This study utilized paired tones at 1000 Hz with a 500 ms interpair interval and a 10 s interstimulus interval to assess sensory gating. Forty-two participants, ranging from 3-72 years of age were used to observe maturational changes in amplitude, latency, and suppression ratios of the P50 waveform. Previous research has shown that in normal adults the amplitude in response to the second of the paired tones is significantly suppressed compared to the amplitude in response to the first tone. The current study showed amplitude decreased with age to middle adulthood, where it increased slightly to later adulthood. Latencies decreased with age. Suppression ratios decreased from childhood to adolescence, with an increase from early adulthood to later adulthood. Sensory gating would appear to be a later developing aspect of human sensory physiology. Also similar to many other brain functions, sensory gating decreases in later adulthood.

O implante coclear tem sido considerado uma opção de reabilitação em pacientes com a Desordem do Espectro da Neuropatia Auditiva. Contudo, a sua indicação é relativamente recente, e, com isso, poucos estudos investigaram o desenvolvimento cortical nestes pacientes. Até o momento, não há estudos longitudinais que caracterizem o desenvolvimento do sistema auditivo central após a ativação do implante coclear. O objetivo deste trabalho foi caracterizar o componente P1 do potencial evocado auditivo cortical nos primeiros meses de uso do implante coclear em crianças com a Desordem do Espectro da Neuropatia Auditiva. Participaram deste estudo oito crianças diagnosticadas com Desordem do Espectro da Neuropatia Auditiva, com perda auditiva pré-lingual de grau severo ou profundo e usuárias de implante coclear. A pesquisa do potencial evocado auditivo cortical foi realizada com o estímulo de fala /da/, apresentado em campo livre, em três sessões de avaliação: na ativação dos eletrodos, com três e com seis meses após a ativação do implante coclear. Os registros obtidos foram analisados pela pesquisadora e por um juiz experiente em eletrofisiologia a fim de verificar a concordância das análises. Houve concordância de 100% (Kappa=1) entre os juízes quanto à ocorrência do componente P1, com coeficiente de correlação interclasse excelente para os valores de latência e amplitude. Quanto à morfologia, o componente P1 caracterizou-se como um pico positivo robusto na primeira sessão de avaliação. O componente P1 foi registrado em 71,43% da casuística na primeira sessão, em 87,50 % na segunda e em 85,71% na terceira sessão de avaliação. Nos pacientes em que foi possível observar o componente P1 em todas as sessões de avaliação, observou-se uma redução da latência considerando o primeiro e último momento de avaliação, contudo, os resultados mostraram-se heterogêneos entre as crianças avaliadas. Assim, na pesquisa do componente P1 do potencial evocado auditivo cortical, não foi possível determinar um padrão de comportamento deste componente em crianças com a Desordem do Espectro da Neuropatia Auditiva nos seis primeiros meses de uso do implante coclear. / Cochlear implants have been considered a rehabilitation option in patients with auditory neuropathy spectrum disorder. However, their indication is relatively recent, thus, few studies have investigated cortical development in these patients. So far, no longitudinal study has characterized the development of the central auditory system, following cochlear implant activation. This study aimed at characterizing P1 cortical auditory evoked potential in the first months of cochlear implant use, in children presented with auditory neuropathy spectrum disorder. Eight children diagnosed with auditory neuropathy spectrum disorder, with severe or profound pre-lingual hearing loss, users of cochlear implant, participated in this study. The cortical auditory evoked potential research was performed with the /da/ speech stimulus presented in free field, in three assessment sessions: at electrodes activation, at three and at six months, following cochlear implant activation. The recordings obtained were analyzed by the researcher and by an experienced electrophysiologist, so as to verify the agreement of the analyses. There was 100% agreement (Kappa=1) between the referees, as to the occurrence of component P1, with an excellent interclass correlation coefficient for latency and amplitude values. Regarding morphology, P1 was characterized as a robust positive peak in the first assessment session, being recorded in 71.43% of the sample, in the first session, in 87.50%, in the second, and in 85.71%, in the third. In patients in whom it was possible to observe P1 in all assessment sessions, a latency reduction was observed, considering the first and last time of evaluation, nevertheless, the results were shown to be heterogeneous among the children assessed. Thus, in the P1 cortical auditory evoked potential research, it was not possible to determine a behavior pattern of this component in children presented with auditory neuropathy spectrum disorder, in the first six months of cochlear implant use.

