测验同质性系数及其区间估计

在决定将多维测验分数合并成测验总分时, 应当考虑测验同质性。如果同质性太低, 合成总分没有什么意义。同质性高低可以用同质性系数来衡量。用来计算同质性系数的模型是近年来受到关注的双因子模型(既有全局因子又有局部因子), 测验的同质性系数定义为测验分数方差中全局因子分数方差所占的比例。本文用Delta法推导出计算同质性系数的标准误公式, 进而计算其置信区间。提供了简单的计算同质性系数及其置信区间的程序。用一个例子说明如何估计同质性系数及其置信区间, 通过模拟比较了用Delta法和用Bootstrap法计算的置信区间, 发现两者差异很小。     

情绪调节困难对大学生手机成瘾的影响:相貌负面身体自我和社交回避与苦恼的链式中介作用

为考察相貌负面身体自我、社交回避与苦恼在情绪调节困难和手机成瘾关系中的链式中介效应,使用情绪调节困难量表、相貌负面身体自我量表、社交回避与苦恼量表和大学生手机成瘾倾向量表对734名大学生进行问卷调查。研究显示：（1）情绪调节困难会正向预测大学生手机成瘾;（2）相貌负面身体自我是情绪调节困难与大学生手机成瘾之间关系的中介变量;（3）社交回避与苦恼是相貌负面身体自我与大学生手机成瘾之间关系的中介变量;（4）社交回避与苦恼是情绪调节困难与大学生手机成瘾之间关系的中介变量。因此,相貌负面身体自我和社交回避与苦恼在情绪调节困难与大学生手机成瘾之间起链式中介作用,这些结果对于大学生手机成瘾的预防与干预具有重要的价值。     

大小判断任务中正负号及其异同对SNARC效应的影响

SNARC效应(Spatial-Numerical Association of Response Codes)是指被试对数字做按键反应时,对于较小的数字,按左键的速度快于按右键;对于较大的数字,按右键的速度快于按左键。本研究以ERP作为测量手段,采用修正的大小判断任务,旨在探究数字正负号及其异同对SNARC效应的影响。行为结果发现,在反应时上,当目标数字与基线数字正负号相同且基线数字为+5时,一致条件显著快于不一致条件。ERP结果发现,当目标数字与基线数字正负号相同时,无论基线数字为+5还是–5,在反应选择阶段,不一致都比一致条件更负且均诱发了P3。当目标数字与基线数字正负号相异时,若基线数字为+5,一致比不一致条件在刺激呈现阶段诱发了波幅显著更小的N300;若基线数字为–5,一致比不一致条件在反应执行阶段诱发了更正的LPP。无论目标数字与基线数字正负号相同还是相异,在反应选择阶段,不一致都比一致条件更负且均诱发了P3,表明出现了SNARC效应。同时,SNARC效应的出现激活了额叶头皮位置,负数加工伴随左额叶的激活,而正数加工伴随右额叶的激活,溯源分析结果进一步表明SNARC效应定位于额叶与顶叶。这些结果说明负数按实际大小表征在心理数字线上,支持了负数空间表征的个体发展论假说;表明符号捷径机制会改变SNARC效应的发生时间;同时证明了负数与正数的空间表征具有不同的优势半球。     

有关镜像神经元起源问题上的争论

文章阐述了镜像神经元起源问题上的争论及其最新进展。镜像神经元的独特之处在于,它在动作知觉和动作执行两个阶段皆被激活。这一知觉和操作的匹配机制究竟是怎样形成的?遗传论观点认为镜像神经元的匹配机制是有机体适应环境的结果,由于镜像神经元具有理解他人动作意图的特殊功能,因而被自然选择,通过遗传而得到传递。联结论则主张这种匹配机制只不过是大脑皮层动作神经元对感觉刺激形成的一种条件反射,是个体经验的结果。镜像神经元的"进化-发展观"则采纳渐成论的观点,认为镜像神经元的起源和进化不可能是联结学习单独造就的,而是进化的、生物的、发展性的、社会认知方面的和基于经验的各种因素的联合作用。     

青少年核心自我评价对生活满意度的影响:希望的中介效应

运用核心自我评价量表、儿童希望量表和青少年生活满意度问卷对934名青少年进行施测,探讨青少年群体中核心自我评价、希望和生活满意度之间的关系以及希望在核心自我评价和生活满意度之间的中介效应。结果发现:(1)青少年核心自我评价、希望和生活满意度两两之间存在显著正相关;(2)核心自我评价对生活满意度有正向影响,也通过希望对生活满意度产生正向影响,希望在核心自我评价和生活满意度之间起中介效应。     

