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681.
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
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
682.
Luís Otávio de Seixas Queiroz Maria Aparecida Motta Maria Beatriz Barbosa Pinho Madi Dirceu Luís Sossai John J. Boren 《Behaviour research and therapy》1981,19(5):377-388
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
683.
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
684.
Signaling Mechanisms Mediating BDNF Modulation of Synaptic Plasticity in the Hippocampus 总被引:8,自引:0,他引:8 下载免费PDF全文
Wolfram A. Gottschalk Hao Jiang Nicole Tartaglia Linyin Feng Alexander Figurov Bai Lu 《Learning & memory (Cold Spring Harbor, N.Y.)》1999,6(3):243-256
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
685.
关于健康社会性格的跨文化研究 总被引:1,自引:0,他引:1
社会性格作为国民素质的重要组成,其健康程度将直接影响精神文明建设的成效。本研究发现,当代人健康社会性格体系由五个因素构成,分别是:进取心、道德感、安定感、领导性与家庭性,为进一步深入探究,本研究采用跨文化方式,将日韩、欧美的参照样本与当代中国人进行比较研究,发现性别与国别因素对于五个因素中的若干项具有显著性影响,体现出跨文化差异性。本研究对于成功塑造跨世纪中国人健康社会性格将具有积极的理论与实践意义。 相似文献
686.
The Walsh Family Resilience Questionnaire (WFRQ) is one of the most widely used and strong theory-based measurement tools of family resilience. This study aimed to develop and psychometrically test the Chinese version of the WFRQ (WFRQ-C). The WFRQ was translated following Brislin's translation model. Psychometric testing, combining classical theory test and item response theory, was conducted with a sample of 800 community adult residents. The Connor-Davidson resilience scale-10 (CD-RISC-10), Self-reported Family Happiness Scale (SFHS-1), and Family APGAR (Adaption, Partnership, Growth, Affection, Resolve) Scale (Family APGAR-5) were applied for convergent validity. Six items were deleted at the item analysis level. The minimum average partial test and a parallel analysis supported a three-factor structure, which was validated by confirmatory factor analysis. The three factors were named “Family belief system,” “Organization, communication and problem solving,” and “Utilization of external resources.” The WFRQ-C was significantly correlated with CD-RISC-10, SFHS-1, and Family APGAR-5, with r values ranged from 0.51 to 0.56. The Cronbach's α was 0.97 for the scale and 0.93, 0.95, and 0.72 for the three factors, respectively. The ICCs of 0.96 for the whole scale, and 0.95, 0.75, and 0.95 for the three factors, respectively. The mean score for the WFRQ-C was 97.00 ± 17.94, of which per capita monthly income and education level were predictors. The 26-item WFRQ-C is a stable, concise, and validated tool to measure family resilience. It is applicable for Chinese community adults in nonspecific stressful settings and has potential utility in the health care domain. 相似文献
687.
688.
定序变量在心理现象和心理数据中随处可见, 采用综合的定序变量回归分析模型可以对“镜像模式”和“漏斗模型”的心理现象做出合理的解释和预测。首先通过非参数检验对影响因素进行初步降维, 其次用Probit定序回归对降维后的影响因素贡献率进行判别, 从而进一步筛选具有显著性判断水平的有效指标, 最后用Logistic回归模型对某种特定的心理现象发生与否进行信息量足够大的解释和预测。大学毕业生工作生活质量满意度的预测对这种综合定序变量回归分析模型的实例拟合, 证实了综合定序变量回归分析模型在心理现象和心理数据分析中的应用价值。 相似文献
689.
节奏感知是人类独有的认知现象, 听觉在节奏加工中具有优势, 声音节奏可以更好地与肢体运动同步, 但视觉和触觉通道在节奏感知上也有着各自特点并存在广泛的交互作用。视觉通道的节奏感知较弱, 与听觉节奏同时呈现时会受到时间定位上的拉扯, 但通过加入运动信息和增强后天经验可以得到强化; 节奏刺激可以调节注意在时间上的分配使其同步化, 这种调节作用可以单通道或者跨通道地出现; 触动觉与听觉联系紧密, 人们可以通过听触通道的整合对节奏进行高级加工。 相似文献
690.
汉语词汇产生中的义、音信息提取时间进程的ERP研究 总被引:5,自引:0,他引:5
摘 要 运用事件相关电位(ERP)技术考查了在汉语词汇产生过程中,语义提取和语音提取的时间进程。在实验过程中,给被试呈现一张图片,要求他们在小声进行图片命名之前,先基于语义信息(图上画的是物体还是动物)或语音信息(如图片名称是以字母s还是以y开头)完成一个双重选择任务。在一种情况下,反应手(左手或右手按键)由语义信息决定,是否反应(GO/NOGO)由语音信息决定;在另一种情况下,反应手由语音信息决定,是否反应由语义信息决定。结果发现,当是否反应由语义信息(动物/物体)决定时,N200的潜伏期是307ms;当是否反应由语音信息(如中文名称以S/Y开头)决定时,N200的潜伏期是447ms;两者之间存在显著的差异,即由语义信息引起的N200的潜伏期早于由语音信息引起的N200的潜伏期。结果表明,在汉语词汇产生过程中,语义提取先于语音提取。 相似文献