O redirecionamento das estruturas auditivas centrais em pacientes que foram submetidos à cirurgia de implante coclear bilateral sequencial é pouco conhecido. Contudo, a pesquisa dos potenciais evocados auditivos corticais pode auxiliar na compreensão de como ocorrem o desenvolvimento, a plasticidade e a função cortical destes pacientes. Os objetivos deste trabalho foram caracterizar longitudinalmente o complexo P1-N1-P2 dos potenciais evocados auditivos corticais em usuários de implante coclear bilateral sequencial que realizaram a ativação do primeiro implante coclear na infância e a ativação do segundo dispositivo na adolescência; e analisar sua correlação com a percepção auditiva da fala. A casuística foi composta por indivíduos atendidos no Centro de Pesquisas Audiológicas, Seção de Implante Coclear, do Hospital de Reabilitação de Anomalias Craniofaciais da Universidade de São Paulo, com perda auditiva pré-lingual e usuários de implante coclear bilateral. A pesquisa dos potenciais evocados auditivos corticais foi realizada com o estímulo de fala /da/, apresentado em campo livre em cinco momentos distintos: antes da cirurgia do segundo implante coclear, na ativação do segundo dispositivo e com três, seis e 12 meses após a ativação do segundo implante coclear. Os registros obtidos foram analisados pela pesquisadora e por um juiz experiente em eletrofisiologia a fim de verificar a concordância das análises. Houve concordância de 100% (Kappa=1) entre os juízes quanto à ocorrência dos componentes P1, N1 e P2, com coeficiente de correlação interclasse excelente para os valores de latência e amplitude. A resposta cortical obtida com o uso dos dois implantes cocleares ligados, aparentemente, reflete a melhor resposta cortical obtida, quanto à ocorrência e latência dos componentes, independente se registrada com o primeiro implante coclear ou com o segundo implante coclear ligado. Os componentes P1, N1 e P2 dos potenciais evocados auditivos corticais não são preditores dos resultados de percepção auditiva da fala tanto no silêncio quanto no ruído. / The redirection of central auditory structures in patients who underwent sequential bilateral cochlear implant surgery is little known. However, cortical auditory evoked potentials testing can aid in understanding how the development, the plasticity and cortical function of these patients, occur. This study aimed at characterizing, longitudinally, the P1-N1-P2 complex of cortical auditory evoked potentials in sequential bilateral cochlear implant users who had the first cochlear implant fitted in their childhood and the second device activated in their adolescence, and analyze its correlation with speech auditory perception. The sample consisted of individuals seen at the Audiological Research Center of the Craniofacial Anomalies Rehabilitation Hospital of the University of São Paulo, with pre-lingual hearing loss, users of bilateral cochlear implant. The cortical auditory evoked potentials research was performed with the /da/ speech stimulus, presented in free field, in five different times: before the second cochlear implant surgery, upon the fitting of the second device and three, six and 12 months following the activation of the second cochlear implant. The records obtained were analyzed by the researcher and by a judge experienced in electrophysiology, so as to verify the agreement of the analyses. A 100% agreement (kappa = 1) was seen between judges as to the occurrence of P1, N1 and P2, with an excellent inter-class correlation coefficient for the latency and amplitude values. The cortical response obtained with the use of the two cochlear implants, turned on, apparently reflects the best cortical response accomplished, as to the occurrence and latency of the components, regardless of being recorded with the first cochlear implant, or with the second one, turned on. The P1, N1 and P2 components of cortical auditory evoked potentials are not predictors of the results of auditory speech perception, both in silence and in noise.

