The P300 Auditory Evoked Potential in Cochlear Implant Users: A Scoping Review

Abstract Introduction The P300 auditory evoked potential is a long-latency cortical potential evoked with auditory stimulation, which provides information on neural mechanisms underlying the central auditory processing. Objectives To identify and gather scientific evidence regarding the P300 in adult cochlear implant (CI) users. Data Synthesis A total of 87 articles, 20 of which were selected for this study, were identified and exported to the Rayyan search software. Those 20 articles did not propose a homogeneous methodology, which made comparison more difficult. Most articles (60%) in this review compare CI users with typical hearing people, showing prolonged P300 latency in CI users. Among the studies, 35% show that CI users present a smaller P300 amplitude. Another variable is the influence of the kind of stimulus used to elicit P300, which was prolonged in 30% of the studies that used pure tone stimuli, 10% of the studies that used pure tone and speech stimuli, and 60% of the studies that used speech stimuli. Conclusion This review has contributed with evidence that shows the importance of applying a controlled P300 protocol to diagnose and monitor CI users. Regardless of the stimuli used to elicit P300, we noticed a pattern in the increase in latency and decrease in amplitude in CI users. The user's experience with the CI speech processor over time and the speech test results seem to be related to the P300 latency and amplitude measurements.

Neurophysiology in between the interests of Dom Pedro II of Brazil, and Charles Brown-Séquard (Historical Note) / Neurofisiologia entre os interesses de Dom Pedro II do Brasil e Charles Brown-Séquard (Nota Histórica)

This article presents our historical research regarding Charles Brown-Séquard, a famous scientist with important contributions to the medical field, in particular for neurology, and endocrinology, and his relationship with Dom Pedro II, the second and last Brazilian Emperor, and an enlightened ruler. The Emperor contacted several illustrious personages in support of State policy, such as for the development of experimental physiology at the Imperial Museum of Natural History, but also for personal purposes given his health problems and those of the Empress. Charles Brown-Séquard and his pilgrimage between different worlds as a physician and physiologist are presented until his definitive establishment in Paris, where he replaces Claude Bernard in the chair of experimental medicine at the Collège de France. Jacques-Arsene d'Arsonval took over after this chair, and together with Brown-Séquard, he electrophysiologically examined the Emperor's diabetic peripheral neuropathy. In this article, the Emperor´s relationship with Brown-Séquard was studied mainly from the correspondence sent to Dom Pedro II and retrieved from the Imperial Museum in Petrópolis, Brazil, and from the accounts of his meetings that included scientific sessions and clinical consultations. This article can be used to understand the progress of knowledge in the field of neurology/clinical neurophysiology, the tracking of emerging ideas in the field of science in the past and the threat to the credibility of researchers.

Este artigo apresenta nossa pesquisa histórica a respeito de Charles Brown-Séquard, famoso cientista com importantes contribuições para a área médica, em especial para a neurologia e endocrinologia, e sua relação com Dom Pedro II, segundo e último Imperador brasileiro, e governante esclarecido. O Imperador contactou várias personalidades ilustres no apoio à política de Estado, como para o desenvolvimento da fisiologia experimental no Museu Imperial de História Natural, mas também para fins pessoais dados os seus problemas de saúde e os da Imperatriz. Charles Brown-Séquard e sua peregrinação entre diferentes mundos como médico e fisiologista são apresentados até seu estabelecimento definitivo em Paris, onde substitui Claude Bernard na cadeira de medicina experimental no Collège de France. Jacques-Arsene d'Arsonval assumiu após esta cadeira e, juntamente com Brown-Séquard, examinou eletrofisiologicamente a neuropatia periférica diabética do imperador. Neste artigo, a relação do Imperador com BrownSéquard foi estudada principalmente a partir da correspondência enviada a Dom Pedro II e recuperada no Museu Imperial de Petrópolis, Brasil, e dos relatos de seus encontros que incluíam sessões científicas e consultas clínicas . Este artigo pode ser usado para entender o progresso do conhecimento no campo da neurologia/neurofisiologia clínica, o rastreamento de ideias emergentes no campo da ciência no passado e a ameaça à credibilidade dos pesquisadores.

The Effect of Different Stimulation Rates on Brainstem Auditory-Evoked-Potential Responses

