Central Auditory Changes Associated with Age-related Hearing Loss.

Objective. This study aimed to investigate age-related changes in cortical auditory evoked potentials (CAEPs) while considering three crucial factors: aging, high-frequency hearing loss and sensation level of the CAEP stimulus. Method. The electrophysiological and audiometric data of 71 elderly participants were analyzed using multiple regression analysis to investigate the association of CAEPs with the factors of aging, high-frequency hearing loss and sensation level of the CAEP test stimulus. Results. Aging was significantly associated with prolonged N1 and P2 latencies and reduced P2 amplitude. Elevated thresholds related to the sensation level of the CAEP stimulus were significantly associated with increased N1 and P2 amplitudes and decreased N1 latency. A significant relationship was detected between high-frequency hearing thresholds and the shortening of P2 latencies and the reduction of P2 amplitudes. Conclusion. The results of this study highlight the complex interplay of aging, high-frequency hearing loss and the sensation level of the CAEP stimulus on CAEP components in elderly people. These factors should be considered in future research using CAEPs to enhance overall understanding of auditory processing in the aging population.

The effect of sensorineural hearing loss on central auditory processing of signals in noise in older adults.

OBJECTIVES: The study aimed to explore the effect of sensorineural hearing loss on the central auditory processing of signals in noise using cortical auditory evoked potentials (CAEPs) in a cohort of older adults. DESIGN: Three groups of individuals participated in the study. Each group included 33 older adults with normal hearing, those with mild hearing loss and those with moderate hearing loss. N1-P2 peaks of CAEPs by speech stimuli in silent conditions and with varying sound pressure levels of background noise were recorded. CAEP latencies, amplitudes and relative changes in CAEP amplitudes as a function of decreasing signal-to-noise ratios (SNR) in three groups were analyzed using the mixed analysis of variance method. RESULTS: There was a significant main effect of SNR on all CAEP components, as well as significant main effects of hearing status on N1 latencies, amplitudes and relative changes in N1 amplitudes. A significant interaction was found between hearing status and SNR for relative changes in N1 amplitudes. The normal hearing group differed from both the mild and moderate hearing loss groups in terms of relative changes in N1 amplitudes at SNR 10 dB. CONCLUSION: The results showed decreased amplitudes and increased latencies for N1-P2 response as the SNR of CAEP stimuli was lowered. The degree of reduction in the N1 amplitudes of the older people with normal hearing resulting from the increase in the background noise level was greater than those in their sensorineural hearing-impaired counterparts, providing evidence for decreased central inhibition for individuals with age-related hearing loss.

Effect of Korean Red Ginseng on Noise-Induced Hearing Loss.

OBJECTIVE: Noise-induced hearing loss (NIHL) is one of the most important problems affecting both social and professional life of patients. There is no treatment method considered to be successful on the hearing loss that has become a permanent nature. Aim of this study is to evaluate protective effect of Korean Red Ginseng (KRG) against NIHL in an animal model. METHODS: Twenty-eight rats were separated into four groups [control saline (group I), control KRG (group II), saline + noise (group III), KRG + noise (group IV)]. Rats in the saline and KRG groups were fed via oral gavage with a dose of 200 mg/kg/day throughout for 10 days. Fourteen rats (group III and IV) were exposed to 4 kHz octave band noise at 120 dB SPL for 5 hours. Hearing levels of rats were evaluated by distortion product otoacoustic emissions (DPOAE) and auditory brainstem responses (ABR) at 4, 8, 12, 16 and 32 kHz frequencies prior to and on days 1, 7 and 10 after the noise exposure. Rats were sacrificed on 10th day, after the last audiological test. Cochlea and spiral ganglion tissues were evaluated by light microscopy. RESULTS: Audiological and histological results demonstrated that after noise the group IV showed better results than group III. In the noise exposed groups, the most prominent damage was seen at the 8 kHz frequency region than other regions. After the noise exposure, DPOAE responses were lost in 1st, 7th and 10th measurements in both group III and IV. Thus, we were not able to perform any statistical analyses for DPOAE results. CONCLUSION: Our findings suggest that KRG seems to be an efficient agent against NIHL. There is need for additional research to find out about the mechanisms of KRG's protective effect.

