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.

The Effects of Monaural Stimulation on Frequency-Following Responses in Adults Who Can Sing in Tune and Those Who Cannot

Abstract Introduction Musicians have an advantage over non-musicians in detecting, perceiving, and processing nonverbal (i.e., environmental sounds, tones and others) and verbal sounds (i.e., consonant, vowel, phrases and others) as well as instrumental sounds. In contrast to the high skill of musicians, there is another group of people who are tone-deaf and have difficulty in distinguishing musical sounds or singing in tune. These sounds can originate in different ways, such as a musical instrument, orchestra, or the human voice. Objectives The objective of the present work is to study frequency-following responses (FFRs) in individuals who can sing in-tune and those who sing off-tune. Methods Electrophysiological responses were recorded in 37 individuals divided in two groups: (i) control group (CG) with professional musicians, and (ii) experimental group (EG) with non-musicians. Results There was homogeneity between the two groups regarding age and gender. The CG had more homogeneous responses in the latency of the FFRs waves when responses between the right and left ears were compared to those of the EG. Conclusions This study showed that monaural stimulation (right or left) in an FFR test is useful for demonstrating impairment of speech perception in individuals who sing off tune. The response of the left ear appears to present more subtlety and reliability when identifying the coding of speech sound in individuals who sing off tune.

Effects of transcranial magnetic stimulation on the swallowing and brain-stem auditory evoked potentials of dysphagic stroke survivors / 中华物理医学与康复杂志

Objective:To observe any effects of contralateral repeated transcranial magnetic stimulation (rTMS) of the swallowing motor cortex on the swallowing and brainstem auditory evoked potentials (BAEPs) of stroke survivors with dysphagia.Methods:A total of 83 stroke survivors with dysphagia were randomly divided into an ipsilesional stimulation group ( n=22), a contralesional stimulation group ( n=21), a bilateral stimulation group ( n=20), and a control group ( n=20). In addition to their conventional dysphagia training, those in the three stimulation groups received 3Hz rTMS while the control group was given fake stimulation. The treatment was administered daily for 20 minutes, 6 days a week, for 5 consecutive weeks. Before and after the treatment, swallowing function was assessed videofluoroscopically and using the Dysphagia Outcome and Severity Scale (DOSS). The oral and pharyngeal stages of swallowing were evaluated using the videofluoroscopic dysphagia scale (VDS). Brain stem conduction was assessed using BAEPs. Results:After treatment the average DOSS scores of all 4 groups were significantly better than before the treatment. The average DOSS scores of the contralesional and bilateral sti-mulation groups were then significantly better than those of the other two groups. The sub-item and total VDS scores of all 4 groups had decreased significantly, but the average score of the bilateral stimulation group was significantly lower than the control group′s average. Ipsilesional stimulation significantly improved the VDS sub-item scores for the triggering of pharyngeal swallowing, laryngeal elevation, and pharyngeal transit time compared with the control group. In the contralesional stimulation group the average total score and the VDS sub-item scores for apraxia, premature bolus loss, oral transit times, the triggering of pharyngeal swallowing, vallecular residue, laryngeal elevation, coating on the pharyngeal wall, and pharyngeal transit time were significantly lower than those of the control group, on average. After the treatment the latencies of BAEP waves I, III and V and the I-III, III-V and I-V interpeak intervals had decreased significantly in all four groups, but the average latencies and intervals of the bilateral and contralesional groups were significantly shorter than those of the control group. The latencies and intervals of the bilateral stimulation group were then significantly shorter than those in the ipsilesional stimulation group on average. The average latency of wave V in the bilateral stimulation group (6.53±0.73ms) was significantly shorter than that in the contralesional stimulation group after the treatment.Conclusion:Bilateral rTMS over the swallowing motor cortex combined with conventional dysphagia training can significantly improve the swallowing of dysphagic stroke survivors.

Comparative study of brainstem auditory evoked responses in females having premenstrual symptoms with normal population

Background: Premenstrual symptoms (PMS) have largely been ignored, because ages so present study are done in females specifically having PMS comparing with females with no PMS. Very little work has been done in past in this field, because females revealing menstrual history are a big taboo in our society. Aim and Objective: The aim of this study was to study brainstem auditory evoked potential (BAEP) in females having premenstrual symptoms and comparing it with females having no premenstrual symptoms. Materials and Methods: BAEP was conducted on 60 females age group of 18–40 years in two groups in Research laboratory, Department of Physiology, Lala Lajpat Rai Memorial Medical College in collaboration with SVBP Hospital, Meerut for 6 months. The subjects were divided into two groups, Group A having premenstrual symptoms and Group B having no premenstrual symptoms. The test was conducted in later part of luteal phase 23rd–25th day of menstrual cycle. The absolute latencies (ALs) and interpeak latencies (IPLs) were the parameters measured for the analysis of BAEP. Results: IPL, that is, interpeak latencies I–III and III–V in age group 18–25 years, showed statistically significant decrease in luteal phase in females having premenstrual syndrome (PMS) as compared to normal cycling females. Conclusion: Premenstrual symptoms females are showing few significant changes in auditory responses at mid brain level as recorded by BAEP study which can be due to the modulatory effect of female gonadal hormones progesterone and estrogen on neurotransmitters (serotonin, gamma-aminobutyric acid, and glutamate) in central nervous system.