Abstract Introduction Auditory-evoked potentials are influenced by several factors, including polarity, filter, stimulus intensity and stimulation rate. The presentation of higher rates of stimuli per second enables the collection of a greater number of responses in a given period of time, promoting a shorter testing time; however, the collected recordings are subject to changes related to wave morphology. Objectives To compare the brainstem auditory-evoked-potential responses with click stimulus with the most commonly used stimulation rates in the clinical practice. Methods The present cross-sectional analytical study was performed with fifteen participants of both genders and normal hearing thresholds. The brainstem auditoryevoked potential was performed at four different stimulation rates (21.1, 26.7, and 27.7 stimuli/s, and a rate determined based on a mathematical calculation using the a measurement of the transmission frequency of the power grid at the time of the examination). Results We observed that the rate of 21.1 stimuli/s showed the highest amplitudes for waves I, III, and V when compared with the other rates. The rate of 26.7 stimuli/s, when compared with 27.7 stimuli/s, showed a higher amplitude for wave V. The latency if wave V was significantly lower with the rate of 21.1 stimuli/s than with 27.7 stimuli/s. Conclusions The stimulation rate interferes with wave latencies and amplitudes; its decrease from 27.7 to 21.1 stimuli/s decreases the latency of wave V and increases the amplitues and improves the morphology of waves I, III and V. In addition, we found evidence that suggests an improvement in the visualization of wave III by adjusting the stimulation rate based on a measurement of the local transmission frequency of the power grid.

Standardization of Latency and Amplitude Values of Short, Middle and Long Latency Auditory Evoked Potentials in Adults

Abstract Introduction Auditory processing refers to the efficiency and effectiveness with which the central auditory nervous system uses auditory information. Middle- and long-latency auditory evoked potentials are objective electrophysiological tests that can complement the diagnosis of alterations involving central auditory processing. Objectives To standardize latency and amplitude values for short-, middle-, and long-latency auditory evoked potentials in adults with normal hearing thresholds. Methods This is a cross-sectional study. Thirty-three adults with normal hearing thresholds, without hearing complaints, and with normal central auditory processing were evaluated. All underwent basic audiological evaluation, central auditory processing assessment, and short-, middle-, and long-latency auditory evoked potentials. Results Absolute latency and interpeak values for middle- and long-latency auditory evoked potentials were lower than internationally suggested. However, for the brainstem auditory evoked potential, the means were within the range considered as normal, as suggested in the equipment. Conclusions The present study provided measurements of normal latencies and amplitudes for short-, middle-, and long-latency auditory evoked potentials in adults.

Mismatch Negativity in Children and Adolescents with Autism Spectrum Disorder

Abstract Introduction Individuals with autism spectrum disorder (ASD) have abnormalities in auditory perception and sensitivity. The mismatch negativity (MMN) component of the evoked potential demonstrates a brain detection response to an auditory change due to memory, and enables the identification of changes in the auditory system. Objectives To analyze MMN responses in children and adolescents with ASD and compare them with those of a control group. Methods Cross-sectional and comparative study. The sample was composed of 68 children and adolescents, divided into study group (SG), which contained those diagnosed with ASD, and the control group (CG), which contained those with typical development, normal hearing thresholds, and without hearing complaints. All participants were submitted to peripheral and central electrophysiological auditory evaluations. For the electrophysiological auditory evaluation and MMN recording, the electrodes were fixed in the following positions: Fz (active electrode), M1 and M2 (reference electrodes), and on the forehead (ground electrode). Auditory stimuli were presented in both ears simultaneously, with a frequency of 1,000 Hz for the frequent stimulus, and of 2,000 Hz for the rare stimulus, in an intensity of 80 dBNA. Results Latency and amplitude values were increased in the SG, with a statistically significant difference in comparison with the CG. In the MMN analysis, there was no statistically significant difference in the comparison between right and left ears and between genders. Conclusions Children and adolescents with ASD had higher latency and amplitude values in the MMN component than the individuals in the CG.

A study on variation in spatial voltage distribution pattern across tissue layers between non-excitable plant and excitable plant

Understanding the mechanism of information processing in plants remains a challenging task even in the era of machine learning and artificial neural networks. Sir J.C. Bose had demonstrated through his experiments that the various modes of stimulation which effectively initiated nervous impulse in animals led to impulse generation in the excitable plant Mimosa pudica as well. In order to localize the tissue responsible for conduction of excitation in the petiole of Mimosa, Bose had constructed a specialized ‘Electric Probe’ (glass tip electrode). From this experiment, Bose found that there were different intensities of transmitted excitation in different tissue layers of the petiole. In this backdrop, an experimental research has been conducted to comparatively study the pattern of spatial voltage distribution across different tissue layers in both, a non-excitable plant Alternanthera philoxeroides (in stem) and an excitable plant Mimosa pudica (in petiole), by following experimental principles similar to that of Sir J. C. Bose. For the present experimental study, the electrical probes (glass tip electrode), similar to the one designed by J.C. Bose and the whole experimental setup has been constructed and developed completely in the laboratory. The results indicated a striking difference in the spatial voltage distribution pattern between the non-excitable and the excitable plant. Since Mimosa is an excitable plant having specialized mechanoreceptor cells, the change in spatial voltage distribution in the different layers of petiole, following excitation (uniform electrical stimuli) of a sub-petiole has been also studied, as an additional segment of the present research. In the present study a notable difference in the intensities of the transmitted excitation was also found upon electrical stimulation of one of the sub-petioles of the excitable plant M. pudica.