The effect of induction loop system use training on adults with hearing aids

Background/aim: The study aimed to investigate the effect of training on hearing aid users to benefit from induction loop systems. Materials and methods: A five-question scale was developed to evaluate whether individuals using hearing aids could use the induction loop system effectively. In the first step, validity-reliability studies were performed with 264 individuals using hearing aids. In the second step, 30 individuals using hearing aids were given verbal and hands-on training on the induction loop system. Before and after training with hearing aids (noiseless, noise, noise + induction system active) in three different environments, questions on the scale were asked twice in total from the beginning to the end of the study. Results: The significance of the differences between the values obtained as a result of the application of word lists in three different test settings was examined by repeating the measurements variance analysis. As a result of the post hoc analysis, P = 0.002 between test 3 (10.7, 1.53) and test 1 (11.7, 0.7) was calculated. There appears to be a statistically significant difference with the present situation (P < 0.01). The average scores of the scale between pre and posttraining applications as a preliminary and final test were analysed with a t-test. The final test average was statistically significantly greater than the preliminary test (P < 0.01). Conclusion: This study shows how important it is for hearing aid users to be informed and to receive the necessary training in order to gain the expected benefit from induction loop systems developed to improve speech intelligibility in noisy environments.

Changes in P1 latencies of children with normal hearing and those with cochlear implants

Background/aim: The aim of this study was to determine the age-related latency interval of P1 latencies of children with normal hearing, and to evaluate the P1 latency changes after surgery in children who underwent cochlear implantation. Materials and methods: We evaluated 60 children with normal hearing and 16 children with cochlear implants aged 0­6 years using cortical auditory evoked potentials. P1 latencies were measured only once in the children with normal hearing, and on the postoperative first day, and the first, third, and sixth postoperative months in the children with cochlear implants. Results: There was a statistically significant decrease in the P1 latencies as the age increased in children with normal hearing (P < 0.001). It was determined that when the external partof the cochlear implant was applied, the P1 latencies of children with cochlear implants were significantly longer than those of age-matched children with normal hearing (P < 0.001). This difference disappeared in 10 children with implants at the third and sixth months, but significant differences remained in 6 children. Conclusion: P1 latency could be used as an objective tool to evaluate the normal development of auditory pathways, and may be helpful in the effective programming of children undergoing cochlear implantation.

Comparison of Cortical Auditory Evoked Potential Findings in Presbycusis with Low and High Word Recognition Score.

BACKGROUND: Deteriorated speech understanding is a common complaint in elderly people, and behavioral tests are used for routine clinical assessment of this problem. Cortical auditory evoked potentials (CAEPs) are frequently used for assessing speech detection and discrimination abilities of the elderly, and give promise for differential diagnosis of speech understanding problems. PURPOSE: The aim of the study was to compare the P1, N1, and P2 CAEP latencies and amplitudes in presbycusis with low and high word recognition score (WRS). RESEARCH DESIGN: A cross-sectional study design was used forthe study. Two groups were formed from the patients with presbycusis based on their scores on the speech recognition test. STUDY SAMPLE: Fifty-seven elderly volunteers participated in the study. The first group composed of 27 participants with high WRS, the other group composed of 30 participants with low WRS. DATA COLLECTION AND ANALYSIS: The CAEP waves were recorded from these participants using speech signals. Latencies and amplitudes of P1 -N1-P2 waves of the two groups were compared with the f-test statistic. RESULTS: There were significant prolongation of P1 and N1 latencies in presbycusis with low WRS when compared with presbycusis with a relatively high word score (p < 0.05). CONCLUSION: According to the result of the research, P1 and N1 latencies of presbycusis with low WRS were longer than the participants with high WRS. Factors affecting peripheral auditory system, such as stimulus sensation level, might be responsible for P1 and N1 latency prolongation of the low WRS group.

