The purpose of this study was to determine the effects of task difficulty on the amplitude and latency of the P300 by altering the intensity of the oddball stimulus. A P300 was obtained on 22 adult subjects ranging in age from 21 to 34 years of age (mean = 24 years) with normal hearing. The "frequent stimulus" was a 1000 Hz or 4000 Hz tone burst, gated with a rise and fall time of 10 msec and 20 msec plateau, presented at 75 dBn HL The "oddball stimulus" was a tone burst of the same frequency (1000 Hz or 4000 Hz)presented at 77, 79, or 81 dBn HL. A four-channel recording was made with linked reference electrodes and the following montages:Cz-A1+A2, Pz-A1+A2, and Fz-A1+A2. The fourth channel was used to monitor "eye blink" activity. The investigation tested the null hypothesis that changing the intensity of the oddball stimuli would not result in a significant change in either the amplitude or latency of the P300. Analyses of Variance (ANOVA) indicate that P300 latency and amplitude did not differ significantly by run, stimulus frequency, intensity of the oddball, or montage. Thus the null hypothesis was supported.

Introdução: Entre as queixas mais comuns dentro dos consultórios de otorrinolaringologia e fonoaudiologia, o zumbido destaca-se como uma das que geram mais incômodo ao indivíduo. Existem várias modalidades para o tratamento do zumbido, com destaque para a terapia farmacêutica, fisioterapia, psicoterapia, cirurgia, e dentre as possibilidades de intervenção, vem crescendo o interesse no uso do laser de baixa intensidade. No entanto, apesar de existir na literatura internacional artigos sobre este assunto, há inúmeras divergências quanto ao protocolo de aplicação e a eficácia desse tratamento. Proposição: Verificar o efeito da fotobiomodulação em indivíduos com sintoma de zumbido crônico sem perda auditiva. Casuística e Métodos: O estudo foi desenvolvido no Centro Auditivo Ouvir Bauru, com a aprovação do Comitê de Ética em Pesquisa e aquiescência do paciente confirmada mediante a assinatura do Termo de Consentimento Livre e Esclarecido. Os pacientes que se enquadravam nos critérios de inclusão foram divididos aleatoriamente em Grupo 1: uso do laser de baixa intensidade e Grupo 2: uso do placebo. Foi realizado anamnese com os indivíduos antes da realização da bateria de testes e os dados coletados foram anotados no prontuário do mesmo. Após entrevista, iniciou-se a bateria de exames audiológicos que incluiu: audiometria tonal, audiometria de altas frequências, imitanciometria e acufenometria para descarte de perda auditiva, questionário Tinnitus Handicap Inventory para mensurar o nível de incomodo com o zumbido pré e pós tratamento e escala visual analógica para mensurar o nível de incômodo pré e pós aplicação do laser. O protocolo de fotobiomodulação incluiu 12 sessões de laser de baixa intensidade para o Grupo 1 e placebo para o Grupo 2, utilizando 4J na veia lingual no comprimento de onda vermelho, 4J na membrana timpânica direita e esquerda, no comprimento de onda vermelho e 9J na mastoide direita e esquerda, no comprimento de onda infra-vermelho. Resultados: a amostra foi composta por 20 pacientes, sendo oito do sexo feminino e 12 do sexo masculino com média de idade de 54 anos. Não houve diferença estatística em função do grupo de intervenção e do momento de avaliação para os desfechos audiometria de altas frequências e acufenometria. A desvantagem dos indivíduos com zumbido crônico reduziu significativamente após a intervenção, independentemente da intervenção. Pode-se averiguar que a insatisfação dos indivíduos com zumbido crônico diminuiu significativamente com diferença entre as sessões iniciais e finais, independentemente do grupo de intervenção, porém, o Grupo 1 apresentou redução significativamente maior que o Grupo 2, independentemente do momento de avaliação e do número da sessão. Conclusão: Conclui-se que indivíduos com zumbido crônico reduziram a desvantagem independentemente do grupo de intervenção, e o nível de insatisfação com o zumbido nas sessões iniciais em relação as finais independentemente do momento de avaliação e do grupo de intervenção. O grupo que recebeu a fotobiomodulação melhorou mais o nível de insatisfação com o zumbido, independentemente do momento de avaliação e do número da sessão. / Introduction: Among the most common complaints within otorhinolaryngology and audiology clinics, tinnitus stands out as one of the most uncomfortable for the subject. There are several modalities for the treatment of tinnitus, with emphasis on pharmaceutical therapy, physiotherapy, psychotherapy, surgery, and among the possibilities of intervention, there is growing significance in the use of low level laser. Nevertheless, despite many articles in the international literature about this theme, there are several disagreements regarding the protocol of application and the efficacy of this treatment. Proposition: To verify the effect of laser therapy in individuals with chronic tinnitus symptom without hearing loss. Methods: The study was developed at the Centro Auditivo Ouvir - Bauru, with the acceptance of the Research Ethics Committee and patient acquiescence confirmed by signing the Informed Consent Term. Patients who suited the inclusion criteria were randomly set to Group 1: treated with low level laser and Group 2: treated with placebo laser. Anamnesis was applied with the individuals before the battery of tests and the data collected were registered in the individuals folder. after the interview, the audiological exams started, which included: tonal audiometry, high frequency audiometry, immittanciometry and acufenometry for hearing loss disposal, Tinnitus Handicap Inventory to measure the level of discomfort with tinnitus pre and post treatment and visual analogue scale to measure the level of discomfort with tinnitus pre and post laser application. The Laser Therapy protocol included 12 laser therapy sessions for Group 1 and placebo laser for Group 2, using 4J in the lingual vein in the red wavelength, 4J in the right and left tympanic membrane, in the red wavelength, and 9J in the right and left mastoid, at the infra-red wavelength. Results: the sample consisted of 20 patients, eight females and 12 males with the average of 54 years-old. There was no statistical difference in function of the intervention group and the moment of evaluation for the high frequency audiometry and acuphenometry outcomes. The disadvantage of individuals with chronic tinnitus reduced significantly after the intervention, regardless of the intervention. It can be verified that the annoyance of individuals with chronic tinnitus decreased significantly with difference between the initial and final sessions, independently of the intervention group, but Group 1 presented a greater reduction than Group 2, independently of the moment of evaluation and the number of the session. Conclusion: It was concluded that individuals with chronic tinnitus reduced the disadvantage independently of the intervention group, and the level of discontentment with tinnitus in the initial sessions according to the final ones independently of the moment of evaluation and the intervention group. The group receiving laser therapy further improved the level of tinnitus dissatisfaction, regardless of timing and session number.