Arritmias en personas transgénero / Arrhythmias in transgender individuals

Resumen La necesidad de mejorar el acceso a servicios de salud para la comunidad transgénero se ha vuelto evidente, especialmente en relación con el riesgo cardiovascular, que es más alto en comparación con la población general. Los procedimientos quirúrgicos y las terapias hormonales son comunes en esta población para reafirmar la identidad de género, pero plantean desafíos, ya que se asocian con alteraciones en el metabolismo de lípidos, la concentración de grasa corporal y la resistencia a la insulina. Además, existe un aumento en el riesgo de eventos cardiovasculares adversos, como tromboembolia venosa, accidente cerebrovascular e infarto de miocardio. La influencia de las hormonas sexuales en las propiedades electrofisiológicas del corazón ha sido estudiada, destacando diferencias entre géneros que pueden predisponer a la población transgénero a arritmias cardiacas. La terapia hormonal exógena, tanto para mujeres como para hombres trans, puede afectar el intervalo QT y aumentar el riesgo de arritmias, incluida la fibrilación auricular. Aunque la incidencia de arritmias en la población transgénero aún no está completamente clara, la evidencia sugiere la necesidad de un monitoreo cardiovascular cuidadoso y la consideración de factores de riesgo antes de iniciar terapias hormonales.

Abstract The need to improve access to health services for the transgender community has become evident, especially concerning cardiovascular risk, which is higher compared to the general population. Surgical procedures and hormone therapies are common in this population to affirm gender identity, but they pose challenges as they are associated with disruptions in lipid metabolism, body fat concentration, and insulin resistance. Additionally, there is an increased risk of adverse cardiovascular events such as venous thromboembolism, stroke, and myocardial infarction. The influence of sex hormones on the electrophysiological properties of the heart has been studied, highlighting gender differences that may predispose the transgender population to cardiac arrhythmias. Exogenous hormone therapy, for both transgender women and men, can affect the QT interval and increase the risk of arrhythmias, including atrial fibrillation. Although the incidence of arrhythmias in the transgender population is not entirely clear, evidence suggests the need for careful cardiovascular monitoring and consideration of risk factors before initiating hormone therapies.

Auditory central pathways in children and adolescents with multiple sclerosis / Sistema auditivo central em crianças e adolescentes com esclerose múltipla

Abstract Background Multiple sclerosis (MS) is an inflammatory demyelinating disease. Auditory evoked potential studies have demonstrated conduction and neural processing deficits in adults with MS, but little is known about the electrophysiological responses in children and adolescents. Objective to evaluate the central auditory pathway with brainstem auditory evoked potentials (BAEP) and long-latency auditory evoked potentials (LLAEP) in children and adolescents with MS. Methods The study comprised 17 individuals with MS, of both sexes, aged 9 to 18 years, and 17 healthy volunteers, matched for age and sex. All individuals had normal hearing and no middle ear impairments. They were assessed with click-BAEP and LLAEP through oddball paradigm and tone-burst stimuli. Results Abnormal responses were observed in 60% of electrophysiologic assessments of individuals with MS. In BAEP, 58.82% of MS patients had abnormal responses, with longer wave V latency and therefore longer III-V and I-V interpeak latencies than healthy volunteers. In LLAEP, 52.94% of MS patients had abnormal responses. Although statistical differences were found only in P2-N2 amplitude, MS patients had longer latencies and smaller amplitudes than healthy volunteers in all components. Conclusion Children and adolescents with MS had abnormal BAEP responses, with delayed neural conduction between the cochlear nucleus and the lateral lemniscus. Also, abnormal LLAEP results suggest a decrease in neural processing speed and auditory sensory discrimination response.

Resumo Antecedentes A esclerose múltipla (EM) é uma doença inflamatória desmielinizante. Estudos com potenciais evocados auditivos têm demonstrado déficits de condução e processamento neural em adultos com EM, mas pouco se sabe sobre as respostas electrofisiológicas em crianças e adolescentes. Objetivo avaliar a via auditiva central por meio dos potenciais evocados auditivos de tronco encefálico (PEATE) e dos potenciais evocados auditivos de longa latência (PEALL) em crianças e adolescentes com EM. Métodos Foram avaliados17 indivíduos com EM, de ambos os sexos, com idades entre 9 e 18 anos, e 17 voluntários saudáveis, pareados por sexo e idade. Todos os indivíduos tinham audição normal sem alterações de orelha média. Os indivíduos foram avaliados por meio do PEATE com estímulo clique e do PEALL com paradigma de oddball e estímulo tone-burst. Resultados Foram observadas alteração em 60% das avaliações dos indivíduos com EM. No PEATE, 58,82% dos pacientes com EM apresentaram alteração, com aumento da latência da onda V, e interpicos III-V e I-V aumentados em comparação aos voluntários saudáveis. No PEALL, 52,94% dos pacientes com EM apresentaram alteração. Embora diferenças estatísticas foram observadas apenas na amplitude P2-N2, os pacientes com EM apresentaram latências prolongadas e amplitudes menores em comparação aos voluntários saudáveis para todos os componentes. Conclusão Crianças e adolescentes com EM apresentaram alteração das respostas do PEATE, com atraso de condução neural entre o núcleo coclear e o lemnisco lateral. Além disso, os resultados alterados do PEALL sugeriram uma diminuição na velocidade de processamento neural e de discriminação sensorial da audição.

