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731.
本研究设计了长度比较的实验,检查了5—11岁青海高原藏汉儿童长度概念的稳定性。研究结果表明:(1)5—11岁藏汉儿童长度概念稳定性是随年龄增长而发展的。藏汉儿童的成绩,10岁以前各年龄组均无显著差异,唯有11岁组差异显著,而其中了,9,10岁是几个值得注意的转折年龄。(2)儿童长度概念稳定性的发展大致有四个思惟水平,据此可以划分成几个年龄阶段,但各个阶段之间没有绝对的界限。儿童长度概念稳定性的发展,是各种认知成分相互交织、相互作用的结果。(3)概念“守恒”是一个复杂的变化过程。研究结果表明,直接认识与间接认识的矛盾关系是儿童认知结构形成和发展的重要因素。(4)不同文化背景和教育条件对藏汉儿童长度概念稳定性的发展有一定影响。  相似文献   
732.
恒河猴在繁殖笼内的等级结构   总被引:7,自引:0,他引:7  
有关非人灵长类社群结构的问题,国外已多有研究。许多学者认为无论在野外,或是在捕后(笼养)条件下进行观察都发现只要有几只动物在一起,形成一个群,那末群内的个体之间必然形成等级关系,而这种等级关系是线性排列的。换句话说,如果一群有A、B、C、D、E五只动物的话,它们的等级关系就是这样排列的:A>B>C>D>E。  相似文献   
733.
气功对老年人性格的影响   总被引:1,自引:0,他引:1  
用艾森克人格问卷和A型行为类型问卷对122名练气功二年以上60岁以上的老年人及90名60岁以上从未练过气功的正常老人进行了测查。发现气功组神经质得分显著低于对照组。A型行为类型者气功组虽稍低于对照组,但无显著差异。练气功5年以上者A型行为类型得分显著低于练气功2—4年的。上述结果表明气功可能对改善老年人性格中的神经质维度有作用;气功可能会改变A型行为类型,但练功时间至少需5年以上才可能发生改变。  相似文献   
734.
采用程序标准化的婴儿迂回行为测验,探讨了244名8─11个月婴儿的迂回行为发展特点及学习能力。结果表明:(1)8─11个月婴儿的迂回行为水平表现出随婴儿月龄的增长而提高的趋势。(2)8─11个月的婴儿具有从反复尝试中学会迂回行为的可能性,其中9、10个月婴儿的学习可能性较大,而8个月婴儿的学习可能性较小。(3)8──11个月婴儿的学习速度随月龄增大而提高  相似文献   
735.
This study examined some possible factors that were expected to influence choices of coping strategies. They were demographic variables (age, sex, marital status, education, and family income), personality traits (extroversion, neuroticism and locus of control), perceived life stress, and received social support. Five hundred and eighty one randomly selected community adults living in Kaohsiung city were interviewed and completed questionnaires measuring the above variables. Multivariate analyses had shown that: (a) higher income and education were related to more use of ‘Seeking social resources’ and ‘Planning & hoping’ coping; (b) higher extroversion was related to more use of ‘Seeking social resources’, ‘Planning & hoping’ and ‘Emotional suppression’ coping, whereas the last was also related to higher neuroticism; (c) people with higher internal locus of control favoured ‘Planning & hoping’, but not ‘Emotional suppression’ coping; (d) perceived life stress was not related to any use of coping behaviours; however, (e) more social support was related to more use of all kinds of coping behaviours. Implications of results were discussed in the context of stress and adaptation.  相似文献   
736.
猫中脑“怒叫中枢”的定位与传入连接   总被引:1,自引:0,他引:1  
路长林 《心理学报》1983,16(2):93-100
本实验观察了电刺激猫中脑“怒叫中枢”引起的心电、脑电、呼吸、血压及行为变化,确定了“怒叫中枢”的组织学部位,并用辣根过氧化物酶(HRP)逆行转运方法研究了“怒叫中枢”区域的传入连接。结果表明,猫中脑“怒叫中枢”位于中脑尾侧滑车神经核水平,外侧被盖的楔状下核内,其范围局限于约1×1×1.5mm。电刺激此区可引起怒叫反应,呼吸加快,血压升高,慢性实验动物还表现出攻击或逃避行为。辣根过氧化物酶逆行转运实验结果表明,此区主要接受同侧下丘脑外侧核、后核、背内侧核、中脑中央灰质外侧部及邻近被盖区的直接投射纤维,同时也接受部分来自前脑与情绪有关脑区的纤维投射。  相似文献   
737.
