Potencial de disparidad o Mismatch negativity y P3a en pacientes con esquizofrenia / Mismatch negativity and P3a in patients with Schizophrenia

Resumen Antecedentes: la esquizofrenia es una enfermedad crónica que genera gran discapacidad, para la cual se han reportado biomarcadores potenciales, pero sin suficiente validez clínica. El mismatch negativity (MMN) y el P3a son potenciales relacionados con eventos que han demostrado ser indicadores neurofisiológicos del procesamiento auditivo pre-atencional y potenciales biomarcadores. Objetivo: evaluar el MMN y P3a en pacientes con diagnóstico de esquizofrenia y su relación con variables sociodemográficas y clínicas. Método: estudio cuantitativo transversal de 23 sujetos con esquizofrenia (ESQ) y 22 controles sanos (SN). Las amplitudes promedio y latencias del MMN/P3a para la condición infrecuente en duración y frecuencia fueron obtenidas mediante un paradigma oddball auditivo en un EEG de 32 canales. Resultados: se encontraron diferencias para la condición frecuencia en la amplitud del MMN (p=0.046; CI 95% 0.009; 0.87) y la amplitud del P3a (p=0.042; CI 95% 0.025; 1.24) entre los grupos; la amplitud del MMN fue menor en el grupo ESQ (-0.36 DE 0.51 µV) en comparación con los participantes del grupo de SN (-0.81 DE 0.89 µV), mientras que la amplitud del P3a fue menor en el grupo SN (0.18 DE 0.97 µV) versus el grupo ESQ (0.82 DE 1.05 µV). En relación con las variables sociodemográficas y clínicas, las asociaciones con el P3a fueron moderadas y con el MMN débiles. Conclusiones: la reducción de la amplitud del MMN a la condición frecuencia exhibe mayor utilidad que el P3a como medida de alta estabilidad en pacientes con esquizofrenia, lo que reitera su posible uso como biomarcador.

Abstract Background: schizophrenia is a chronic disease that generates great disability, which currently has potential biomarkers but without sufficient clinical validity. Mismatch negativity (MMN) and P3a are event-related potentials that have been shown to be neurophysiological indicators of pre-attentional auditory processing and potential biomarkers. Objective: to evaluate MMN and P3a in patients with a diagnosis of schizophrenia and their relationship with sociodemographic and clinical variables. Method: a quantitative cross-sectional study of 23 subjects with schizophrenia and 22 healthy controls was performed. The average amplitudes and latencies of the MMN/P3a for the condition infrequent in duration and infrequent in frequency were obtained using an auditory oddball paradigm on a 32-channel EEG. Results: differences were found for the frequency condition in the amplitude of the MMN (p=0.046; 95% CI 0.009; 0.87) and the amplitude of the P3a (p=0.042; 95% CI 0.025; 1.24) between the groups; MMN amplitude was lower in schizophrenia (-0.36 SD 0.51 µV) compared to healthy controls (-0.81 SD 0.89 µV), while P3a amplitude was lower in healthy controls (0.18 SD 0.97 µV) versus the group with schizophrenia (0.82 SD 1.05 µV). In regard to sociodemographic and clinical variables, the associations with P3a were moderate, and showed weak MMN. Conclusions: MMN amplitude reduction to the frequency condition exhibits greater utility than P3a as a measure of high stability in schizophrenia, restating its potential use as a biomarker.

Factors Influencing Speech Perception in Noise, and Auditory and Cognitive Training in the Elderly (review) / 中国康复理论与实践

The elderly are more likely to have difficulty in communicating in noise, regardless of hearing loss. The decline of speech perception ability in noise is the main manifestation of the decline of central auditory processing ability. Hearing and cognition are significantly correlated with central auditory processing. The mechanisms of interaction among them are common cause, reduction-compensation hypothesis, information degradation hypothesis, sensory deprivation hypothesis and cognitive load hypothesis. In short, central auditory processing is clearly related with cognition, which decreases with age. The sensory input of degradation (hearing loss or communication in noise) brings more loads to the cognitive system, occupies more cognitive resources and affects the immediate processing of cognition. Over time, chronic sensory deprivation causes an overall decline in cognitive ability. Cognitive decline in turn affects the compensatory effect on perception from top to down, thereby affecting central auditory processing ability. After confirming the mutual relations between them, the effects of auditory and cognitive training on speech resolution in noise were explored. A number of studies have confirmed that the hearing training programs can improve central auditory processing and cognitive function in patients with hearing loss, and cognitive training can be trained part of the cognitive domain (memory) to improve cognition and auditory perception.