Introdução: O potencial evocado auditivo de estado estável (PEAEE) é uma técnica promissora no diagnóstico precoce da surdez, tratando-se de um método objetivo, que estima o grau de sensibilidade em diferentes freqüências e oferece recursos diferenciais como: o emprego da avaliação dicótica e simultânea para diferentes freqüências, tornando o teste mais rápido, além da detecção automática da resposta garantindo a confiabilidade dos resultados. Objetivo: obter limiares para o PEAEE, em lactentes nascidos a termo e pré-termo, com audição normal, a fim de investigar o processo de maturação das respostas e verificar possíveis ajustes no protocolo, para aplicação clínica no diagnóstico precoce da surdez. Método: estudo coorte e prospectivo para análise dos limiares obtidos no PEAEE para 60 orelhas (30 para cada grupo) utilizando o programa Master®, com análise automática da resposta, pela aplicação do F-teste, com p-valor < 0,01, pesquisa de limiar em 5-5 dB, com estimulação monótica e simultânea para 500, 1000, 2000 e 4000 Hz. Resultados e discussão: Os limiares encontrados, em dB NPS foram mais elevados para o grupo Pré-termo sendo, em média, 49,11 (± 9,44), 26,38 (± 6,59), 26,74 (± 7,57) e 35,9 (± 8,23) e para o grupo Termo foram em média 44,30 (± 9,88), 27,8 (± 6,79), 26,77 (± 6,09) e 32,87 (± 6,12), para as freqüências de 500, 1000, 2000 e 4000 Hz, respectivamente. O protocolo sugerido foi viável e o tempo de coleta foi em média 1h e 20 min. O tempo de coleta pode ser reduzido para 40 minutos, visando a aplicação clínica, se utilizadas as condições de p-valor < 0,05 e pesquisa de limiar em 10-10 dB, já que a diferença entre os limiares foi de apenas 2 dB, quando comparados aos resultados obtidos pelo protocolo sugerido. Os critérios p-valor < 0,01 e pesquisa de limiar de 5-5 dB podem ser estratégias para confirmação da resposta, pois apesar da detecção automática ser um diferencial desta metodologia esta não eximiu a interpretação do examinador para análise final dos resultados. Conclusão: Os limiares para o PEAEE, em lactentes com audição normal demonstram o amadurecimento das respostas entre 35-39 semanas de idade. Os resultados encontrados foram mais elevados do que o esperado, para respostas eletrofisiológicas, especialmente para as freqüências de 500 e 4000 Hz e, portanto, sua aplicação deve ser criteriosa para identificação de lactentes com audição normal. / Introduction: Auditory steady-state evoked response (ASSR) is a promising technique to early diagnosis of hearing loss, as an objective method to estimate hearing sensibility in different frequencies. This technique offers some particular features: the use of dichotic and simultaneous frequency stimulation, allowing a short-duration assessment in addition to the automatic response detection providing a reliable outcome. Objective: to obtain ASSR thresholds, for preterm and term young-infants, with normal hearing, to investigate the maturational process of response and to verify how the protocol could be adjusted, for clinical application for early detection of hearing loss. Method: a cohort and prospective analysis of ASSR thresholds obtained to 60 ears (30 per group) by Master® program using monotic and simultaneous frequency stimulation for 500, 1000, 2000 and 4000 Hz, with automatic response detection, by the F-test, at p-value <0.01 and 5 dB-step threshold seek. Results and Discussion: the thresholds for Preterm group were higher than Term and the mean values, in dB SPL, were 49.11 (± 9.44), 26.38 (± 6.59), 26.74 (± 7.57) and 35.9 (± 8. 3) for Preterm group and 44.30 (± 9.88), 27.8 (± 6.79), 26.77 (± 6.09) and 32.87 (± 6.12), for Term group at 500, 1000, 2000 and 4000 Hz, respectively. The adopted protocol was feasible and the average time collection was 1h 20 min. The time collection can be reduced to 40 min, for clinical application, considering the response detection at p-value < 0.05 and 10 dB-step threshold seek, as the difference on thresholds were only 2 dB, when compared to the suggested protocol. The p-value < 0.01 and 5-dB step threshold seek can be a strategy to confirm the presence of response, besides the automatic detection, which does not exclude the examiner interpretation for final outcomes. Conclusion: The ASSR thresholds in young-infants, with normal hearing, demonstrate a maturational effect from 35 to 39 weeks of age. The ASSR results were elevated, considering an electrophysiological response, especially for 500 and 4000 Hz, and therefore it has to be applied carefully to identify normal hearing neonates.

