面孔加工特异性的事件相关电位研究

采用事件相关电位方法,以面孔、汽车、鸟和椅子为刺激,在汽车搜索作业及分类判断作业两种条件下考察了N170面孔特异性效应。结果发现,面孔在两种条件下均引起明显不同于其余三类物体的N170。实验任务对汽车刺激有明显的影响,具体表现为：在搜索作业下,汽车N170有接近面孔N170的趋势,其波幅显著大于鸟、椅子N170的波幅;在分类作业中,则没有这种显著的差异。从而为证明存在面孔识别的特异性神经机制提供了证据。     

面孔审美加工的神经机制及个体差异

外显和内隐的面孔审美加工的脑成像研究表明,美的面孔比不美的面孔导致眶额皮层、伏隔核、杏仁核等奖赏脑区更大的激活。脑电研究则发现了与面孔审美加工有关的早期负波和晚期正成分。面孔审美加工有关的脑区活动也受到性别、生理周期等个体因素的调节。未来的研究需要比较美的面孔与其它奖赏刺激加工的神经机制,探讨面孔审美加工的不同阶段及时间进程,在面孔知觉的框架下形成合理的面孔审美加工的神经模型。     

卡通面孔分类与识别加工的ERP比较研究

通过ERP方法,考察卡通面孔分类（人和动物）的脑机制及其与卡通面孔识别（人与车）的差异。结果表明,分类任务中,动物面孔VPP潜伏期显著长于人,N170潜伏期主效应不显著、波幅半球效应显著,LPP波幅在顶叶和中央区最大;分类任务VPP和LPP波幅均显著大于识别。结论：卡通面孔分类比识别速度慢、强度大,消耗心理资源多。顶叶和中央区可能是执行分类任务的主要脑区,且加工人类面孔具有优势。面孔加工中结构编码和特征编码可能部分是并行的。     

面孔识别特异性本质的ERP研究

本研究记录了16名被试在完成有整体结构变化和局部特征变化的面孔/房屋图片的一致性判断时的脑内时程变化,以期对面孔识别的特异性本质进行探讨。结果显示,N170波幅和潜伏期的刺激类型主效应显著;面孔/房屋所诱发的N170成分在波幅和潜伏期上均不存在加工方式上的显著差异。晚期成分(300～700ms)上也得到类似的结果。这表明:面孔与房屋(非面孔)的加工在早期和晚期成分上都有差异性,体现出面孔的加工在早期视觉刺激的加工和晚期识别的加工上都具有特异性;晚期识别加工的脑电结果不支持\"面孔识别是整体的,结构的,而非面孔客体的识别是局部的,基于特征的\"加工观点。     

赢分与输分运动员面孔表情和身体姿势情绪的加工机制*

本研究采用中国运动员赢分和输分后的表情, 通过行为学和脑电技术比较面孔表情和身体姿势的加工机制。实验1探讨了赢分与输分面孔和身体的效价和强度, 实验2考察了图片的情绪类型(中性、快乐、悲伤、愤怒、恐惧、厌恶), 实验3采用脑电技术比较了赢分和输分情绪的神经机制。3个实验的行为结果表明, 相比面孔, 身体信息更能区分赢分和输分的效价, 而且身体姿势传递的情绪内容相对单一, 面孔表情传递的情绪内容相对复杂和多样化。脑电实验的结果表明, 身体的情绪信息能更早地被大脑识别, 表现在N170成分上, 面孔表情的情绪效应, 反映在EPN成分上。在加工的晚期, 面孔和身体条件下, 均观测到胜利比失败表情诱发了更大的LPP成分。结果表明, 大脑在多个阶段对身体姿势进行情绪评估与分类, 为行为上身体对效价的高区分性提供了证据。     

面孔加工的结构编码阶段异族效应的加工方式： ERPs研究

实验采用事件相关电位（ERPs）技术,以大学生为被试,运用非洲、欧洲、亚洲三个不同种族的面孔照片,探究异族效应与加工方式的关系。行为实验结果显示,被试对非洲面孔的反应时快于欧洲面孔,且两者均快于亚洲面孔。ERP研究结果显示,亚洲面孔的N170波幅显著小于非洲和欧洲面孔的波幅,后两者的N170波幅没有差异,而且亚洲面孔的倒置效应最大。研究结果说明相对于异族面孔,本族面孔更多地使用构型编码的加工方式,且N170成分表现出右半球优势。     

