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Cortical Auditory Evoked Potentials in Children with a Hearing Loss: A Pilot Study  [PDF]
Amineh Koravand,Beno?t Jutras,Maryse Lassonde
International Journal of Pediatrics , 2012, DOI: 10.1155/2012/250254
Abstract: Objective. This study examined the patterns of neural activity in the central auditory system in children with hearing loss. Methods. Cortical potentials and mismatch responses (MMRs) were recorded from ten children aged between 9 and 10 years: five with hearing loss and five with normal hearing in passive oddball paradigms using verbal and nonverbal stimuli. Results. Results indicate a trend toward larger P1 amplitude, a significant reduction in amplitude, and latency of N2 in children with hearing loss compared to control. No significant group differences were observed for the majority of the MMRs conditions. Conclusions. Data suggest that the reduced auditory input affects the pattern of cortical-auditory-evoked potentials in children with a mild to moderately severe hearing loss. Results suggest maturational delays and/or deficits in central auditory processing in children with hearing loss, as indicated by the neurophysiological markers P1 and N2. In contrast, negative MMR data suggest that the amplification provided by the hearing aids could have allowed children with hearing loss to develop adequate discriminative abilities. 1. Introduction Sensory hearing loss often affects speech perception due to a decreased audibility of the signal as well as decreased temporal analysis ability [1–3]. Studies have demonstrated the influence of hearing loss on auditory temporal ordering, a task which involves the central auditory system [4–6]. The lower performance of children with hearing loss in this task could be caused by central auditory neurophysiological deficits. Auditory neurophysiological functions have been measured in adults and children with hearing loss [7–11]. Sensory hearing loss in adults induced a delay in the latency of N1, N2, and a reduction in N2-P2 amplitude [8]. Oates et al. [7] investigated the N1, N2, MMN, and P3, presented at 65 and 80?dB?SPL, and found a latency prolongation and an amplitude reduction of these components in adults with hearing loss compared to those of the control group at both levels of presentation. However, an earlier study did not reveal any significant differences in the latencies of N1, P2, and P3 components between adults with hearing loss and their normal-hearing controls [11]. Several factors could account for these differential findings, such as participants’ age, age at onset of hearing loss, type and/or degree of hearing loss, level of stimulus presentation, and type of stimuli used. In children, latency changes in the cortical-auditory-evoked potentials (CAEPs) have been used to document auditory system
Influência dos contrastes de fala nos potenciais evocados auditivos corticais The influence of speech stimuli contrast in cortical auditory evoked potentials  [cached]
Kátia de Freitas Alvarenga,Leticia Cristina Vicente,Raquel Caroline Ferreira Lopes,Rubem Abr?o da Silva
Brazilian Journal of Otorhinolaryngology , 2013,
Abstract: Estudos voltados aos potenciais evocados auditivos com estímulos de fala em indivíduos ouvintes s o importantes para compreender como a complexidade do estímulo influencia nas características do potencial cognitivo auditivo gerado. OBJETIVO: Caracterizar o potencial evocado auditivo cortical e o potencial cognitivo auditivo P3 com estímulos de contrastes vocálico e consonantal em indivíduos com audi o normal. MéTODO: Participaram deste estudo 31 indivíduos sem altera es auditivas, neurológicas e de linguagem na faixa etária de 7 a 30 anos. Os potenciais evocados auditivos corticais e cognitivo auditivo P3 foram registrados nos canais ativos Fz e Cz utilizando-se os contrastes de fala consonantal (/ba/-/da/) e vocálico (/i/-/a/). Desenho: Estudo de coorte, transversal e prospectivo. RESULTADOS: Houve diferen a entre o contraste de fala utilizado e as latências dos componentes N2 (p = 0,00) e P3 (p = 0,00), assim como entre o canal ativo considerado (Fz/Cz) e os valores de latência e amplitude de P3. Estas diferen as n o ocorreram para os componentes exógenos N1 e