Correlation of cognitive function with acetylcholinesterase activity and P300 event-related potential of patients with type 2 diabetes mellitus

BACKGROUND： At present, central cholinergic neuron system is regarded the most major structural basis of cognitive function. Changes in structure of cholinergic neuron system of brain and receptor expression after brain injury can cause cognitive impairment. OBJECTIVE＂ To comparatively observe the intelligence quotient （IQ）, latent period and wave amplitude of P300 event-related potential and the difference of activity of acetylcholinesterase （ACHE） in blood and cerebrospinal fluid between patients with type 2 diabetes mellitus and with non-diabetes mellitus, and analyze the correlation of IQ of cognitive impairment patients with diabetes mellitus with AChE activity, latent period and wave amplitude of P300 event-related potential in cerebrospinal fluid. DESIGN： Correlation analysis of contrast observation SETTING： Department of Endocrinology, Affiliated Hospital of Binzhou Medical College PARTICIPANTS： Totally 32 patients with type 2 diabetes mellitus who received the treatment in the Department of Endocrinology, Affiliated Hospital of Binzhou Medical College between April 2004 and April 2005 were recruited, serving as diabetes mellitus group. They, including 19 male and 13 female, aged 49 to 73 years, with disease course of 4 to 11 years, all met the diagnostic criteria of diabetes mellitus revised by World Health Organization in 1999. Another 30 patients with non-diabetes mellitus who homeochronously underwent lumbar anesthesia in the Department of Surgery and Department of Gynecology were recruited, serving as non-diabetes mellitus group. The 30 patients included 18 male and 12 female, and their age ranged from 46 to 71 years. Informed consents of detected items were obtained from the involved patients. METHODS： ① Evaluation,on IQ： The IQ of involved subjects was evaluated with Chinese Version of the Wechsler Adult Intelligence Scale revised by Gong Yao-xian （WAIS-RC）. WAIS-RC included 6 verbal subscales and 5 performance subscales. The test scores of the 11 subscales integrated into the scores of the whole scale, and the scores on the WAIS-RC included verbal IQ （VlQ）, performance IQ （PIQ） and full scale IQ （FIQ）. FIQ ≤79 scores indicated low IQ and FIQ≤69 indicated intelligence impairment. ② Detection of P300 wave： P300 wave was detected with evoked potential instrument （MYTOPRO, Italian）, and data of latent period and amplitude of P300 event-related potential were automatically shown by computer. ③ Detection of AChE activity in blood and cerebrospinal fluid： Activity of AChE of blood and cerebrospinal fluid was measured with biochemical methods by using CORNING-560 autoanalyzer.④Correlation analysis： Correlation of FIQ with AChE of cerebrospinal fluid and P300 wave of patients with type 2 diabetes mellitus was analyzed, t test was used in intergroup comparison and linear correlation analysis for relevant treatment. MAIN OUTCOME MEASURES： ① Comparison of IQ, latent period and wave amplitude of P300 wave as well as the activity of AChE between two groups. ② Analysis on the correlation of FIQ of patients with type 2 diabetes mellitus with AChE of cerebrospinal fluid and P300 wave. RESULTS： Thirty-two patients with diabetes mellitus and 30 non-diabetes mellitus participated in the result analysis. ①Comparison of IQ, latent period and wave amplitude of P300 wave as well as the activity of AChE between two groups： The scores of VIP, PIQ and FIQ of patients with type 2 diabetes mellitus were （97.4±10.4）. （92.6±8.4） and （95.2±9.7） scores, respectively; and those of patients with non-diabetes mellitus were （104.7±9.6）, （102.5±8.5）and（102.7±8.9） scores, respectively, and P 〈 0.05-0.01 was set in intergroup comparison. The latent period of P300 wave at points Fz , Cz and Pz of patients with type 2 diabetes mellitus was （370.8±41.8）.（371.5±39.1）and （375.1±43.1） ms, respectively, and that of patients with non-diabetes mellitus was （ 332.1 ±28.3 ）, （335.7 ±29.4）and （339.7 ±27.3） ms, respectively, and P 〈 0.01 was set in intergroup comparison; Wave amplitude of P300 of patients with type 2 diabetes mellitus was （8.6±4.1）,（8.6±4.0） and （7.7±4.0） μV, respectively and that of patients with non-diabetes mellitus was （11.9±4.1）,（11.5±4.4） and （10.9±5.0） μV, respectively , and P 〈 0.05-0.01 was set in intergroup comparison; The level of AChE in blood and cerebrospinal fluid of patients with type 2 diabetes mellitus was （235.61 ±50.34）and （17.89±4.46） μkat/L, respectively, which was significantly higher than that of patients with non-diabetes mellitus [（205.03±44.15）and （14.63±0.48） μkat /L, respectively], and P 〈 0.05-0.01 was set in the intergroup comparison. ② Correlation of FIQ value of patients with type 2 diabetes mellitus with AChE of cerebrospinal fluid and P300 wave： The value of FIQ was significantly negatively correlated with the AChE activity of cerebrospinal fluid （r=-0.588 1, P 〈 0.01 ）, significantly negatively correlated with the latent period at points Fz. C and Pz of P300 wave （r= -0.700 5, -0.689 4, -0.688 5, P 〈 0.01 ）, and significantly positively correlated with the amplitude at points Fz . Cz and Pz of P300 wave（r= 0.607 4,0.616 1,0.592 0,P 〈 0.01 ）. CONCLUSION： ① Cognitive impairment of patients with type 2 diabetes mellitus might be related to the increase of activity of AChE in cerebrospinal fluid. ②Combined application of examination of P300 wave and evaluation of IQ is more useful in deciding the state of cognitive function of patients with type 2 diabetes mellitus.