Brain stem auditory evoked potential response in neonates after recovery from hyperbilirubinemia: A neurophysiological approach to screening neuronal hearing loss

Objectives: Neonatal hyperbilirubinemia leads to neurological damages including encephalopathy and hearing loss. This study aimed to screen and evaluate the hearing loss in neonates after recovery from hyperbilirubinemia using the Brainstem evoked response audiometry (BERA) test. Materials and Methods: This cross-sectional comparative study was conducted in Physiology Department at Chitwan Medical College, Nepal. It included 20 age and sex-matched neonates recently recovered from hyperbilirubinemia and 20 normal healthy controls. The external acoustic canals of subjects were checked for any blockage or collapse before BERA testing. The BERA recordings were performed after the neonate’s natural sleep following a standard lab protocol explained by Taylor’s Evoked Potential in Clinical Testing. Results: The BERA wave latencies were delayed with a higher number of case group neonates I (IL-75%, IR-80%), III (IIIL-70%, III R-80%), and V (VL- 80%, VR-85%) than those of controls. The percentage of neonates with delayed interwave latencies was comparable between groups. The neonate’s hearing sensitivity assessed using the grades of hearing impairment by WHO revealed slight (threshold of hearing left ear [THL]-25% and threshold of hearing right ear [THR]-30%) and moderate (THL-40% and THR-35%) grades among cases whereas no impairment (THL-60% and THR-55%) in controls. The hearing thresholds were more in cases. Conclusion: The auditory pathway is highly sensitive to elevated serum bilirubin. BERA detects even a minute degree of hearing damage seen after complete treatment of hyperbilirubinemia. Therefore, BERA is a helpful tool in the early screening of hearing impairment in neonates. This improves prognosis by early management so that the neurosensory systems develop to their full extent and one can enjoy a normal social life.

Brainstem auditory evoked potential combined with high resolution cranial base CT can optimize the diagnosis of auditory nerve injury / 中华创伤杂志(英文版)

PURPOSE@#Auditory nerve injury is one of the most common nerve injury complications of skull base fractures. However, there is currently a lack of auxiliary examination methods for its direct diagnosis. The purpose of this study was to find a more efficient and accurate means of diagnosis for auditory nerve injury.@*METHODS@#Through retrospectively analyzing the results of brainstem auditory evoked potential (BAEP) and high-resolution CT (HRCT) in 37 patients with hearing impairment following trauma from January 1, 2018 to July 31, 2020, the role of the two inspection methods in the diagnosis of auditory nerve injury was studied. Inclusion criteria were patient had a clear history of trauma and unilateral hearing impairment after trauma; while exclusion criteria were: (1) severe patient with a Glasgow coma scale score ≤5 because these patients were classified as severe head injury and admitted to the intensive care unit, (2) patient in the subacute stage admitted 72 h after trauma, and (3) patient with prior hearing impairment before trauma. According to Goodman's classification of hearing impairment, the patients were divided into low/medium/severe injury groups. In addition, patients were divided into HRCT-positive and negative groups for further investigation with their BAEP results. The positive rates of BEAP for each group were observed, and the results were analyzed by Chi-square test (p < 0.05, regarded as statistical difference).@*RESULTS@#A total of 37 patients were included, including 21 males and 16 females. All of them were hospitalized patients with GCS score of 6-15 at the time of admission. The BAEP positive rate in the medium and severe injury group was 100%, which was significantly higher than that in the low injury group (27.27%) (p < 0.01). The rate of BEAP positivity was significantly higher in the HRCT-positive group (20/30, 66.7%) than in the HRCT-negative group (1/7, 14.3%) (p < 0.05). Twenty patients (54.05%) were both positive for BEAP and HRCT test, and considered to have auditory nerve damage. Six patients (16.22%) were both negative for BEAP and HRCT test, and 10 patients (27.03%) were BAEP-negative but HRCT-positive: all the 16 patients were considered as non-neurological injury. The rest 1 case (2.70%) was BAEP-positive but HRCT-negative, which we speculate may have auditory nerve concussion.@*CONCLUSION@#By way of BAEP combining with skull base HRCT, we may improve the accuracy of the diagnosis of auditory nerve injury. Such a diagnostic strategy may be beneficial to guiding treatment plans and evaluating prognosis.