Association between Frontal-Executive Dysfunction and Speech-in-Noise Perception Deficits in Mild Cognitive Impairment

BACKGROUND AND PURPOSE: Speech-in-noise perception deficits have been demonstrated in patients with mild cognitive impairment (MCI). However, it remains unclear whether the impairment of speech perception varies between MCI subtypes. The purpose of this study was twofold: 1) to compare speech perception performance among MCI subgroups, and 2) to identify the cognitive domains specifically related to speech-in-noise perception. METHODS: We studied 46 patients with MCI and 39 hearing-threshold-matched cognitively normal elderly (CNE) subjects. Two different patient classifications were used: 1) patients with amnestic mild cognitive impairment (aMCI) (n=21) or nonamnestic mild cognitive impairment (naMCI) (n=25), and 2) patients with frontal-executive dysfunction (FED) (n=16) or without FED (n=30). All of the subjects underwent audiometric, neuropsychological, and speech perception assessments. Speech-in-noise perception was measured using sentence recognition tests in the presence of two types of background noise at four levels. RESULTS: First, as the level of background noise increased, the MCI with FED group scored lower than both the MCI without FED and CNE groups under both types of noise. Second, both the naMCI and aMCI groups scored lower than the CNE group, but there were no differences between the naMCI and aMCI groups in sentence recognition under any noise conditions. Third, significant correlations were found between sentence recognition and executive function scores both in the MCI groups and in the CNE group. CONCLUSIONS: Our findings suggest that frontal-executive function is strongly related to speech-in-noise perception and that MCI patients with FED have greater deficits in speech-in-noise perception compared to other subgroups of MCI.

Study of event-related potentials in school-age children with cleft palate / 口腔疾病防治

Objective @#To investigate possible functional disorders of central auditory processing and language in school-age children with cleft palate through an assessment of the characteristics of the P300 and N400 event-related potentials (ERPs). @*Methods @# This study included 28 school-age children with cleft palate, aged 6 to 12 years, and 30 children without cleft palate as a control group. The P300 and N400 ERPs were selected as indexes of the central auditory processing and language functions of children in both groups. The data were statistically compared between the two groups.@*Results @#Compared with the controls, the children with cleft palate showed a significantly prolonged P300 latency (331.73 ± 14.94 ms vs. 348.64 ± 14.66 ms, P < 0.05) and a significantly decreased P300 amplitude (13.47 ± 2.24 μV vs. 12.07 ± 2.46 μV, P < 0.05). Similarly, the N400 latency of children with cleft palate was significantly prolonged compared to that of controls (431.07 ± 17.90 ms vs. 408.23 ± 18.04 ms, P < 0.05), and the N400 amplitude was significantly decreased compared to that of controls (13.75 ± 2.12 μV vs. 15.17 ± 2.34 μV, P < 0.05). @* Conclusion@#School-age children with cleft palate may have central auditory processing disorders and language dysfunctions.