P2. CONCLUS O: O contraste do estímulo de fala, vocálico ou consonantal, deve ser considerado na análise do potencial evocado cortical, componente N2, e do potencial cognitivo auditivo P3. Studies about cortical auditory evoked potentials using the speech stimuli in normal hearing individuals are important for understanding how the complexity of the stimulus influences the characteristics of the cortical potential generated. OBJECTIVE: To characterize the cortical auditory evoked potential and the P3 auditory cognitive potential with the vocalic and consonantal contrast stimuli in normally hearing individuals. METHOD: 31 individuals with no risk for hearing, neurologic and language alterations, in the age range between 7 and 30 years, participated in this study. The cortical auditory evoked potentials and the P3 auditory cognitive one were recorded in the Fz and Cz active channels using consonantal (/ba/-/da/) and vocalic (/i/-/a/) speech contrasts. Design: A crosssectional prospective cohort study. RESULTS: We found a statistically significant difference between the speech contrast used and the latencies of the N2 (p = 0.00) and P3 (p = 0.00) components, as well as between the active channel considered (Fz/Cz) and the P3 latency and amplitude values. These correlations did not occur for the exogenous components N1 and P2. CONCLUSION: The speech stimulus contrast, vocalic or consonantal, must be taken into account in the analysis of the cortical auditory evoked potential, N2 component, and aud
Middle and late latency ERP components discriminate between adults, typical children, and children with sensory processing disorders  [PDF]
Patricia L. Davies,Wen-Pin Chang,William J. Gavin
Frontiers in Integrative Neuroscience , 2010, DOI: 10.3389/fnint.2010.00016
Abstract: This study examined whether combinations of middle latency sensory evoked potential components and late components, possibly indicative of cognitive processing, can discriminate between three sample groups; 18 adults (20–55 years), 25 typical children (5–10 years) and 28 children with sensory processing disorders (SPD) (5–12 years). Electroencephalography (EEG) recordings were made while participants heard random presentations of two auditory stimuli (1 and 3 kHz) each at two intensities (50 and 70 dB). Amplitude and latency measurements were obtained for the N1, P2, N2, and P3 components from the averaged event-related potential (ERP) for each of the four auditory stimuli. Discriminant analyses revealed two functions, one which described the relationship of the components on SPD deficit continuum and one which described the relationship of these components on a developmental continuum. Together, these two functions correctly classified 90.5% of the participants as to their group membership. These results are discussed in relation to neurodevelopmental theories.
Comparison of Middle Latency Auditory Evoked Potentials in Learning Disability and Normal 7-12 Year- Old Children  [PDF]
Mahin Sedaie,Saeed Farahani,Ebrahim Pirasteh,Zahra Soleimani
Audiology , 2007,
Abstract: Background and Aim: Learning disability(LD) is one of the most prevalent problems among elementary school children. Approximately 10 percent of all elementary school children suffer from this problem. It has been determined that learning disability is predominantly accompanied with subtle impairment in central auditory nervous system. The main idea of this study was to evaluate middle latency auditory evoked potential (MLAEPs) in learning disabled children. Materials and Method: This cross-sectional study investigated middle latency auditory evoked potential in children with learning disability (n = 31) compared to normal children (n = 31). Latencies and amplitudes of MLAEPs results with different stimulus intensity and binaural stimulation were compared between two groups. Results: Compared to control group, learning disabled children exhibited smaller amplitudes for all the components except the right ear Na and Pa. There is no significant difference between two groups for latencies of the components. Conclusion: It seems that middle latency auditory evoked potential may be useful in diagnosis and evaluation of learning disabled children although more investigation is required.