Study of P50 sensory gating deficit in schizophrenic patients with violent and aggressive behaviors / 四川精神卫生

ObjectiveTo assess the specificity of P50 auditory-evoked potential in schizophrenic patients with violent and aggressive behaviors， so as to provide objective biological markers for predicting violent behaviors of schizophrenic patients. MethodsA total of135 schizophrenic patients who met the diagnostic criteria of the International Classification of Diseases， tenth edition （ICD-10） were divided into aggressive group （n=70） and non-aggressive group （n=65） according to the assessment results of the Modified Overt Aggression Scale （MOAS）， meantime， another 60 healthy individuals matched for age and gender were set as healthy group. Then the P50 auditory-evoked potentials of all selected individuals were measured using EP/EMG system （MEB-9200， Nihon Kohden， Japan）. ResultsAmp S2 of the aggressive group was significantly higher than those of the non-aggressive group and healthy control group， with statistical differences ［（9.86±6.04）μV vs. （7.06±3.88）μV， P=0.004； （9.86±6.04）μV vs. （7.82±3.87）μV， P=0.031］. The proportion of S2/S1 ratio ≥0.5 was 72.88%， 43.86% and 30.00% in aggressive group， non-aggressive group and healthy group， which was the highest in aggressive group， with statistical differences （P<0.01）. The amplitude difference of P50 （S1-S2） of the aggressive group was lower than those of the non-aggressive group and the healthy control group， the differences were of statistical significance ［（4.35±9.39）μV vs.（9.89±8.48）μV， P=0.001； （4.35±9.39）μV vs.（13.42±9.81）μV， P<0.01］. ConclusionThe violent and aggressive behaviors in schizophrenic patients may be related to the sensory gating deficit.

Cortical auditory-evoked potential as a biomarker of central auditory maturation in term and preterm infants during the first 3 months

OBJECTIVES: To analyze central auditory maturation in term and preterm infants during the first 3 months of life by comparing the latency and amplitude of cortical auditory-evoked potential at different frequencies. METHODS: In this study, 17 term and 18 preterm infants were examined; all had tested positive on the neonatal hearing screening test. Cortical auditory potential was investigated during the first and third months of life. The response of the cortical auditory-evoked potential was investigated at frequencies of 500, 1000, 2000, and 4000 Hz. The latency and amplitude of the cortical response were automatically detected and manually analyzed by three researchers with experience in electrophysiology. The results were compared using analysis of variance and the Bonferroni test. A significance level of 5% was used for all analyses. RESULTS: Latency values of cortical auditory-evoked potential in the first month of birth were significantly higher than those in the third month, and latency values of the preterm group were higher than those of the term group, regardless of the frequency and time of evaluation. In general, the latency of the cortical auditory-evoked potential was higher at high frequencies. Amplitude values in the third month of life were significantly higher than those in the first month for term and preterm infants. CONCLUSION: Central auditory maturation was observed in both groups but with different results between those born at term and preterm, with latencies of cortical auditory-evoked potential higher for the preterm group and at high frequencies.

Long-term Effects of Unilateral and Bilateral Otitis Media and Myringotomy on Long-Latency Verbal and Non-Verbal Auditory-Evoked Potentials

Abstract Introduction Otitis media (OM) is considered one of the most common reasons patients seek medical care in childhood. The fluctuating nature of hearing loss in cases of OM leads to irregular sound stimulation of the central auditory nervous system. Objectives To analyze the long-latency auditory-evoked potential (LLAEP) by verbal and nonverbal sounds in children with a history of OM in the first six years of life. Methods A total of 106 schoolchildren participated in the study, 55 females and 51 males, aged between 8 and 16 years, who were divided into 3 groups: the control group (CG), the bilateral experimental group (BEG), and the unilateral experimental group (UEG). All children underwent a complete audiological evaluation (audiometry, logoaudiometry and immitance testing) and an electrophysiological evaluation (LLAEP with toneburst stimulus - LLAEP-TB, and LLAEP with speech stimulus - LLAEP-S). Results Both study groups (BEG and UEG) presented a statistically lower performance (p < 0.005) when compared with the CG regarding all of the electrophysiological tests with the prolongation of the latency values and decrease in the amplitude values: LLAEP-TB (BEG: latency - N1, P2, N2 [females] and P300, amplitude - N1 and P2), LLAEP-S (BEG: latency - P2 and N2 [females], amplitude - P2 /UEG: latency - P2 and P300, amplitude: N1 and P2). Conclusion Children who had suffered secretory OM in the first six years of life and who had undergone myringotomy for the placement of a ventilation tube, either unilaterally or bilaterally, presented worse performance in their electrophysiological responses to verbal and nonverbal LLAEPs.

