MEDICAL ENGINEERING COOPERATIVE STUDY OF EVENT-RELATED BRAIN POTENTIAL N400 IN PATIENTS WITH BIPOLAR DEPRESSION

Objective:To explore the difference and its clinical significance of event-related potential N400 in patients with bipolar depression,unipolar depression and schizophrenia Methods:It was N400 detection for 24 cases of bipolar depression,25 cases of unipolar depression,26 cases of schizophrenia and 28 healthy adults.All were tested with China Runjie WJ-1 ERP Instrument,congruent ending words of Chinese idioms(matching)and incongruent ending words of Chinese idioms(mismatching)mode.Results:(1)Compared with healthy adults in the control group,N400 latencies were prolonged in Cz brain regions and amplitudes were decreased period of three groups of patients before taking the medicine.(2)The delay in latencies and the decrease in amplitude of schizophrenia N400 were negatively correlated with the PANSS total score of the neuropsychological scale.(3)The abnormal degree of N400 in bipolar depression group was between unipolar depression group and schizophrenia group.Conclusions:We initially believe that(1)the bipolar depression group may be an intermediate state between unipolar depression and schizophrenia.(2)Bipolar depression with psychotic symptoms may have specific language barriers and N400 abnormalities.(3)After the next ERP follow-up,N400 can be used as a laboratory aid for identifying unipolar depression,bipolar depression and schizophrenia.

Effect of variable number of tandem repeats polymorphism in the human dopamine transporter gene on conflict information processing according to event-related potential

The dopamine transporter （DAT） is responsible for dopamine reuptake from the synaptic cleft. A variable number of tandem repeats polymorphism in the DAT gene is related to DAT availability and has been associated with cognition. With the advantage of high-time resolution, event-related potential is an important method to study the time course of human information processing. Previous results have suggested that dopamine exhibits a close relationship with conflicting information processing. Therefore, the present study assumed that conflicting information processing could be influenced by DAT variable number of tandem repeats polymorphism. To confirm this, the present study analyzed the influence of DAT genotypes on N270, which is presumed to reflect neural activity of conflict information processing in young healthy adults. A S1-S2 matching task was performed in healthy adults with 10/10 genotype （n = 14） and 10/9 genotypes （n = 14）, respectively, when event-related potentials were recorded. Results demonstrated that subjects with the 10/10 genotype exhibited shorter N270 latency and quicker reaction times compared with subjects with the 10/9 genotype. There were no differences in N270 amplitude between the two genotypes. These results suggested that 10/10 genotype subjects more efficiently processed conflict information.

Behavioral inhibition in female college students with schizotypal traits: An event-related potential study

This study investigated behavioral inhibition in female college students with psychometrically defined schizotypal traits using a Go/NoGo task and event-related potentials (ERPs). The schizotypal-trait (n = 15) and normal control (n = 15) groups were selected based on scores of the Schizotypal Personality Questionnaire (SPQ). The Go/NoGo task consisted of Go (requires response) and NoGo (requires no response) conditions. In terms of response time and accuracy rate for the Go/NoGo task, the two groups did not differ significantly. In terms of ERPs, the control group showed greater N2 amplitudes in response to NoGo (NoGo-N2) than to Go stimuli (Go-N2), whereas the schizotypal-trait group showed no significant difference in NoGo-N2 and Go-N2 amplitudes. In addition, the schizotypal-trait group showed reduced NoGo-N2 amplitudes at the frontal site compared to controls, and an association between SPQ scores and NoGo-N2 amplitudes measured at the frontal site. The two groups did not differ in P3 amplitudes. Since the N2 reflects the detection of response conflict and behavioral inhibition, the present results indicate that nonclinical individuals with schizotypal traits have difficulties in detecting response conflict and behavioral inhibition.

汉语成语结尾字事件相关电位N_(400)的研究

目的 通过记录汉语成语结尾字匹配与不匹配事件相关电位N40 0 的变化 ,探讨视觉词语认知模式及汉字认知加工特征。方法 采用南方医院研制的事件相关电位仪 ,对 15例 2 1～ 3 6岁健康人右利手受试者中 ,进行汉语成语正常结尾字 (匹配字 )与歧义字 (不匹配字 )N40 0 的研究。结果 受试者对结尾词匹配与不匹配组的N40 0 成分在潜伏期及波幅差异有显著性 (P≤ 0 .0 1) ,不匹配组的N40 0 波幅高 ,潜伏期长。N40 0 广泛分布于各区 ,左侧比右侧波幅偏高。结论 汉语成语结尾字匹配与不匹配的N40 0 与字词认知中的语义密切相关 ,有一定的临床价值 ,可用于临床多种伴有语言障碍疾病的评估。