Does the Number of Stimuli Influence the Formation of the Endogenous Components of the Event-Related Auditory Evoked Potentials?

Abstract Introduction The number of stimuli is important to determine the quality of auditory evoked potential records. However, there is no consensus on that number in studies, especially in the sample studied. Objectives To investigate the influence of the number of rare stimuli on forming N2 and P3 components, with different types of acoustic stimuli. Methods Cross-sectional, descriptive, comparative study, approved by the ethics committee of the institution. The sample comprised 20 normal hearing adults of both sexes, aged 18 to 29 years old, with normal scores in the mental state examination and auditory processing skills. The event-related auditory evoked potentials were performed with nonverbal (1 kHz versus 2 kHz) and verbal stimuli (/BA/ versus /DA/). The number of rare stimuli varied randomly in the recordings, with 10, 20, 30, 40, and 50 presentations. Results P3 latency was significantly higher for nonverbal stimuli with 50 rare stimuli. N2 latency did not show any difference between the type and number of stimuli. The absolute P3 and N2-P3 amplitudes showed significant differences for both types of stimuli, with higher amplitude for 10 rare stimuli, in contrast with the other ones. The linear tendency test indicated significance only for the amplitude - as the number of rare stimuli increased, the amplitude tended to decrease. Conclusion The components were identifiable in the different numbers of rare stimuli and types of stimuli. The P3 and N2-P3 latency and amplitude increased with fewer verbal and nonverbal stimuli. Recording protocols must consider the number of rare stimuli.

Electrocardiographic changes and changes in cardiac lactate and troponin I levels associated with search and rescue physical activity in military dogs / Alterações eletrocardiográficas e nos níveis de lactato e troponina I cardíaca associadas à atividade física de busca e salvamento em cães militares

Rescue and recovery dogs intercalate the activity intensity developed, which also triggers significant metabolic changes in cardiac physiology. Thus, we evaluated the changes that search simulation causes in glucose, lactate, and cardiac troponin I level (cTnI) and the electrocardiographic and heart rate during the activity and recovery phase to predict the physiological adaptation to the exercise. Five healthy adult dogs from the Rescue and Recovery Service of Military Firefighters Corps were submitted to 60 minutes search operation simulation in the woods. They covered a forest area of approximately 50,000 m2. The dogs were loose and accompanied by their driver, and they could perform any physical activity. Were evaluated serum biochemical analysis of glucose, lactate, cardiac troponin I, electrocardiographic, and heart rate (rest, exercise phase, and recovery time). No changes in glucose levels, heart rate, and cardiac rhythm were detected. In comparison to baseline values, there is an increase: in lactate at the end of the exercise phase [EXER] (60'EXER), and in the recovery phase [RCT] at 30'RCT and 60'RCT, and cTnI at 60'RCT, 120'RCT, and 4hRCT. P wave duration was significantly higher at 60'EXER, 15'RCT, and 30'RCT, with no alterations in wave amplitude. QRS interval duration significantly increased at 30'RCT, and the ST segment presented a significant difference at 60'EXER, 15'RCT, and 60'RCT compared to the rest moment. The moderate alterations in lactate and cTnI and few alterations in the electrocardiographic and heart rate maintenance suggest the adaptation of rescue and recovery dogs to the type, intensity, and duration of search operation simulation performed.(AU)

Cães de busca e resgate intercalam a intensidade da atividade desenvolvida que desencadeia alterações metabólicas significativas, bem como na fisiologia cardíaca. Assim, foram avaliadas as alterações que a simulação de busca produz nos níveis de glicose, lactato, troponina I cardíaca (cTnI), bem como na frequência cardíaca e atividade eletrocardiográfica durante a fase de atividade e recuperação, a fim de predizer a adaptação fisiológica ao exercício. Cinco cães adultos saudáveis do Serviço de Resgate e Salvamento do Corpo de Bombeiros Militares foram submetidos à simulação de operação de busca de 60 minutos na mata e cobriram uma área florestal de aproximadamente 50.000 m2. Os cães estavam soltos, acompanhados pelo condutor e estavam livres para realizar qualquer tipo de atividade física. Foram avaliados os níveis séricos de glicose, lactato e troponina I cardíaca, atividade eletrocardiográfica e frequência cardíaca em repouso, na fase de exercício e no tempo de recuperação. Não foram detectadas alterações nos níveis de glicose, frequência cardíaca e ritmo cardíaco. Em comparação com os valores basais houve aumento de lactato ao final da fase de exercício [EXER] (60'EXER) e na fase de recuperação [RCT] aos 30'RCT e 60'RCT; e cTnI aos 60'RCT, 120'RCT e 4hRCT. Duração da onda P foi significativamente maior em 60'EXER, 15'RCT e 30'RCT, sem alterações na amplitude da onda. Duração do intervalo QRS teve aumento significativo em 30'RCT e o segmento ST apresentou diferença significativa em 60'EXER, 15'RCT e 60'RCT quando comparado ao basal. As alterações moderadas nos níveis de lactato e cTnI, bem como a pouca alteração na atividade eletrocardiográfica e manutenção da frequência cardíaca sugerem boa adaptação dos cães de busca e resgate ao tipo, intensidade e duração da operação de busca simulada realizada.(AU)

