事件相关电位概念及成分笔记.docx

事件相关电位发展：1929HansBerger:EEG;1935-1936PaulineandHallowellDavis单试次ERP(SINGLETRAIL)1962GalamobosandSheatz计算机平均ERP1964GreyWalter第一个认知ERP成分CNV(contingentnegativevariation关联负变化)1965SuttonxBrarenxZUnbin和JOhn,p3基本概念：ERP:事彳蝴关电位本来叫诱发电位(evokedpotential,Eps)Event-relatedpotentialsarevoltagefluctuationsintheelectroencephalogram(EEG)thataretime-lockedtointernalorexternalevents(e.g.zstimuli,responses,decisions)脑干诱发反应(BERfbrainstemevokedresponse):又叫听觉脑干反应(ABRs),是由咯哒声那样的听刺激，在刺激后的前10秒，所诱发的电压很小的ERPse视诱发电位(VEP,visualevokedpotentials/VER,visualevokedresponse)诱发反应电位(evokedresponsepotentials)起源与神经元有关的电活动：1、动作电位(离散的电压尖峰，从轴突始到轴突末，释放神经递质)；2、突触后电位(神经递质结合于突触后细胞膜受体时产生电压：神经递质引起例子通道的开放与闭合，从而导致跨细胞膜电位的梯度变化。）单个神经元的突触后电位/动作电位同时记录许多神经元一综合的突触后电位或动作电位神经元群(Iargepopulationofneurons)进行动作电位记录叫做"多细胞"记录("multi-unitrecordings);从神经元集群(Iargegroupsofneurons)进行的突触后电位记录，叫做“局部场电位”记录(mlocalfieldpotential"recordings)Inalmostallcases,ERPsoriginatefromPOStryOSPtiCPOtentiap(PSPS)incorticalpyramidalcells,arisingasaconsequenceoftheflowofionsacrossthecellmembraneinresponsetoneurotransmittersbindingwithreceptors.WhenPSPsoccursimultaneouslyinsimilarlyorientedneurons,theresultingfieldpotentialssummateandthevoltagecanbedetectedinstantaneouslyonthescalp.Thus,ERPsprovideadirect,millisecond-resolutionmeasureofneurotransmission-relatedneuralactivity.偶极子：突出前末端释放兴奋性神经递质,引起正离子流入突触后神经元，从而在这个神经元的细胞体以外区域产生膜外负电位，同时,为了形成一个环路，电流又会从细胞体与基数突流出，造成这个区域带正电。顶树突的浮点与细胞体的正电就形成了一个小偶极子。简单的说，一个偶极子就是小距离隔开的一堆正、负电位。如果所有的神经元都有相似朝向，接受同类型的输入，就可能在头皮伤进行测量，这种情况最可能出现于皮层椎体细胞。很多偶极子的累加基本等效于对这些偶极子进行朝向平均得到的单个偶极子，这种平均偶极子叫做等效电流偶极子（ECD,equivalentcurrentdipole）（这要这些偶极子的朝向，相互差异大于90。，他们就会在某种程度相互抵消，达到180。就会完全膈肖这就是为什么小脑蒲肯野氏细胞排列整齐，垂直朝向皮层表面，但由于皮层便面高度皱若，所以很难或者不可能记录到小脑电活动.）容积传导：当大脑这样的传导介质里存在一个偶极子时，电流就会通过介质传导，直到表面J电活动倾向于走最小阻抗的通路，因此，EPRs在遭遇到高阻抗的卢页骨时，倾向于向侧面扩散。这个导致了不能准确地获得ERP起源的真实位置。但是电是仪接近光速传播的，我们所记录的电位反应了同一瞬间脑内所发生的事情。用磁场记录代替电位记录就可以很大程度上避免因高阻抗颅骨所引起的电位污染。且L残生ERPS,ERPS偶极子附近就会产生磁场。2、磁场可以穿透露骨，且不因颅骨而模糊或受污染,所以磁场记录可以具有比电位记录更高的空间分辨率。一MEG（脑磁图）/ERMF（event-relatedmagneticfield）ERP成分介绍：视觉的感觉反应：Cl头后部的中线电极位置，极性变化，来自Vl区，在矩状裂周围（负责编码下视野信息的Vl区位于距状裂伤员，而负责编码上视野信息位于距状裂下缘。）通过上视野刺激产出负的的Cl的波。刺激后40-60ms出现，80-100ms达到峰值。高敏感于对比度、空间频率等刺激参数。Pl峰值在100-130ms,见于两侧枕区，会与Cl波重叠。fMRI确定Pl波早期起源于背侧外纹状皮层（枕中回），晚期起源主要在腹侧梭状回。也敏感于刺激参数的变化，以及空间注意的指向，以及被试的唤醒状态。NI多个子成分。子成分1,100-15OmS头前部电极；子成分2,150-200ms,顶区皮层，子成分3.150-200ms,两侧枕区皮层，辨别过程。】简介:Inneuroscience,theNlOOorNlisalarge,negative-goingevokedpotentialmeasuredbyelectroencephalography（itsequivalentinmagnetoencephalographyistheM100）;itpeaksinadultsbetween80and120millisecondsaftertheonsetofastimulus,anddistributedmostlyoverthefronto-centralregionofthescalp.Itiselicitedbyanyunpredictablestimulusintheabsenceoftaskdemands.ItisoftenreferredtowiththefollowingP200evokedpotentialasthe"N100-P200"or"Nl-P2"complex.Whilemostresearchfocusesonauditorystimuli,theN100alsooccursforvisual（SeeViSUalNLincludinganillustration）,olfactory,heat,pain,balance,respirationblocking,andSomatOSenSorystimuli。起源:TheauditoryNtoOisgeneratedbyanetworkofneuralpopulationsintheprimaryandassociationauditorycorticesinthesuperiortemporalgyrusinHeschl'sgyrus（赫氏回）andplanumtemporale（H平面）.Italsocouldbegeneratedinthefrontalandmotorareas.Theareageneratingitislargerintherighthemispherethantheleft.