失配性负波在阿尔茨海默病中的应用研究

目的:探讨阿尔茨海默病(AD)患者失配性负波(MMN)的特点。方法:应用美国NicoletSpirtit脑诱发电位仪,对34例AD患者和36名正常老人的MMN作了检测。结果:AD组波形不规则,MMN-Ⅰ型(延迟型)尤甚。与正常老人组比较,AD患者MMN潜伏期延迟(P<0.05),波幅降低(P<0.01)。结论:初步认为MMN是反映AD患者认知功能的一种脑电生理检测工具。     

认知性电位研究的新进展—失配性负波

关于经典认知性电位（cognitive evoked potential）的关联性负变（contingent negative varation，CNV）和P300已有介绍。现再介绍认知性电位领域的一项新指标—失配性负波（mismatch negativity，MMN）。     

首发与复发精神分裂症患者失配性负波MMN的对比研究

目的:探讨首发与复发精神分裂症患者前注意信息加工的电生理机制差异。方法:采用纯音Oddball诱发模式,对36例首发精神分裂症患者(首发组)、38例复发精神分裂症患者(复发组)进行事件相关电位MMN检查,测量MMN的潜伏期、波幅,并与33名健康被试的结果进行比较。结果:与对照组相比,首发组的MMN潜伏期差异不显著(t=1.06,P0.05),复发组的MMN潜伏期显著延迟(t=4.23,P0.05),首发和复发组的MMN波幅均显著降低(t=2.69,3.36;P0.05);与首发组相比,复发组的MMN潜伏期显著延迟、波幅显著降低(t=3.66,3.03;P0.05)。结论:首发与复发精神分裂症患者的前注意信息自动加工电生理机制均受损,患者的反复发作能加重其受损。提示MMN受损指标可能是精神分裂症患者复发的潜在生物学标记。     

产后与非产后抑郁症患者听感觉门控的对比

目的 探讨产后与非产后抑郁症患者听感觉门控P50的变化差异特征,以便为产后抑郁症提供易感性指标.方法 采用配对听觉条件(S1)、测试(S2)刺激范式,对30例产后抑郁症患者(产后组)、32例非产后抑郁症患者(非产后组)进行听觉诱发电位P50检测,测量P50的潜伏期、波幅,并与30例健康被试(对照组)进行比较.结果 ①与对照组相比,S1-P50,S2-P50潜伏期产后组差异不显著;非产后组潜伏期显著延迟(S1-P50,t=2.52,P＜0.05;S2-P50,t=2.68,P＜0.05);②与对照组相比,产后组S1-P50波幅显著降低(t=3.04,P＜0.05),S2-P50波幅差异不显著,非产后组S1-P50,S2-P50波幅均显著降低(t=3.46,2.44;P＜0.05);③对照组、产后组、非产后组S2/S1波幅比值依次显著升高(x2=4.22,P＜0.05).结论 产后与非产后抑郁症患者感觉门控抑制能力均有缺陷,产后抑郁患者的缺陷是间于健康与非产后抑郁症中的一种亚健康的状态性受损.     

难治性与一般性抑郁症患者冲突性负波的对比研究

目的 探讨难治性与一般抑郁症患者事件相关电位N270指标的变化差异.方法 对20例难治性抑郁症患者（难治组）、26例一般性抑郁症患者（非难治组）进行事件相关电位N270检查,与22名健康志愿者的结果进行比较.结果 与对照组相比,P3、P4、Cz3个电极上,难治组N270潜伏期显著延迟（t=4.24,4.65,5.12;P＜0.05）,波幅显著降低（t=3.63,3.82,4.17;P＜0.05）;非难治组N270潜伏期差异不显著,波幅显著降低（t=2.56,2.62,3.02;P ＜0.05）.与非难治组相比,难治组N270潜伏期显著延迟（=3.62,3.22,4.12;P＜0.05）,波幅降低值显著偏大（t=2.26,2.45,2.83;P＜0.05）.结论 抑郁症患者的冲突信息加工功能受损,难治性抑郁患者受损程度大于一般性抑郁症患者.提示N270变化指标可能是难治性抑郁患者的潜在生物学标记.     