Brainstem Auditory Evoked Potentials in infants aged 1 to 24 months during a hearing health care service

OBJECTIVES: Assessing infants' hearing is of utmost importance, as hearing at this phase is required for the development of oral language. Through hearing, human beings are capable of developing communication. The Brainstem Auditory Evoked Potentials are an indispensable test to diagnose deafness in infants. This study aimed to analyze the results of the Brainstem Auditory Evoked Potentials in children with risk factors for hearing loss. METHODS: This cross-sectional study analyzed the Brainstem Auditory Evoked Potentials in 123 infants aged 1 to 24 months at a hearing health care service. The Vivosonic Integrity V500 equipment, which enabled the child to be awake while the testing was carried out, was used in this study. The data were compared by gestational age and sex, according to the standards suggested in the equipment handbook. RESULTS: A significant difference was verified for age ranges 4 to 6 months, 13 to 15 months (waves I and V), and 7 to 9 months (wave V). The lower values in absolute wave latencies were comparable to data from the equipment handbook, justifying the need for standardization of the screening process. CONCLUSION: There are some differences between the standards in the equipment handbook and those observed in our study. These results will serve as a reference for the standardization of the equipment used in the hearing health care service.

Mismatch Negativity in Children: Reference Values

Abstract Introduction The Mismatch Negativity (MMN) auditory evoked potential evaluation is a promising procedure to assess objectively the ability of auditory discrimination. Objective To characterize the latency and amplitude values of MMN in children with normal auditory thresholds and without auditory complaints. Methods Children between 5 and 11 years old participated in the present study. All participants underwent acoustic immittance measurements and tonal and vocal audiometry. The MMN was recorded with the MASBE ATC Plus system (Contronic, Pelotas, RS, Brazil). The electrodes were fixed in Fz (active electrode), Fpz (ground electrode) and in M2 and M1 (references electrodes). The intensity used was 80 dBHL, the frequent stimulus was 1,000 Hz and the rare stimulus was 2,000 Hz. The stimuli were presented in both ears separately. Results For the female group, the mean latencies and amplitude of MMN were 177.3 ms and 5.01 μV in the right ear (RE) and 182.4ms and 5.39 μV in the left ear (LE). In the male group, themean latencies were 194.4 ms in the RE and 183.6ms in the LE, with an amplitude of 5.11 μV in the RE and 5.83 μV in the LE. There was no statistically significant difference between ears (p = 0.867 - latency and p = 0.178 - amplitude), age (p > 0.20) and the gender of the participants (p > 0.05). Conclusion Using the described protocol, the mean latency value of MMN was 184.0 ms for RE and 182.9 ms for LE, and the amplitude was 5.05 μV and 5.56 μV for the left and right ears, respective.

Application of N-methyl-aspartate receptor antibody level, brainstem auditory evoked potential and magnetic resonance imaging in the differential diagnosis of encephalitis in children / 中华实验和临床病毒学杂志

Objective@#To explore the clinical value of serum N-methyl-aspartate receptor (NMDAR) antibody level, brainstem auditory evoked potential (BAEP) and magnetic resonance imaging (MRI) in the differential diagnosis of viral encephalitis and anti-NMDAR encephalitis.@*Methods@#The clinical data of 68 children patients with encephalitis were retrospectively analyzed. The patients diagnosed with viral encephalitis were included in V group (n=52), and the patients diagnosed with anti-NMDAR encephalitis were included in N group (n=16). The clinical characteristics, serum NMDAR antibody level, and BAEP and MRI findings were compared between the two groups.@*Results@#The age, disease duration, abnormal behavior rate, sleep disorder rate and epileptic seizure rate in V group were significantly lower than those in N group [(6.62±1.20)Y/O vs.(8.46±1.85)Y/O, (3.53±0.71)d vs.(4.49±0.82)d, 30.77%(16/52)vs. 75.00%(12/16), 21.15%(11/52)vs. 62.50%(10/16), 26.92%(14/52)vs. 56.25%(9/16), t=4.681, t=4.560, χ2=9.882, χ2=7.958, χ2=4.701], while the abnormal rate of video EEG was significantly higher than that in N group [51.92(27/52)vs. 81.25%(13/16), χ2=4.345] (all P<0.05). There were no significant differences in gender, rates of prodromic infection symptoms, cognitive impairment, fever, headache, convulsion and incidence rate of meningeal irritation sign (P>0.05). The serum NMDAR antibody level in V group was significantly lower than that in N group [(3.40±0.69) ng/ml vs.(13.95±2.78) ng/ml t=25.319)] (P<0.05). There were no significant differences in the BAEP apparent involvement range and central auditory neurological damage between the two groups (P>0.05), but the peripheral auditory nerve damage and total BAEP abnormality rate in V group were significantly lower than those in N group [3.85%(4/104)vs. 21.88%(7/32), 6.73%(7/104)vs. 28.12%(9/32), 30.77%(16/52)vs. 62.50%(10/16), χ2=10.699, χ2=10.790, χ2=5.216] (all P<0.05). There were no significant differences in MRI signal intensity, lesion involvement range and total abnormal rate between the two groups (all P>0.05).@*Conclusions@#There were significant differences in serum NMDAR antibody level and BAEP test results among children patients with viral encephalitis or anti-NMDAR encephalitis, and they are helpful for early differential diagnosis.