Occult macular dystrophy: brief literature review / Distrofia macular ocular: breve revisão da literatura

ABSTRACT Occult macular dystrophy is characterized by a slowly progressive bilateral reduction of visual acuity in patients with normal fundus and fluorescein angiography. We describe a case of a 36-year-old male patient diagnosed with this condition, after extensive investigation with multimodal imaging, electrophysiology tests, and systemic screening.

RESUMO A distrofia macular oculta é caracterizada por perda visual, lentamente progressiva, em pacientes com fundoscopia e angiografia fluoresceínica normais. Relatamos o caso de um paciente de 36 anos do sexo masculino diagnosticado com essa condição após extensa investigação com exames de imagem multimodais, eletrofisiológicos e rastreio de doenças sistêmicas.

Effects of electrophysiological technique combined with pelvic floor muscle training on the rapid recovery of urinary incontinence after electroresection of prostatic hyperplasia / 现代泌尿外科杂志

【Objective】 To investigate the clinical effects of electrophysiological technique combined with pelvic floor muscle training on urinary incontinence after electroresection of benign prostatic hyperplasia (BPH) based on the concept of enhanced recovery after surgery (ERAS). 【Methods】 A total of 86 patients with urinary incontinence treated with electroresection of BPH during Oct.2019 and Feb.2022 were randomly divided into control group and observation group, with 43 cases in either group. All patients received health education plus pelvic floor muscle training, and the observation group also received electrophysiological treatment. The differences in the indexes before and after treatment were compared between the two groups. 【Results】 There were no significant differences in the 1 h pad test, ICIQ-SF score, maximum urinary flow rate (Qmax), post void residual (PVR), International Prostate Symptom Score (IPSS), 24 h urinary incontinence frequency, and Urinary Incontinence Quality of Life Questionnaire Score (I-QoL) before treatment between the two groups (P>0.05). However, after treatment, Qmax and I-QoL score were significantly higher in the observation group than in the control group, while the other 5 indicators were significantly lower in the observation group than in the control group (all P<0.05). The total clinical effective rate was significantly higher in the observation group than in the control group (P<0.05). 【Conclusion】 Electrophysiological technique combined with pelvic floor muscle training can effectively improve the symptoms of urinary incontinence and promote the recovery of urinary control function, which is in line with the concept of ERAS and is worthy of further research and promotion.

Acupuncture intervening depressive disorder:research progress in its neurobiological mechanism / 针灸推拿医学（英文版）

Depressive disorder seriously affects people's physical and mental health.Acupuncture is a safe and effective treatment for depression,yet,its mechanism is unclear.Therefore,acupuncture's action mechanism in intervening depression was summarized from several perspectives,including morphology and ultrastructure of neurons in depression-related brain areas,function and structure of glial cells,brain functional and structural connectivity,and neuroelectrophysiology.It's discovered that acupuncture can repair the morphological and ultrastructural damage of neurons in the hippocampus and prefrontal lobe,mitigate the functional and structural injuries of glial cells in the hippocampus and prefrontal lobe,strengthen functional connectivity and heal structural connection,and promote neuroelectrophysiological activities,which possibly are the principal mechanisms of how acupuncture works in intervening depressive disorder.

Deepening the understanding of the mechanism of clinical electroretinography based on the photopic/scotopic vision of human eyes / 中华实验眼科杂志

Visual electrophysiological examination has strict standards and quantitative methods for stimulating light, which involves the concepts of photopic and scotopic vision of human eyes.Photopic vision is a visual perceptual activity mainly involving cones in a bright environment, while scotopic vision is a visual perceptual activity mainly involving rod cells in a dark environment.Even if the rated power of the light source is the same, the brightness (luminous flux) perceived by human eyes is different for different spectral light sources in the same or different visual environments.To enable ophthalmologists and clinical visual electrophysiological examination technicians to accurately understand the setting mechanism and recording results of stimulating light in the international standard of visual electrophysiology, this paper introduced the basic concepts such as the concept of human eye photopic and scotopic vision, the measurement and expression of brightness in different visual environments, and the luminous flux of light sources under photopic and scotopic vision in detail, and interpreted the application of the concept of photopic and scotopic vision in clinical visual electrophysiology.