特征:TheNlOOispreattentive（前;iS）andinvolvedinperception（感知）becauseitsamplitudeisstronglydependentuponsuchthingsastherisetimeoftheonsetofasound,itsloudness,interstimulusintervalwithothersounds,andthecomparativefrequencyofasoundasitsamplitudeincreasesinproportiontohowmuchasounddiffersinfrequencyfromaprecedingone.NeuromagneticresearchhaslinkeditfurthertoperceptionbyfindingthattheauditorycortexhasatonotopicorganizationtoNlOO.14However,italsoshowsalinktoaperson'sarousal15andselectiveattention.16NlOOisdecreasedwhenapersoncontrolsthecreationofauditorystimulix17suchastheirownvoice.18P2头前部和中央皮层，靶刺激相对罕见时反应增强。与P3相比，P2靶特征特征简单，P3复杂。头后部，P2波常常与Nlsp2以及P3的重叠而难以区分。N170与顶正电位顶正电位(vertexpositivepotential)面孔刺激与非面孔刺激的差异波。150-20OmS,中央区的中线部位。N170,右半球，枕区两侧，面孔刺激和非面孔刺激。倒置面孔与正向面孑比激发更大更晚的N170o倒置效应和面孔特异性。P3家族P300刺激recording仪器:NexstmeXimiaEEG-systemwith60carbonelectrodescap(NexstmLtd.).Theimpedance:<10k.参考:placedontheforehead.【采样】Thesamplingratewas1450Hz.Allsignalswereamplifedwithagainof2000andfilteredwithahardware-basedbandpassfilterof0.1-350Hz.datawerelow-passfilteredandsegmentedintotrialsfrom-200mstoIOOOmsrelativetostimulusonset.Thedataweremanuallycheckeforanyartifacts,includingeyemovementsandblinks.Alltrialscontaminatedbyartifactswerediscardedfromfurtheranalysis.Datawerebaseline-correctedwitha100mswindowpriortothestimulusonset.ForcleanerERPtracesinfigures,datawerefilteredwithaIO-HzIowpassfilterinsteadofthe30Hzlow-passfilterusedfordataanalysis.Feedbackrelatednegativity(FRN)反馈Regardingfeedback-relatedERPs,aconsiderableamountofresearchreportsthatanERPcomponent,knownasthefeedbackrelatednegativity(FRN)1issensitivetofeedbackvalencesuchascorrectvs.incorrect,winvs.loss,betterorworse(Bismark,Hajcak,Whitworth,&Allen,2013;Gehring&Willoughby,2002;Holroyd&Coles,2002;MiltnerfBraun,&Coles,1997).FRNistypicallyobservedduringa200-350mstimewindowaftertheonsetoffeedbackstimuli.Inparticular,negativefeedbacksuchas"lose"elicitsanegativedeflectionofon-goingERPwaveformsthanpositivefeedbacksuchas"win",andthisFRNischaracterizedwithafronto-centralscalpdistribution(Gehring&Willoughby,2002;Miltneretal,1997;Walsh&Anderson,2012).Recentstudies,however,employedmoresophisticatedanalysestodecomposeERPsandfoundthatthisFRNwasdrivenbyapositivepotentialelicitedbyapositivefeedback,ratherthananegativepotentialelicitedbyanegativefeedback.Forexample,whenusingtemporalprincipalcomponentanalysestodecomposeoverlappingERPactivities(e.g.,FRN,P300,lateslowwaves),studiesshowedthatpositivefeedbacksuchasrewardcueselicitedpositiveERPswhilenegativefeedbackeliciteddampenedERPs(FotizWeinbergzDien,&Hajcakz2011;Proudfit,2015).Moreover,arecentsimultaneousEEG-fMRIrecordingstudyrevealedthattheERPselicitedbypositivefeedbackwaspositivelycorrelatedwithBOLDresponsesinreward-relatedbrainregionssuchastheventralstriatumandthemid-frontalbrainregions(Becker,Nitsch,Miltnerf&Straube,2014;seealsoCarlson,Foti,Mujica-Parodi,Harmon-Jones,&Hajcak,2011).N400TheN400isacomponentoftime-lockedEEGsignalsknownasevent-relatedpotentials(ERP).Itisanegative-goingdeflectionthatpeaksaround400millisecondspost-stimulusonset,althoughitcanextendfrom250-500ms,andistypicallymaximalovercentro-parietalelectrodesites.TheN400ispartofthenormalbrainresponsetowordsandothermeaningful(orpotentiallymeaningful)stimuli,includingvisualandauditorywords,signlanguagesigns,pictures,faces,environmentalsounds,andsmells