单个汉字结尾笔画事件相关电位N400的研究

目的通过分别研究单个简单汉字结尾笔画匹配与非匹配以及单个复杂汉字结尾笔画联想正确与联想错误事件相关电位N400的变化，探讨正常人单个汉字结尾笔画事件相关电位N400的特征。方法对10名23岁．26岁右利手健康受试者，分别进行单个简单汉字结尾笔画匹配与非匹配的ERP实验，以及单个复杂汉字联想正确与联想错误的ERP实验。结果无论是单个简单汉字结尾笔画非匹配时还是单个复杂汉字联想错误时均可以诱发出波形较宽大而且走向明显向负的N400，其波幅均在中央顶部偏高，但两实验的诱发电位也有明显的差别。结论单个简单汉字结尾笔画匹配与非匹配的N400以及单个复杂汉字结尾笔画联想正确与联想错误的N400与字词认知中的语义密切相关，而且作为象形文字的汉字与作为拼音文字的西文在认知过程中存在差异。     

过度使用互联网对听觉事件相关电位的影响

当前,青少年上网成瘾已经成为一个严重社会问题.我们通过对9例过度使用互联网与9例较少使用互联网的受试者的听觉事件相关电位的对比研究,发现过度使用互联网会对人的听觉事件相关电位产生明显的影响.这提示过度地使用互联网会对大脑的认知功能产生一定的影响.     

事件相关脑电位研究新进展——N400

一、概述 进入二十一世纪以来，我国政府在精神卫生方面有了一系列大动作。2001年召开第三次全国精神卫生工作会议。2002年出台《中国精神卫生工作规划》。2004年由国务院办公厅颁发了多部委联合签署的《关于进一步加强精神卫生工作的指导意见》。这些大事预示我国精神卫生工作已步入一个新的发展时期。卫生部，     

事件相关电位及其亚成分

一、概述 人类脑电活动研究的发展,在20世纪中经过了三个主要阶段。第一阶段自七十年前Berger发现了人类脑电波并发表了他的论文开始。第二阶段从1949年Dawson的工作开始,他记录并分析了人的脑诱发电位。第三阶段始于1964年,研究者开始应用可供利用的各种先进技术     

中学生互联网过度使用团体心理治疗的对照研究

目的:探讨团体心理治疗在中学生互联网过度使用(IOU)治疗中的效果。方法:对长沙市2所重点中学和2所普通中学初一、初二、高一、高二年级的学生,采用Beard修订的Young的诊断问卷(YDQ)进行筛查,对筛查阳性者进行诊断性访谈,确定IOU学生64例。选择其中1所重点中学和1所普通中学的29例IOU学生作为实验组,采用认知行为取向的团体心理治疗对其进行干预,另外两所中学的35例IOU学生作为对照组。采用YDQ、陈淑惠的网络成瘾量表(CIAS)、儿童焦虑性情绪障碍筛查表(SCARED)、长处和困难问卷(SDQ)于治疗前后施测。结果:治疗前两组学生的YDQ、CIAS评分差异无统计学意义。治疗后,实验组SCARD总分及各因子分、SDQ的情绪症状因子分均较治疗前明显下降(如焦虑总分19.4±14.8/33.3±18.5,t=2.11～2.99,P<0.05～0.01;情绪症状:2.6±1.7/3.9±2.5,t=2.21,P=0.032)。实验组治疗后的YDQ、CIAS评分均较治疗前明显下降(3.0±2.6/7.1±0.8,45.2±18.4/67.5±14.9,t=-8.083、-4.383,均P=0.000)。实验组显效率为57.69%,总有效率达76.92%。治疗后实验组YDQ、CIAS评分均低于对照组(3.0±2.6/5.6±2.1,45.2±18.4/66.7±12.2,t=4.16,t=5.16,均P=0.000)。结论:认知行为取向的团体心理治疗能显著改善IOU中学生对网络的过度使用。     

