psychology, neurology and sociology of emotions. This knowledge suggests that fear, as primary emotion, is grounded in the experienced present and based on the memorized past, processed both consciously and unconsciously, causes freezing and conservatism, and sometimes leads to pre‐emptive aggression. Hope, in contrast, as a secondary emotion, involves cognitive activity, which requires anticipation and the search for new ideas and thus is based on complex processes of creativity and flexibility. Therefore, hope is often preceded and inhibited by spontaneous, automatically activated and faster fear. Fear and hope can each become a collective emotional orientation, and as such organize society's views and direct its actions. Societies involved in intractable conflict are dominated by a collective fear orientation. This orientation is functional for society's coping with the stressful and demanding situation—but it may serve as a psychological obstacle to any peace process, once it starts. The case of the collective fear orientation in the Jewish Israeli society is presented as an example. The article ends with a presentation of a particular approach, suggesting that individuals and collectives can overcome their fear with much determination, and establish an orientation of hope which allows change in situations dominated by fear. Copyright © 2006 John Wiley & Sons, Ltd.  相似文献   
980.
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