Relationships among Event-Related Potentials, Memory, and Schizophrenic Symptoms in College Students with Schizotypal-Traits

The present study investigated the relationships among event-related potentials (ERPs), memory, and schizophrenic symptoms in college students with schizotypal-traits. Scores on the Schizotypal Personality Questionnaire (SPQ) were used to categorize the participants into schizotypal-trait (n = 30) and normal control (n = 37) groups. ERPs were assessed using an auditory oddball paradigm, in which a series of standard tones (1000 Hz) and target tones (1500 Hz) were presented;participants were asked to count the number of presented target tones. The verbal memory and visual memory of the participants were evaluated using the Korean version of the California Verbal Learning Test (K-CVLT) and the Rey-Osterrieth Complex Figure Test (RCFT), respectively. The schizotypal-trait and control groups did not differ in terms of age, educational level, IQ score, accuracy on the auditory oddball task, or performance on the K-CVLT and RCFT measures. However, the schizotypal-trait group exhibited significantly smaller P300 amplitudes than the control group. Additionally, the P300 amplitudes measured at Cz and Pz were negatively correlated with the cognitive-perceptual factor scores on the SPQ. Thus, the present results indicate that reduced P300 amplitudes may represent a biological marker of schizophrenia.

Differential cognitive responses to guqin music and piano music in Chinese subjects： an event-related potential study

Objective To compare the cognitive effects of guqin （the oldest Chinese instrument） music and piano music. Methods Behavioral and event-related potential （ERP） data in a standard two-stimulus auditory oddball task were recorded and analyzed. Results This study replicated the previous results of culture-familiar music effect on Chinese subjects： the greater P300 amplitude in frontal areas in a culture-familiar music environment. At the same time, the difference between guqin music and piano music was observed in NI and later positive complex （LPC： including P300 and P500）： a relatively higher participation of right anterior-temporal areas in Chinese subjects. Conclusion The results suggest that the special features of ERP responses to guqin music are the outcome of Chinese tonal language environments given the similarity between Guqin＇s tones and Mandarin lexical tones.

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.

THE EFFECT OF ELECTROACUPUNCTURE ON AUDITORY P300 POTENTIAL IN MONGOLISM CASES

In treating children with mongolism(Down’s syndrome)with electroacupuncture,thelatent period of P3 is shortened,which shows that the cerebral reaction to externalstimulus in classification,encoding and recognition is accelerated.Along with the elevatedP3 amplitude,the cerebrum is more capable of processing the external information,showing improvement of the mental state.