Poor School Performance And Auditory Evoked Potential- A Review

Poor school performance, defined as a lower than expected academic achievement for a given age, cognitive abilities, and schooling, is complex and multifactorial. Poor school performance can result in child with low self–esteem and can cause significant stress to the parents. It is essential that cause for the poor school performance to be identified and appropriate strategy or treatment plan to be started early so that child can perform with full potential. Disorders of the auditory system affect academic performance are well known. Unlike speech and other behavioral auditory processing tests, auditory evoked potential (AEP) can be recorded regardless of a child’s developmental age or language, motivation or attention level. AEP can provide numerical data that can demonstrate central auditory nervous system maturation and, therefore can function as a biomarker of poor academic performance. Present study focuses on the researches that are done on the auditory evoked potential in poor school performance till recently

Potencial Evocado Auditivo de Tronco Encefálico com estímulos clique e Ichirp / Auditory Evoked Brain Stem Potential with click stimuli and Ichirp / Potencial Evocado Auditivo de Tronco Encefálico con estímulos clic y Ichirp

Objetivo: Analisar os traçados do Potencial Evocado Auditivo de Tronco Encefálico com o uso dos estímulos clique e o Ichirp em adultos com audição normal. Método: Trata-se de um estudo transversal, de caráter analítico, quantitativo. Foram analisados exames de Potencial Evocado Auditivo de Tronco Encefálico de 11 adultos ouvintes (2 orelhas), na faixa etária entre 20 e 25 anos, sem alterações auditivas. Esses sujeitos realizaram o registro do Potencial Evocado Auditivo de Tronco Encefálico com estímulo clique e Ichirp. O registro das latências e amplitudes da onda V foi realizado por meio do equipamento Intelligent HearingSystem ­ IHS, nas intensidades: 80, 60, 40 e 20 dB. Resultados: Não foram observadas diferenças estatisticamente significativas quanto às amplitudes da onda V, quando comparado os registros do Potencial Evocado Auditivo de Tronco Encefálico estímulo clique e do Ichirp, nas intensidades de 80 dB (p= 0.11), 60 dB (p=0.14), 40 dB (p=0.96) e 20 dB (p=0.21). Em relação às latências da onda V, foram encontradas diferenças estatísticas significantes entre os estímulos Ichirp e clique, nas seguintes intensidades: 60 dB (p=0,003) e 40 dB (p=0,016). Conclusão: Foram observadas latências maiores para o Potencial Evocado Auditivo de Tronco Encefálico com o estímulo Ichirp; contudo ausência de diferença entre as amplitudes. Houve maior facilidade na marcação da onda V com o estímulo Ichirp.

Purpose: To compare the traces of Brainstem Auditory Evoked Potential with the use of click stimuli and Ichirp in adults with normal hearing. Methods: This is a cross-sectional, analytical, quantitative study. Eleven hearing adults with ages between 20 and 25 years, with normal audiometric thresholds, totaling 22 ears were analyzed. These subjects performed the recording of the Auditory Evoked Potential of Click Brain Trunk and Ichirp. The latency and amplitude of the V wave was recorded through a computer using the Intelligent Hearing System (IHS) equipment at intensities: 80, 60, 40 and 20 dB. Results: No statistically significant differences were observed in V-wave amplitudes when compared to the Ichirp stimulus with the click, in the intensities of 80 dB (p = 0.11), 60 dB (p = 0.14), 40 dB (p = 0.96) and 20 dB P = 0.21). Regarding the latency of the V wave, significant statistical differences between the Ichirp and click stimuli were found in the following intensities: 60 dB (p = 0.003) and 40 dB (p = 0.016). Conclusion: Larger latencies were observed with the Ichirp stimulus.