Introdução: Os limiares do potencial evocado auditivo de estado estável (PEAEE) em neonatos e lactentes até o sexto mês de vida auxiliam a predizer os limiares psicoacústicos em um período que os mesmos não respondem precisamente a testes comportamentais. Objetivo: Caracterizar os limiares dos PEAEE relacionadas à idade em neonatos e lactentes a termo, a fim de averiguar a influência do processo maturacional na resposta elétrica do sistema auditivo. Metodologia: Estudo transversal, no qual foram avaliados 60 neonatos e lactentes divididos em três grupos: GI - zero a um mês e 29 dias, n=20; GII - dois a três meses e 29 dias, n=20; GIII - quatro a seis meses, n=20. O PEAEE foi pesquisado utilizando-se tons puros nas frequências portadoras de 0,5, 1, 2 e 4 kHz modulados 100% em amplitude e 20% em frequência, com modulação de 91,406, 93,750, 96,094 e 98,437 Hz, respectivamente, na intensidade variando de 60 a 0 dB NA, apresentados por meio de fones de inserção ER-3A, de forma simultânea e monoaural; eletrodos em Fz (ativo), Oz (referência) e Fpz (terra); ganho de 50000, filtro passa banda 1-300 Hz, 6 dB/oitava. O Real-Ear to Dial Difference (REDD) foi mensurado no conduto auditivo externo (CAE) usando-se um microfone sonda de silicone do equipamento Hearing aid Analyzer FONIX FP 35 (Frye Electronics) . Resultados: Houve diferença estatisticamente significante entre os grupos para os valores de REDD apenas na frequência de 4 kHz, o que não foi observado para os limiares dos PEAEE. Com relação à variável frequência portadora, observou-se diferença significante tanto para o REDD quanto para o PEAEE, com associação entre os mesmos, ou seja, os limiares dos PEAEE decresceram para o intervalo de frequência de 0,5 a 2,5 kHz e cresceram quando a frequência aumentou para 4 kHz ocorrendo o inverso no REDD. Conclusão: A caracterização dos limiares dos PEAEE nos primeiros seis meses de vida demonstrou que um mesmo limiar pode ser utilizado como referência de normalidade para esta faixa etária, com valores distintos para as diferentes frequências portadoras. A influência da amplificação do CAE nos limiares dos PEAEE deve ser considerada, havendo a possibilidade de a mesma mascarar a influência do processo maturacional na resposta elétrica do sistema auditivo. / Introduction: The thresholds of the auditory steady-state evoked potentials (ASSEP) in newborns and infants up to the sixth month of life help to predict the psychoacoustic thresholds in a period in which they do not precisely respond to behavioral tests. Objective: To characterize the thresholds of ASSEP related to age in term newborns and infants, so as to verify the influence of the maturational process on the hearing systems electric response. Methodology: A cross-sectional study which assessed 60 newborns and infants divided into three groups: GI - zero to a month and 29 days, n=20; GII two to three months and 29 days, n=20; GIII four to six months, n=20. The ASSEP research used pure tones in the carrier frequencies of 0,5, 1, 2 and 4 kHz modulated 100% in amplitude and 20% in frequency, with a modulation of 91,406, 93,750, 96,094 and 98,437 Hz, respectively, in the intensity, ranging from 60 to 0 dB NA, presented through ER-3A insertion phones, simultaneous and mono-aurally; electrodes in Fz (active), Oz (reference) and Fpz (ground); gain of 50000, pass band filter 1-300 Hz, 6 dB/octave. The Real-Ear to Dial Difference (REDD) was measured in the external auditory canal (EAC) by using a silicone probe microphone of the Hearing aid Analyzer FONIX FP 35 equipment (Frye Electronics) . Results: A statistically significant difference was seen among the groups for REDD values only in the frequency of 4 kHz, but not observed for ASSEP thresholds. In relation to the carrier frequency variable, a significant difference was observed for both REDD and ASSEP, with association among them, that is, the ASSEP thresholds decreased for the frequency interval 0,5 to 2,5 kHz and increased when the frequency was 4 kHz, the opposite occurring for REDD. Conclusion: The characterization of ASSEP thresholds in the first six months of life showed that the same threshold can be used as a normality reference for this age range, with distinct values for the different carrier frequencies. The influence of EAC amplification in the ASSEP thresholds should be taken into account, since it may mask the influence of the maturational process on the auditory systems electric response.