Correlation Between Acoustically Evoked Short Latency Negative Response and Vestibular Evoked Myogenic Potentials in Children with Profound Sensorineural Hearing-Loss
Zahra Jafari,Saeed Malayeri,Nima Rezazadeh,Farideh HajiHeydari
Audiology , 2012,
Abstract: Background and Aim: Vestibular evoked myogenic potentials and acoustically evoked short latency negative response are two non-cochlear responses with probably saccular origin. The present study was conducted to determine the percentage of presence and the relation between these two responses in children with hearing loss.Methods: Thirty children with profound congenital sensorineural hearing loss were studied Vestibular evoked myogenic potentials ellicitedby tone burst stimuli and acoustically evoked short latency negative response ellicited by click stimuli were recorded. Both responses were recorded at air conduction threshold level monaurally via an internal receiver.Results: Vestibular evoked myogenic potentials in 53.3% of children and acoustically evoked short latency negative response in 40.0% of cases were recorded. There was a significant correlation between the percentage of recording these two responses (p=0.005). Gender and the stimulated ear had no effect on the results.Conclusion: In almost half of these disabled children, both vestibular evoked myogenic potentials and acoustically evoked short latency negative response were recoreded. This finding may both indicate that hearing loss has no effect on the function of otolith organs in some children and vestibular deficits probably exist along with hearing impairment in others. This findng reiterates the importance of evaluation of vestibular system as part of standard auditory evaluations.
Post-auricular muscle reflex in the Middle Latency Evoked Auditory Response
Matas, Carla Gentile;Neves, Ivone Ferreira;Carvalho, Flávia Macarelli de;Leite, Renata Aparecida;
Brazilian Journal of Otorhinolaryngology , 2009, DOI: 10.1590/S1808-86942009000400018
Abstract: the middle latency auditory evoked response may be influenced by the post-auricular muscle reflex which occurs at the same latency of this potential. aim: to evaluate the muscle reflex influence on the middle latency response, identifying the most appropriate place for response recording. materials and methods: prospective study in which 40 normal hearing individuals, ranging in age from 18 to 40 years old, were assessed by middle latency response with electrodes placed first on the mastoids, and then on the earlobes. results: significant statistical differences were seen between the values found with electrodes placed on the mastoids and on the earlobes concerning the na-pa amplitude in c3/a1, c3/a2 and c4/a2, concerning the na wave latency in c3/a2 and c4/a2, and concerning the pa wave latency in c3/a1 and c3/a2. we found a higher occurrence of the post-auricular reflex when the electrode was placed on the mastoids, in all studied modalities. conclusion: there was post-auricular muscle reflex interference upon the middle latency response obtained when the electrodes were placed on the mastoid, and the most efficient electrode disposition in order to capture and to register more accurately this potential was on the earlobe.
The maturational process of the auditory system in the first year of life characterized by brainstem auditory evoked potentials
Amorim, Raquel Beltr?o;Agostinho-Pesse, Raquel Sampaio;Alvarenga, Kátia de Freitas;
Journal of Applied Oral Science , 2009, DOI: 10.1590/S1678-77572009000700010
Abstract: the study of brainstem auditory evoked potentials (baep) allows obtaining the electrophysiological activity generated in the cochlear nerve to the inferior colliculus. in the first months of life, a period of greater neuronal plasticity, important changes are observed in the absolute latency and inter-peak intervals of baep, which occur up to the completion of the maturational process, around 18 months of life in full-term newborns, when the response is similar to that of adults. objective: the goal of this study was to establish normal values of absolute latencies for waves i, iii and v and inter-peak intervals i-iii, iii-v and i-v of the baep performed in full-term infants attending the infant hearing health program of the speech-language pathology and audiology course at bauru school of dentistry, brazil, with no risk history for hearing impairment. material and methods: the stimulation parameters were: rarefaction click stimulus presented by the 3a insertion phone, intensity of 80 dbnhl and a rate of 21.1 c/s, band-pass filter of 30 and 3,000 hz and average of 2,000 stimuli. a sample of 86 infants was first divided according to their gestational age in preterm (n=12) and full-term (n=74), and then according to their chronological age in three periods: p1: 0 to 29 days (n=46), p2: 30 days to 5 months 29 days (n=28) and p3: above 6 months (n= 12). results: the absolute latency of wave i was similar to that of adults, generally in the 1st month of life, demonstrating a complete process maturity of the auditory nerve. for waves iii and v, there was a gradual decrease of absolute latencies with age, characterizing the maturation of axons and synaptic mechanisms in the brainstem level. conclusion: age proved to be a determining factor in the absolute latency of the baep components, especially those generated in the brainstem, in the first year of life.
