Loudness Matching Research Articles

The Effect of Root-Mean-Square and Loudness-Based Calibration Approach on the Acceptable Noise Level

environment contains many background noises in everyday conversations, it is necessary to evaluate the noise tolerance. The Acceptable Noise Level (ANL) provides an approach to quantifying the maximum amount of background noise a listener is willing to put up with while listening to a target story without becoming tense. Exploring noise tolerance in speech perception, the study investigates how different calibration methods impact normal hearing participants’ monotic and dichotic ANL results. Methods: This investigation utilizes a pared-sample t-test for statistical analysis, adopting a comparative observational approach. This study applied the Persian version of the typical ANL test. Two approaches have equalized the target and background stimuli: Root Mean Squared (RMS) and loudness match calibration via Adobe Audition. Using these modified materials the Most Comfortable Level (MCL), the Background Noise Level (BNL), and ANL were compared in terms of RMS and loudness match calibration. Fifty normal persons aged (18–39), under the conditions of monotic and dichotic listening, participated in this study. Results: The statistical analysis using a paired-sample t-test revealed no significant differences in the outcomes of the ANL test between the calibrations of RMS and loudness matching under both monotic and dichotic listening conditions (p=0.31 and p=0.67, respectively). Conclusion: The study suggests that calibration procedures, namely RMS and Loudness matching, do not affect ANL in either monotic or dichotic conditions. Keywords: Loudness; calibration; acceptable noise level; root mean square

The Effectiveness of Cognitive Behavioral Therapy versus Notched Sound Therapy in Adults with Chronic Subjective Tinnitus and Normal Hearing.

Introduction Tinnitus can be distressing, and it affects the quality of life (QoL) through psychological and cognitive impairments. Cognitive behavioral therapy (CBT) and notched sound therapy (NST) are tinnitus management approaches aiming to reduce symptoms and improve QoL via two different mechanisms. The CBT attains the cognitive principle, whereas the NST initiates tinnitus habituation. Objective To evaluate the effect of CBT and NST and compare their results in the management of chronic subjective tinnitus. Methods The present prospective study involved 64 adults with normal hearing and chronic subjective tinnitus. They were subjected to history taking, basic audiological evaluation, and extended high-frequency audiometry at 10 and 12.5 kHz. The participants were divided into two equal groups, the first treated with CBT and the second treated with NST. The psychoacoustic measures of tinnitus and the Arabic Questionnaire for Tinnitus Reaction (Arabic-QTR) were used to monitor the outcomes of both therapies. Results Both groups showed significant reduction in tinnitus severity according to the Arabic-QTR and tinnitus loudness matching. Improvement in the Arabic-QTR was better in the CBT group, while tinnitus loudness improvement was better in the NST group. Conclusion Both CBT and NST are effective in the management of chronic subjective tinnitus. In a comparison of the effect of the two therapies, CBT was found to be more effective in decreasing tinnitus-related distress, whereas SNT was found to be more helpful in reducing tinnitus loudness.

A study on impact of tinnitus masking on psychophysical and tinnitus tuning curve in participants with hearing impairment suffering from severe tinnitus