O chumbo (Pb) é um metal pesado que pode ocasionar alterações nos sistemas nervoso central (SNC) e auditivo. Faltam estudos que demonstrem tais alterações clínicas, em conjunto com as alterações bioquímicas e morfológicas em cérebro de ratos expostos ao Pb. Tem sido relatado que o ferro (Fe) tem um efeito protetor na toxicidade cerebral causada pelo Pb. O objetivo deste estudo foi avaliar a atividade elétrica cerebral, analisar a concentração de Pb no sangue e tecido cerebral, e observar o aspecto morfológico do cérebro de ratos intoxicados por Pb, submetidos à suplementação com Fe ou não. Foi realizado um projeto piloto utilizando 20 ratos machos recém-desmamados (Rattus norvegicus, variedade Wistar), que foram divididos em 5 grupos, sendo um controle e 4 experimentais (n=4/grupo). Nos grupos experimentais, os animais receberam por 6 semanas acetato de chumbo em água de beber nas concentrações de 100 mg/L e 400 mg/L de Pb, e em dois destes grupos houve administração simultânea de 20 mg/Kg de FeSO4 a cada 2 dias, por gavagem gástrica, e no outro não. O grupo controle recebeu, água deionizada. Após estabelecida a relação entre o Pb administrado e a dosagem deste no sangue (10 &#x3BC;gPb/dL e 30 &#x3BC;gPb/dL para as dosagens 100 e 400 mg/L de Pb, respectivamente), o experimento foi realizado com 30 ratos recém-desmamados divididos em 6 grupos (n=5/grupo). Os cinco primeiros foram idênticos aos empregados no estudo piloto, incluindo um grupo no qual os animais receberam água deionizada e 20 mg/Kg FeSO4 por gavagem gástrica a cada 2 dias, por 6 semanas. Após o período experimental, foi realizado o Potencial Evocado Auditivo Cortical (PEAC) com a análise da latência dos componentes P1, N1 e P2. Após a eutanásia, o cérebro dos animais foi removido, submetido ao processamento histológico (hematoxilina e eosina) e analisado ao microscópio óptico. Os dados foram analisados por ANOVA/Tukey, Kruskal-Wallis/Dunn e regressão linear (p<0,05). Foi observada uma dose-resposta em relação à concentração de Pb no sangue e no cérebro. A administração de FeSO4 reduziu os níveis de Pb no sangue e no cérebro, e embora a diferença só tenha sido significativa para o sangue (grupo que recebeu 100 mg/L de Pb), houve correlação significativa entre os níveis de Pb no sangue e cérebro (r2 = 0,94; p<0,0001). A latência média dos componentes P1, N1 e P2 do PEAC foi maior para os animais do grupo 400 mg/L Pb + 20 mg/Kg FeSO4. Não foram observadas alterações morfológicas significativas no tecido cerebral dos animais dos diferentes grupos, com exceção de alguns espaços pericelulares nos animais do grupo 400 mg/L Pb + 20 mg/Kg FeSO4. Conclui-se que a ingestão de Pb sozinho não foi capaz de causar aumentou nas latências dos componentes P1, N1 e P2 do PEAC e alteração morfológica no tecido cerebral, com exceção da maior dose de Pb utilizada (400 mg/L), associada ao uso do Fe (20 mg FeSO4). Além disso, a suplementação com o Fe foi capaz de diminuir os níveis do metal no sangue e no cérebro. / Lead (Pb) is a heavy metal that may cause alterations in the central nervous system (CNS) and auditory system. There is lack of studies demonstrating these clinical alterations, combined to the biochemical and morphological alterations in the brain of rats exposed to Pb. It has been reported that iron (Fe) has a protective effect on the brain toxicity caused by Pb. This study evaluated the electrical brain activity, analyzed the Pb concentration in blood and brain tissue, and observed the morphological aspect of the brain in rats intoxicated by Pb, submitted or not to Fe supplementation. A pilot study was conducted on 20 recently weaned male