Objetivo: Analizar los trazados del Potencial Evocado Auditivo de Tronco Encefálico con el uso de los estímulos clic y el Ichirp en adultos con audición normal. Método: Se trata de un estudio transversal, de carácter analítico, cuantitativo. Se analizaron exámenes de Potencial Evocado Auditivo de Tronco Encefálico en 11 adultos oyentes (2 orejas), en el grupo de edad entre 20 y 25 años, sin alteraciones auditivas. Estos sujetos realizaron el registro del Potencial Evocado Auditivo de Tronco Encefálico con estímulo clic y Ichirp. El registro de las latencias y amplitudes de la onda V fue realizado por medio del equipo Intelligent Hearing System - IHS, en las intensidades: 80, 60, 40 y 20 dB. Resultados: No se observaron diferencias estadísticamente significativas en cuanto a las amplitudes de la onda V, cuando comparados a los registros del Potencial Evocado Auditivo de Tronco Encefálico estímulo clic y Ichirp, en las intensidades de 80 dB (p = 0.11), 60 dB (p = 0.14) , 40 dB (p = 0.96) y 20 dB (p = 0.21). En cuanto a las latencias de la onda V, se encontraron diferencias estadísticas significativas entre los estímulos Ichirp y el clic, en las siguientes intensidades: 60 dB (p = 0,003) y 40dB (p = 0,016). Conclusión: Fueron observadas latencias mayores para el Potencial Evocado Auditivo de Tronco Encefálico con el estímulo Ichirp; sin embargo, ausencia de diferencia entre las amplitudes. Hubo mayor facilidad en la marcación de la onda V con el estímulo Ichirp.

Acoustic Features and Cortical Auditory Evoked Potentials according to Emotional Statues of /u/, /a/, /i/ Vowels

BACKGROUND AND OBJECTIVES: Although Ling 6 sounds are often used in the rehabilitation process, its acoustic features have not been fully analyzed and represented in cortical responses. Current study was aimed to analyze acoustic features according to gender and emotional statuses of core vowels of Ling 6 sounds, /u/, /a/, and /i/. Cortical auditory evoked potentials (CAEPs) were also observed in those vowels. SUBJECTS AND METHODS: Vowel sounds /u/, /a/, and /i/ out of Ling 6 sounds representing low, middle and high frequencies were recorded from normal 20 young adults. The participants watched relevant videos for 4-5 minutes in order for them to sympathize emotions with anger (A), happiness (H), and sadness (S) before producing vowels. And without any emotional salience, neutrally production was performed. The recording was extracted for 500 ms to select pure vowel portion of production. For analysis of CAEP, the latencies and amplitudes of P1, N1, P2, N2, N1-P2 were analyzed. RESULTS: Intensities of /u/, /a/, and /i/ were 61.47, 63.38, and 60.55 dB. The intensities of neutral (N), H, A, S were 60.60, 65.43, 64.21, and 55.75 dB for vowel /u/, vowel /a/ were 61.80, 68.98, 66.50, and 56.23 dB, and vowel /i/ were 59.34, 64.90, 61.90, and 56.05 dB. The statistical significances for vowel and emotion were found but not for gender. The fundamental frequency (F0) of vowels for N, A, H, and S were 168.04, 174.93, 182.72, and 149.76 Hz and the first formant were 743.75, 815.59, 823.32, and 667.62 Hz. The statistical significance of F0 was found by vowel, emotion, and gender. The latencies and amplitudes of CAEP components did not show any statistical significance according to vowel. CONCLUSIONS: Ling 6 sounds should be produced consistently in the rehabilitation process for considering their difference of intensities and frequencies according to speaker’s emotions and gender. The vowels seemed to be interpreted as tonal stimuli for CAEP components of this study with similar acoustic features among them. Careful selection of materials is necessary to observe meaningful conclusion of CAEP measurement with vowel stimuli.

Potenciais evocados auditivos de curta e longa latência em indivíduos com disfunção vestibular / Short- and long-latency auditory evoked potentials in individuals with vestibular dysfunction