Background: Tinnitus can be treated by using different pedagogies of management approaches in which tinnitus masking has been acclaimed most evidence-based approach. Psychophysical tuning curve and tinnitus tuning curve explored as least interested procedures in tinnitus research. This noteworthy but nonspecific psychophysical domain may throw a light on need of the present research. Aim of the study was to find out the effect of tinnitus masking on Psychophysical tuning curve and tinnitus tuning curve. Method: A total of 30 native Bengali speaking participants were included in this study, having mean age of 45.9 years and SD was 6.46. All the participants had unilateral subjective tinnitus with Mild to Moderately severe sensorineural hearing loss. Quasi-experimental research design was used. Dual channel audiometer (MAICO MA 53) with supra-aural TDH 39 headphone was used for psychoacoustic measurements of tinnitus (including pitch matching, loudness matching, minimum masking level etc.) and to provide tinnitus masking therapy. MATLAB version 9.5 was used to develop noise to assess PTC and TTC using Sennheiser HD 201 headphone routed through MAICO MA 53 audiometer via stereo jack and cable. Tinnitus masking therapy was carried out for 30 sessions by using regimen of MML +20 dB of masking level for 30 minutes duration for each session with matched pitch. PTC and TTC were measured before and 30 sessions-after tinnitus masking therapy. PTC was measured using 1000 Hz pure tone at 10 dBSLl as reference followed by four narrow band noise with centre frequency of 500 Hz, 1000 Hz, 2000 Hz, 4000 Hz pertaining to 312 Hz band width as developed by MATLAB software. TTC was measured using the same noise with reference to matched tinnitus pitch. All the above-mentioned conditions forced choice procedure was carried out in dBHL frame work. Results: Wilcoxon sign rank test was used at 95% confidence level to check the influence of tinnitus masking therapy on PTC and TTC measures. Significant changes were portrayed at 1000 Hz and 4000 Hz respectively in PTC measure and at 500 Hz, 1000 Hz, 2000 Hz and 4000 Hz respectively in TTC measures. Conclusion: This study preliminarily provides information regarding influence on tinnitus pitch domains which has been psychoacoustically systematically measured as PTC and TTC. These two psychoacoustic signatures may be treated as prognostic biomarker of tinnitus management in future using replicable research using different methodology or using statistical basis of data mining. At that point conclusive remarks may not throw a clear indication based on the results found in this study.

Numerical investigation of the vortical structures in the near wake of a model wind turbine

It is well known that the vortex system in a horizontal axis wind turbine wake is highly relevant in terms of fatigue loads and performance of wind turbines located in the wake of other wind turbines. The breakdown process of tip vortices particularly influences the mixing process of the low-speed wake region with the undisturbed flow outside the wake. As a collaboration with the Technische Universität Berlin (TUB), a major goal in a joint research is to study the effects involved in tip vortex breakdown. TUB designed a model turbine that will be towed through a large water tank to analyse and to control the tip vortex decay. To accommodate the measurement equipment, the ratio of blade length to nacelle length is unconventionally small, leading to uncertainty regarding the effect on the breakdown of the tip vortex. Due to the dimensions of the model wind turbine the root vortex system and the nacelle wake are not comparable to former studies and should therefore be investigated in detail. To do so computational fluid dynamics, in particular delayed detached eddy simulations, are conducted for the model turbine with the compressible flow solver FLOWer and the two-equation Menter-SST turbulence model. Two simulations are conducted with and without the nacelle. The results indicate that the root vortices propagate downstream and interact with each other. Additionally, these vortical structures are also influenced by the geometry of the turbine nacelle which causes faster decay of the root vortices compared to a configuration without the nacelle. However, the root vortex breakdown does not influence the tip vortices as the turbulent intensity matches for the area where tip vortices are present. In short, this investigation shows that the influence of the nacelle geometry and root vortex system on the tip vortices is negligible. Thus, the model wind turbine designed by TUB is suitable for the investigation of tip vortices.

Standard and Extend High-Frequency Audiometry in Sudden Sensorineural Hearing Loss: Impacts on Tinnitus and Mental Health.