Distinction and processing of common artifact in clinical visual electrophysiology / 中华实验眼科杂志

Objective:To explore the common causes and solutions for artifacts in clinical visual electrophysiological examination.Methods:A cross-sectional study was performed.The clinical visual electrophysiological examination results of 25 001 cases were collected from 2012 to 2020 at the Southwest Hospital/Southwest Eye Hospital, Third Military Medical University (Army Medical University). Artifacts were identified and analyzed according to the standard waveform provided by the International Society for Clinical Electrophysiology of Vision.The characteristics and causes of the artifact were analyzed.The solutions to reduce and eliminate the artifact were proposed.This study adhered to the Declaration of Helsinki.The study protocol was approved by the Ethics Committee of the Southwest Hospital/Southwest Eye Hospital, Third Military Medical University (Army Medical University) (No.KY2020053).Results:There were 60 typical artifacts identified among the 25 001 cases.Common causes of the artifacts were classified as three categories, the factors related to subjects, environment, or instruments.Among the 60 cases, 42(70.0%) were caused by tension in head and facial muscles of patients, 9(15.0%) due to blinking of patients, 4(6.7%) resulted from 50 Hz power frequency artifact, 2(3.3%) arisen from abnormal amplifier, and 3(5.0%) for other reasons.The strategies to avoid artifact were as follows.First, examiners could inform patients of the examination process in advance to help patients to relax and avoid the influencing factors, such as muscle tension in head and face, blinking, inattention and so on; second, high-quality 50 Hz hardware wave trap was recommended to reduce 50 Hz artifact, with good ground connection and removing of the high-power electrical appliances near the visual electrophysiological instrument; third, clean the skin sufficiently to reduce the reference electrode impedance to less than 1 kΩ.Conclusions:There is a variety of artifact waveforms and causes.The technicians should make correct judgments and handle the artifact in time to provide more accurate examination results.The doctors should know about artifact, which is helpful for better interpretation of visual electrophysiological examination reports.

Risk factors of bortezomib-related peripheral neuropathy and the clinical features and electrophysiological characteristics of patients during treatment of multiple myeloma / 白血病·淋巴瘤

Objective:To explore the risk factors of bortezomib-related peripheral neuropathy (BIPN) and the clinical and electrophysiological characteristics of patients in treatment of multiple myeloma (MM).Methods:The clinical data of 71 newly diagnosed MM patients treated with BD (bortezomib + dexamethasone) regimen in Yancheng First People's Hospital from March 2016 to December 2019 were retrospectively analyzed. The bone marrow morphology, immunology, cytogenetics, molecular biology (MICM), routine electrophysiological examination before and after treatment were performed. All patients were divided into the peripheral neuropathy (PN) group and the non-PN group according to the presence or not of BIPN, and the clinicopathological differences of both groups were also compared; a binary logistic regression model was used to analyze the factors affecting the occurrence of PN. The electrophysiological characteristics were summarized and fluorescence in situ hybridization (FISH) was used to detect karyotype of BIPN patients.Results:Among 71 MM patients, there were 40 cases (56.3%) of PN and 31 cases (43.7%) of non-PN. The proportion of patients at international staging system (ISS) staging Ⅲ, and the levels of IgA, IgG, IgM, serum creatinine, β 2-microglobulin (β 2-MG) in the PN group were higher than those in the non-PN group, and hemoglobin (Hb) level in the PN group was lower than that in the non-PN group, and the differences were statistically significant (both P < 0.05). Binary logistic regression analysis showed that increased IgA ( OR = 1.151, 95% CI 1.012-1.309, P = 0.033), increased IgG ( OR = 1.055, 95% CI 1.000~1.112, P = 0.049), increased IgM ( OR = 1.010, 95% CI 1.001-1.018, P = 0.022), increased serum creatinine ( OR = 1.037, 95% CI 1.011~1.065, P = 0.005), increased β 2-MG ( OR = 1.564, 95% CI 1.039-2.354, P = 0.032) were risk factors for BIPN. Among 40 patients with BIPN, 33 cases (82.5%) of sensory nerve conduction velocity (SCV) were abnormal, 23 cases (57.5%) of motor nerve conduction velocity (MCV) were abnormal; 31 cases (77.5%) showed demyelination damage, 9 cases (22.5%) had axonal damage. Among 40 patients with BIPN, 24 cases underwent FISH detection, including 19 cases (79.2%) with chromosomal mutations, of which 12 cases (50.0%) were mixed subtype abnormal. Conclusions:MM patients with high levels of β 2-MG, IgA, IgG, IgM and serum creatinine are more prone to PN when treated with bortezomib. The electrophysiology of patients with BIPN is mainly characterized by demyelination of sensory nerves.