rats (Rattus norvegicus, Wistar type) divided in 5 groups, being one control and 4 experimental (n=4/group). In the experimental groups, the animals received lead acetate in drinking water for 6 weeks at concentrations of 100 mg/L and 400 mg/L of Pb, and in two of these groups there was simultaneous administration of 20 mg/Kg of FeSO4 at every 2 days, by gastric gavage. The control group received deionized water. After establishing the relationship between the administered Pb and its concentration in blood (10 &#x3BC;gPb/dL and 30 &#x3BC;gPb/dL for concentrations of 100 and 400 mg/L of Pb, respectively), the study was conducted on 30 recently weaned rats divided in 6 groups (n=5/group). The five first groups were identical to those used in the pilot study, including one group in which the animals received deionized water and 20 mg/Kg FeSO4 by gastric gavage at every 2 days, for 6 weeks. After the study period, the Cortical Auditory Evoked Potential (CAEC) was applied for analysis of latency of the components P1, N1 and P2. The animals were killed, their brains were removed and submitted to histological processing (hematoxylin and eosin) for light microscopy analysis. Data were analyzed by the ANOVA/Tukey, Kruskal-Wallis/Dunn and linear regression tests (p<0.05). A dose- response relationship was observed in the Pb concentration in blood and brain. The administration of FeSO4 reduced the Pb levels in blood and brain, and even though the difference was only significant for blood (group receiving 100 mg/L of Pb), there was significant correlation between the Pb levels in blood and brain ((r2 = 0.94; p<0.0001). The mean latency of components P1, N1 and P2 of the CAEC was higher in animals in the group 400 mg/L Pb + 20 mg/Kg FeSO4. No significant morphological alterations were observed in the brain tissue of animals in the different groups, except for some pericellular spaces in animals in the group 400 mg/L Pb + 20 mg/Kg FeSO4. It was concluded that Pb ingestion individually was not able to increase the latencies of components P1, N1 and P2 of the CAEC and morphological alterations in the brain tissue, except for the highest Pb dose used (400 mg/L), associated to the use of Fe (20 mg FeSO4). Additionally, the Fe supplementation was able to reduce the levels of the metal in the blood and brain.

Objetivo: Avaliar e comparar os achados dos Potenciais Evocados Auditivos de Tronco Encefálico em indivíduos com holoprosencefalia (HPE) e holoprosencefalia-like (HPE-like). Modelo: Análise prospectiva comparando os achados dos PEATE entre três grupos: indivíduos com HPE clássica (GH), indivíduos com HPE-like (GHL) e grupo controle (GC), a um nível de significância de 5%. Local de Execução: Setor de Genética, HRAC-USP. Participantes: 57 pacientes, com idades entre 1 ano e 6 meses e 22 anos, sendo 13 com HPE clássica, 22 com HPE-like, e um grupo controle de 22 indivíduos normais. Variáveis: Latências absolutas das ondas I, III e V; latências interpicos I-V, III-V e I-III e diferença interaural da onda V do PEATE, em milissegundos, para cada orelha. Resultados: Os valores médios em milissegundos das latências absolutas e interpicos nas orelhas direita e esquerda respectivamente foram os seguintes. ara a onda I: 2,21 e 2,19 (GH); 1,99 e 2,01 (GHL); 1,92 e 1,91 (GC). Para a onda III: 4,35 e 4,52 (GH); 4,04 e 4,04 (GHL); 3,97 e 3,94 (GC). Para a onda V: 6,47 e 6,51 (GH); 5,95 e 5,94 (GHL); 5,90 e 5,90 (GC). Para o interpicos I-V: 4,20 e 4,24 (GH); 3,94 e 3,92 (GHL); 3,97 e 3,97 (GC). Para o interpicos III-V: 2,27 e 2,07 (GH); 1,91 e 1,90 (GHL); 1,92 e 1,95 (GC). Para o interpicos I-III: 2,14 e 2,33 (GH); 1,03 e 2,01 (GHL); 2,04 e 2,01 (GC). Os valores de diferença interaural da onda V foram: 0,13 (GH); 0,06 (GHL) e 0,03 (GC). Conclusões: Os dados sugerem que grande parte dos indivíduos com HPE clássica apresentam alterações de PEATE compatíveis com o grau de comprometimento neurológico, enquanto aqueles com HPE-like apresentam poucas alterações, sendo estas justificadas pelas patologias de orelha média decorrentes da fissura de palato. / Objective: To evaluate and compare Auditory Brainstem Response (ABR) findings in patients with holoprosencephaly (HPE) and the “HPE-like" phenotype. Model: A prospective analysis comparing ABR results among three different groups: patients with classic HPE (GH), patients with HPE-like (GHL) and control group (GC), at a 5% significance level. Setting: Genetics Department, HRAC-USP. Participants: 57 patients, aged from 18 months to 22 years. Thirteen of them had classic HPE, 22 had HPE-like, and 22 were audiologically normal individuals, who joined the GC. Variables: Waves I, III and V absolute latencies; interpeak intervals I-V, III-V and I-III and wave V interear difference of ABR, in milisseconds, considering both right and left ears. Results: Mean values, in milisseconds, of absolute latencies and interpeaks recorded from right and left ears, respectivelly, were: Wave I: 2,21 and 2,19 (GH); 1,99 and 2,01 (GHL); 1,92 and 1,91 (GC). Wave III: 4,35 and 4,52 (GH); 4,04 and 4,04 (GHL); 3,97 and 3,94 (GC). Wave V: 6,47 and 6,51 (GH); 5,95 and 5,94 (GHL); 5,90 and 5,90 (GC). Interpeak I-V: 4,20 and 4,24 (GH); 3,94 and 3,92 (GHL); 3,97 and 3,97 (GC). Interpeak III-V: 2,27 and 2,07 (GH); 1,91 and 1,90 (GHL); 1,92 and 1,95 (GC). Interpeak I-III: 2,14 and 2,33 (GH); 1,03 and 2,01 (GHL); 2,04 and 2,01 (GC). Wave V interear difference were: 0,13 (GH); 0,06 (GHL) and 0,03 (GC). Conclusions: Results suggest that most patients with classic HPE have abnormalities detected by ABR testing, which are related to the severity of neurologic impairment. Otherwise, those with the HPE-like phenotype have few alterations, most likely resulting from middle ear pathologies that occur in presence of cleft palate.

When a baby is born deaf, a cochlear implant is often recommended as a medical habilitation tool to the parents. A cochlear implant is designed to bypass a damaged cochlea and stimulates auditory nerve directly, from where signals are sent all the way to the auditory cortex where sounds are perceived. We expect that a deaf child can detect and discriminate speech sounds with this device. With continuous auditory experiences, we hope that the auditory cortex of the deaf child can be developed as children with normal hearing do. Can a cochlear implant facilitate the development of the auditory brain? This study attempts to answer this question, exploring developmental effects on evoked potentials measured at the cortical level. Early-implanted, pre-lingually deafened cochlear implant users showed similar developmental patterns of cortical auditory evoked potentials to those of normal hearing listeners. However, the responses, related to sound discrimination, were affected by noise more in cochlear implant users. This may be related to perceptual abilities of cochlear implant users in harder listening conditions. The findings indicate that cortical auditory evoked potentials, related to both detection and discrimination, can be used to document the long developmental trajectory of the central auditory system in both normal hearing listeners and cochlear implant users. This study suggests that these responses can be used as a tool for estimating behavioral performance in cochlear implant users.