RESUMO Objetivo Avaliar a via auditiva em nível de tronco encefálico e cortical em indivíduos com disfunção vestibular periférica. Método Participaram do estudo 19 indivíduos, com idade entre 20 e 80 anos que possuíam exames vestibulares sugestivos de Disfunção Vestibular Periférica Deficitária (DVPD) ou Disfunção Vestibular (DV). Os participantes realizaram avaliação da via auditiva por meio dos Potenciais Evocados Auditivos de Tronco Encefálico (curta latência) e dos potenciais P1, N1, P2, N2 e P300 (longa latência). Resultados Nove indivíduos apresentaram diagnóstico de Disfunção Vestibular e 10 de Disfunção Vestibular Periférica Deficitária. A média geral dos potenciais de longa latência dos participantes ficou dentro da normalidade e no de curta latência houve uma média aumentada na latência das ondas III e V da orelha esquerda, bem como no intervalo interpico I-III de ambas as orelhas. Ao relacionar os potenciais auditivos com DV e DVPD, houve significância estatística apenas no intervalo interpico III-V no potencial de curta latência da orelha direita. Ao comparar longa e curta latência nos grupos, houve diferenças nas latências entre DV e DVPD, sem significância estatística. Conclusão Não houve relação significativa de DV e DVPD com os potenciais auditivos, porém, nos potenciais de longa latência, os indivíduos com Disfunção Vestibular apresentaram maior latência em P1, N1, P2, N2 e os indivíduos com Disfunção Vestibular Periférica Deficitária, maior latência no P300. No potencial de curta latência, houve um aumento nas latências absolutas no grupo Disfunção Vestibular e nos intervalos interpicos em Disfunção Vestibular Periférica Deficitária.

ABSTRACT Purpose Evaluate the auditory pathway at the brainstem and cortical levels in individuals with peripheral vestibular dysfunction. Methods The study sample was composed 19 individuals aged 20-80 years that presented exam results suggestive of Peripheral Vestibular Disorder (PVD) or Vestibular Dysfunction (VD). Participants underwent evaluation of the auditory pathway through Brainstem Auditory Evoked Potentials (BAEP) (short latency) and P1, N1, P2, N2, and P300 cortical potentials (long latency). Results Nine individuals presented diagnosis of VD and 10 participants were diagnosed with PVD. The overall average of the long latency potentials of the participants was within the normal range, whereas an increased mean was observed in the short latency of waves III and V of the left ear, as well as in the I - III interpeak interval of both ears. Association of the auditory potentials with VD and PVD showed statistically significant correlation only in the III - V interpeak interval of the right ear for short latency. Comparison between the long and short latencies in the groups showed differences between VD and PVD, but without statistical significance. Conclusion No statistically significant correlation was observed between VD/PVD and the auditory evoked potentials; however, for the long latency potentials, individuals with VD presented higher latency in P1, N1, P2, and N2, where as participants with PVD showed higher latency in P300. In the short latency potentials, there was an increase in the absolute latencies in the VD group and in the interpeak intervals in the PVD group.

Study of brainstem auditory evoked potentials in children with Bell's palsy / 中国小儿急救医学

Objective To evaluate the function of auditory nerve and brainstem in children with Bell's palsy by using brainstem auditory evoked potential ( BAEP) . Methods A retrospective study was car-ried in total of 69 patients with Bell's palsy admitted in the pediatric department of Shengjing Hospital of China Medical University from January 2017 to January 2018. There were 33 males and 36 females,aged 1 to 12 years old. Sixty healthy children served as control group. BAEP were determined in 69 patients and 60 healthy subjects. EEG and CT or MRI of brain were performed to exclud tumor,intracranial infection and so on. The patients in the case group were divided into 2 groups:1-3 years old group (38 cases) and 4-12 years old group (31 cases). Sixty healthy children were also divided into 2 groups:1-3 years old group (30 cases) and 4-12 years old group (30 cases). Results The hearing threshold was normal in the children of the control group. There was no significant difference not only in potential latency but also internal potential latency of BAEP between right and left ear. The abnormal rate of BAEP was 39. 1％ ( 27/69 ) in case groups,19 cases of them recovered(70. 4％,19/27) after 2 weeks of clinical treatment. Another 8 patients re-covered after 2 months. The abnormality rate of EEG was 5. 8％ (4/69),and the abnormality rate of CT or MRI in head was 14. 5％ (10/69). Both were nonspecific changes. In the two groups,Ⅰ-Ⅲinternal potential latency was significantly shortened ( P <0. 05 ) , and Ⅲ-Ⅴinternal potential latency was significantly pro-longed (P<0. 05)respectively,between the normal side and abnormal side. There were significant differences in the Ⅲ potential latency(P<0. 05),Ⅰ-Ⅲinternal potential latency (P<0. 01),and Ⅲ-Ⅴ internal poten-tial latency ( P <0. 01 ) respectively, between pretherapy and post-treatment. Conclusion Bell's palsy of children could cause abnormal of auditory nerve conduction,and BAEP could find the electro physiologic ab-normality in nervous system,and guide clinical intervention.