Thalamocortical Circuit Controls Neuropathic Pain via Up-regulation of HCN2 in the Ventral Posterolateral Thalamus / 神经科学通报·英文版

The thalamocortical (TC) circuit is closely associated with pain processing. The hyperpolarization-activated cyclic nucleotide-gated (HCN) 2 channel is predominantly expressed in the ventral posterolateral thalamus (VPL) that has been shown to mediate neuropathic pain. However, the role of VPL HCN2 in modulating TC circuit activity is largely unknown. Here, by using optogenetics, neuronal tracing, electrophysiological recordings, and virus knockdown strategies, we showed that the activation of VPL TC neurons potentiates excitatory synaptic transmission to the hindlimb region of the primary somatosensory cortex (S1HL) as well as mechanical hypersensitivity following spared nerve injury (SNI)-induced neuropathic pain in mice. Either pharmacological blockade or virus knockdown of HCN2 (shRNA-Hcn2) in the VPL was sufficient to alleviate SNI-induced hyperalgesia. Moreover, shRNA-Hcn2 decreased the excitability of TC neurons and synaptic transmission of the VPL-S1HL circuit. Together, our studies provide a novel mechanism by which HCN2 enhances the excitability of the TC circuit to facilitate neuropathic pain.

Disrupted Maturation of Prefrontal Layer 5 Neuronal Circuits in an Alzheimer's Mouse Model of Amyloid Deposition / 神经科学通报·英文版

Mutations in genes encoding amyloid precursor protein (APP) and presenilins (PSs) cause familial forms of Alzheimer's disease (AD), a neurodegenerative disorder strongly associated with aging. It is currently unknown whether and how AD risks affect early brain development, and to what extent subtle synaptic pathology may occur prior to overt hallmark AD pathology. Transgenic mutant APP/PS1 over-expression mouse lines are key tools for studying the molecular mechanisms of AD pathogenesis. Among these lines, the 5XFAD mice rapidly develop key features of AD pathology and have proven utility in studying amyloid plaque formation and amyloid β (Aβ)-induced neurodegeneration. We reasoned that transgenic mutant APP/PS1 over-expression in 5XFAD mice may lead to neurodevelopmental defects in early cortical neurons, and performed detailed synaptic physiological characterization of layer 5 (L5) neurons from the prefrontal cortex (PFC) of 5XFAD and wild-type littermate controls. L5 PFC neurons from 5XFAD mice show early APP/Aβ immunolabeling. Whole-cell patch-clamp recording at an early post-weaning age (P22-30) revealed functional impairments; although 5XFAD PFC-L5 neurons exhibited similar membrane properties, they were intrinsically less excitable. In addition, these neurons received smaller amplitude and frequency of miniature excitatory synaptic inputs. These functional disturbances were further corroborated by decreased dendritic spine density and spine head volumes that indicated impaired synapse maturation. Slice biotinylation followed by Western blot analysis of PFC-L5 tissue revealed that 5XFAD mice showed reduced synaptic AMPA receptor subunit GluA1 and decreased synaptic NMDA receptor subunit GluN2A. Consistent with this, patch-clamp recording of the evoked L23>L5 synaptic responses revealed a reduced AMPA/NMDA receptor current ratio, and an increased level of AMPAR-lacking silent synapses. These results suggest that transgenic mutant forms of APP/PS1 overexpression in 5XFAD mice leads to early developmental defects of cortical circuits, which could contribute to the age-dependent synaptic pathology and neurodegeneration later in life.

O benefício do mascaramento modulado nos potenciais evocados auditivos corticais com estímulo de fala / Masking release in cortical auditory evoked potentials with speech stimulus

RESUMO Objetivo analisar o efeito do mascaramento estável e modulado no Potencial Evocado Auditivo Cortical com estímulo de fala em adultos-jovens. Método participaram 14 indivíduos com idades entre 19 e 28 anos de ambos os sexos e sem perda auditiva. O exame de Potencial Evocado Auditivo Cortical foi realizado com estímulo de fala sintética /ba/ simultâneo ao ruído Speech Shaped Noise apresentado em três condições: ruído estável com intensidade de 30 dB NPSpe (ruído estável fraco), ruído estável com intensidade de 65 dB NPSpe (ruído estável forte) e ruído modulado em intensidade de 30 dB NPSpe e 65 dB NPSpe em 25Hz e com período de modulação de 40 ms. Resultados foram observadas maiores latências nos componentes corticais, exceto P2, na condição de ruído estável forte e medidas mais robustas de amplitude dos componentes corticais P1, N1 e P2 na condição de ruído modulado com diferença estatística significativa na comparação com a condição de ruído estável forte. Houve pior morfologia na condição de ruído estável forte, quando comparado aos demais registros. Os limiares eletrofisiológicos médios para as condições de ruído estável forte e ruído modulado foram 60 dB NPSpe e 49 dB NPSpe, respectivamente, mostrando 11,7 dB de diferença média. Conclusão podemos inferir que houve um menor efeito mascarante do ruído modulado, comparado à condição de ruído estável forte, nas medidas de amplitude dos componentes corticais e uma diferença média de 11,7 dB entre os limiares eletrofisiológicos (interpretado como a medida do Benefício do Mascaramento Modulado).