Wide-Band Tympanometry Results during an Acute Episode of Ménière's Disease.

BACKGROUND: Wide-band tympanometry (WBT) was introduced as a beneficial diagnostic test for Ménière's disease (MD) almost 15 years ago. However, an acute episode of MD has not been evaluated by using WBT yet. OBJECTIVE: To investigate WBT findings in patients with MD during acute attacks. METHOD: Thirty definite MD patients with unilateral acute low-tone sensorineural hearing loss and aural fullness, and thirty age- and sex-matched control subjects were enrolled prospectively in a tertiary referral center. Ears were divided into three groups as follows: (1) affected ears of MD patients, (2) contralateral ears of MD patients, (3) control ears. Individuals underwent WBT. The resonance frequency (RF), mean absorbance value, mean low- and high-frequency absorbance values (LF-A and HF-A), and double peak width at 2 kHz of conductance tympanometry (2-kHz PW) were assessed. RESULTS: Seventy percent in group 1, 66.7% in group 2, and 78.3% in group 3 demonstrated double peaks at 2 kHz. The mean 2-kHz PW values were 157.52 ± 79.19, 177.40 ± 79.14, and 139.64 ± 87.501 daPa for groups 1, 2, and 3, respectively. There were no significant differences between groups with respect to 2-kHz PW, RF, absorbance, LF-A, and HF-A. CONCLUSION: This was the first study that evaluated the effects of acute Ménière attacks on WBT findings. An acute Ménière attack was found to have no significant effect on the 2-kHz PW and other variables measured using WBT.

The Effect of Tympanic Membrane Perforation Site, Size and Middle Ear Volume on Hearing Loss.

OBJECTIVE: The aim of this study was to analyze the location and the size of perforation in cases with tympanic membrane perforation, its relation to the manubrium mallei and middle ear volume, and to investigate how these are correlated with the severity and frequencies of conductive hearing loss. METHODS: This prospectively designed study included the patients who presented to the the Department of Otorhinolaryngology at the Dokuz Eylül University with hearing loss or tinnitus complaints in the period from June 2014 through June 2017 and were identified to have tympanic membrane perforation in their otoscopic examination. Patients who underwent myringoplasty and type 1 tympanoplasty and whose air-bone gap was found lower than 10 dB in the postoperative audiological examination were included in the study. Effects of the perforation size, the perforation site, and the relationship of the perforation with the manubrium, as well as the effects of the middle ear volume on the severity and frequency of conductive hearing loss were compared. RESULTS: The study included 44 ears of 38 patients (13 male and 25 female) of whom six had tympanic membrane perforation in both ears. Air conduction threshold and air-bone gap were significantly found higher if the perforation area was wide (p<0.05), the perforation involved both the anterior and the posterior quadrants (p<0.05), had contact with the manubrium mallei (p<0.05), and the middle ear volume reduced (p<0.05). CONCLUSION: Solely tympanic membrane perforation affects hearing function; nevertheless, hearing function are better in cases, which have perforations small in size, no contact with manubrium mallei and well pneumatized middle ears.

Early cochlear implantation: Verbal working memory, vocabulary, speech intelligibility and participant variables.

OBJECTIVES: The purpose of this study was to compare performance in the areas of verbal working memory (VWM), vocabulary skills, and speech intelligibility between children with cochlear implants (CIs) and children with typical development (TD). The correlations between participant variables and the scores of children with CIs in VWM and the measures of language were examined. Also, it was important to identify which variables predict VWM in children with CIs. METHODS: A total of 59 children participated in this study with the study group being comprised of 31 children who had received a CI and the control group being comprised of 28 children with TD. The assessment techniques utilized in this study were the backward digit span (BDS), non-word repetition, speech intelligibility, and vocabulary skills. RESULTS: The study results revealed significant differences in the non-word repetition, speech intelligibility, and vocabulary tasks. The results all favored the typically developing children while the findings for the BDS were equal for both groups. DISCUSSION: In children with CIs the results for VWM observed in this study are believed to be related to the modality of assessment presentation, prior vocabulary knowledge, and familiarity with the presented material. The results from this study also revealed that the variables which predicted VWM in children with CIs were speech perception, duration of CI use, and vocabulary knowledge.