To analyze the results of auditory assessment in standard (SA) and extended high-frequency (EHF) audiometry, associating the findings with sudden tinnitus and mental health of patients with unilateral sudden sensorineural hearing loss (SSNHL). Prospective, cohort study. Outpatient otology clinic in a tertiary care hospital. Patients experiencing unilateral SSNHL were evaluated with pure-tone audiometry performed at frequencies of 250 to16,000 Hz, tinnitus pitch and loudness matching tests, Tinnitus Handicap Inventory (THI), Analog and Visual Scale (AVS) for bothersome tinnitus, and the Hospital Anxiety and Depression Scale (HADS). Eighteen patients with unilateral SSNHL were assessed. After starting treatment, there was a significant improvement in the SA (71.1 dB to 50 dB; p < 0.001*) and EHF audiometry (64.5 dB to 54.4 dB; p < 0.001*) thresholds at 15 days, and this persisted at 30 days of follow-up. Significant improvements were seen for tinnitus in loudness, VAS, and THI and for mental health in the realms of anxiety and depression by HADS. Despite improvements in SA, persistent EHF hearing loss was accompanied by persistent tinnitus, but it was of diminished loudness. Despite improvement in pure-tone thresholds by SA, a subset of unilateral SSNHL patients did not experience hearing recovery in EHF thresholds and reported persistent tinnitus. We postulate that their diminished anxiety and better mental health may be related to both hearing improvement in standard audiometry and reduction in tinnitus loudness. This pilot prospective study investigates the utility of performing EHF audiometry to better understand outcomes in patients with SSNHL.

The Effectiveness of a Smartphone Application for Tinnitus Relief.

There has been a growing interest in the provision of smartphone- or internet-based tinnitus management. Studies have shown a positive impact of the smartphone applications on tinnitus symptoms. However, research into a relatively long-term effect of these applications on tinnitus relief as well as sound preferences has been sparse. This study explored the potential benefit of a tinnitus application in tinnitus relief over a period of six months. Twenty-two participants with subjective tinnitus were enrolled in the study. Puretone audiometry, tinnitus pitch and loudness matching, stress assessment, and questionnaires were completed at the initial visit and three and six months after the first visit. The participants used the tinnitus application for six months. A significant reduction in subjective tinnitus loudness and annoyance and subjective stress level was observed. The Tinnitus Handicap Inventory scores were also significantly decreased after six months. The participants also reported high satisfaction with the application. Music and environmental sounds were the most preferred sound stimuli. The findings of this study demonstrate the potential benefit of the tinnitus application for tinnitus improvement.

Psychoacoustic Characteristics of Tinnitus in Relation to Audiometric Profile

The aim of the study was to examine the relationship between tinnitus pitch and maximum hearing loss, frequency range of hearing loss, and the edge frequency of the audiogram, as well as, to analyze tinnitus loudness at tinnitus frequency and normal hearing frequency. The study included 212 patients, aged between 21 to 75 years (mean age of 54.4 ±13.5 years) with chronic subjective tinnitus and sensorineural hearing loss. For the statistical data analysis we used Chi-square test and Fisher’s exact test with level of significance p < 0.05. Tinnitus pitch corresponding to the frequency range of hearing loss, maximum hearing loss and the edge frequency was found in 70.8%, 37.3%, and 16.5% of the patients, respectively. The majority of patients had tinnitus pitch from 3000 to 8000 Hz corresponding to the range of hearing loss (p < 0.001). The mean tinnitus pitch was 3545 Hz ±2482. The majority (66%) of patients had tinnitus loudness 4–7 dB SL. The mean sensation level at tinnitus frequency was 4.9 dB SL ±1.9, and 13 dB SL ±2.9 at normal hearing frequency. Tinnitus pitch corresponded to the frequency range of hearing loss in majority of patients. There was no relationship between tinnitus pitch and the edge frequency of the audiogram. Loudness matching outside the tinnitus frequency showed higher sensation level than loudness matching at tinnitus frequency.

The Effect of Alpha-Lipoic Acid in the Treatment of Chronic Subjective Tinnitus through the Tinnitus Handicap Inventory Scores.