面孔生命性加工的时间进程：ERP研究

本研究采用事件相关电位技术,通过参数设计考察了大脑加工面孔生命性时的神经电活动动态进程。结果显示：非生命性面孔比生命性面孔在中央顶区诱发了更大的LPP波幅;生命性和非生命性面孔诱发的LPP波幅均显著大于中间等级（60%）面孔,提示随生命性信息增强,LPP波幅呈“U”型变化。P1和N170未表现出面孔类别差异。结果表明LPP是探测面孔生命性加工的有效成分,支持面孔生命性加工位于面孔加工的晚期阶段的观点。     

动态面孔和语音情绪信息的整合加工及神经生理机制

面孔、语音情绪信息的整合加工是社会交往的重要技能, 近年来逐渐引起心理学、神经科学研究的关注。当前研究较为系统地考察了双通道情绪信息整合加工的行为表现和影响因素, 也很好地回答了“何时整合”与“在哪里整合”两个认知神经科学关注的问题, 但对“面孔、语音情绪信息能否整合为一致情绪客体？双通道情绪信息在大脑中如何整合为一？”两个关键问题都还缺乏系统研究。因此, 本项目拟系统操纵面孔、语音刺激的情绪凸显度和任务要求, 引入动态面孔-语音刺激以增加外部效度, 综合运用行为和电生理技术, 从多角度挖掘数据, 特别是引入神经振荡(时频、相干)分析, 系统考察动态性面孔和语音情绪信息是否能整合成一致情绪客体, 并在神经振荡层面探明双通道情绪信息整合的机制。     

知觉负载对负性分心面孔的知觉加工和记忆的影响

本研究采用视觉搜索和意外再认记忆任务,结合事件相关电位技术,考察知觉负载对负性分心面孔的知觉加工和记忆的影响。在视觉搜索任务中,行为上恐惧分心面孔在高负载下干扰任务。ERP结果上,恐惧比中性分心面孔诱发更大的N170和N250;在低负载下恐惧比中性分心面孔诱发更大的N700,在高负载下没有差异。在意外再认记忆中,个体对低负载下的恐惧分心面孔表现出记忆。这些结果说明负性分心物在早期是自动化加工;晚期加工受知觉负载的调节,负载越低对负性分心物的过滤越少,存在对负性分心物的记忆偏向。     

面孔可信度加工的时间进程和影响因素

面孔可信度在表达和理解社会信号中起着关键作用。人们通过微妙的面部线索快速地判断他人的可信度, 从而帮助人们进行日常生活选择。研究者们对面孔可信度加工的时间进程有关的行为和ERP研究都进行了深入地探讨, 并探索了其毕生发展特点, 以及面孔情绪和面孔性别等因素对面孔可信度评估的影响。未来研究可以提高面孔可信度研究材料的生态效度, 进一步拓展青春期和成年晚期对面孔可信度评估的研究, 以及考虑背景信息对面孔可信度评估的影响。     

面孔类别识别的N170和VPP的时空特异性研究

对面孔刺激敏感的ERP成分N170,其特异性至今仍有争论。本研究记录正立脸、倒置脸、动物脸、马赛克脸及七类物体类别图片刺激的ERP,分析ERP成分的峰值和潜伏期。正立脸比倒置脸、动物脸所引出的N170的峰值和潜伏期都高和早。其他类别刺激引出N170,其潜伏期早于脸刺激,峰值低于脸刺激。正立脸和动物脸VPP潜伏期显著长于其他类别刺激,之间没有差异显著性。脸刺激与其他物体类别刺激相比,N170和VPP是其特异性的脑波成分。     

Domain specificity versus expertise: factors influencing distinct processing of faces

To explore face specificity in visual processing, we compared the role of task-associated strategies and expertise on the N170 event-related potential (ERP) component elicited by human faces with the ERPs elicited by cars, birds, items of furniture, and ape faces. In Experiment 1, participants performed a car monitoring task and an animacy decision task. In Experiment 2, participants monitored human faces while faces of apes were the distracters. Faces elicited an equally conspicuous N170, significantly larger than the ERPs elicited by non-face categories regardless of whether they were ignored or had an equal status with other categories (Experiment 1), or were the targets (in Experiment 2). In contrast, the negative component elicited by cars during the same time range was larger if they were targets than if they were not. Furthermore, unlike the posterior-temporal distribution of the N170, the negative component elicited by cars and its modulation by task were more conspicuous at occipital sites. Faces of apes elicited an N170 that was similar in amplitude to that elicited by the human face targets, albeit peaking 10 ms later. As our participants were not ape experts, this pattern indicates that the N170 is face-specific, but not specie-specific, i.e. it is elicited by particular face features regardless of expertise. Overall, these results demonstrate the domain specificity of the visual mechanism implicated in processing faces, a mechanism which is not influenced by either task or expertise. The processing of other objects is probably accomplished by a more general visual processor, which is sensitive to strategic manipulations and attention.     