No description available.

Introduction: Due to our actual knowledge tinnitus in most cases results from abnormal neural activity elicited at any level of auditory pathways and is interpreted in auditory cortex as a perception of sound, which is not accompanied by any mechanic activity within the cochlea. Tinnitus patients usually present various degrees of cochlear dysfunction, which can be manifested as sensorineural hearing loss, loudness intolerance, a distinct decrease of the DPOAE amplitude, recruitment or abnormal efferent reduction of OAEs through contralateral acoustic stimulation. But 8-15% of tinnitus patients present normal audiometric profiles. In these patients the mechanism of tinnitus generation remains unclear. Aim of the study: The aim of the study was to assess DPOAE levels and EHF thresholds in tinnitus subjects with normal hearing and compare the data with those from a normally hearing control group without tinnitus, in order to evaluate if any detectable high frequency cochlear dysfunction might be responsible for the tinnitus generation. Material and methods: 175 tinnitus patients (group 1 – tinnitus in left ear - 47 patients, group 2 – tinnitus in right ear – 23 patients, group 3 – bilateral tinnitus – 105 patients) and 60 controls (group 4). Inclusion criteria: age up to 40, normal otoscopic examination, type A tympanometry, normal hearing (up to 20 dB) in PTA (250-8000 Hz), no loudness intolerance, constant tinnitus for at least 6 months of stable localization (site of tinnitus has not changed from the previous localization). In each patient high frequency audiometry (at 10, 12.5, 14 and 16 kHz) and DPOAE registration (L1=65 dB SPL, L2=55 dB SPL, f2/f1= 1.2, S/N≥3 dB) were performed. Then statistical analysis was applied for comparison between left and right ears in the same group and also across different group of patients. Results: statistically significant differences were observed mainly in unilateral tinnitus group. These differences were more evident in audiometric data than DPOAE data. Leftsided tinnitus was twice more frequent than right-sided tinnitus. Few statistically significant differences were found between bilateral tinnitus group and controls. Conclusions: Unilateral tinnitus in normally hearing individuals may be caused by the damage of the basal region of the cochlea. There is greater incidence of high frequency hearing loss (above 8 kHz) in the ear with tinnitus in comparison to control group. In unilateral tinnitus group, the organ of Corti at the site of tinnitus is more seriously damaged than in the opposite ear. The asymmetry of cochlear damage may be crucial for tinnitus lateralization. Bilateral tinnitus, more frequently than unilateral one, can result from other pathologies, not connected with the organ of Corti.

