个体神经质水平对情绪加工的影响 ——事件相关电位研究

采用事件相关电位方法探讨个体神经质水平对情绪加工的影响，测量并比较了神经质高水平个体和神经质低水平个体观看三类图片（积极、中性和消极）时的事件相关电位。结果发现，P120、N130、P230和N250成分的刺激效价主效应显著，积极、消极情绪刺激与中性刺激诱发的ERP差异最早开始于刺激呈现后的120ms左右。其次，在额叶和额中央部位的晚正电位上，神经质水平与刺激效价交互作用显著，神经质高分组与低分组对消极情绪刺激的反应有明显差异，而两组被试对积极、中性刺激的反应没有表现出差异。结果支持神经质与消极情绪相关，个体的神经质水平主要影响额叶和额中央叶的晚期负性情绪加工

An Event-Related Potential Study of Neuroticism Influences on Emotional Processing

Introduction A number of studies have investigated how brain activity is modulated by emotion.These studies found some important general emotion effects in event-related potentials(ERPs),such as negativity bias,early posterior negativity and late positive potential(LPP).However,it is not clear how time processing of emotion is influenced by individual differences,especially in negative emotion.According to Eysenck's theory,personality trait of neuroticism is strongly associated with negative emotion,which has been supported by many behavioral studies.The present study used ERP to explore how time processing of negative emotion is modulated by levels of neuroticism.Methods ERPs were recorded from 15 high and 15 low neurotic participants.These participants were selected from 292 college students based on their scores in neuroticism of Eysenck Personality Questionnaire-Revised,Short Scale for Chinese(EPQ-RSC).These participants were presented slides of International Affective Picture System(IAPS)posing 50 positive,50 neutral and 50 negative pictures,which were displayed for 1000ms and presented serially in sequences of six pictures.To ensure that the subjects were attending to the pictures,a valence categorization task was introduced.The ITI(inter-trial interval)varied between 1000ms and 2000ms.Electrophysiological data were collected from the scalp using a 37-channel system.These data were submitted to repeated-measure analysis of variance(ANOVA)with factors of stimuli valence(3 levels:positive,neutral,negative),neuroticism(2 levels:high,low),electrode site(8 levels:F3,Fz,F4,Fc3,Fcz,Fc4,T5,T6),and hemisphere(2 levels:left,right).Results The results showed that the components of P120,N130,P230 and N250 exhibited a main effect of stimuli valence,reflecting greater ERP mean amplitudes for positive and negative as compared to neutral content.The difference begins with 120ms after stimulus onset.Furthermore,the interaction of Neurotic level and Stimuli valence is significant for LPP mean amplitude over frontal and frontal-central leads(F(1,28)= 6.52,p<0.1).This effect indicated that high neurotic subjects,compared with low neurotic ones,exhibited smaller LPP to negative pictures,while they did not display differences in the response to positive and neutral pictures.Conclusions The early emotion effect about 120ms suggests that early cognitive processing can be influenced and modulated by emotion.The LPP effect supports the view that negative emotion processing of brain is modulated by levels of neuroticism,and the influence is mainly reflected on late processing of negative emotion at frontal and frontal-central sites.The decreased LPP amplitude in high neurotic subjects may be the result of greater habituation in sessions with a large number of trials.