正常人汉语句子事件相关电位N_(400)的研究

目的研究汉语句子结尾词匹配与不匹配事件相关电位N400的变化,探讨正常人汉语句子N400的特征.方法对15名21～36岁右利手健康受试者,进行汉语正常句子结尾匹配词(匹配)与句子结尾歧义词(不匹配)N400的研究.结果受试者对句子结尾词匹配与不匹配的N400成分在潜伏期及波幅有显著性差异(P<0.05),句子不匹配结尾词的N400潜伏期较长,N400波幅高.N400广泛分布于脑部各区,左侧波幅偏高.结论汉语句子结尾字匹配与不匹配的N400与字词认知中的语义密切相关,可作为一个有临床价值的认知电位而用于临床多种伴有语言障碍疾病的评估.

The Electrophysiology of Semantic Processing in Individuals with Autism Spectrum Disorder:A Meta-Analysis

Language difficulties vary widely among people with autism spectrum disorder(ASD).However,the semantic processing of autistic person and its underlying electrophysiological mechanism are still unclear.This meta-analysis aimed to explore the disturbance of semantic processing in patients with ASD.PubMed,Web of Science,and Embase were searched for eventrelated potential(ERP)studies on semantic processing in autistic people published in English before September 01,2022.Pooled estimates were calculated by fixed-effects or random-effects models according to the heterogeneity using Comprehensive Meta-Analysis 2.0.The potential moderators were explored by meta-regression and subgroup analysis.This meta-analysis has been registered at the Prospero International Prospective Register of Systematic Reviews(no.CRD 42021265852).A total of 14 articles and 18 studies,including 254 autistic people and 262 neurodevelopmental people were included in this meta-analysis.Compared to the comparison group,autistic people showed an overall reduced N400 amplitude(Hedges’g=0.350,p<0.001)in response to linguistic stimuli instead of non-linguistic stimuli.The N400 amplitude was affected by verbal intelligence and gender.The reduced overall N400 amplitude in autistic people under linguistic stimuli suggests a linguistic-specific deficit in semantic processing in individuals of autism.The decrease of N400 amplitude might be a promising indication of the pool language capacity of autism.

Auditory ERP Differences in the Perception of Anticipated Speech Sequences in 5 - 6 Years Old Children and Adults

The perception of complex auditory information such as complete speech sequences develops during human ontogeny. In order to explore age differences in the auditory perception of predictable speech sequences we compared event-related potentials (ERPs) recorded in 5- to 6-year-old children (N = 15) and adults (N = 15) in response to anticipated speech sequences as successive and reverse digital series with randomly omitted digits. The ERPs obtained from the omitted digits significantly differed in the amplitude and latency of the N200 and P300 components between adults and children, the N400 and LPC components were more pronounced in children in the right frontal area for the digits presentation. These findings indicate that the perception of a successive speech structure is less automated in children and requires a detailed analysis of the successive structure and error detection. These differences in auditory ERPs reflect developmental changes in the auditory perception of speech sequences and can serve as indicators of the maturity of cognitive functions in children.

Effects of Risperidone and Paliperidone on Brain-Derived Neurotrophic Factor and N400 in First-Episode Schizophrenia

Background：Risperidone and paliperidone have been the mainstay treatment for schizophrenia and their potential role in neuroprotection could be associated with brain-derived neurotrophic factor （BDNF） and N400 （an event-related brain potential component）.So far,different effects on both BDNF and N400 were reported in relation to various antipsychotic treatments.However,few studies have been conducted on the mechanism ofrisperidone and paliperidone on BDNF and N400.This study aimed to compare the effects ofrisperidone and paliperidone on BDNF and the N400 component of the event-related brain potential in patients with first-episode schizophrenia.Methods：Ninety-eight patients with first-episode schizophrenia were randomly divided into the risperidone and paliperidone groups and treated with risperidone and paliperidone,respectively,for 12 weeks.Serum BDNF level,the latency,and amplitude of the N400 event-related potential before and after the treatment and Positive and Negative Syndrome Scale （PANSS） scores were compared between the two groups.Results：A total of 94 patients were included in the final analysis （47 patients in each group）.After the treatment,the serum BDNF levels in both groups increased （all P 〈 0.01）,while no significant difference in serum BDNF level was found between the groups before and after the treatment （all P 〉 0.05）.After the treatment,N400 amplitudes were increased （from 4.73 ± 2.86 μv and 4.51 ± 4.63 μv to 5.35 ± 4.18 μv and 5.52 ± 3.08 μv,respectively） under congruent condition in both risperidone and paliperidone groups （all P 〈 0.01）.Under incongruent conditions,the N400 latencies were shortened in the paliperidone group （from 424.13 ± 110.42 ms to 4.7.41 ± 154.59 ms,P 〈 0.05）,and the N400 amplitudes were increased in the risperidone group （from 5.80 ± 3.50 μv to 7.17 ± 5.51 μv,P 〈 0.01）.After treatment,the total PANSS score in both groups decreased significantly （all P 〈 0.01）,but the difference between the groups was not significant （P 〉 0.05）.A negative correlation between the reduction rate of the PANSS score and the increase in serum BDNF level after the treatment was found in the paliperidone group but not in the risperidone group.Conclusions：Both risperidone and paliperidone could increase the serum BDNF levels in patients with first-episode schizophrenia and improve their cognitive function （N400 latency and amplitude）,but their antipsychotic mechanisms might differ.