Archery can be described as a static sport requiring strength and endurance of the upper body, in particular the shoulder girdle (Mann, 1984 / Mann &amp / Littke, 1989). To get a good record in an archery competition, one requires well-balanced and highly reproducible movements during the shooting (Nishizono, 1987). The bowstring is released when audible impetus is received from a device called &ldquo / clicker&rdquo / . As the fall of the clicker is an acoustic stimulus, it may evoke a sequence of potentials that can be recorded from the scalp of an archer. Auditory Evoked Potentials (AEPs) occur at different latencies and with various relations to the auditory stimuli. Therefore, the present study aims at investigating the Long-latency Auditory Evoked Potentials in Recurve Archery. Research questions can be stated briefly as follows: (1) What kind of Brain Potentials are Evoked by the Event (Fall of Clicker) during Archery Shooting? (2) Is there any significant difference between the characteristics of the potentials measured in laboratory conditions and during archery shooting? (3) Is there any significant difference between the successful and unsuccessful shots in terms of Auditory Evoked Brain Potentials? (4) Does Archery Shooting session have any effect on Auditory Evoked Brain Potentials? The subjects of the present study were 10 non-archers (N=6 males / N=4 females) for control trials and 15 archers (N=9 males / N=6 females) for archery shooting experiments. All subjects reported normal hearing, had medical histories free of significant neurological problems, and were not taking medication known to affect brain activity. Six different control paradigms have been created. Archery shootings were performed from 18 m that is official competition distance with target face.AEBPs were recorded 200 ms before and 800 ms after the trigger (fall of the clicker) over the vertex during the shots of each subject. Paradigm 1 and 5 was conducted just before and after the archery shooting to test the effect of archery shooting on AEBPs. The hit-area is defined as the rectangle between (x1, y1), (x1, y2), (x2, y1), (x2, y2) and the miss-area is the outer part of the hit-area on the target face. The preliminary analysis has shown that fall of the clicker evokes long latency auditory brain potentials with the latency of 100 msec and 200 msec. These responses are called as N1-P2 components. The means and standard deviations of both N100 and P200 amplitudes were as follows: N100 = 27,73 &plusmn / 16,82, P200 = -21,89 &plusmn / 20,46. The latencies of given brain responses were also summarized as: N100 = 141,93 &plusmn / 41,46 / P200 = 211,8 &plusmn / 43,97. N1 amplitude was significantly different in archery shooting than that of control conditions (p&lt / 0.05) except for trial 3, N1 latency was significantly different than that of trial 2 &ndash / 5 (p&lt / 0.05). P2 amplitude is significantly different in archery shooting than that of trial 6 (p&lt / 0.05). However, there was no significant difference in terms of P2 latency between archery shooting and control conditions (p&gt / 0.05). There was no significant difference between successful and unsuccessful shots in terms of N1-P2 components (p&gt / 0.05). An archery shooting session did not create any difference between these components recorded before and after the shot (p&gt / 0.05). Having higher N1 amplitudes during archery shooting can be explained by the known multi-component structure of this wave. Different lobes and regions of the brain can be active during the time of the scalp-recorded N1 and simultaneous involvement of several of these areas may be contributing to the electrical field recorded at scalp in the archery shooting paradigm.

Typical depredation behavior by cetaceans involves stealing or damaging prey items already captured by recreational or commercial fishing gear. Depredation among cetaceans has been reported to be increasing in both severity and frequency globally. This behavior is of particular concern for small stocks of cetaceans since any interaction with fishing gear has the potential to injure or kill animals leading to unsustainable losses. In Florida, depredation became evident in 2006 when the number of bottlenose dolphin (Tursiops truncatus) strandings resulting from fishing gear ingestion or entanglement sharply increased. For the resident dolphin community in Sarasota Bay, modeling showed continued mortalities from recreational fishing gear interactions were not sustainable. The major goals of this study were to 1.) characterize depredation and recreational angler interactions involving dolphins in Sarasota Bay, 2.) reduce dolphin-angler interactions through outreach, 3.) examine a case study to investigate the link between dolphin hearing loss and angler interaction behavior, 4.) test the effectiveness of passive acoustics in monitoring dolphin depredation at a fishing pier. Findings from this study provided a better understanding of depredation and angler interactions. Results indicated that dolphin-angler interactions in Sarasota Bay are increasing in frequency and are affecting an increasing number of dolphins, specifically adult males. Some dolphins in Sarasota Bay appear to utilize depredation as a foraging method (not just an opportunistic behavior) and were significantly more likely to be within 50 m of an active fishing line. Depredation and angler interaction behavior appear to increase in times of prey depletion (such as during a red tide) and heightened angler fishing activity. Educational outreach using an informational card proved successful in a case study showing about a 30% reduction in dolphin provisioning rates. The case study of F201 offers preliminary evidence that hearing loss is linked to depredation behavior and death for wild dolphins. Also, by detecting echolocation clicks as a proxy for dolphin presence, passive acoustics showed potential as an inexpensive method for monitoring depredation in problematic areas. Conclusions from this study can be utilized by scientists and managers when assessing depredation rates for a cetacean community and implementing an action plan.