Background: A previous experiment with 70 interrupted monosyllabic words demonstrated that recognition performance was influenced by the location of an interruption pattern (Wilson, 2014). The interruption paradigm (10 interruptions/sec, 50% duty cycle periodic interruption) was referenced to word onset. The words were interrupted such that alternate 50-msec segments were parsed to separate files. In the 0-msec condition the first on-segment coincided with the word onset, whereas in the 50-msec condition the first on-segment occurred 50 msec after word onset. The 0- and 50-msec conditions were complementary halves. Recognition performance by young listeners was 19% better on the 0-msec condition (86%) than on the 50-msec condition (68%); there were a minority number of words on which the results were just the opposite. A second study using the same interruption paradigm but 300 different words reported similar relations, with 63% correct recognition on the 0-msec condition and 48% on the 50-msec condition (Wilson and Irish, 2015). Both studies suggest the importance that the first 50 msec of the target word has on intelligibility. Purpose: To define in detail the effects that interruption patterns have on word recognition as the interruption pattern was incremented with reference to word onset from 0 to 90 msec in 10-msec steps. Research Design: A repeated-measures design with ten interruption patterns (onset conditions). Study Sample: Twenty-four young listeners (19-29 yr) with normal hearing for pure tones participated in this study. Data Collection and Analyses: Seventy consonant-nucleus-consonant words formed the corpus of materials with 25 additional words used for practice. For each participant, the 700 stimuli (70 words by ten onset conditions) were interrupted (10 interruptions/sec; 50% duty cycle), randomized, and recorded on compact disc in 28, 25-word tracks. Results: The overall mean recognition performance was 80.4% with mean performances for the ten conditions ranging from 73.0% (50-msec condition) to 87.7% (90-msec condition). The mean recognition performances changed systematically, decreasing from the 0-msec condition to the 50-msec condition and then increasing to the 90-msec condition, which formed a U-shaped function of the means. Of the 45 mean paired comparisons (post hoc t-tests with Bonferroni corrections), there were 17 significant differences at the p ≤ 0.001 level, increasing to 31 significant differences when the significance level was increased to the p ≤ 0.01 level. Visual inspection of the 70-word performance functions revealed that 32 words had flat functions, 34 words had U-shaped functions, two functions were rising, one was an inverted V-shape, and one was irregular. Conclusions: First, some words (utterances of those words) were immune to any differential effects of the ten interruption patterns. These words with flat performance functions constituted 46% of the word corpus. Second, 49% of the words exhibited U-shaped performance functions that were always systematic, going from maximum to minimum and back to maximum. These words were thought to be more dependent on the initial consonant to attain maximum performance. The conclusion is that some words are not affected by the location of the interruption pattern (those with flat functions) whereas other words are substantially affected (those with U-shaped functions).

Background: Two previous experiments from our laboratory with 70 interrupted monosyllabic words demonstrated that recognition performance was influenced by the temporal location of the interruption pattern. The interruption pattern (10 interruptions/sec, 50% duty cycle) was always the same and referenced word onset; the only difference between the patterns was the temporal location of the onand off-segments of the interruption cycle. In the first study, both young and older listeners obtained better recognition performances when the initial on-segment coincided with word onset than when the initial on-segment was delayed by 50 msec. The second experiment with 24 young listeners detailed recognition performance as the interruption pattern was incremented in 10-msec steps through the 0-To 90-msec onset range. Across the onset conditions, 95% of the functions were either flat or U-shaped. Purpose: To define the effects that interruption pattern locations had on word recognition by older listeners with sensorineural hearing loss as the interruption pattern incremented, re: Word onset, from 0 to 90 msec in 10-msec steps. Research Design: A repeated-measures design with ten interruption patterns (onset conditions) and one uninterruption condition. Study Sample: Twenty-four older males (mean = 69.6 yr) with sensorineural hearing loss participated in two 1-hour sessions. The three-frequency pure-Tone average was 24.0 dB HL and word recognition was $80% correct. Data Collection and Analyses: Seventy consonant-vowel nucleus-consonant words formed the corpus of materials with 25 additional words used for practice. For each participant, the 700 interrupted stimuli (70 words by 10 onset conditions), the 70 words uninterrupted, and two practice lists each were randomized and recorded on compact disc in 33 tracks of 25 words each. Results: The data were analyzed at the participant and word levels and compared to the results obtained earlier on 24 young listeners with normal hearing. The mean recognition performance on the 70 words uninterrupted was 91.0% with an overallmean performance on the ten interruption conditions of 63.2% (range: 57.9-69.3%), compared to 80.4% (range: 73.0-87.7%) obtained earlier on the young adults. The best performances were at the extremes of the onset conditions. Standard deviations ranged from 22.1% to 28.1% (24 participants) and from 9.2% to 12.8% (70 words). An arithmetic algorithm categorized the shapes of the psychometric functions across the ten onset conditions.With the older participants in the current study, 40% of the functions were flat, 41.4% were U-shaped, and 18.6% were inverted U-shaped, which compared favorably to the function shapes by the young listeners in the earlier study of 50.0%, 41.4%, and 8.6%, respectively. There were two words on which the older listeners had 40% better performances. Conclusion: Collectively, the data are orderly, but at the individual word or participant level, the data are somewhat volatile, which may reflect auditory processing differences between the participant groups. The diversity of recognition performances by the older listeners on the ten interruption conditions with each of the 70 words supports the notion that the term hearing loss is inclusive of processes well beyond the filtering produced by end-organ sensitivity deficits.