中学生互联网过度使用与冲动的关系

目前对互联网过度使用（Intemet Overuse，IOU）的概念还没有形成统一认识，一些学者认为是一种冲动控制障碍或至少与冲动有关，本研究对此进行探讨。     

中学生互联网过度使用与时间管理倾向的关系

目的:探讨中学生互联网过度使用与时间管理倾向的关系。方法:采用网络成瘾诊断问卷和青少年时间管理倾向量表对2620名中学生施测。结果:诊断为互联网过度使用者有64名,占2·4%;互联网过度使用组在时间管理倾向总分低于对照组(129·7±25·3/150·0±28·5,t=4·27,P<0·01),各因子得分也较对照低(如时间效能感29·5±6·5/35·2±7·1,其他因子相差也在项目满分的10%左右,这些差异均有统计学意义);Logistic回归分析发现时间管理行为效能作为保护因素对互联网过度使用有影响(OR=0·78,95%CI=0·69~0·88)。结论:互联网过度使用学生的时间管理水平较差,可能是造成互联网过度使用的原因之一。     

刺激间隔对事件相关电位N270的影响

目的：观察刺激间隔对颜色冲突诱发的事件相关电位Ｎ２７０的影响。方法：采用美国Ｎｅｕｒｏｓｃａｎ脑电诱发电位工作站,对１５名健康受试做刺激匹配的事件相关电位研究,要求受试判断前后两个刺激的颜色是否相同,并作出按键反应,每对刺激以不同的刺激间隔呈现（ｏｍｓ,１５０ｍｓ,５００ｍｓ,１０００ｍｓ）,结果;５００ｍｓ和１０００ｍｓ状态,当一对刺激颜色不同时,在第二个刺激出现后约２７０ｍｓ处从头皮可记录     

中西文N400的研究现状简述(1)

1980年美国学者Kutas和Sillyard首先报道在一项语句阅读任务中可由语义不匹配的结尾词引出一个负性电位，因其潜伏期在400ms左右，遂称之为N400。N400是事件相关电位(ERP)的内源性成份之一，可通过各种语言操作任务诱发，主要反映语言认知的过程。Friederici等(1997)研究表明，     

自我概念、心理健康与中学生互联网过度使用倾向的关系研究

目的:研究中学生互联网过度使用倾向(IOT)与自我概念、心理健康的关系。方法:采用网络成瘾量表、田纳西自我概念量表、症状自评量表对781名中学生进行了调查。结果:①IOT在中学生中的发生率为9.6%;IOT组的自我批评因子得分显著高于对照组,自我概念总分及其他各因子显著低于对照组(P0.01或P0.05)。②除恐怖因子外,IOT组在心理症状各项因子得分以及总均分上都显著高于对照组(P0.001或P0.01)。③自我概念除了可以直接影响IOT外,还可通过心理健康这一间接途径对其进行影响(中介效应占总效应的34.91%)。结论:对IOT的预防和干预既要着力于其心理困扰的解决,也要注重其积极自我概念的培养。     

语言认知事件相关电位N400的研究进展

N400作为事件相关电位的一个内源性成分，反映了大脑语言认知的加工过程，越来越受到广泛关注。本文回顾了事件相关电位N400的发现、特点、起源和引出方法。总结近几年国内外有关语言认知N400研究内容及热点，探讨了事件相关电位N400在语言认知研究领域的应用前景。     

注意状态对事件相关电位的影响研究

目的：研究不同注意状态下事件相关电位的变化特点。方法：智能正常年轻人18例，采用oddball模式，非靶刺激为80％的750Hz低频短音，靶刺激为20％的2000Hz高频短音。利用Nicolet Pathfinder Ⅱ型诱发电位仪，记录主动分辨靶刺激时，计数／不计数状态下事件相关电位各波潜伏期和P3波幅的变化。结果：与计数靶刺激时比，在不计数时P3波幅显著降低（P＜0．01），P3潜伏期及其余各波潜伏期变化无显著性意义。结论：P300波幅与注意密切相关，P3潜伏期不易受被试注意力的影响，是一个稳定的测量认知功能的指标。     