Comparison of Cortical Auditory Evoked Potential Findings in Presbycusis with Low and High Word Recognition Score.

BACKGROUND: Deteriorated speech understanding is a common complaint in elderly people, and behavioral tests are used for routine clinical assessment of this problem. Cortical auditory evoked potentials (CAEPs) are frequently used for assessing speech detection and discrimination abilities of the elderly, and give promise for differential diagnosis of speech understanding problems. PURPOSE: The aim of the study was to compare the P1, N1, and P2 CAEP latencies and amplitudes in presbycusis with low and high word recognition score (WRS). RESEARCH DESIGN: A cross-sectional study design was used for the study. Two groups were formed from the patients with presbycusis based on their scores on the speech recognition test. STUDY SAMPLE: Fifty-seven elderly volunteers participated in the study. The first group composed of 27 participants with high WRS, the other group composed of 30 participants with low WRS. DATA COLLECTION AND ANALYSIS: The CAEP waves were recorded from these participants using speech signals. Latencies and amplitudes of P1-N1-P2 waves of the two groups were compared with the t-test statistic. RESULTS: There were significant prolongation of P1 and N1 latencies in presbycusis with low WRS when compared with presbycusis with a relatively high word score (p < 0.05). CONCLUSION: According to the result of the research, P1 and N1 latencies of presbycusis with low WRS were longer than the participants with high WRS. Factors affecting peripheral auditory system, such as stimulus sensation level, might be responsible for P1 and N1 latency prolongation of the low WRS group.

Sound energy absorbance characteristics of cartilage grafts used in type 1 tympanoplasty.

OBJECTIVE: The purpose of this prospective case-control study is to evaluate the sound energy absorbance characteristics of cartilage grafts in patients, who have undergone type 1 cartilage tympanoplasty. METHODS: Thirty-four operated ears of 32 patients and 70 ears of 35 control subjects were included. Differences of pure-tone audiometry thresholds and wideband ambient-pressure absorbance ratios with respect to the graft material, graft thickness, cartilage surface area ratio and elapsed time after surgery were analyzed. Receiver operating characteristics curve was generated to detect the absorbance level at which the reconstructed tympanic membrane behaves as 'near-normal tympanic membrane'. RESULTS: In the surgical group, wideband energy absorbance ratios at all 1/2-octave band frequencies were significantly worse than normal ears. Energy absorbance ratios at 2000 and 2828Hz frequencies were higher in patients with tragal cartilage grafts. Higher absorbance ratios at 250-750Hz range were obtained in patients with 400µm cartilage graft thickness, <50% cartilage surface area ratio and ≥5 years since surgery. A multivariate generalized linear model revealed common effects of the independent variables at 8000Hz. The receiver operating characteristics analysis generated a cut-off level of 63.20% of sound energy absorbance at 1400Hz with 83% sensitivity and 88% specificity. CONCLUSION: Even though no differences in hearing thresholds were observed; graft material, graft thickness, cartilage surface area ratio and elapsed time after surgery affected the course of sound energy absorbance after type 1 cartilage tympanoplasty as evidenced by wideband tympanometry.

The Reliability and Validity of "Dokuz Eylül University Meniere's Disease Disability Scale".