The Influencing Factors of Competing Sentences Test in the Normal-hearing Adults / 听力学及言语疾病杂志

Objective To study the influencing factors of the competing sentences test in normal-hearing adults, in order to provide references for the preparation of the competing sentences test with children and the development of the diagnostic tools of the central auditory processing disorders.Methods According to the three kinds of test tables of semantic competition, sentence constituent competition and phonetic competition for the competing sentences test, the 2×3×3 factors mixed experimental design were used to test the 48 normal-hearing adults(forty-six right-handed adults and two left-handed adults) with the competing sentences test.The correct rate was obtained and the influencing factors were analyzed.Results ①The average correct rate of the Competing Sentences Test for the forty-six right-handed normal-hearing adults was 94.98%,and for the two left-handed normal-hearing adults was 96.12%.②The right-handed subjects'' right ear accuracy rate was significantly higher than that of the left ear(P0.05)with the right-handed subjects.④For the results of three types sentences,the correct rate of semantic competition was the highest, the second was the sentence constituent competition and phonetic competition was the lowest with the right-handed subjects.Conclusion No gender factors were found to affect the results of the competing sentences test among adults.The normal-hearing right-handed adults have the right ear advantage in the competing sentences test, prompting us to become concerned about the choice of the ear sides.Different competition types of sentences will have a greater impact on the difficulty of the competing sentences test, so we should pay more attention to this in the preparation of competitive sentences test tables.

Effects of an Auditory Lateralization Training in Children Suspected to Central Auditory Processing Disorder

BACKGROUND AND OBJECTIVES: Central auditory processing disorder [(C)APD] refers to a deficit in auditory stimuli processing in nervous system that is not due to higher-order language or cognitive factors. One of the problems in children with (C)APD is spatial difficulties which have been overlooked despite their significance. Localization is an auditory ability to detect sound sources in space and can help to differentiate between the desired speech from other simultaneous sound sources. Aim of this research was investigating effects of an auditory lateralization training on speech perception in presence of noise/competing signals in children suspected to (C)APD. SUBJECTS AND METHODS: In this analytical interventional study, 60 children suspected to (C)APD were selected based on multiple auditory processing assessment subtests. They were randomly divided into two groups: control (mean age 9.07) and training groups (mean age 9.00). Training program consisted of detection and pointing to sound sources delivered with interaural time differences under headphones for 12 formal sessions (6 weeks). Spatial word recognition score (WRS) and monaural selective auditory attention test (mSAAT) were used to follow the auditory lateralization training effects. RESULTS: This study showed that in the training group, mSAAT score and spatial WRS in noise (p value≤0.001) improved significantly after the auditory lateralization training. CONCLUSIONS: We used auditory lateralization training for 6 weeks and showed that auditory lateralization can improve speech understanding in noise significantly. The generalization of this results needs further researches.

Analysis of inferior colliculus region typical proteins in auditory pathway / 中国耳鼻咽喉头颈外科

OBJECTIVE To study the proteome of inferior colliculus and determinate the region-typical proteins which may be the candidate cause of the Central Auditory Processing Disorders. METHODS The telencephalon was taken as reference, and then identified and quantified the proteome of IC of adult rats with iTRAQ. Those with higher abundance in inferior colliculus than the other three regions were considered as IC-Region typical proteins,which may lead to functional specializations. RESULTS We identified 1937 cytomembrane proteins in total, among which there are 53 IC-Region typical proteins, which may lead to functional specializations of inferior colliculus.We used GO and KEGG pathway to analyze these proteins and then found that these proteins mainly take part in the regulation of neurons development and information integrations. CONCLUSION Our quantitative comparison of inferior colliculus has revealed two candidate proteins, including CaMKII and SV2A, which may play important roles in maintaining the balance of excitatory and inhibitory transmitters release. These proteins may be the candidate proteins for Central Auditory Processing Disorders.

Changes in Central Auditory Processing in Patients with Mesial Temporal Lobe Epilepsy after Anterior Temporal Lobectomy with Amygdalohippocampectomy

