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961.
Nilam?RamEmail author Sy-Miin?Chow Ryan?P.?Bowles Lijuan?Wang Kevin?Grimm Frank?Fujita John?R.?Nesselroade 《Psychometrika》2005,70(4):773-790
Weekly cycles in emotion were examined by combining item response modeling and spectral analysis approaches in an analysis
of 179 college students' reports of daily emotions experienced over 7 weeks. We addressed the measurement of emotion using
an item response model. Spectral analysis and multilevel sinusoidal models were used to identify interindividual differences
in intraindividual cyclic change. Simulations and incomplete data designs were used to examine how well this combination of
analysis techniques might work when applied to other practical data problems. Empirically, we found systematic individual
differences in the extent to which individuals' emotions follow a weekly cycle, and in how such cycles are exhibited. Weekly
cycles accounted for very little variance in day to day emotions at the individual level. Analytically, we illustrate how
measurement, change, and interindividual difference models from different traditions may be combined in a practical manner
to describe some of the complexities of human behavior.
The authors gratefully acknowledge the support provided by grant T32 AG20500 from the National Institute on Aging in the preparation
of this article. Special thanks to those at the Institute for Developmental and Health Research Methodology at the University
of Virginia and to Paul De Boeck and the reviewers for helpful comments on earlier versions of this work. 相似文献
962.
<维摩诘经>是印度早期大乘佛教的重要经典,在南北朝和隋唐时期广为流传,在佛教般若思想的发展中占有重要地位.该经蕴含着丰富的净土思想,明确提出了"心净则佛土净"这一著名命题.本文从菩萨取净土之目的与方法的角度,认为<维摩诘经>中菩萨取净土的目的是度化调伏众生,此即为"众生之类是菩萨佛土"的内含意蕴,还阐述分析了建立净佛国土之净土行和"心净则佛土净"思想. 相似文献
963.
Two types of mechanisms have dominated theoretical accounts of efficient visual search. The first are bottom-up processes related to the characteristics of retinotopic feature maps. The second are top-down mechanisms related to feature selection. To expose the potential involvement of other mechanisms, we introduce a new search paradigm whereby a target is defined only in a context-dependent manner by multiple conjunctions of feature dimensions. Because targets in a multiconjunction task cannot be distinguished from distractors either by bottom-up guidance or top-down guidance, current theories of visual search predict inefficient search. While inefficient search does occur for the multiple conjunctions of orientation with color or luminance, we find efficient search for multiple conjunctions of luminance/size, luminance/shape, and luminance/topology. We also show that repeated presentations of either targets or a set of distractors result in much faster performance and that bottom-up feature extraction and top-down selection cannot account for efficient search on their own. In light of this, we discuss the possible role of perceptual organization in visual search. Furthermore, multiconjunction search could provide a new method for investigating perceptual grouping in visual search. 相似文献
964.
Activation of group II metabotropic glutamate receptors induces depotentiation in amygdala slices and reduces fear-potentiated startle in rats 总被引:3,自引:0,他引:3 下载免费PDF全文
Lin CH Lee CC Huang YC Wang SJ Gean PW 《Learning & memory (Cold Spring Harbor, N.Y.)》2005,12(2):130-137
There is a close correlation between long-term potentiation (LTP) in the synapses of lateral amygdala (LA) and fear conditioning in animals. We predict that reversal of LTP (depotentiation) in this area of the brain may ameliorate conditioned fear. Activation of group II metabotropic glutamate receptors (mGluR II) with DCG-IV induces depotentiation in the LA. The induction of depotentiation is independent of NMDA receptors, L-type Ca++ channels, and calcineurin activity, but requires presynaptic activity and extracellular Ca++. (2S,2'R,3'R)-2-(2',3'-dicarboxycyclopropyl)glycine (DCG-IV) depotentiation is accompanied by a decrease in the frequency but not the amplitude of miniature excitatory post-synaptic currents (mEPSCs) and could be mimicked by endogenously released glutamate. DCG-IV inhibited the release of glutamate evoked by 4-AP but not that evoked by ionomycin, suggesting that the effect of DCG-IV is not mediated by an action downstream of Ca++ entry. Intra-amygdala infusion of mGluR II agonist blocks the consolidation of fear memory measured with fear-potentiated startle. Taken together, the present results characterize the properties of DCG-IV depotentiation and reveal a close parallel between depotentiation in the amygdala slice and the reduction of conditioned fear in animals. 相似文献
965.