ABSTRACT Purpose To analyze the effect of masking on the Cortical Auditory Evoked Potential with speech stimulus in young adults. Methods Fourteen individuals aged between 19 and 28 years of both sexes with no hearing loss participated in the study. The Cortical Auditory Evoked Potential examination was performed with synthetic speech stimulus /ba/ simultaneous to Speech Shaped Noise presented under three conditions: steady noise with a 30 dB SPLep intensity (weak steady noise), steady noise with a 65 dB SPLep intensity o (strong steady noise) and modulated noise with 30 dB SPLep and 65 dB SPLep intensities at 25Hz and modulation period of 40 ms. Results Higher latencies were observed in the cortical components, except P2, in the condition of strong steady noise and more meaningful measures of amplitude of the cortical components P1, N1 and P2 in the condition of modulated noise with statistically significant difference in comparison to the strong steady noise condition. There was worse wave morphology in the condition of strong steady noise, when compared to the other records. The average electrophysiological thresholds for the conditions of strong steady noise and modulated noise were 60 dB SPLep and 49 dB SPLep, respectively, showing a 11.7 dB mean difference. Conclusion We could infer that there was a lower masking effect of modulated noise when compared to the strong steady noise condition, in the amplitude measurements of the cortical components and an average difference of 11.7 dB between the electrophysiological thresholds (interpreted as the measure of the Masking Release).

Ocorrência de alterações nos potenciais evocados auditivos de fumantes: revisão sistemática da literatura / Occurrence of changes in the auditory evoked potentials of smokers: systematic review of the literature

RESUMO Objetivo Verificar a ocorrência de alterações nos exames de potencial evocado (PEA) auditivo em adultos fumantes normo-ouvintes. Estratégia de pesquisa Revisão sistemática da literatura de acordo com recomendações do PRISMA, buscando responder à pergunta: "Há alterações nos resultados do exame de PEA em adultos fumantes?", estratégia PECOS. Pesquisa realizada nas bases de dados PubMed, Embase, CINAHL, LIVIVO, Scopus, Web of Science, LILACS e Scielo. Busca adicional da literatura cinzenta: Google Scholar e ProQuest e busca manual das referências dos estudos incluídos. Critérios de seleção Foram selecionados estudos com delineamento transversal, sem restrição do ano de publicação e idioma. Análise dos dados Primeiramente foram analisados os títulos e resumos de todos os estudos encontrados, seguido da leitura na íntegra dos estudos elegíveis. Resultados Foram obtidos 898 artigos, que após remoção dos duplicados e análise cega por três pesquisadores, foram selecionados oito trabalhos. Grande parte dos estudos encontrou uma associação entre tabagismo ativo e alterações nos testes eletrofisiológicos. Conclusão Adultos fumantes normo-ouvintes apresentam alterações nos exames de PEA de curta e longa latência. No potencial evocado auditivo de tronco encefálico, os principais componentes alterados foram o aumento das latências das ondas I e III e nos interpicos I - III e III - V, bem como diminuição da amplitude das ondas. No Mismatch Negativity, houve aumento significativo da amplitude da onda e da latência. No potencial de longa latência, P300, houve aumento das latências e redução das amplitudes nos componentes N1 (em Fz) e P3.

ABSTRACT Purpose To verify the occurrence of abnormal auditory evoked potentials (AEP) tests in adult smokers. Research strategies Systematic review of the literature according to the PRISMA guidelines, to answer the question: "Are there any changes in the AEP results in adult smokers?", PECOS strategy. Research carried out on PubMed, Embase, CINAHL, LIVIVO, Scopus, Web of Science, LILACS and Scielo databases. Additional search of gray literature: Google Scholar and ProQuest hand searching of reference lists of the included studies. Selection criteria Cross-sectional studies were selected, without restriction on the year of publication and language. Data analysis First, the titles and abstracts of all the studies were analyzed, followed by the full reading of the eligible studies. Results 898 articles were collected, after the duplicate studies were removed and after blind analysis by three researchers, 8 studies of the observational type were selected. Most studies have found an association between active smoking and changes in electrophysiological tests. Conclusion Normal hearing adult smokers present alterations in short and long AEP. In the auditory brainstem response, the main altered components were the increase in waves latencies of I and III and in the interpeaks I - III and III - V, as well as a decrease in the amplitude of the waves. In Mismatch Negativity, there was a significant increase in wave amplitude and latency. In the long latency potential, P300, there was an increase in latencies and decreased amplitudes in the components N1 (in Fz) and P3.