品行障碍青少年反馈相关负波特点的研究

目的:通过观察品行障碍(conduct disorder,CD)青少年反馈相关负波(Feedback-related negativity,FRN)波幅与潜伏期的变化,进一步探讨其反馈评价过程的特点。方法:对21名符合DSM-IV品行障碍诊断标准的13~17岁青少年和21名正常被试完成简单赌博任务时进行ERP检测。采用FRN的波幅和潜伏期作为指标,比较CD组与正常对照组青少年评价反馈结果过程的特点。结果:1CD组与对照组相比,FRN波幅差异具有统计学意义(P<0.05),CD组FRN波幅明显减小。2CD组与对照组相比,FRN潜伏期两组间比较差异无统计学意义(P>0.05)。结论:与正常组相比,品行障碍青少年的FRN存在异常,这可能在品行障碍的发病机制与症状表现中起着重要作用。FRN波幅可能是品行障碍的属性指标。     

音乐速度变化感知的失匹配负波

感知速度变化对音乐认知具有重要意义。本研究采用5个鼓点音构成标准等间距序列,再通过调整序列第3个刺激间隔(IOI)的长度引入局部速度扰动(IOI缩短:加速;IOI延长:减速)。从行为实验及被动听觉脑电实验入手,记录被试主动检测三种典型序列速度(快速:IOI=300 ms;中速:IOI=600 ms;慢速:IOI=900 ms)下的局部IOI扰动的行为响应,及自动感知中速序列(IOI=600 ms)局部IOI扰动的脑电响应。行为数据显示:中速的响应精度显著大于快速和慢速;加速与减速的辨别力指数在快速和慢速下均有显著差异,而在中速下无显著差异。脑电数据显示:在额中区电极Fz处,加速的失匹配负波(MMN)比减速的幅度更大、潜伏期更早。实验结果表明,中速序列的局部速度扰动对MMN的影响显著不同;即使在行为无偏差的中等序列速度下,大脑对局部速度扰动的感知加工还是有差异的。     

军人心理创伤后应激障碍患者与健康军人事件相关电位的对照研究

目的　探讨军人心理创伤后应激障碍 ( PTSD)患者 3种事件相关电位 ( ERP)的变异。方法　应用美国 Nicolet Bravo脑诱发电位仪 ,采用光和声成对刺激、反应时间以及听觉靶 -非靶刺激序列技术 ,检测 66例 PTSD和 3 6名正常人 ( NC)的关联性负变 ( CNV)、P30 0 、以及失配性负波 ( MMN)。结果　 1 CNV:M1 潜伏期 PTSD组 [( 5 0 3 .4± 1 3 9.2 ) ms]长于 NC组[( 4 2 0 .1± 1 2 3 .6) ms;P<0 .0 1 ],M2 波幅 PTSD组 [( 1 8.9± 7.9) μv]高于 NC组 [( 1 1 .7± 5 .8) μv;P<0 .0 1 ],指令信号后负变化 ( PINV)的出现率 PTSD组 ( 3 9% )高于 NC组 ( 3 % ;P<0 .0 1 )。 2 P30 0 :在靶刺激中 ,Cz脑区的 P3潜伏期 PTSD组[( 3 1 5 .4± 1 7.8) ms]短于 NC组 [( 3 3 6.7± 1 5 .5 ) ms;P<0 .0 1 ],Pz脑区的 N2 潜伏期 PTSD组 [( 2 78.5± 2 1 .8) ms]长于 NC组 [( 2 63 .4± 1 4.2 ) ms;P<0 .0 1 ],Pz脑区的 P3波幅 PTSD组 [( 3 .4± 1 .8) μv]低于 NC组 [( 5 .9± 2 .4) μv;P<0 .0 1 ]。在非靶刺激中 ,Cz脑区的 P2 波幅 PTSD组 [( 2 .5± 1 .4) μv]低于 NC组 [( 3 .4± 0 .1 ) μv;P<0 .0 1 ]。 3 MMN:潜伏期 PTSD组[( 2 1 4.2± 2 5 .7) ms]长于 NC组 [( 1 93 .7± 2 2 .6) ms;P<0 .0 1 ],波幅 PTSD组 [( 8.5     