Improving measurement precision of test batteries using multidimensional item response models 总被引:1,自引:0,他引:1
A conventional way to analyze item responses in multiple tests is to apply unidimensional item response models separately, one test at a time. This unidimensional approach, which ignores the correlations between latent traits, yields imprecise measures when tests are short. To resolve this problem, one can use multidimensional item response models that use correlations between latent traits to improve measurement precision of individual latent traits. The improvements are demonstrated using 2 empirical examples. It appears that the multidimensional approach improves measurement precision substantially, especially when tests are short and the number of tests is large. To achieve the same measurement precision, the multidimensional approach needs less than half of the comparable items required for the unidimensional approach. 相似文献
966.
The authors examined clockwise and counterclockwise wheel-rotation responses to high- or low-pitched tones presented in participants' (N = 96, Experiment 1; N = 48, Experiment 2; N = 48, Experiment 3) left and right ears. In Experiment 1, a Simon effect (fastest responding when tone location and direction of wheel turn corresponded) was obtained when participants' hands were at the top or middle of the wheel but not at the bottom. With the bottom hand placement, a Simon effect was induced by instructions emphasizing hand movements but not by instructions emphasizing wheel movements (Experiment 2), and by a visual cursor controlled by the wheel but not one triggered by the response (Experiment 3). The results of the experiments showed that the nature of the task and the instructed action goal influence the direction of the Simon effect. 相似文献
967.
We examined clinically depressed (CD; n = 16), previously depressed (PD; n = 19) and never depressed (ND; n = 18) individuals on 13 theoretically selected Rorschach (Exner, 1993; Rorschach, 1942) variables and on the Beck Depression Inventory (BDI; Beck, Rush, Shaw, & Emery, 1979). The group assignment was made according to the criteria of Diagnostic and Statistical Manual of Mental Disorders (4th ed.; American Psychiatric Association, 1994). We tested 2 contradictory models for depressive vulnerability, Beck's (Clark & Beck, 1999) and Miranda and Persons's (1988; Persons & Miranda, 1992), in a planned comparison design with focused contrasts. The CDs significantly contrasted the combined group of NDs and the PDs in a pathological direction on 8 of the 13 Rorschach variables and on the BDI. However, the combined group of CDs and PDs also significantly contrasted the NDs in a pathological direction on 3 of these Rorschach variables and on the BDI. In addition, logistic regression analyses indicated that Rorschach indexes significantly improved the prediction of major depression above and beyond that achieved by the BDI. The findings show that the Rorschach method was able to identify (a) cognitive and aggressive disturbances that are present in individuals who are actively depressed but not in individuals who have been depressed in the past or never been depressed and (b) affective and coping disturbances that are present in depressed individuals and to some degree in PD individuals but not in individuals who have not experienced depression. We discuss the scanty evidence of psychological disturbances in PD individuals, as measured with the Rorschach, in relation to the mood-state dependent hypothesis of Miranda and Persons (1988; Persons & Miranda, 1992). 相似文献
968.
外表真实区别、表征变化和错误信念的任务分析 总被引:4,自引:0,他引:4
自20世纪80年代以来,“心理理论”已成为发展心理学的研究热点和最活跃、最多产的领域。为了分析和比较“心理理论”的实验任务,该研究以济南市3所幼儿园中的233名3—6岁儿童为有效被试。进行了“意外转移。和“欺骗外表”两种心理理论实验任务。得出如下主要结论:(1)意外转移任务中内隐错误信念显著难于标准错误信念,易化错误信念与标准错误信念的难度不存在显著差异。(2)欺骗外表任务中外表真实区别难度显著低于表征变化和错误信念。(3)意外转移任务的错误信念显著难于欺骗外表任务的错误信念。 相似文献
969.
该文用配对比较方法,从夫调谐波的数量对谐波筛的影响(实验一)、失调谐波的位置(实验二)以及谐波相位与其失调幅度之间的相互作用(实验三)等三个方面对失调谐波的分离机制进行探讨。研究结果表明:(1)多个谐波同时失调时其失调效应要比单个谐波强,即谐波失调存在累积效应;(2)谐波次数不同,其失调效应也存在差异,这种差异与谐波和共振峰之间的距离有关,谐波越靠近共振峰,其失调效应越明显,但对由等振幅的谐波系列构成的复合声而言,高次谐波的失调效应比低次谐波弱;(3)谐波相位对其失调效应产生间接影响,这种影响与谐波的起始振幅有关,当相位为π/2和3π/2时,失调效应更加明显。 相似文献
970.
王跃生 《医学与哲学(人文社会医学版)》1999,20(9):10-11
伪科学现象的泛滥给社会造成极大危害。而各种伪科学的兴起均有众多信陡做为基础。是什么心理状态使许多人陷入其中,从俯仰危机、文化素质低下、精神病态心理、获益心理、利欲驱动、显示与控制欲等诸方面对伪科学信陡进行心理分析,以利于其迷知返,铲除伪科学现象,净化社会环境。 相似文献