Noise attenuation analysis on auditory evoked potential based on maximum length sequence / 生物医学工程学杂志

The maximum length sequence (m-sequence) has been successfully used to study the linear/nonlinear components of auditory evoked potential (AEP) with rapid stimulation. However, more study is needed to evaluate the effect of the m-sequence order in terms of the noise attenuation performance. This study aimed to address this issue using response-free electroencephalogram (EEG) and EEGs with nonlinear AEPs. We examined the noise attenuation ratios to evaluate the noise variation for the calculations of superimposed averaging and cross-correlation, respectively, which constitutes the main process in the deconvolution method using the dataset of spontaneous EEGs to simulate the cases of different orders (order 5 to 12) of m-sequences. And an experiment using m-sequences of order 7 and 9 was performed in true cases with substantial linear and nonlinear AEPs. The results demonstrate that the noise attenuation ratio is well agreed with the theoretical value derived from the properties of m-sequences on the random noise condition. The comparison of waveforms for AEP components from two m-sequences showed high similarity suggesting the insensitivity of AEP to the m-sequence order. This study provides a more comprehensive solution to the selection of m-sequences which will facilitate the feasible application on the nonlinear AEP with m-sequence method.

Temporal processing and long-latency auditory evoked potential in stutterers / Processamento temporal e potencial evocado auditivo de longa latência em indivíduos gagos

Abstract Introduction: Stuttering is a speech fluency disorder, and may be associated with neuroaudiological factors linked to central auditory processing, including changes in auditory processing skills and temporal resolution. Objective: To characterize the temporal processing and long-latency auditory evoked potential in stutterers and to compare them with non-stutterers. Methods: The study included 41 right-handed subjects, aged 18-46 years, divided into two groups: stutterers (n = 20) and non-stutters (n = 21), compared according to age, education, and sex. All subjects were submitted to the duration pattern tests, random gap detection test, and long-latency auditory evoked potential. Results: Individuals who stutter showed poorer performance on Duration Pattern and Random Gap Detection tests when compared with fluent individuals. In the long-latency auditory evoked potential, there was a difference in the latency of N2 and P3 components; stutterers had higher latency values. Conclusion: Stutterers have poor performance in temporal processing and higher latency values for N2 and P3 components.

Resumo Introdução: A gagueira é um distúrbio da fluência da fala e pode estar associada a fatores neuroaudiológicos ligados ao processamento auditivo central, entre eles as alterações das habilidades auditivas de processamento e resolução temporal. Objetivo: Caracterizar o processamento temporal e o potencial evocado auditivo de longa latência em indivíduos gagos e compará-los com indivíduos sem gagueira. Método: Participaram do estudo 41 indivíduos destros, de 18 a 46 anos, distribuídos em dois grupos: 20 com gagueira e 21 sem gagueira, comparados segundo idade, escolaridade e gênero. Todos os indivíduos foram submetidos aos testes de padrão de duração, teste de identificação de intervalos aleatórios e o potencial evocado auditivo de longa latência. Resultados: Indivíduos com gagueira apresentaram pior desempenho nos testes de padrão de duração e Random Gap Detection, quando comparados com os indivíduos fluentes. No potencial evocado auditivo de longa latência, houve diferença na latência dos componentes N2 e P3, os indivíduos gagos apresentaram maiores valores de latência. Conclusão: Os indivíduos com gagueira apresentaram processamento temporal com desempenho abaixo do esperado e um maior valor de latência para os componentes N2 e P3.

Application of brainstem auditory evoked potentials in diagnosis of brain death / 中国中西医结合急救杂志

Objective To evaluate the diagnostic validity of application of brainstem auditory evoked potential (BAEP) as an ancillary test in patients with brain death.Methods A prospective observational study was conducted. Adult patients (≥ 18 years) with brain death were consecutively admitted to the Department of Intensive Care Unit (ICU) of Beijing Tiantan Hospital Affiliated to Capital Medical University from July 2015 to June 2017, and they further underwent BAEP monitoring. The following findings: absence of all waveforms at bilateral sides, absence of all waveforms except wave-Ⅰonly present at bilateral orunilateral side were set as the positive criteria of BAEP for the diagnosis of brain death, and its diagnostic sensitivity (SEN), positive predictive value (PPV) and false negative rate (FNR) were further assessed.Results A total of 47 patients were enrolled in the study, and the 43 complete BAEP results were analyzed. The SEN, PPV and FNR of the above 3 types of diagnostic criteria (absence of all waveforms, and unilateral or bilateral presence of wave-Ⅰ only) were 100% [95% confidence interval (95%CI) 90-100], 100% (95%CI 89-100), and 0% (95%CI 0-9), respectively.Conclusion As an ancillary test, BAEP has extremely high validity for the diagnosis of patients with brain death, thus it should be used more extensively in clinical practice.