Follow-up of N400 in the Rehabilitation of First-episode Schizophrenia

Background：The N400 component of event-related potentials （ERP） has recently drawn widespread attention at home and abroad.This study was to explore the relationship between N400 changes and risperidone treatment and rehabilitation in first-episode schizophrenia （FES）.Methods：ERP component N400 was recorded by Guangzhou Runjie W J-l ERP instruments,in 58 FES before and 6 months,15 months after risperidone treatment,and in 62 normal controls.The patients＇ syndromes were assessed by Positive and Negative Syndrome Scale （PANSS）.And the stimuli are Chinese sentences with matching （congruent） or mismatching （incongruent） ending words.Results：N400 latencies were prolonged,and amplitudes were decreased in Cz,Pz,Fz,C3,C4,in FES compared with in NC,before treatment.The prolonged N400 latencies and decreased amplitudes were negatively correlated with the patients＇ positive scale and total scale of PANSS.There are significant differences of N400 amplitudes and latencies in 6 months and 15 months follow-up after treatment.Before treatment,6 months and 15 months after treatment,N400 latencies are 446 ± 35 ms,440 ± 37 ms,414 ± 31 ms （F =9.72,P 〈 0.01） in incongruent situation;N400 amplitudes are 5.2 ± 4.6 μtⅤ,5.7 ± 4.8 μⅤ,7.3 ± 5.0 μⅤ （F =2.06,P 〉 0.05） in congruent situation,and 8.5 ± 5.9 μⅤ,10.1 ± 5.0 μⅤ,11.9 ± 7.0 μⅤ （F =3.697,P 〈 0.05） in incongruent situation.Conclusions：N400 could be used to predict the effects of treatment of schizophrenia to some degree.The linguistic and cognitive impairment in schizophrenia can be improved by antipsychotic drugs.

Time-course of perceptual processing of “hole” and “no-hole”figures: An ERP study

Closure or the presence of a ＂hole＂ is an emergent perceptual feature that can be extracted by the visual system early on. This feature has been shown to have perceptual advantages over openness or ＂no-hole＂. in this study, we investigated when and how the human brain differentiates between ＂hole＂ and ＂no-hole＂ figures. Event-related potentials （ERPs） were recorded during a passive observation paradigm. Two pairs of simple figures （Experiment 1） and two sets of Greek letters （Experiment 2） were used as stimuli. The ERPs of ＂hole＂ and ＂no-hole＂ figures differed ~90 ms after stimulus onset： ＂hole＂ figures elicited smaller P1 and N1 amplitudes than ＂no-hole＂ figures. These suggest that both P1 and N1 components are sensitive to the difference between ＂hole＂ and ＂no-hole＂ figures; perception of ＂hole＂ and ＂no-hole＂ figures might be differentiated early during visual processing.

长期海洛因戒断者的冲突适应能力——来自ERPs的证据

目的:海洛因滥用导致海洛因依赖者认知控制功能损伤,本研究通过使用ERP技术来探究这种损伤在长期物质戒断后的恢复水平。方法:本研究对比参与字母Flanker任务的长期海洛因戒断组和正常组冲突适应能力的时程动态过程。结果:(1)两组被试在冲突试次上的反应时(RT_(I))均显著长于一致试次(RT_(C)),Flanker冲突效应(RT_(I-C))没有组间差异;进一步检验发现,两组被试的试次间调节的反应时之差(RT_(cI-iI))差异不显著。(2)对照组在一致-冲突试次(cI)条件下引发的N2平均振幅显著大于冲突-冲突试次条件(iI),而长期海洛因戒断组N2效应消失。(3)长期海洛因戒断组在冲动性量表上的得分显著高于对照组。结论:行为和电生理指标出现分离性的结果,即长期海洛因戒断组在反应时上能够较好的解决冲突,但是长期吸食海洛因导致其认知控制功能损伤。