精神分裂症患者事件相关电位P300及其与发病次数的关系

目的探讨首发与复发精神分裂症患者的电生理机制差异。方法对28例精神分裂症首次发作患者(首发组)、32例复发精神分裂症患者(复发组)进行事件相关电位P300的测定,测量其错误数和反应时,潜伏期和波幅,并与30名健康志愿者的结果进行比较。结果①患者组的反应时显著长于对照组(t=8.25,P<0.05);正确率差异无统计学意义;②与对照组相比,患者组在C3、C4电极处,潜伏期均显著延迟(t=2.47,2.56;P<0.05);Fz、Cz、C3、C4点波幅均显著降低(t=3.12,4.14,4.27,3.08;P<0.05);③与首发组相比,复发组在C3、C4、Fz点的潜伏期显著延迟(t=2.58,3.07,6.78;P<0.05);C3、C4、Fz、Cz点波幅均显著降低(t=5.13,4.55,8.35,4.70;P<0.05)。结论首发、复发精神分裂症患者认知功能均受损,且复发患者受损程度大于首发患者。提示患者认知功能受损是一个累积下降的过程。

精神分裂症患者血清同型半胱氨酸水平与P300的相关

目的探讨精神分裂症患者血清同型半胱氨酸水平(Hcy)与事件相关电位P300的关系。方法随机将年龄在18~65岁之间符合CCMD-3精神分裂症诊断标准患者45例作为试验组,选择45例健康者作为对照组。同时采用酶联免疫法检测血清Hcy水平及以P300评定认知功能,并将结果加以分析、比较。结果与对照组相比,研究组CZ、PZ点N1、P2、N2、P3潜伏期均明显延长(t=2.36~3.86,P<0.05或0.01),研究组CZ、PZ点N2、P3波幅明显降低(t=3.06~5.27,P<0.01);研究组血清Hcy水平高于对照组(t=2.76,P<0.01);CZ、PZ点P300潜伏期与血清Hcy水平呈正相关(r=0.36~0.49,P<0.05或0.01),CZ、PZ点P300波幅与血清Hcy水平则呈负相关(r=-0.47^-0.51,P<0.01)。结论精神分裂症患者血清Hcy水平升高,其认知功能损害可能与血清Hcy代谢异常有关。

毒品成瘾的ERP研究进展

把ERP研究技术应用于毒品成瘾研究将有利于对成瘾问题的脑机制进行更深入的探讨,为有效诊断和戒除毒品成瘾提供更直接的生理指标。目前的研究主要集中在鉴别和诊断毒品成瘾的ERP成分、毒品成瘾导致认知障碍或缺失的脑机制以及毒品成瘾的生理心理机制等三个方面。通过对毒品成瘾ERP研究现状的介绍,可以推测今后的研究将着重于加强对毒品成瘾心理机制、毒品成瘾导致的认知功能障碍和情感障碍研究范式的拓展以及将多种ERP成分与毒品成瘾研究更有效地结合起来。

P300评估抑郁症的病程与认知功能障碍的相关性

目的 采用事件相关电位P300的改变来研究抑郁症患者的病程与认知功能障碍的相关性.方法 对40～ 50岁年龄段的115例抑郁症患者,以病程＞2年为标准分为两组进行事件相关电位研究.结果 ＞2年抑郁症患者组P300潜伏期较＜2年组延长（U=3.15,P＜0.05）,P300波幅较＜2年组降低（U=4.79,P＜0.001）.结论 抑郁症患者的病程越长、认知功能损害程度越严重.

Connecting the P300 to the diagnosis and prognosis of unconscious patients

The residual consciousness of unconscious patients can be detected by studying the P300, a wave among event-related potentials. Previous studies have applied tones, the subject＇s name and other names as stimuli. However, the results were not satisfactory. In this study, we changed the constituent order of subjects＇ two-character names to create derived names. The subject＇s derived names, together with tones and their own names, were used as auditory stimuli in event-related potential experiments. Healthy controls and unconscious patients were included in this study and made to listen to these auditory stimuli. In the two paradigms, a sine tone followed by the subject＇s own name and the subject＇s derived name followed by the subject＇s own name were used as standard and deviant stimuli, respectively. The results showed that all healthy controls had the P300 using both paradigms, and that the P300 in the second paradigm had a longer latency and two peaks. All minimally conscious state patients had the P300 in the first paradigm and the majority of them had the P300 in the second paradigm. Most vegetative state patients had no P300. Patients who showed the P300 in the two paradigms had more residual consciousness, and patients with the two-peak P300 had a higher probability of awakening within a short time. Our experimental findings suggest that the P300 event-related potential could reflect the conscious state of unconscious patients.