Tinnitus affects millions of adults. Many therapies, including complementary and alternative medicine and tinnitus retraining therapies, have been trialed, but an effective option, particularly for chronic subjective tinnitus (CTS), is still lacking. This study investigated the effects of alpha-lipoic acid (600 mg. per day for two months) on two groups of patients using a questionnaire. One group (A) was affected by tinnitus associated with likely cochlear dysfunction and metabolic syndrome, and the other (B) was composed of subjects with acoustic nerve lesions. All the patients were asked to complete the Italian version of the tinnitus handicap inventory (THI) to determine the overall degree of perceived annoyance at the beginning and end of therapy. Pure tone averages for speech frequencies and for high frequencies were computed, and psychoacoustic pitch and loudness matches were determined for each subject before and after treatment. The pure tone audiometry, pitch, loudness, and THI scores of both groups were reported. In group A, statistically significant differences were observed for the "functional" and "emotional" subscales. The total score of THI and the loudness of tinnitus were also significantly reduced. No statistically significant differences were observed in group B. These findings suggest a possible contribution of the antioxidant effect to the organ of Corti in subjects with metabolic syndrome and CST.

A Pilot Study to Evaluate a Residual Inhibition Technique in Hearing Aids for Suppression of Tinnitus.

Tinnitus acoustic therapy is defined as any use of sound where the intent is to alter the tinnitus perception and/or the reactions to tinnitus in a clinically beneficial way. The parameters of sound that may cause beneficial effects, however, are currently only theorized with limited data supporting their effectiveness. Residual inhibition is the temporary suppression or elimination of tinnitus that is usually observed following appropriate auditory stimulation. Our pilot study investigated the effects of a therapeutic acoustic stimulus that was individually customized to maximize residual inhibition of tinnitus and extend its duration to determine if there could be a sustained suppression of the tinnitus signal (i.e., reduced tinnitus loudness) and a reduction in the psychological and emotional reactions to tinnitus. This pilot study had two objectives: (1) to evaluate the feasibility of residual inhibition technique therapy through daily use of hearing aids and (2) to determine its effects by measuring reactionary changes in tinnitus with the Tinnitus Functional Index (TFI) and perceptual changes in tinnitus loudness. A total of 20 adults (14 males, 6 females; mean age: 58 years, SD = 12.88) with chronic tinnitus were enrolled in a four-visit study that consisted of the following: (1) baseline visit and initiation of the intervention period, (2) a 1-month postintervention visit, (3) 2-month postintervention visit and initiation of a wash-out period, and (4) a 3-month visit to assess the wash-out period and any lasting effects of the intervention. The intervention consisted of fitting bilateral hearing aids and creating an individualized residual inhibition stimulus that was streamed via Bluetooth from a smartphone application to the hearing aids. The participants were instructed to wear the hearing aids and stream the residual inhibition stimulus all waking hours for the 2-month intervention period. During the wash-out period, the participants were instructed to use the hearing aids for amplification, but the residual inhibition stimulus was discontinued. At all visits, the participants completed the TFI, study-specific self-report measures to document perceptions of tinnitus, a psychoacoustic test battery consisting of tinnitus loudness and pitch matching, and a residual inhibition test battery consisting of minimum masking and minimum residual inhibition levels. At the end of the trial, participants were interviewed about the study experience and acceptability of the residual inhibition treatment technique. Repeated measures analyses of variance (ANOVA) were conducted on the two main outcomes (TFI total score and tinnitus loudness) across all four visits. The results showed a significant main effect of visit on the TFI total score ( p < 0.0001). Specifically, the results indicated a significant reduction in TFI total scores from baseline to the 1-month post-intervention period, which remained stable across the 2-month post-intervention period and the wash-out period. The ANOVA results did not show a significant change in tinnitus loudness as a function of visit ( p = 0.480). The majority of the participants reported a positive experience with the study intervention at their exit interview. This pilot study demonstrated that residual inhibition as a sound therapy for tinnitus, specifically through the daily use of hearing aids, was feasible and acceptable to individuals suffering from chronic tinnitus. In addition, participants showed improvement in reactions to tinnitus as demonstrated by sustained reduction in TFI scores on average over the course of the treatment period. Achieving residual inhibition may also provide patients a feeling of control over their tinnitus, and this may have a synergistic effect in reducing the psychological and emotional distress associated with tinnitus. There was no significant reduction in long-term tinnitus loudness resulting from the residual inhibition treatment; however, the current pilot study may not have had sufficient power to detect such a change. The combination of tinnitus suppression and improved psychosocial/emotional reactions to tinnitus may result in a better quality of life in both the short and long term. A larger-scale study is needed to determine the validity of using residual inhibition as a clinical therapy option and to ascertain any effects on both perception and reactions to tinnitus.