BACKGROUND AND PURPOSE: This study aimed to determine the effects of anterior temporal lobectomy with amygdalohippocampectomy (ATL-AH) on central auditory processing (CAP) in patients with mesial temporal lobe epilepsy with hippocampal sclerosis (mTLE-HS), and to identify factors that may contribute to the postoperative worsening of CAP. METHODS: Frequency-pattern, duration-pattern, and dichotic tests were performed before and after epilepsy surgery in 22 patients with normal hearing according to pure-tone audiometry. RESULTS: No significant difference in CAP scores was detected between pre- and postoperative tests, but there was a strong association between surgery in the language-dominant temporal lobe and postoperative worsening in the non-dominant-side dichotic test (p<0.05). The probability of a decreased performance in a non-dominant-side dichotic test after surgery was 7.5-fold greater in patients who underwent surgery on the dominant temporal lobe compared with the nondominant temporal lobe. No significant association of postoperative worsening in CAP with the verbal, nonverbal intelligence quotient, or right- or left-side lobectomy was noted. CONCLUSIONS: These results suggest that ATL-AH on the dominant side in patients with mTLE-HS worsens the CAP ability in the non-dominant-side dichotic test.

Avances en corteza auditiva / Advances in auditory cortex

El sistema auditivo nos permite detectar e interpretar las señales acústicas del medio ambiente y así modificar nuestro comportamiento. En humanos la corteza auditiva se ubica en el giro temporal superior del lóbulo temporal. Esta corteza presenta una organización estructural y funcional característica, que se ha identificado en muchas especies de mamíferos. Las áreas de organización de la corteza auditiva son: (i) una región central denominada corteza auditiva primaria o core, que corresponde al primer nivel de procesamiento, cuyas características cito-arquitectónicas y funcionales principales son poseer una capa IV prominente y presentar una organización tonotópica especular. Además, (ii) una región circundante conocida como cinturón o belt, que corresponde a las cortezas secundarias que participan de la localización espacial y reconocimiento del sonido, como también en el procesamiento del habla. Por último, (iii) las áreas de asociación auditiva integran la información auditiva con la de otros sistemas sensoriales. En este artículo se revisan las bases neuroanatómicas y las propiedades funcionales de la corteza auditiva, las que constituyen pilares fundamentales para el desarrollo de métodos diagnósticos y terapéuticos del procesamiento auditivo central.

The auditory system allows us to detect and interpret the acoustic signals of the environment and thus change our behavior. In humans, the auditory cortex is located in the superior temporal gyrus of the temporal lobe. This cortex has a characteristic structural organization and functionality that have been identified in many mammalian species. The auditory cortex has different organizational areas: (i) a core called "primary auditory cortex," which corresponds to the first level of processing, and its cyto-architectural and physiological main features are to present a prominent layer IV and to display a mirror-tonotopic organization. In addition, (ii) a surrounding region known as belt that corresponds to the secondary auditory cortices and participates in the location and recognition of sound, as well as in speech processing. Finally, (iii) auditory association areas that integrate auditory information with other sensory systems. In this article, the neuroanatomical bases and functional properties of auditory cortex processing are reviewed. These topics constitute the foundations for the development of diagnostic tools and therapeutic procedures of central auditory processing.

Right cerebral hemisphere and central auditory processing in children with developmental dyslexia / El hemisferio cerebral derecho y el procesamiento auditivo central en ninos con dislexia del desarrollo

Objective We hypothesized that if the right hemisphere auditory processing abilities can be altered in children with developmental dyslexia (DD), we can detect dysfunction using specific tests. Method We performed an analytical comparative cross-sectional study. We studied 20 right-handed children with DD and 20 healthy right-handed control subjects (CS). Children in both groups were age, gender, and school-grade matched. Focusing on the right hemisphere’s contribution, we utilized tests to measure alterations in central auditory processing (CAP), such as determination of frequency patterns; sound duration; music pitch recognition; and identification of environmental sounds. We compared results among the two groups. Results Children with DD showed lower performance than CS in all CAP subtests, including those that preferentially engaged the cerebral right hemisphere. Conclusion Our data suggests a significant contribution of the right hemisphere in alterations of CAP in children with DD. Thus, right hemisphere CAP must be considered for examination and rehabilitation of children with DD. .

