Comparison of brain mechanisms underlying the processing of Chinese characters and pseudo-characters: an event-related potential study

Most Chinese characters are composed of a semantic radical on the left and a phonetic radical on the right. The semantic radical provides the semantic information; the phonetic radical provides information concerning the pronunciation of the whole character. The pseudo‐characters in the study consisted of different sub‐lexical parts of real Chinese characters and consequently they also had the semantic radical and the phonetic radical. But they were not readable and had no actual meaning. In order to investigate the spatiotemporal cortical activation patterns underlying the orthographic, phonological and semantic processing of Chinese characters, we used event‐related brain potentials (ERPs) to explore the processing of Chinese characters and pseudo‐characters when 14 healthy Chinese college students viewed the characters passively. Results showed that both Chinese characters and pseudo‐characters elicited an evident negative potential peaking around 120 ms (N120), which appeared to reflect initial orthographic distinction and evaluation. Then, Chinese pseudo‐characters elicited a more positive ERP deflection (P220) than did Chinese characters 200–250 ms after onset of the stimuli. It was similar to the recognition potential (RP) and might reflect the integration processes of phonological and semantic processing on the basis of early orthographic information. Dipole source analysis of the difference wave (pseudo‐characters minus characters) indicated that a generator localized in the left temporal‐occipital junction contributed to this effect, which was possibly related to phonological and perceptual–semantic information integration. Between 350–450 ms, a greater negativity (N360) in pseudo‐characters as compared to characters was found over midline fronto‐central scalp regions. Dipole analysis localized the generator of N360 in the right parahippocampal cortex. Therefore, the N360 might be an N400 component and reflect the higher‐level semantic activation on the basis of orthographic, phonological and perceptual–semantic processing.     

Gradual growth versus shape invariance in perceptual decision making

A dominant theme in modeling human perceptual judgments is that sensory neural activity is summed or integrated until a critical bound is reached. Such models predict that, in general, the shape of response time distributions change across conditions, although in practice, this shape change may be subtle. An alternative view is that response time distributions are shape invariant across conditions or groups. Shape invariance is predicted by some race models in which the first of several parallel fibers to communicate the signal determines the response. We competitively assess a specific gradual growth model, the one-bound diffusion model, against a natural shape-invariant competitor: shape invariance in an inverse Gaussian distribution. Assessment of subtle shape change versus shape invariance of response time distributions is aided by a Bayesian approach that allows the pooling of information across multiple participants. We find, conditional on reasonable distributional assumptions, subtle shape changes in response time that are highly concordant with a simple diffusion gradual growth model and discordant with shape invariance.     

Thing, Value, Time, and Freedom: A Consideration of Some Key Concepts in Marx’s Philosophical System

Criticizing the misunderstanding and wrong explanation of Marx’s philosophical system made by recent Chinese textbooks on Marxist philosophy, the author argues that Marx’s philosophy has practical, economical-philosophical, and ontological dimensions and stresses on reconstructing Marx’s philosophical system through synthesizing the above three dimensions. This paper intends to set up a new outline of Marx’s philosophical system, in terms of the following four concepts—thing, value, time, and freedom. Translated by Tang Jie from Zhexue Yanjiu, 2004:11     

基于胜任特征的结构化面试初探

基于胜任特征的结构化面试是对传统结构化面试的优化,有很高的信度和效度。本文从基于胜任特征的结构化面试的内涵、特点、程序以及实施过程中需要注意的问题几个方面进行了深入探讨,对于改善结构化面试的测评功能和深化胜任特征的应用有一定价值。     

急性心肌梗死患者院前延误的影响因素

急性心肌梗死(AMI)患者的治疗关键在于早期诊断和及时开通闭塞的冠状动脉,患者在发病后能否及早到院接受再灌注治疗,对患者的治疗效果和预后有重要影响.院前延误时间(PDT)即为从患者出现症状至到达医院接受治疗的时间.AMI患者就医大多是延迟的,主要原因是患者不能决定自己的症状是否需要治疗,也就是患者决定就医时间延长.本研究目的是分析造成急性心肌梗死患者院前延误的相关影响因素,为患者赢得最佳治疗时间提供理论依据.     

国外护理硕士教育与临床实践效果的研究现状

通过文献分析法,一方面探讨美国、英国、日本、泰国护理硕士研究生的招收条件、培养目标与课程设置、综合评定考核方法等,了解国外护理硕士培养机制;另一方面分析国外护理硕士课程对临床护理的影响,以及毕业后从事临床护理的实践效果和临床工作中面临的挑战,以期为我国护理硕士教育的发展提供借鉴.     

腹腔镜在女性盆底修复术中的应用

随着社会老龄化的加剧,盆底功能障碍性疾病的发病率日益上升.之前热门的盆底重建术随着时间的推移,并发症相继出现.美国食品药品管理局(FDA)连续两次发布了关于经阴道网片的警告,使专家们认识到了问题的严重性.经过30余年的发展,腹腔镜技术已经被广泛地应用于各类妇科手术中.腹腔镜在女性盆底修复术中的应用重新得到了关注.自1991年腹腔镜技术首次应用于女性盆底修复手术中以来,国内外不断有新的腹腔镜下盆底修复术式的报道.现就各种腹腔镜下盆底修复手术做一综述.     

一种多级评分的广义认知诊断模型

认知诊断是近些年教育测量研究中的热点,大多数的认知诊断模型仅适用于0～1评分的情况.本文提出一种有多个潜变量多个滑动参数的多级评分认知诊断模型——GP-D1NA,只要由评分标准和知识状态能确定理想反应模式,就可以利用此方法进行认知诊断分析.在该方法中,我们给出项目滑动矩阵的概念,将被试的观测得分均看成由某个理想得分的滑动,并采用EM算法估计滑动矩阵.在模拟研究中,采用每掌握一个属性得1分的评分标准,结果表明线性型、收敛型、发散型、无结构型和独立型五种属性层级结构均有较高的判准率.