Comparison Acoustically Evoked Short Latency Negative Response with Vestibular Evoked Myogenic Potential in Adults with Profound Hearing Loss
Seyede Nazanin Hajari,Abdolreza Sheibanizadeh,Akram Pourbakht,Homa Zarrinkoub
Audiology , 2012,
Abstract: Background and Aim: A negative deflection with a 3-4 ms latency period has been reported to exist within the auditory brainstem response of some patients with profound hearing loss following a strong acoustic stimulus. This deflection, namingly the n3 or the acoustically evoked short latency negative response is assumed to be a vestibular-evoked potential, especially of saccular origin. Since the myogenic potential is also saccular in origin, the purpose of the present study was to investigate the relationship between these two tests in adults with profound hearing loss.Methods: The present cross sectional study was performed on 20 profoundly deaf volunteers(39 ears) who aged between 18-40 years old, randomly selected from available deaf adults in Tehran. The auditory brainstem response of all subjects was recorded following a 1000 Hz tone burst in 70-100dB nHL. Subjects were also tested for vestibular evoked myogenic potential.Results: Only 34 of 39 ears recorded myogenic potential that negative response was recorded in 27 of 34 ears with normal p13 and n23. In seven ears with normal p13 and n23, the negative response was absent. In 3 ears with no p13 and n23, the negative response was observed, and two none.Conclusion: In view of the high prevalance of the negative response in profoundly deaf ears with normal p13 and n23, it could be concluded that the negative response can be used when for any reason, it is not possible to record myogenic potential and be considered as a new test in vestibular test battery.
Auditory evoked potentials in peripheral vestibular disorder individuals  [cached]
Matas, Carla Gentile,Silva, Sara Manami,Wen, Débora Dong Mei,Nunes, Cristiane da Silva
International Archives of Otorhinolaryngology , 2011,
Abstract: Introduction: The auditory and vestibular systems are located in the same peripheral receptor, however they enter the CNS and go through different ways, thus creating a number of connections and reaching a wide area of the encephalon. Despite going through different ways, some changes can impair both systems. Such tests as Auditory Evoked Potentials can help find a diagnosis when vestibular alterations are seen. Objective: describe the Auditory Evoked Potential results in individuals complaining about dizziness or vertigo with Peripheral Vestibular Disorders and in normal individuals having the same complaint. Methods: Short, middle and long latency Auditory Evoked Potentials were performed as a transversal prospective study. Conclusion: individuals complaining about dizziness or vertigo can show some changes in BAEP (Brainstem Auditory Evoked Potential), MLAEP (Medium Latency Auditory Evoked Potential) and P300.
Long latency auditory evoked potentials and central auditory processing in children with reading and writing alterations: Preliminary data  [cached]
Soares, Aparecido José Couto,Sanches, Seisse Gabriela Gandolfi,Neves-Lobo, Ivone Ferreira,Carvallo, Renata Mota Mamede
International Archives of Otorhinolaryngology , 2011,
Abstract: Introduction: Presently, it is admitted that individuals with reading and writing alterations may present delay in the development of listening skills, which may interfere in the learning process. The assessment of the listening skills can occur in a behavioral way, through central auditory processing (CAP) tests, or by electrophysiological assessment highlighting the long latency auditory evoked potentials (LLAEP). The use of the LLAEP as a means of complementary assessment of individuals with reading and writing alterations can become an important data both for further characterization of the alterations, as for the therapeutic guidance of this population. Objective: Characterize the CAP and the LLAEP in children with reading and writing alterations. Method: Research approved by the Institution's Ethic Commission under no 305/10. The assessment of CAP and LLAEP was performed in 12 children aged between 8 and 12 years old (average of 10,6 years), with reading and writing alterations confirmed in specific evaluation. Results: The most altered CAP skills were temporal ordination and figure-ground for linguistic sounds. There were found altered results in P300 and in MMN. Conclusion: The individuals with reading and writing alterations performed below the expected on CAP tests. The MMN allowed a better characterization of the auditory function of this population. There was evidence of association between the CAP results and the alteration of the LLAEP.
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