Objectivo Examinamos si las habilidades del procesamiento auditivo central (PAC) del hemisferio derecho se encuentran alteradas en niños con dislexia del desarrollo (DD), por medio de pruebas específicas. Método Realizamos un estudio comparativo transversal. Estudiamos 20 niños diestros con DD y 20 niños controles (C) sanos. Los niños de ambos grupos fueron pareados por edad, género y grado escolar. Utilizamos varias pruebas para medir alteraciones del PAC, tales como: determinación de patrones de frecuencia; duración del sonido; reconocimiento de tono musical e identificación de sonidos ambientales, enfatizando la contribución del hemisferio derecho. Comparamos los resultados entre los niños con DD y C. Resultados Los niños con DD mostraron menores puntuaciones que los C en todas las subpruebas del PAC, incluyendo aquellas que involucran preferencialmente al hemisferio cerebral derecho. Conclusión Los datos obtenidos sugieren una contribución significativa del hemisferio derecho para producir alteraciones del PAC en niños con DD. Por lo tanto, las PAC que involucran al hemisferio derecho deben ser consideradas en la evaluación y rehabilitación de niño s con DD. .

Medio militar y trastornos auditivos inducidos por ruido / The military environment and noise-induced hearing impairments

En el medio militar el personal se ve sometido a los más altos niveles de ruido; se considera que las detonaciones de las armas de fuego superan en intensidad a todos los ruidos industriales. Este trabajo pretende abordar los factores de riesgo y vulnerabilidad asociados a la exposición al ruido en el ambiente militar, los aspectos más actuales relacionados con la lesión auditiva inducida por ruido y su protección. Se realizó una revisión de los artículos más representativos mediante la base de datos Medline e Hinari, se empleó para la búsqueda y creación de la bibliografía el gestor personal de referencias bibliográficas Procite, referencias al tema en revistas, tesis y referencias en Internet mediante el buscador Google. Los resultados reafirman la vulnerabilidad del personal militar a padecer algún tipo de lesión del aparato auditivo inducida por ruido, originado por los niveles de ruido elevado que se producen en el medio militar, la necesidad de enfocar de forma multidisciplinaria este tipo de lesiones y la importancia de implementar sistemas de protección auditiva eficientes, con el fin de elevar la calidad de vida de los expuestos a ruido y evitar que se produzca la discapacidad auditiva, considerando que la mejor opción es su prevención.

Extremely high noise levels are characteristic of the military environment. Firearm detonations are considered to exceed the intensity of any industrial noise. The paper approaches the risk factors and vulnerabilities associated with exposure to noise in the military environment, as well as the most recent notions about noise-induced hearing injury and hearing protection. A review was conducted of the most representative papers on the topic using databases Medline and Hinari. Bibliography lists were searched for and created using Procite personal bibliographic reference manager. Google search engine was used to find references to the topic in journals, theses and Internet references. Results confirm the vulnerability of military personnel to suffer from noise-induced hearing injuries resulting from the high noise levels occurring in the military environment, the need to approach such injuries in a multidisciplinary manner, and the importance of implementing efficient hearing protection systems, with a view to improving the quality of life of persons exposed to noise and preventing hearing impairment, based on the certainty that prevention is always the best option.

Correlación de los resultados de la prueba VE-SSW con el rendimiento escolar en niños de tercer año de enseñanza básica del Liceo Miguel Rafael Prado de la comuna de Independencia, Santiago: Chile / Correlation between SSW-SV test results and third grade children's school performance from the elementary school