人类面孔识别工作记忆的脑电位特征

采用事件相关电位(ERPs)技术探索延迟匹配任务范式下面孔识别工作记忆的脑电位特征。实验以面孔图片为刺激,在校大学生被试完成靶匹配工作记忆任务。结果发现,被试识别靶面孔及分心物面孔时均在枕颞区两侧诱发N170,且靶与分心物的N170振幅在相同电极上都没有显著差异,在颞区两侧的P7和P8上差异显著;无论靶面孔还是分心物面孔,工作记忆的 ERPs均产生了 P300成分。在分别追踪新靶和熟悉靶的工作记忆任务条件下,靶与分心物的ERPs波形在250 ms后出现分离,且靶刺激波幅均比分心物更正,新靶比熟悉靶更正。熟悉分心物与新分心物之间显示出250~650 ms的前额区旧/新效应,在晚期的450~650 ms时段,新工作记忆比旧工作记忆波幅更正。这些结果表明,面孔识别的N170效应可能反映的是面孔知觉的整体加工,且 N170的右半球优势具体为颞区的右侧优势;先前的面孔学习会影响工作记忆期间大脑对面孔的识别反应。     

中英文Stroop干扰效应的脑机制

以中国大学生为被试,采用事件相关电位对比研究中英文Stroop干扰效应的脑内时程动态变化。结果发现：两种文字材料都存在反应时的Stroop干扰效应,汉字的干扰效应明显强于英文;被试在完成不同文字材料的字词颜色命名任务时所诱发的ERP成分存在差异,具体为中文Stroop干扰效应表现为在350—550ms内,不一致条件比一致条件诱发一个更负的ERP成分（N450）,主要分布于额中部电极。英文Stroop干扰效应表现为不一致条件比一致条件在250—450ms内诱发一个更正的ERP成分（P300）,主要分布于左侧额顶叶;在450—550ms内诱发一个更负的ERP成分（N500）,主要分布于中后部。研究结果表明语言类型会影响Stroop干扰效应的脑内时程变化。     

Investigation of effects of face rotation on race processing: An ERPs study

Recent ERP research has indicated that the processing of faces of other races (OR) and same race (SR) as the perceiver differs at the perceptual level, more precisely for the N170 component. The purpose of the present study was to continue the investigation of the race-of-face processing across multiple orientations. Event-related brain potentials (ERPs) and performance were recorded when Caucasian participants were required to categorize by race Caucasian and African faces presented in eight different angles of orientation. Three main observations were made: (1) the face-sensitive N170 is modulated by the race of faces, being larger in response to OR compared to SR faces; (2) face rotation affected this component in the same pattern for both racial groups; (3) the N170-ORE progressively disappeared as the faces moved away from their canonical orientation at the right hemisphere only. Thus, the current findings suggest that configural/holisitic information is extracted from faces of both racial groups, but that upright OR faces require increased demands.     

Who Do You Love, Your Mother or Your Horse? An Event-Related Brain Potential Analysis of Tone Processing in Mandarin Chinese

In Mandarin Chinese, word meaning is partially determined by lexical tone (Wang, 1973). Previous studies suggest that lexical tone is processed as linguistic information and not as pure tonal information (Gandour, 1998; Van Lanker & Fromkin, 1973). The current study explored the online processing of lexical tones. Event-related potentials were obtained from 25 Mandarin speakers while they listened to normal and anomalous sentences containing one of three types of semantic anomalies created by manipulating the tone, the syllable, or both tone and syllable (double-anomaly) of sentence-final words. We hypothesized N400 effects elicited by all three types of anomalies and the largest by the double-anomaly. As expected, all three elicited N400 effects starting approximately 150 ms poststimulus and continuing until 1000 ms in some areas. Surprisingly, onset of the double-anomaly effect was approximately 50 ms later than the rest. Delayed detection of errors in this condition may be responsible for the apparent delay. Slight differences between syllable and tone conditions may be due to the relative timing of these acoustic cues.