精神分裂症患者失匹性负波(MMN)研究

目的:了解首发精神分裂症患者失匹性负波(MMN)的特征以及治疗缓解后MMN的变化。方法:应用美国Bravo脑电生理仪,记录45例首发精神分裂症患者和40名健康人的MMN,同时记录P300电位比较,并用阳性和阴性症状量表(PANSS)评定患者精神症状。患者组于治疗5周和12周时进行MMN随访。结果:(1)与正常组比较,首发精神分裂症组的MMN潜伏期延迟和波幅降低(正常组199·7±29·9ms和7·8±3·8μV,患者组221·4±32·6ms,4·5±3·3μV,P均<0·01),患者组P300中靶潜伏期P3同时延迟(P<0·01)。(2)MMN潜伏期延长和波幅低,与PANSS阳性症状和思维障碍分呈负相关(P<0·05~0·01)。(3)患者组经治疗12周后,MMN波幅呈增大改变和潜伏期缩短(P<0·01),反映患者的认知功能改善。结论:MMN技术可反映首发精神分裂症患者诱发脑电的自动加工过程。MMN可作为精神分裂症患者的临床应用检测指标。     

反馈相关负波与心理病理之间关系研究的进展

反馈相关负波(feedback-related negativity,FRN)是由外部反馈诱发的一种脑电波成分,最大峰值在负性反馈之后的250-300ms左右,研究发现偶极子源多定位于前扣带回(anterior cingulate cortex,ACC)附近.目前对于FRN的功能意义的解释主要有强化学习理论和情绪动机假说.多项研究表明FRN与多种心理疾病改变和相关人格特质之间存在相关.     

老年抑郁症的非匹配负波对照研究

目的了解老年抑郁症患者非匹配负波(MMN)Pz脑区的特点。方法应用Nicolet Bravo脑诱发电位仪,对38例老年抑郁症患者、34例抑郁症对照组和39名健康成人进行了MMNPz脑区检测。结果与健康对照组相比,老年抑郁症组、抑郁症对照组患者MMN潜伏期延迟(t=7.169,P0.01),同时波幅降低(t=6.891,P0.01)。结论 MMN新技术适于精神科临床应用。     

The Effects of Channel-Selective Attention on the Mismatch Negativity Wave Elicited by Deviant Tones

The mismatch negativity (MMN) is an event-related brain potential elicited by infrequent, physically deviant sounds in a sequence of repetitive auditory stimuli. Two dichotic listening experiments that were designed to optimize the selective focusing of attention provided a strong test of Näätänen's proposal that the MMN is unaffected by attention and reflects the operation of a strongly automatic mismatch detection system. In Experiment 1, tones were presented at intervals of 120-320 ms, and the deviant tones (intensity decrements) in both the attended and unattended ears elicited negative waves consistent in waveshape, latency, and distribution with previously described MMNs. In contrast to previous reports, however, the MMN elicited by the unattended-channel deviant was markedly reduced (peak amplitude of less than 1 μV) relative to the corresponding negative wave elicited by the attended-channel deviants (3–4 μV), as well as relative to previously reported MMNs (3–6 μV) elicited by comparable deviations in stimulus intensity. In Experiment 2, which employed interstimulus intervals of 65–205 ms, the unattended-channel MMN elicited by the deviant fainter tones was barely discernible, whereas the corresponding attended-channel negativity was again about 3-4 μV.
These findings call into question the assertion that the auditory mismatch detection process and the associated MMN wave are wholly independent of attentional influence. Rather, these data provide evidence that the processing of stimuli in unattended channels can be attenuated or gated at an early sensory level under conditions of highly focused auditory selective attention.     