Una prueba dicótica para la evaluación del procesamiento auditivo central (PAC), es la Staggered Spondaic Word versión en español (VE-SSW), que clasifica las alteraciones en cuatro categorías lo que favorece la prescripción de una terapia. El objetivo de este trabajo fue establecer correlación entre los resultados de la prueba VE-SSW y el rendimiento escolar del año 2006 en niños de tercer año básico de una escuela subvencionada de la Región Metropolitana. Se incluyeron 93 niños con audición periférica normal, de ambos géneros, entre 7 y 8 años de edad, cuyos padres autorizaron la participación de sus hijos mediante la firma de un consentimiento informado y los niños asintieron. A cada niño se le realizó otoscopía, audiometría tonal (entre 125 Hz y 8.000 Hz), logoaudiometría, impedanciometría y prueba VE-SSW. De acuerdo a los resultados, se concluyó que existe una asociación significativa entre la categoría decodificación fonémica y las calificaciones en las asignaturas de lenguaje y comunicación, inglés, educación matemática y educación artística. Los niños que están con esta categoría alterada obtuvieron calificaciones más bajas en los ramos señalados. No se encontró asociación entre las otras categorías y las calificaciones del resto de las asignaturas, aunque hubo asociaciones entre algunas condiciones auditivas o patrones de respuesta con algunas asignaturas. Poder determinar correlación entre los resultados de la prueba VE-SSW y el rendimiento escolar serviría para proponer estrategias de terapia y orientar a los profesores para que el niño con trastornos en el PAC tenga más posibilidades de mejorar sus habilidades académicas.

A dichotic test to evaluate Central Auditory Processing (CAP) labeled Staggered Spondaic Word Test Spanish version (VE-SSW), classify alteration between 4 categories, its make easy to prescribe an appropriate therapy. The aim of this job was to establish correlation between the results of the VE-SSW and the school performance during 2006, in children from third degree of basic school in the Metropolitan area in Santiago. Ninety three children with normal hearing were included, belonging to both gender, whose parents authorized their participation through a signature in the informed consent and their childreen agreed. Each child was undergoing to an otoscopy, pure tone audiometry (between 125 Hz and 8000 Hz), speech audiometry, impedance and SSW-E Test. According to results, it was concluded that exists a significant correlation between the category phonemic decodification and qualifications of the subject language and communication, English, mathematics education and art education. Children with alteration in this category obtained lower qualification in those subjects. It was not found association between other categories and qualification in the rest of the subjects, although there was association between some hearing conditions or response pattern with some subjects.To determine there is a correlation between SSW-VE test and school performance could be useful to propose therapy strategies and orientation for teachers so children, with disorders of CAP, would have more possibilities to improve their academic abilities.

Diseño y validación de un instrumento de tamizaje de habilidades auditivas / Design and validation of a screen Instrument for hearing skills

El procesamiento de información auditiva es un complejo sistema interrelacionado de mecanismos biológicos, fisiológicos y psicológicos, aspectos que permiten el desarrollo del lenguaje, el aprendizaje y la socialización. Este mecanismo implica habilidades tales como la detección, la discriminación, la identificación-reconocimiento y la comprensión. En el ambiente escolar se hace necesario conocer de forma rápida y eficaz el estado de estas habilidades, lo que motivó al equipo investigador el diseño y validación de un instrumento tamiz de fácil aplicación en niños de 3 a 12 años. La presente investigación de tipo descriptivo, utilizó el método de diseño y construcción de instrumentos. La evidencia de validez a partir de la evaluación de jueces expertos arrojó valores entre 0.7 y 1.0 (índice de kappa) y a partir del pilotaje de dicho instrumento se realizaron los ajustes pertinentes. Finalmente se puede concluir que dicha herramienta permite la identificación de las habilidades auditivas de la población para la que fue construida.

Auditory information processing is a complex interrelated system of biological, physiological and psychological mechanisms, factors that enable humans to receive, transduce and understanding acoustic information from environment, aspects that enable the development of language, learning and socialization. This mechanism involves skills such as detection, discrimination, identification, recognition and understanding. In the school environment is necessary to know quickly and effectively the status of these skills, which led to the design and validation of an instrument screen is easy to apply in children 3 to 12 years. This descriptive research used the method of design and construction of instruments. The validation of content by kappa index showed a p value result between 0.7 and 1.0, construct validation through implementation of a pilot, said the need to make minor adjustments to the instrument and found that the instrument allows the identification of listening skills of the population.