Association of Vitamin D Deficiency in Patients with Tinnitus with Normal Audiogram.

In the present study we aim to evaluate serum vitamin D levels in participants having tinnitus with normal audiometric findings. Total 98 participants in the age range 20-70 year were included in the study. Participants underwent detail case history, ear examination, pure tone audiometry and impedance audiometry. 68 participants with subjective tinnitus for more than 3 months and with normal audiometric thresholds and "A" type tympanogram were included in study group and 30 participants without tinnitus in the control group. The participants fullfillng the inclusion criteria underwent thorough tinnitus evaluation which included administration of tinnitus severity index tinnitus handicap inventory, psychophysical evaluation of tinnitus (pitch matching, loudness matching) and assessment of Vitamin D levels. It was seen that the mean Vitamin D levels were significantly lower in study group, and out of 68 participants only 11 had optimal Vitamin D levels, 57 (83%) had Vitamin D levels less that 30mg/dl. In the control group 20 (66%) had vitamin D deficiency. The difference came out to be statistically significant. Our study suggests that there is a link between vitamin D and tinnitus, in view of these findings we recommend evaluating serum Vitamin D levels in patients of chronic idiopathic tinnitus, especially in adults with normal hearing. Our study suggests vitamin D deficiency may be one of the risk factor for tinnitus in people with normal hearing in the absence of other manifestations.

Effect of Tinnitus Retraining Therapy in Normal Hearing Individual with Subjective Tinnitus: An Observational Study.

This study was done to study the effect of Tinnitus Retraining Therapy (TRT) in Bilateral Normal Hearing Individual with subjective tinnitus and to evaluate the success of simplified TRT with relation to duration of tinnitus, the patient's age and state of mind. As on date there is no definite cure available for tinnitus, so current TRT focuses on reducing the impact of tinnitus on the patient's quality of life. This study included total fifty (50) participants with bilateral normal hearing sensitivity, who had reported to the department of ENT with a complaint of tinnitus in one or both ears. All the participants are active serving military personnel and their dependents of Indian Armed Forces. All the participants had undergone basic audiological test batteries to assess the hearing acuity followed by TRT and its components (TRT counselling and sound therapy) in randomized manner. Audiological test batteries include pure tone audiometry to make sure that the participants have normal hearing acuity in both the ears and then tinnitus matching i.e. pitch and loudness match and measurement of Uncomfortable Level (UCL) followed by sound therapy and counselling. There was significant improvement reported in impact of tinnitus after completion of six (06) months of TRT schedule. Amongst the participants, 40% reported with complete relief from tinnitus, 30% reported with remarkable benefit but they can still perceive the tinnitus, 20% reported with no benefit with TRT and rest of the 10% were not able to tell whether they have got any benefit or not. Normal hearing individual with tinnitus can be benefitted with TRT accompanied with counselling and the improvement in impact of tinnitus severity that ensued over six months of TRT appear to be vigorous with significant clinical outcomes.

