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991.
小学生代数运算规则的样例学习 总被引:1,自引:0,他引:1
采用完整或不完整样例,对180名六年级小学生用样例学习两种代数运算规则进行了实验研究。结果显示:多数被试难以学会“平方差”运算规则,只有少数被试学会了“完全平方和”运算规则;反馈对不完整样例的学习效果有促进作用;用不完整样例学习难度不同的规则,其效果不同;在无反馈条件下,完整样例的学习效果都好于不完整样例;在有反馈的情况下,只有删除一步运算步骤样例的学习效果比完整样例的学习效果好 相似文献
992.
脂多糖免疫激活导致抑郁性行为的动物研究:剂量和时程效应 总被引:3,自引:1,他引:2
“抑郁症细胞因子假说”的提出为抑郁障碍的病因学研究提供了一个新的方向,为了探讨脂多糖(lipopolyaccharide,LPS)诱导的免疫激活与抑郁性行为产生之间的关系,本研究采用50只SD大鼠随机分为五组LPS400,LPS200,LPS50,LPS10,LPS0,分别于实验期第0天和第3天注入LPS400ug/kg,,200ug/kg,50ug/kg,10ug/kg和生理盐水。以糖精水偏爱,旷场行为和高架十字迷宫评定大鼠LPS注射后2小时,24小时,48小时的行为变化。结果显示一次LPS注射后2小时,LPS50,LPS200,LPS400组动物与生理盐水组动物相比较,其糖精水偏爱分数(p<0.01),旷场中的水平活动距离(p<0.01)和直立行为(p<0.01)以及高架十字迷宫中的闭合臂进入次数(p<0.01)和开放臂进入次数显著下降(p<0.01);重复注射后2小时LPS注射组动物的闭合臂进入次数显著降低(p<0.01);但LPS10组与生理盐水组动物在行为上没有差异,50ug/kg,200ug/kg和400ug/kg剂量的各组之间没有差异。LPS注射后24小时和48小时以及重复注射后大鼠的行为没有发现显著变化。提示LPS诱导的免疫激活对抑郁行为产生有一定的作用。免疫激活的细胞因子能够导致动物出现明显的抑郁性行为,但是这种行为缺乏长时程效应,因此LPS诱导的抑郁障碍的动物模型应用是非常有限的。免疫激活的前炎性细胞因子可能是导致抑郁障碍产生的其中一个原因而不是唯一原因。 相似文献
993.
吗啡行为及条件性行为敏感化效应及其个体差异 总被引:3,自引:1,他引:2
目的:考察吗啡处理下,大鼠行为敏感化及条件性行为敏感化效应及其个体差异性表现。方法:根据大鼠在初次抵达的新颖环境中水平活动量的高低,将大鼠划分为高反应大鼠(High responder, HR)和低反应大鼠(Low responder, LR),应用自动监测大鼠活动箱,分别考察HR和LR大鼠在行为及条件性行为敏感化效应表达上的差异。结果:(1)连续5天吗啡给药,LR大鼠活动量显著升高,HR大鼠无此效应;(2)条件测试日(第6天),给药与环境匹配大鼠,活动量较给药与环境非匹配组动物和对照组动物显著为高;此效应在HR和LR大鼠同时存在;(3)从给予吗啡到给予盐水,发现LR大鼠活动量显著下降,而HR大鼠活动量无显著改变。结论:在连续给药下,LR大鼠较HR大鼠,在行为敏感化效应的形成中,具有更为显著的效应,此效应为LR动物对吗啡更高的药物效应,而非条件效应所致,同时HR和LR大鼠都可以对吗啡条件性线索产生应答,产生条件性行为敏感化效应。 相似文献
994.
四则混合运算规则的样例学习 总被引:7,自引:2,他引:5
采用有或无“运算步骤标记”两种样例和“交互式”样例呈现方式,对48名二年级小学生通过样例学习四则混合运算规则进行了实验。结果表明,多数被试可以通过样例学会“小括号”和“中括号”四则混合运算规则,但多数被试难以学会“无括号”四则混合运算规则;运算步骤标记对学习“无括号”运算规则的促进作用明显,但对学习“小括号”运算规则的促进作用不明显;运算规则学习的难度不同,所需样例的数量也不同。 相似文献
995.