Some tinnitus patients have normal hearing on the conventional audiogram. It has been suggested that the presence of a limited area of damaged outer hair cells (OHCs) with intact inner hair cells, which is not detected on the audiogram, results in unbalanced neural activity between Type I and Type II fibers leading to tinnitus. Distortion product otoacoustic emissions (DPOAEs) provided ambiguous data of OHC function in normal-hearing tinnitus patients when compared to non-tinnitus controls. It is known that hearing loss in the extended high frequency (EHF) region may decrease DPOAEs evoked at lower frequencies. Results of EHF audiometry in tinnitus patients are limited. The aim of the study was to evaluate DPOAEs and EHF thresholds in normal-hearing patients reporting unilateral tinnitus in left ear. Thus, each subject acted as their own control. Data were obtained for 25 subjects with bilateral hearing thresholds 3dB. Median audiometric data showed that thresholds in the left ears were significantly higher than those in the right ears at all four EHFs. Mean DPOAE levels of the left ears were lower than those of the right ears in the frequency range above 1 kHz. Additionally, a paired-comparison test of DPOAE levels of each patient’s right and left ear revealed significant differences at 6, and 8 kHz. The results indicate that: 1. OHC impairment in the most basal region reduces contribution to more apically generated DPOAEs; 2. OHC impairment in a limited area, which may be revealed by DPOAEs but not by conventional audiometry, can contribute to tinnitus generation; and 3. patients with unilateral tinnitus and normal hearing on the conventional audiogram are likely to demonstrate hearing loss in the EHF region.

Background: Hearing loss and age interfere with the auditory system's ability to process temporal changes in the acoustic signal. A key unresolved question is whether high-frequency sensorineural hearing loss (HFSNHL) affects temporal processing in the low-frequency region where hearing loss is minimal or nonexistent. A second unresolved question is whether changes in hearing occur in middle-aged subjects in the absence of HFSNHL. Purpose: The purpose of this study was twofold: (1) to examine the influence of HFSNHL and aging on the auditory temporal processing abilities of low-frequency auditory channels with normal hearing sensitivity and (2) to examine the relations among gap detection measures, self-assessment reports of understanding speech, and functional measures of speech perception in middle-aged individuals with and without HFSNHL. Research Design: The subject groups were matched for either age (middle age) or pure-tone sensitivity (with or without hearing loss) to study the effects of age and HFSNHL on behavioral and functional measures of temporal processing and word recognition performance. These effects were analyzed by individual repeated-measures analyses of variance. Post hoc analyses were performed for each significant main effect and interaction. The relationships among the measures were analyzed with Pearson correlations. Study Sample: Eleven normal-hearing young adults (YNH), eight normal-hearing middle-aged adults (MANH), and nine middle-aged adults with HFSNHL were recruited for this study. Normal hearing sensitivity was defined as pure-tone thresholds ≤25 dB HL for octave frequencies from 250 to 8000 Hz. HFSNHL was defined as pure-tone thresholds ≤25 dB HL from 250 to 2000 Hz and ≥35 dB HL from 3000 to 8000 Hz. Data Collection and Analysis: Gap detection thresholds (GDTs) were measured under within-channel and between-channel conditions with the stimulus spectrum limited to regions of normal hearing sensitivity for the HFSNHL group (i.e., <2000 >Hz). Self-perceived hearing problems were measured by a questionnaire (Abbreviated Profile of Hearing Aid Benefit), and word recognition performance was assessed under four conditions: quiet and babble, with and without low-pass filtering (cutoff frequency = 2000 Hz). Results: The effects of HFSNHL and age were found for gap detection, self-perceived hearing problems, and word recognition in noise. The presence of HFSNHL significantly increased GDTs for stimuli presented in regions of normal pure-tone sensitivity. In addition, middle-aged subjects with normal hearing sensitivity reported significantly more problems hearing in background noise than the young normal-hearing subjects. Significant relationships between self-report measures of hearing ability in background noise and word recognition in babble were found. Conclusions: The conclusions from the present study are twofold: (1) HFSNHL may have an off-channel impact on auditory temporal processing, and (2) presenescent changes in the auditory system of MANH subjects increased self-perceived problems hearing in background noise and decreased functional performance in background noise compared with YNH subjects.

No description available.

Abstract is available through the Journal of Hearing Science.