Loudness in rooms and the sound strength parameter: Linking perception and physical acoustics

Loudness as a perceptual phenomenon has been extensively studied within psychoacoustics. In room acoustics, however, the psychoacoustical factors influencing loudness have yet to be incorporated into standard parameters such as sound strength (G). G is the decibel ratio of the integrated energy of a room impulse response (RIR) compared to the same source located 10m away in a free field. The purpose of this study was to determine how the physical RIR properties measured by G relate to perceived loudness in the same room. Listeners were asked to match pink noise presented anechoically to the perceived loudness of the same noise in a simulated room. Listeners could continuously adjust the level of the anechoic reference. Room simulations were rendered over a 36-channel loudspeaker array in an anechoic chamber. Loudness matches were performed for different room types, source-receiver distances, and source powers, which produced received sound levels between 35 and 85 dBA. Results show a relatively linear relationship between loudness and G. However, it is clear that G underpredicts loudness ratings at higher sound levels. This demonstrates a more complex relationship between G and loudness. Effects of room type and source-receiver distance appear to introduce additional complexity not represented by G.

Ginkgo biloba for tinnitus.

Ginkgo biloba for tinnitus.

Dependence of binaural gain for infrasound on interaural phase difference.

Increasing complaints about infrasound have generated interest in understanding its perception, including binaural effects. This study investigated the level difference between monaural and binaural presentation required for detection and equal loudness (binaural gain) for pure tones with frequencies of 8, 32, and 400 Hz and an 8 Hz sinusoidally amplitude-modulated tone with diotic 400 Hz carrier. Monaural stimuli were compared to binaural stimuli with interaural phase differences (IPDs) of 0°, 90°, and 180° in two experiments: absolute threshold measurements and loudness matching at 40 phons. The latter was repeated with transposed tones (400 Hz carrier multiplied by a half-wave-rectified 8 Hz sinusoid). When expressed as differences in sound pressure level, similar binaural gain was found across all stimulus types under the diotic condition. Confirming previous studies, the gain was larger at supra-threshold levels (40 phons) than at threshold. However, when the loudness-matching results were expressed as binaural gain with respect to the loudness level, they became 17.5, 11.2, and 5.8 phons for the 8, 32, and 400 Hz stimuli, respectively. Results for the 8 Hz pure tone and the transposed stimulus were IPD dependent.

Alterations in Brain Single-Photon Emission Computed Tomography Perfusion Pattern Pre- and Post-Transcranial Magnetic Stimulation in Tinnitus Participants

Background and Aim: It have been shown that changes in organization of high stimulation related to tinnitus in special areas in brain can be eliminated using protocols based on transcranial magnetic stimulation (TMS). The current study aims to assess the pattern of brain perfusion and effects of TMS on brain activity in tinnitus participants as measured by single-photon emission computed tomography (SPECT) as well as evaluate the efficacy of TMS on severity of tinnitus. Methods: This was a cross-sectional randomized clinical trial, which was performed in 15 patients that referred to tinnitus clinic of Rasoul Akram Hospital during March 2017 to April 2018. These participant were randomly divided into two groups of active treatment with TMS and placebo. In each studied group, the variables of the brain perfusion, tinnitus handicap index (THI), pitch-matching test, loudness match of tinnitus, minimum masking level, and residual inhibition were investigated for all included tinnitus participants before and after TMS. Results: In all tinnitus participants, we had increased uptake in temporal lobes (unilateral or bilateral). In active treatment group, SPECT variables in hotspots were significantly decreased in comparison with placebo group (P &lt; 0.05). Visual analog scale of tinnitus was significantly decreased in active group rather than placebo group (P = 0.023). Conclusion: Our findings showed that tinnitus patients have abnormal brain perfusion increased uptake in temporal lobes that decreased with treatment with TMS and therefore this modality could be an appropriate therapeutic option for the improvement of tinnitus in these patients and efficacy of therapy could assessed by brain perfusion scan as well.