This report describes the application of a functional analysis to obsessions and compulsions. The approach emphasizes a search for the independent variables which maintain obsessive-compulsive behavior in the individual client: then therapeutic procedures are designed to counteract the specific maintaining variables. The application, and outcome, of this approach to two children and one adult is described.  相似文献   
738.
汉语辅音知觉结构初探   总被引:4,自引:0,他引:4  
语言作为人类特有的信号系统,随着科学技术的发展,它的交际工具的作用,日益提高和加强。首先,语言交际的范围已经大大扩大,“人机对话”已经在有限的领域里开始实现,这就超出了传统上语言只作为人与人之间的交际工具的范畴。其次,借助电话、电报  相似文献   
739.
In a first-order reversed-phi motion stimulus (Anstis, 1970), the black-white contrast of successive frames is reversed, and the direction of apparent motion may, under some conditions, appear to be reversed. It is demonstrated here that, for many classes of stimuli, this reversal is a mathematical property of the stimuli themselves, and the real problem is in perceiving forward motion, which involves the second- or third-order motion systems or both. Three classes of novel second-order reversed-phi stimuli (contrast, spatial frequency, and flicker modulation) that are invisible to first-order motion analysis were constructed. In these stimuli, the salient stimulus features move in the forward (feature displacement) direction, but the second-order motion energy model predicts motion in the reversed direction. In peripheral vision, for all stimulus types and all temporal frequencies, all the observers saw only the reversed-phi direction of motion. In central vision, the observers also perceived reversed motion at temporal frequencies above about 4 Hz, but they perceived movement in the forward direction at lower temporal frequencies. Since all of these stimuli are invisible to first-order motion, these results indicate that the second-order reversed-phi stimuli activate two subsequent competing motion mechanisms, both of which involve an initial stage of texture grabbing (spatiotemporal filtering, followed by fullwave rectification). The second-order motion system then applies a Reichardt detector (or equivalently, motion energy analysis) directly to this signal and arrives at the reversed-phi direction. The third-order system marks the location of features that differ from the background (the figure) in a salience map and computes motion in the forward direction from the changes in the spatiotemporal location of these marks. The second-order system's report of reversed movement dominates in peripheral vision and in central vision at higher temporal frequencies, because it has better spatial and temporal resolution than the third-order system, which has a cutoff frequency of 3-4 Hz (Lu & Sperling, 1995b). In central vision, below 3-4 Hz, the third-order system's report of resolvable forward movement of something salient (the figure) dominates the second-order system's report of texture contrast movement.  相似文献   
740.
Although recent studies indicate that brain-derived neurotrophic factor (BDNF) plays an important role in hippocampal synaptic plasticity, the underlying signaling mechanisms remain largely unknown. Here, we have characterized the signaling events that mediate the BDNF modulation of high-frequency synaptic transmission. Mitogen-associated protein kinase (MAPK), phosphotidylinositol-3 kinase (PI3K), and phospholipase C-γ (PLC-γ) are the three signaling pathways known to mediate neurotrophin signaling in other systems. In neonatal hippocampal slices, application of BDNF rapidly activated MAPK and PI3K but not PLC-γ. BDNF greatly attenuated synaptic fatigue at CA1 synapses induced by a train of high-frequency, tetanic stimulation (HFS). Inhibition of the MAPK and PI3K, but not PLC-γ, prevented the BDNF modulation of high-frequency synaptic transmission. Neurotrophin-3 (NT-3), a close relative of BDNF, did not activate MAPK or PI3K and had no effect on synaptic fatigue in the neonatal hippocampus. Neither forskolin, which activated MAPK but not PI3 kinase, nor ciliary neurotrophic factor (CNTF), which activated PI3K but not MAPK, affected HFS-induced synaptic fatigue. Treatment of the slices with forskolin together with CNTF still had no effect on synaptic fatigue. Thus, although the activation of MAPK and PI3K is required, the two together are not sufficient to mediate the BDNF effect. Inhibition of new protein synthesis by anisomycin or cycloheximide did not prevent the BDNF effect. These data suggest that BDNF modulation of high-frequency transmission is independent of protein synthesis but requires MAPK and PI3K and yet another signaling pathway to act together in the hippocampus.  相似文献   
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