药物滥用者的歧视错觉:来自面部表情加工的证据

通过系统梳理酒精、尼古丁、大麻、可卡因、冰毒、摇头丸、阿片类和多药物等不同类型药物滥用者面部表情加工的研究,本文提出"歧视错觉"概念,用于解释药物滥用者对面部表情的负性化加工偏向,该观点为理解药物滥用行为激活机制提供了全新视角。未来可围绕面部表情特异性加工、面部表情加工阶段、面部表情加工的认知和神经机制以及面部表情加工训练展开相关研究,以进一步揭示药物滥用者面部表情加工的内在机制及其应用价值。     

Epigenetic regulation of reelin and brain-derived neurotrophic factor genes in long-term potentiation in rat medial prefrontal cortex

Epigenetic mechanisms have recently been known to play fundamental roles in the regulation of synaptic plasticity, and learning and memory tasks in many brain regions, such as the hippocampus, the amygdala, the insular cortex. However, epigenetic mechanism in the medial prefrontal cortex (mPFC), also a crucial neural locus for the control of cognition and emotion, is not well known. The present study investigated the epigenetic regulation of two genes, reelin and brain-derived neurotrophic factor (bdnf), both play important roles in neural plasticity, in the mPFC. The data showed that the levels of total DNA methyltransferase (DNMTs), total histone acetyltransferases (HATs), global acetylated histone 3 (H3) and global acetylated histone 4 (H4) were all changed with the induction of long-term potentiation (LTP) in the mPFC, implying that DNA methylation and histone acetylation may involve in synaptic plasticity in the mPFC. The present results further demonstrated that the demethylation status of reelin and bdnf, and acetylated H3 and acetylated H4 at the reelin and the bdnf promoters in the mPFC were enhanced by the delivery of LTP-inducing high-frequency stimulation (HFS). Consistently, infusion of DNMT inhibitor, 5-azacytidine (5-azaC), or histone deacetylases (HDACs) inhibitor, sodium butyrate (NaB), into the mPFC could interfere with LTP-associated demethylation and acetylation of reelin and bdnf genes, and the induction of LTP as well. Long-term retention of trace fear memory, which is dependent on mPFC function, was also altered by administration of these inhibitors into the mPFC. These findings suggest that epigenetic regulation of DNA demethylation and histone acetylation of target genes, such as reelin and bdnf, might underlie the mechanisms of synaptic plasticity and memory retention in the mPFC.     

Neural mechanisms underlying the higher levels of subjective well-being in extraverts: Pleasant bias and unpleasant resistance

The present study investigated the neural mechanisms that underlie the higher levels of subjective well-being in extraverts. The impact of extraversion on the human sensitivity to pleasant and unpleasant pictures of diverse emotional intensities was examined. We recorded event-related potentials (ERPs) for highly positive (HP), moderately positive (MP), and neutral stimuli in the pleasant session, and for highly negative (HN), moderately negative (MN), and neutral stimuli in the unpleasant session, while subjects (16 extraverts and 16 ambiverts) performed a standard/deviant categorization task, irrespective of the emotionality of the deviant stimuli. The results showed significant emotion effects for HP and MP stimuli at the P2 and P3 components in extraverts, but not in ambiverts. Despite a pronounced emotion effect for HN stimuli across the P2, N2, and P3 components in both samples, ambiverts displayed a significant emotion effect for MN stimuli at the N2 and P3 components that was absent in extraverts. The posterior cingulate cortices, which connect multiple neural regions that are important in interactions of emotion and extraversion, may mediate the extravert-specific emotion effect for pleasant stimuli. Thus, extraverts are less susceptible to unpleasant stimuli of mild intensity than are ambiverts, while extraverts have an additional enhanced sensitivity to pleasant stimuli, regardless of emotion intensity. Consequently, the decreased threshold for pleasant emotion and the increased threshold for unpleasant emotion might be essential neural mechanisms that underlie the higher levels of subjective well-being in extraverts.     

层次化护理团队在优质护理服务中的应用探讨

将所研究的临床科室的护理人员按照职称进行分层并组成护理团队.1年后比较实施前后护理质量和护理服务质量的相关指标.实施后,护理质量和护理服务质量均有显著提高(P＜0.01).临床科室组建层次化优质护理团队,能为患者提供更为安全、满意的护理服务,推动优质护理服务的开展.     

儿童期虐待对大学生公正世界信念的影响:有调节的中介模型

为探讨儿童期虐待对公正世界信念的作用及心理机制,本研究采用问卷法对929名大学生进行了调查,并采用潜变量模型对数据进行了分析。结果发现:(1)儿童期虐待显著负向预测大学生公正世界信念;(2)控制感在儿童期虐待与公正世界信念之间起完全中介作用;(3)家庭社会经济地位调节了儿童期虐待与控制感的关系,高家庭社会经济地位放大了儿童期虐待与控制感间的负相关。研究结果表明,可以通过预防儿童虐待和增强控制感等干预措施来提升公正世界信念,并且需要对高社会经济地位家庭的儿童虐待加大关注。