Hearing aid effectiveness on patients with chronic tinnitus and associated hearing loss

ObjectiveOur study aimed to measure the effectiveness of using HA in reducing the disturbance caused by tinnitus. MethodsStudy was designed as a within-subjects clinical trial. Nineteen patients with chronic tinnitus and untreated sensorineural hearing loss were under counseling, HA fitting and 6 months follow-up. Tinnitus assessment was performed with Tinnitus Handicap Inventory (THI), Visual Analog Scale (VAS), pitch and loudness matching, and Minimum Masking Level measurements (MML). Resultsfollowing 6 months of HA use, a reduction in reported tinnitus and hearing handicap scales scores was observed both statistically and clinically. The pitch and loudness matching, as well as MML at the baseline and final evaluation were compared. MML’s thresholds reduced significantly after 6 months of HA use. ConclusionOur study has provided evidence that HA fitting is a valuable treatment strategy for chronic tinnitus relief and associated hearing loss subtype of patient. Level of evidence3.

Contraction of the stapedius and tensor tympani muscles explored by tympanometry and pressure measurement in the external auditory canal

It has been suggested that tensor tympani muscle (TTM) contraction may be involved in the development of ear-related pathologies such as tinnitus, hyperacusis and otalgia, called the tonic tensor tympani syndrome (TTTS). However, as there is no precise measure of TTM function under normal and pathological states, its involvement remains speculative. When the TTM or the stapedius muscle (SM) contracts, they both generate an increase of middle ear stiffness that can be measured through middle ear admittance. However, this technique cannot differentiate the contraction between the two muscles. On the other hand, the air pressure measured in a sealed external auditory canal can provide a measure of the eardrum displacement that may be able to differentiate SM from TTM contraction. TTM is attached to the malleus, and its contraction causes a retraction of the eardrum inside the middle ear cavity, while SM can have a small but reversed effect on TTM displacement. To investigate this issue, we compared the middle ear admittance and air pressure in a sealed external ear canal upon auditory stimulation (sMEMC) and voluntary middle ear muscle contraction (vMEMC). In addition, we assessed the perceptual effect of vMEMC, including pitch and loudness matching of the fluttering noise produced by vMEMC and the threshold shifts, were measured. Out of the 14 ears tested, sMEMC was associated with a decrease of admittance in 93% (mean peak average: -0.06 ml, SD:0.04) and an increase of air pressure in 29% of ears (mean peak average: 8.1 Pa, SD:5.1). No decrease in air pressure was found upon sMEMC. For vMEMC (n = 8 ears), decreases were found for both admittance and air pressure in 100% and 88%, with a mean peak average of -0.38 ml, SD: 0.54 and -149 Pa, SD:156, for admittance and pressure respectively. These results suggest that SM and TTM are involved in sMEMC and vMEMC, respectively. In addition, vMEMC was associated with perceptual effects including a low-frequency sound, pitch-matched at ∼30 Hz (>15 dB SL), and a low-frequency hearing loss of at least 10 dB between 20 and 200 Hz. In conclusion, admittance and air pressure recordings provide useful and complementary information on middle ear muscle contraction and can be used to explore the middle ear function.

Hair-cortisol and hair-BDNF as biomarkers of tinnitus loudness and distress in chronic tinnitus

The role of stress and its neuroendocrine mediators in tinnitus is unclear. In this study, we measure cortisol as an indicator of hypothalamus–pituitary–adrenal (HPA) axis alterations and brain-derived neurotrophic factor (BDNF) as a marker of adaptive neuroplasticity in hair of chronic tinnitus patients to investigate relationships with tinnitus-related and psychological factors. Cross-sectional data from chronic tinnitus inpatients were analyzed. Data collection included hair sampling, pure tone audiometry, tinnitus pitch and loudness matching, and psychometric questionnaires. Elastic net regressions with n-fold cross-validation were performed for cortisol (N = 91) and BDNF (N = 87). For hair-cortisol (R2 = 0.10), the strongest effects were sampling in autumn and body-mass index (BMI) (positive), followed by tinnitus loudness (positive) and smoking (negative). For hair-BDNF (R2 = 0.28), the strongest effects were hearing aid use, shift work (positive), and tinnitus loudness (negative), followed by smoking, tinnitus-related distress (Tinnitus Questionnaire), number of experienced traumatic events (negative), and physical health-related quality of life (Short Form-12 Health Survey) (positive). These findings suggest that in chronic tinnitus patients, higher perceived tinnitus loudness is associated with higher hair-cortisol and lower hair-BDNF, and higher tinnitus-related distress with lower hair-BDNF. Regarding hair-BDNF, traumatic experiences appear to have additional stress-related effects, whereas hearing aid use and high physical health-related quality of life appear beneficial. Implications include the potential use of hair-cortisol and hair-BDNF as biomarkers of tinnitus loudness or distress and the need for intensive future research into chronic stress-related HPA axis and neuroplasticity alterations in chronic tinnitus.