Mismatch Negativity Outside Strong Attentional Focus: A Commentary on Woldorff et al. (1991)

Several previous papers have suggested that the mismatch negativity (MMN), an event-related potential (ERP) component specific to stimulus change after repetition, is fully automatic, that is, not affected by attention. Woldorff, Hackley, and Hillyard (1991), however, report that the MMN elicited by an intensity decrement of a repeating stimulus is considerably attenuated when attention is strongly focused on other stimuli. The present commentary attributes most of this effect to attention effects on ERP components other than the MMN but also admits that some attentional reduction of the MMN component indeed occurred. This attenuation was interpreted by Woldorff et al. as indicating suppression of early sensory processing in unattended channels, but this is contraindicated by some very recent data from the present author's laboratory and elsewhere showing that the MMN to frequency change is not attenuated outside a strong attentional focus. Consequently, an alternative explanation is proposed for Woldorff et al.'s important finding.     

Short-Term Habituation and Dishabituation of the Mismatch Negativity of the ERP

Standard tones of 1000 Hz and deviant tones of 1250 Hz were presented in random order, 1 stimulus/second. The probabilities of the standards and deviants were 90% and 10%, respectively. In one condition the subject counted the deviant stimuli and in the other condition he/she read a comic book. ERPs were separately averaged to 1) the standard preceding the deviant, 2) the “first deviant” preceded by at least 4 standards, 3) the “second deviant” (an occasional deviant immediately following the “first deviant”), 4) the first and 5) the second standard following the “first deviant,” 6) the first and 7) the second standard following the “second deviant.” It was found that the mismatch negativity evoked in both conditions by the first deviant was considerably larger than to the second deviant. Also the first standard following the first deviant evoked the mismatch negativity. The results are discussed in terms of parallel neuronal models of the stimuli as reflected by the mismatch negativity.     

Mismatch negativity (MMN), the deviance-elicited auditory deflection, explained

The current review constitutes the first comprehensive look at the possibility that the mismatch negativity (MMN, the deflection of the auditory ERP/ERF elicited by stimulus change) might be generated by so-called fresh-afferent neuronal activity. This possibility has been repeatedly ruled out for the past 30 years, with the prevailing theoretical accounts relying on a memory-based explanation instead. We propose that the MMN is, in essence, a latency- and amplitude-modulated expression of the auditory N1 response, generated by fresh-afferent activity of cortical neurons that are under nonuniform levels of adaptation.     

Mismatch negativity reflects numbers of tones of specific frequencies in humans

The human brain can automatically quantify objects and events. The mismatch negativity (MMN) of the event-related potential (ERP) was recently found to reflect one such ability in the auditory modality. The present study aimed to further validate the finding. ERPs were recorded in adult humans who passively listened to a series of 300-ms sequences of tones. The sequences occurred at 300-ms silent intervals. They comprised a total of six tones that each was either 440 or 660 Hz in frequency. MMN was found for a rare 4:2 ratio interspersed with a frequent 3:3 ratio between the tones of the different frequencies in a sequence, suggesting the ability of the human brain to preattentively discriminate numbers of sounds of specific frequencies at least at a 3:2 ratio.     

Mismatch negativity to auditory stimulus change recorded directly from the human temporal cortex

Mismatch negativity (MMN) is an event-related potential (ERP) component elicited by any discernible change in a repetitive sound even in the absence of attention. Previous studies have established that MMN is generated by change detection in a process comparing the deviant sensory input with the neural memory trace encoding the physical features of the repetitive sound. In the present study, we recorded MMNs to tonal frequency changes directly from the human temporal cortex of patients with electrodes implanted in the brain for diagnosis and therapy. The intracranially recorded MMN was found to be attention independent and modality specific. It was confined to a rather small area in temporal cortex, which was different from the structures where attention-dependent N2 and P3 responses to the frequency change could be recorded.