The N400 as a function of the level of processing

In a semantic priming paradigm, the effects of different levels of processing on the N400 were assessed by changing the task demands. In the lexical decision task, subjects had to discriminate between words and nonwords and in the physical task, subjects had to discriminate between uppercase and lowercase letters. The proportion of related versus unrelated word pairs differed between conditions. A lexicality test on reaction times demonstrated that the physical task was performed nonlexically. Moreover, a semantic priming reaction time effect was obtained only in the lexical decision task. The level of processing clearly affected the event-related potentials. An N400 priming effect was only observed in the lexical decision task. In contrast, in the physical task a P300 effect was observed for either related or unrelated targets, depending on their frequency of occurrence. Taken together, the results indicate that an N400 priming effect is only evoked when the task performance induces the semantic aspects of words to become part of an episodic trace of the stimulus event.     

The N400 and the P300 are not all that independent

This study assessed whether two ERP components that are elicited by unexpected events interact. The conditions that are known to elicit the N400 and the P300 ERP components were applied separately and in combination to terminal-words in sentences. Each sentence ended with a terminal-word that was highly expected, semantically unexpected, physically deviant, or both semantically unexpected and physically deviant. In addition, we varied the level of semantic relatedness between the unexpected terminal-words and the expected exemplars. Physically deviant words elicited a P300, whereas semantically unexpected words elicited an N400, whose amplitude was sensitive to the level of semantic relatedness. Words that were both semantically unexpected and physically deviant elicited both an N400 with enhanced amplitude, and a P300 with reduced amplitude. These results suggest an interaction between the processes manifested by the two components.     

Event-Related Potentials Elicited by Deviant Endings to Melodies

Event-related potentials were recorded from scalp electrodes while subjects listened to well-known melodies. The melodies ended either with the expected note or with a different note. This design was a nonlinguistic analogue of the design used by Kutas and Hillyard (1980b), who first reported that anomalous terminal words in sentences elicited N400 potentials. However, Besson and Macar (1987) reported that deviant terminal notes in melodies did not elicit N400 potentials. In the present study, additional time was allowed for expectations to develop for the terminal note. Deviant terminal notes did not elicit N400s. In both studies, however, the deviant notes elicited P300-like waves. This outcome raised the possibility that N400 might have been masked by the positive potential. In a second condition in which P300 amplitude was minimized, N400s were again not evident. These results thus illustrate two additional situations in which nonlinguistic stimuli that deviated from a sequential pattern failed to elicit N400 potentials.     

P300, N400, aerobic fitness, and maximal aerobic exercise

Electrophysiological effects of aerobic fitness and maximal aerobic exercise were investigated by comparing P300 and N400 before and after a maximal cycling test. Event-related potentials (ERPs) were obtained from 20 students divided into two matched groups defined by their aerobic fitness level (cyclists vs. sedentary subjects). The session of postexercise ERPs was performed immediately after body temperature and heart rate returned to preexercise values. At rest, no significant differences were observed in ERP parameters between cyclists and sedentary subjects. This finding argued against the hypothesis that ERP modifications may be directly assumed by aerobic fitness level. The postexercise session of ERPs showed a significant P300 amplitude increase and a significant P300 latency decrease in all subjects. Similarly, N400 effect increased significantly after the maximal exercise in all subjects. ERP changes were of the same magnitude in the two groups. The present study argues for a general arousing effect of maximal aerobic exercise, independently of the aerobic fitness level.     

Event-related potential correlates of the collective self-relevant effect

The present study investigated the electrophysiological correlates of the psychological processing of the collective self-relevant stimulus using a three-stimulus oddball paradigm. The results showed that P300 amplitude elicited by the collective self-relevant stimulus was larger than those elicited by familiar and unfamiliar stimuli. In addition, N250 and P300 amplitudes elicited by subjects’ own names were larger than those elicited by other name stimuli. In terms of lateralization of P300, the collective self-relevant effect was largest in the left region sites and the individual self-relevant effect was largest in the right region sites. Therefore, the present study extended previous findings by showing that the collective self, similar to the famous individual self, was psychologically important to humans.