Effect of auditory training on the middle latency response in children with (central) auditory processing disorder

The purpose of this study was to determine the middle latency response (MLR) characteristics (latency and amplitude) in children with (central) auditory processing disorder [(C)APD], categorized as such by their performance on the central auditory test battery, and the effects of these characteristics after auditory training. Thirty children with (C)APD, 8 to 14 years of age, were tested using the MLR-evoked potential. This group was then enrolled in an 8-week auditory training program and then retested at the completion of the program. A control group of 22 children without (C)APD, composed of relatives and acquaintances of those involved in the research, underwent the same testing at equal time intervals, but were not enrolled in the auditory training program. Before auditory training, MLR results for the (C)APD group exhibited lower C3-A1 and C3-A2 wave amplitudes in comparison to the control group [C3-A1, 0.84 µV (mean), 0.39 (SD - standard deviation) for the (C)APD group and 1.18 µV (mean), 0.65 (SD) for the control group; C3-A2, 0.69 µV (mean), 0.31 (SD) for the (C)APD group and 1.00 µV (mean), 0.46 (SD) for the control group]. After training, the MLR C3-A1 [1.59 µV (mean), 0.82 (SD)] and C3-A2 [1.24 µV (mean), 0.73 (SD)] wave amplitudes of the (C)APD group significantly increased, so that there was no longer a significant difference in MLR amplitude between (C)APD and control groups. These findings suggest progress in the use of electrophysiological measurements for the diagnosis and treatment of (C)APD.

The Application of Diagnostic Tools of Central Auditory Processing Disorder and Their Normative Value in Each Age Group in Korean / 대한이비인후과학회지

BACKGROUND AND OBJECTIVES: To develop and apply a diagnostic test tool for central auditory processing disorder (CAPD) and to obtain normative data of Korean subjects with normal hearing. SUBJECTS AND METHOD: After obtaining the approvement of the Institution Review Board of Asan Medical Center for this clinical study, we conducted this study for 135 subjects with normal hearing. Frequency & duration pattern tests and dichotic test were administered to subjects with normal hearing were evaluated by pure tone audiometry. Patients were separated into the following age categories:up to and including 7-year-olds, 8- and 9-year-olds, 10- and 11-year-olds, 12- to 18-year-olds and adults over 18. RESULTS: The frequency pattern test showed that the mean score was 14.4+/-7.1, 19.7+/-9.2, 23.8+/-8.6, 24.1+/-7.0 and 28.5+/-2.7, for each age category, respectively. The duration pattern test showed that the mean score was 13.8+/-6.2, 17.0+/-6.1, 21.6+/-5.4, 25.6+/-4.3 and 28.4+/-2.1, respectively. The dichotic test showed that the right mean scores were 26.5+/-3.2, 27.0+/-3.2, 27.8+/-3.2, 29.4+/-0.9, 27.9+/-1.5 and left the mean scores 26.4+/-3.7, 27.0+/-2.6, 28.6+/-1.4, 28.6+/-1.3, 27.9+/-1.6 for each age category, respectively. CONCLUSION: We obtained the normative data of Korean subjects for the diagnosis of CAPD. Additional diagnostic tools and treatment methods must be developed continuously.

Electrophysiologic Assessment of Central Auditory Processing by Auditory Brainstem Responses in Children with Autism Spectrum Disorders

In addition to aberrant features in the speech, children with Autism Spectrum Disorder (ASD) may present unusual responses to sensory stimuli, especially to auditory stimuli. We investigated the auditory ability of children with ASD by using Auditory Brainstem Responses (ABR) as they can directly judge both hearing status and the integrity of auditory brainstem pathways. One hundred twenty-one children (71: ASD; M 58/ F 13, mean age; 41.8 months, 50: control group; M 41/ F 9, mean age; 38 months) were induded in the study. As compared with the values in the control group, the latency of wave V, wave I-V, and wave III-V inter-peak latencies were significantly prolonged (p<0.05) in the ASD group. The findings indicate that children with ASD have a dysfunction or immaturity of the central auditory nervous system. We suggest any children with prolonged III-V inter-peak latencies, especially high functioning children should be further evaluated for central auditory processing to set up a more appropriate treatment plan.