Tinnitus Assessment and Management: A Survey of Practicing Audiologists in the United States and Canada.

Tinnitus is a prevalent auditory disorder that can become severely debilitating. Despite decades of investigation, there remains no conclusive cure for tinnitus. Clinical practice guidelines (CPGs) are available for assessing and managing tinnitus. Even though such guidelines have been available for several years, the degree that audiologists adhere to them has remained unexplored. To determine what clinical practices are commonly used by audiologists in the assessment and management of the patient population with tinnitus, we administered an online survey to audiologists practicing in the United States and Canada. Among the audiologists that completed the survey and were included in the final analysis (n = 61), 70% were from the United States and 30% were from Canada. The audiologists represented a wide range of clinical experience (1-35 years). On average, those who completed the survey were relatively confident in their ability to assess and manage tinnitus patients indicated by a 0 to 100 Likert scale, with 0 representing no confidence (mean 72.5, ± 21.5 standard deviation). The most commonly reported tinnitus assessment tools were pure tone audiogram (0.25-8 kHz), administration of standardized questionnaires, and tinnitus pitch and loudness matching. Approximately half (55%) of audiologists indicated they include otoacoustic emissions, while less audiologists (<40%) reported measuring high-frequency thresholds, minimum masking levels, or loudness discomfort levels. The most common recommendation for tinnitus patients was amplification (87%), followed by counseling (80%) and sound therapy (79%). Few audiologists administer a truly comprehensive tinnitus assessment and ∼20% indicated not recommending counseling or sound therapy to manage tinnitus. The results are discussed in the context of what is explicitly indicated in published CPGs, professional organization recommendations, and recent findings of peer-reviewed literature.

A comparative study on photobiological effects of low-level laser therapy and tinnitus retraining therapy in patients with acoustic trauma-induced tinnitus

Background and Aim: Tinnitus is a subjective auditory symptom referred to the perception of sound in the absence of external stimuli, and there is no definite treatment for it. Rehabilitation methods and laser therapy have been recommen­ded used for its management. This study aimed to investigate the photobiological effects of low-level laser therapy (LLLT) and tinnitus retraining therapy (TRT) in patients with acoustic trauma-induced tinnitus. Methods: This clinical trial was conducted on 60 patients suffering from acoustic trauma-induced tinnitus for more than six months, divided into three groups of LLLT, TRT and LLLT + TRT. The Persian version of tinnitus handicap inven­tory (P-THI), visual analog scale (VAS), and loudness match (LM) scale were used to collect data. The collected data were analyzed in SPSS version.22 software. The effect of time, group and time × group on the scores of VAS, LM, P-THI and its subscales were examined. Results: There was a statistically significant diff­erence between LLLT + TRT and LLLT groups after intervention in terms of LM (p = 0.002) and VAS (p = 0.001) variables, but no statistical sig­nificance for P-THI and its subscales (p = 0.442) was found. Conclusion: Combination of LLLT and TRT, as a therapeutic protocol, is recommended due to their remarkable effects in reducing acoustic trauma-induced tinnitus symptoms. The use of LLLT method alone, however, is not recommen­ded due to its lower effects. Keywords: Tinnitus; low-level laser therapy; tinnitus retraining therapy; tinnitus handicap inventory; loudness matching; visual analog scale