P300 change and cognitive behavioral therapy in subjects with Internet addiction disorder A 3-month follow-up study

Event-related potential studies of cognitive function in addiction behaviors have focused on the P300 event-related potential component. The current study investigated the association between P300 component and Internet addiction disorder. We found that individuals with Internet addiction disorder exhibited significantly longer P300 latencies than controls （N2： P = 0.035; P3a： P = 0.031 P3b： P = 0.043） and similar P300 amplitudes compared to control participants. After 3 months of cognitive behavioral therapy, P300 latencies decreased significantly in the P3a and P3b （P3a： P = 0.045; P3b： P = 0.062）. These results suggest that deficits in cognitive function may be involved in Internet addiction disorder, and that clinical psychological treatment may be effective.

Automatically detecting auditory P300 in several trials

A method was demonstrated based on Infomax independent component analysis(Infomax ICA) for automatically extracting auditory P300 signals within several trials. A signaling equilibrium algorithm was proposed to enhance the effectiveness of the Infomax ICA decomposition. After the mixed signal was decomposed by Infomax ICA, the independent component(IC) used in auditory P300 reconstruction was automatically chosen by using the standard deviation of the fixed temporal pattern. And the result of auditory P300 was reconstructed using the selected ICs. The experimental results show that the auditory P300 can be detected automatically within five trials. The Pearson correlation coefficient between the standard signal and the signal detected using the proposed method is significantly greater than that between the standard signal and the signal detected using the average method within five trials. The wave pattern result obtained using the proposed algorithm is better and more similar to the standard signal than that obtained by the average method for the same number of trials. Therefore, the proposed method can automatically detect the effective auditory P300 within several trials.

P300 EEG Recognition Based on SVM Approach

In this paper, we used SVM method to detect P300 signal. Before training a classification parameter for the SVM, several preprocessing operations were applied to the data including filtering, downsampling, single trial extraction, windsorizing, electrode selection et al. With the SVM algorithm, the classification accuracy could be up to above 80%. In some cases, the accuracy could reach 100%. It is suitable to use SVM for P300 EEG recognition in the P300-based brain-computer interface (BCI) system. Our further work will include the improvement to yield higher classification accuracy using fewer trials.

Dissociated neural potential for processing strategies between decimals and fractions

The entity and symbolic fraction comparison tasks separating identification and semantic access stages based on event-related potential technology were used to investigate neural differences between fraction and decimal strategies in magnitude processing of nonsymbolic entities and symbolic numbers.The experimental results show that continuous entities elicit stronger left-lateralized anterior N2 in decimals,while discretized ones elicit more significant right-lateralized posterior N2 in fractions during the identification stage.On the other hand,decimals elicit stronger N2 over the left-lateralized fronto-central sites while fractions elicit the more profound P2 over the right-lateralized fronto-central sites and N2 at biparietal regions during the semantic access stage.Hence,for nonsymbolic entity processing,alignments of decimals and continuous entities activate the phonological network,while alignments of fractions and discretized entities trigger the visuospatial regions.For symbolic numbers processing,exact strategies with rote arithmetic retrieval in verbal format are used in decimal processing,while approximate strategies with complex magnitude processing in a visuospatial format are used in fraction processing.

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.

Progress in the application of P300 in depression

Depression is a common mental disor-der with low mood,loss of interest and pleasure as main symptoms.Because of depending on the subjective diag-nosis of psychiatrists,its diagnosis is no reliable objective basis.P300 research findings can be used as an objective diagnostic indicator for patients.This paper mainly intro-duces the current research status of event-related poten-tials for depression and introduces the scientific research and clinical significance of P300 for depression.