OBJECTIVE: Ménière's Disease (MD) is a chronic, non-life threatening inner ear disease, with attacks of disabling vertigo, progressive hearing loss, and tinnitus as the major symptoms. All three symptoms, separately or in combination, cause great distress and have a considerable impact on the quality of life of the patients. The aims of this study were to develop a disease-specific quality of life survey for patients with MD and to analyze the relationships between the audiovestibular findings and the survey. MATERIALS AND METHODS: Following Ear-Nose-Throat examination and audiovestibular tests, the Dokuz Eylül University Meniere's Disease Disability Scale (DEU-MDDS) and Turkish version of the Dizziness Handicap Inventory (DHI-T) were administered to 93 patients with definite MD. Reliability and validity analyses of the scale were performed. RESULTS: There were 45 (48.4%) male and 48 (51.6%) female patients and the mean age was 48.9±12.1 years. Cronbach's alpha was 0.92 and intraclass correlation coefficients of the DEU-MMDS were significant (p<0.001). Results of the Goodness of Fit Statistics showed that the expression levels of the items were high and the correlation coefficients of each item with the scale were sufficient. There was a statistically significant correlation between DHI-T scores and MDDS. DEU-MDDS was not related to the vestibular tests, age or gender (p>0.05). CONCLUSION: The MDDS is a valid and reliable scale as a disease-specific quality of life questionnaire for patients with MD.

Assessment of Synaptic Plasticity via Long-Term Potentiation in Young Mice on the Day after Acoustic Trauma: Implications for Tinnitus.

OBJECTIVE: This experimental study evaluated the pathophysiological association of long-term potentiation (LTP)-mediated synaptic plasticity in tinnitus in 30 BALB/c mice. MATERIALS AND METHODS: Baseline hearing levels and tinnitus perception were examined with startle reflex time and gap detection time measurements using an acoustic stimulus of a 6-kHz pure tone at 90 dB sound pressure level (SPL) on post-natal day 16. The acoustic trauma group was exposed to 6-kHz pure tone at 120 dB SPL on post-natal day 16. On post-natal day 17, the acoustic trauma group underwent re-measurements of hearing levels and tinnitus perception using an acoustic stimulus of 6-kHz pure tone at 100 dB SPL. Fifteen tinnitus-induced and fifteen control subjects were sacrificed on post-natal day 17, and LTP in the dorsal cochlear nuclei of each animal was examined. RESULTS: With respect to gap detection time, there were no statistically significant between-group differences; however, there was a statistically significant difference between the pre- and post-trauma period in the acoustic trauma group. Moreover, LTP was significantly higher in the acoustic trauma group than in the control group. CONCLUSION: The results suggest that LTP underlies tinnitus pathogenesis.

Effect of erythropoietin on acoustically traumatized rat cochlea: an immunohistochemical study.

OBJECTIVE: To investigate the audiological and histopathological effects of erythropoietin on acoustic overstimulation in rats. STUDY DESIGN: Twenty-two male Wistar albino rats were divided into 3 groups: sham group (n = 7), erythropoietin injection group (n = 8), and saline injection group (n = 7). Both erythropoietin and saline injection groups were exposed to white noise (100 decibel [dB] sound pressure level [SPL]) for 3 hours. Auditory brainstem responses were measured before, immediately after, and on the 7th day of noise exposure. All animals were sacrificed on the 7th day and temporal bones were collected. The serial sections of the cochleae were stained by caspase-3 and caspase-9 immunostaining and by terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) method in order to detect apoptotic cells. RESULTS: In the saline group statistically significant differences were detected between the baseline and immediate postacoustic overstimulation thresholds of click and 6 kHz stimuli. However, when the baseline and immediate postacoustic overstimulation thresholds of click and 6 kHz stimuli were compared in the erythropoietin injection group, no statistically significant difference was determined. Histopathologic evaluations demonstrated that erythropoietin decreased the amount of apoptotic cells in the cochlea. CONCLUSION: Erythropoietin is likely to prevent the acute threshold changes and decrease the amount of apoptosis in cochlea after acoustic overstimulation in rats.