Geetha B. Ramani Emily N. Daubert Grace C. Lin Snigdha Kamarsu Alaina Wodzinski Susanne M. Jaeggi 《Developmental science》2020,23(4)
Sources that contribute to variation in mathematical achievement include both numerical knowledge and general underlying cognitive processing abilities. The current study tested the benefits of tablet‐based training games that targeted each of these areas for improving the mathematical knowledge of kindergarten‐age children. We hypothesized that playing a number‐based game targeting numerical magnitude knowledge would improve children's broader numerical skills. We also hypothesized that the benefits of playing a working memory (WM) game would transfer to children's numerical knowledge given its important underlying role in mathematics achievement. Kindergarteners from diverse backgrounds (n = 148; 52% girls; Mage = 71.87 months) were randomly assigned to either play a number‐based game, a WM game, or a control game on a tablet for 10 sessions. Structural equation modeling was used to model children's learning gains in mathematics and WM across time. Overall, our results suggest that playing the number game improved kindergarten children's numerical knowledge at the latent level, and these improvements remained stable as assessed 1 month later. However, children in the WM group did not improve their numerical knowledge compared to children in the control condition. Playing both the number game and WM game improved children's WM at the latent level. Importantly, the WM group continued to improve their WM for at least a month after playing the games. The results demonstrate that computerized games that target both domain‐specific and domain‐general skills can benefit a broad range of kindergarten‐aged children. 相似文献
996.
结合注意网络测量工具和听视ODDBALL干扰范式,考察偏差声音干扰刺激的出现对注意网络系统不同功能的影响。结果发现,声音刺激序列下,视觉线索唤醒效应均消失; 标准声音刺激下,不存在线索的脱离和转移效应; 偏差声音刺激下,出现线索脱离和转移效应。研究表明,注意网络中的警觉功能具有超通道加工机制,偏差刺激下视觉注意系统中注意定向和线索转移效应的出现表明偏差干扰效应主要由偏差刺激引起的注意脱离和注意转移损耗部分引起。 相似文献
997.
采用感知教师支持、学习投入、学业自我效能感和成就目标定向问卷对498名高中生进行问卷调查,探讨感知教师支持对学习投入的影响,以及学业自我效能感和成就目标定向的链式中介效应。结果显示:(1)感知教师支持能通过学业自我效能感间接预测高中生学习投入,感知教师支持可以通过掌握趋近、表现趋近、表现回避间接预测高中生学习投入;(2)学业自我效能感→掌握趋近、学业自我效能感→表现趋近、学业自我效能感→表现回避三者分别在感知教师支持与学习投入之间起链式中介作用,学业自我效能感→掌握回避的中介效应则不显著。上述结果表明,感知教师支持不仅能分别通过学业自我效能感、掌握趋近、表现趋近、表现回避预测高中生学习投入,还能通过学业自我效能感和成就目标定向的链式中介作用间接预测高中生学习投入。 相似文献
998.
Although some studies have revealed that traditional filial piety belief is weakening, few have explored whether and how the role of the belief in social life has changed correspondingly. The present study used questionnaires to examine solutions to filial piety dilemmas and the roles of contextual theme, filial piety beliefs, and generation in a sample of 123 young and 92 middle‐aged Chinese adults. With respect to the solutions adopted to solve parent?child conflicts, preferences varied depending on the dilemma themes. Specifically, participants were more likely to select a self‐sacrifice (rather than an ego‐centered) solution for respect dilemmas than for caring dilemmas, and least likely to do so for obedience dilemmas. Participants were also likely to select a balancing (rather than an ego‐centered) solution for respect or caring dilemmas than for obedience dilemmas. In addition, the concordance between beliefs and solutions was exhibited in reciprocal, but not authoritarian, filial piety beliefs. Individuals with stronger reciprocal filial piety beliefs were more likely to select self‐sacrifice or balancing solutions than ego‐centered solutions whereas authoritarian filial piety showed no influence on solutions for either young or middle‐aged adults. Furthermore, the generation effect was not significant, and the solution selection did not differ between young and middle‐aged adults. 相似文献
999.
1000.
MA Lin 《Frontiers of Philosophy in China》2020,15(2):242
This paper traces the genealogy of reversibility, chiasma, and chiasme in Merleau-Ponty’s writings and offers a new characterisation of his later ontology in terms of a multi-layered chiasme-focused topology informed by subtle differences and interconnections among these notions. We need to grasp the significance of reversibility not only in terms of constant recoil and impossible overlap but also of its situatedness in the crisscrossing between Dasein and things, and between the inside/invisible and the outside/visible. “Chiasma” was initially introduced as a reference to the intersection of perspectives. Merleau-Ponty deploys it to articulate macroscopic insights concerning the nature of philosophy and the interweaving connections between self, other, and the world. In comparison, “reversibility” is primarily used to describe the microscopic bond between touching-touched and perceiving-perceived. I argue that, as Merleau-Ponty’s ultimate choice of wording, “chiasme” incorporated the significance of both “reversibility” and “chiasma.” A chiasme-focused topology that retains the significance of all three of the terms would serve to better convey the import of Merleau-Ponty’s later ontology, which aims to dissolve and to re-configure our conceptions about being, body, self, and the other from within and from below. 相似文献