The Impact of Age and Duration of Cochlear Implant in a Congenital Deaf Population: An ERP Study

Objective: It is well known that patients with Cochlear Implant (CI) have a large inter-individual variability in linguistic and auditory performances. This can be related to individual auditory processing abilities and integrity of auditory system from auditory nerve to cerebral cortex. P300 can be used for the evaluation of central auditory functions in people with hearing loss and CI. No studies considered the P300 in the population of prelingually deafened adults that underwent CI in old age. The aim of this study is to assess Event Related Potential (ERP) in patients with congenital profound hearing loss with early or late implantation and evaluate these results respect to an age-matched normal hearing group. Methods: ERPs (N100, N200 and P300) and auditory benefit testing (pure tone average and speech audiometric test) and auditory perception testing (Categories of Auditory Performance—CAP) were evaluated in all subjects with their device. Results: All mean latencies (N100, N200 and P300) were found greater in patients group compared to control group. When analyzing all measures in patient group, we did not find any significant differences according to age of implant while significant difference (p > 0.05) in N100 amplitude (p = 0.045) and P300 latency (p = 0.035) were found according to time of CI use. A linear correlation between N200 and P300 latency in control and patients groups was found. Conclusion: In summary, ERPs analysis in the evaluation of CI showed a great importance of long use of the device in addiction to an early time of implant.

Combined Effects of Electroacupuncture and Behavioral Training on Learning-Memory Ability and Event-Related Potential P300 in Rats with Mid/Advanced Cerebral Infarction

Background： The effectiveness of the combination of electroacupuncture （EA） and behavioral training （BT） for mid/advanced cerebral infarction （M/ACI） and related mechanisms remains unclear. This study aimed to investigate the combined effects on the learning-memory ability and event-related potential P300 in rats with M/ACI. Methods： Eighty rats with M/ACI were divided into Group Model （M）, Group EA, Group BT, and Group EA-BT （n = 20） according to the random number with five healthy rats in Group Control （CON）. On the 6th week after modeling, EA, BT, and EA-BT were given to Group EA, Group BT, and Group EA-BT, respectively, whereas Group M and Group CON were not given any intervention. Y-maze test and P300 were recorded before and after the intervention. Results： After intervention, the P300 latency was lower and the amplitude was higher in the Group EA-BT, Group EA, and Group BT than before （for latency, t = -7.638, -4.334, and -5.916; for amplitude, t = 8.125, 3.846, and 5.238; P 〈 0.01 ）, with Group EA-BT superior to Group EA （for latency, t = -3.708; for amplitude, t = 3.653; P 〈 0.01） and Group BT （for latency, t = -2.067; for amplitude, t = 2.816; P 〈 0.05）, with no significant difference between Group BT and EA （for latency, t = -1.439; for amplitude, t = 1.075; P 〉 0.05）. While the performances of Y-maze tests in the Group EA-BT, Group EA, and Group BT were all better than before （t = 10.359, 4.520, and 7.791, P 〈 0.01）, with Group EA-BT better than Group EA （t = 5.627, P 〈 0.01 ） and Group BT （t = 2.913, P 〈 0.01 ） respectively, and Group BT better than Group EA （t = 2.912, P 〈 0.01）. Conclusion： EA or BT can affect P300 in rats with M/ACI, and the combination of these two methods can significantly improve the learning-memory ability.

P240的语义距离效应

通过视觉呈现汉语双字词,在词汇决定实验中操纵启动词和目标词的语义距离,得到了一个对语义加工敏感的P240成分,它在头皮中央偏左的部位较早出现,头皮右侧的P240虽然出现较晚,但波幅较大,它可能是一种与汉语语义加工有关的新的ERP成分。

Clinical Study on Treatment of Senile Vascular Dementia by Acupuncture

63 patients with senile vascular dementia were randomly divided into the treatment group (treated by acupuncture) and the control group (treated with piracetam). The authors observed the changes in the score of Hasegawa's dementia scale (HDS), p300, rheoencephalogram, topographic EEG, superoxide dismutase (SOD) activity in erythrocytes, and lipid peroxide (LPO) level in plasma before and after treatment. The statistical data showed that the total effective rate in the treatment group (80.6%) was significantly higher than that in the control group (25%), and the differences in the observed indexes before and after treatment were significant (P 0.05), indicating that the acupuncture treatment was superior in immediate therapeutic effect on senile vascular dementia to drug treatment.