Auditory and Vestibular Research

Implantable Hearing Aids: Expanding the Therapeutic Horizon of Auditory Rehabilitation

Masoud Motasaddi Zarand — Mon, 13 Apr 2026 03:45:07 +0000

The Article Abstract is not available.

Endocrine-Auditory Interactions: A Comprehensive Review of Hormonal Effects on Auditory Physiology and Pathology

Nasrin Gohari, Sepideh Ghasemi Ranjbar, Mahdi Khoshfetrat — Mon, 13 Apr 2026 03:49:09 +0000

Background and Aim: Hormones have various effects on different parts of the body,including the auditory system. This study aimed to review the effects of various hormoneson the auditory system.

Recent Findings: Various hormones, including estrogen, progesterone, prolactin,oxytocin, aldosterone, growth hormone, dopamine, Thyroxine (T4), Triiodothyronine (T3),parathyroid hormone, cortisol, norepinephrine, insulin, and melatonin, affect the auditorysystem. Estrogen, aldosterone, norepinephrine, melatonin, and oxytocin have a protectiveeffect against noise. Growth hormone has a positive impact on the development of hair cells.High or low levels of thyroid hormones and low levels of parathyroid hormone, insulin,melatonin, and dopamine can cause sensorineural hearing loss. High levels of cortisol cancause tinnitus and hyperacusis. Also, the presence of prolactin is related to early-onsetpresbycusis in women.

Conclusion: Hormones play an important role in the function of the auditory system andcan affect the development and maturation of auditory structures and their function. Anydisruption in hormonal balance may lead to temporary or permanent changes in the auditorysystem.

True Vs. Nonsense Word Auditory Memory and Sequencing Performance and Its Relation to Speech Perception in Noise

Somaraj Odeyar, Jim Saroj Winston — Mon, 13 Apr 2026 03:53:56 +0000

Background and Aim: Auditory memory and sequencing are vital components of centralauditory processing, crucial for functions including speech perception in background noise.This study compared performance in auditory memory and sequencing tasks using true andnonsense words and explored their relation to speech perception in noise abilities.

Methods: The study was conducted on 82 participants aged 18 to 24 with normal hearing.The participants completed auditory memory and sequencing tasks using true and nonsenseconsonant-vowel-consonant-vowel words. Stimuli were organised into three to eight-wordsequences and delivered through headphones binaurally. Responses were scored separatelyfor auditory memory and sequencing. Also, the participants were tested for speechperception in the presence of noise by computing the Signal to Noise Ratio required for50% correct recognition (SNR50).

Results: The study findings revealed that the participants performed significantly better ontrue words than nonsense words in the auditory memory (t=24.93, p<0.001) and sequencingtasks (t=27.25, p<0.001). A moderate negative correlation was evident between auditorysequencing and SNR50 for both true (r=-0.34, p=0.001) and nonsense words (r=–0.29,p=0.006). A subsequent logistic regression revealed that true word auditory sequencingscores can accurately predict speech perception in noise performance.

Conclusion: The findings show that cognitive-linguistic scaffolding enhances auditorymemory and sequencing, as seen in superior performance for true words. Auditorysequencing predicts speech perception in noise, while auditory memory does not,highlighting the complex link between scaffolding and speech perception in noise

Translation and Adaptation of the North Wind and the Sun Passage for Persian: A Phonetically Balanced Passage for the Persian Language

Mon, 13 Apr 2026 04:01:15 +0000

Background and Aim: Standardized speech passages are essential tools in audiologicalassessments, particularly for verifying hearing aid performance and evaluating speechperception. To ensure linguistic and cultural relevance, these passages must be adaptedto reflect the phonetic characteristics of the target language. This study focused on thetranslation and phonological adaptation of the North Wind and the Sun (NWS) passage intoPersian, aiming to provide a linguistically balanced and culturally appropriate stimulus foruse in speech-based verification protocols.

Methods: The NWS passage was translated into Persian with targeted phonetic and syntacticadjustments to ensure phoneme balance and linguistic coherence. Phoneme frequencies werecompared to reference Persian studies, and expert reviewers evaluated clarity, naturalness,and content validity using Content Validity Ratio (CVR) analysis. Revisions were madebased on feedback to optimize semantic integrity and phonetic distribution.

Results: The translated NWS passage contained 558 phoneme occurrences, with /a/ as themost frequent (63 times), aligning with Persian speech studies. The phoneme distributionstayed within the ±1 SD range, confirming linguistic consistency. Expert evaluationsyielded a CVR of 0.85, surpassing the 0.78 threshold, validating its relevance for speechresearch. The Face Validity Ration (FVR) of 4.7 affirmed clarity, phonetic balance, andnatural fluency in Persian speech assessments.

Conclusion: The translated NWS passage maintains phonetic balance with Persianlinguistic norms, ensuring accuracy in speech mapping and verification of hearing aids.Its adaptability for phonetic research and hearing aid validation highlights its relevance forPersian-speaking populations and cross-linguistic comparisons.

Comprehensive Evaluation of Post-Operative Balance Function Following Mastoidectomy in Patients with Chronic Otitis Media

Mon, 13 Apr 2026 04:09:07 +0000

Background and Aim: Patients with Chronic Otitis Media (COM) who undergo mastoidectomy sometimes experience imbalance, dizziness, and vertigo after the surgery. This study aimed to investigate the effects of mastoidectomy on the balance of patients with COM using standard and advanced balance tests.

Methods: The study was conducted in 2024 in Imam Reza and Ghaem Hospital affiliated with Mashhad University of Medical Sciences, Mashhad, Iran. Forty patients scheduled for mastoidectomy were enrolled over a 12-month period using a census method. Patients underwent balance tests before and after surgery. These tests included the video Head Impulse Test (vHIT), Subjective Visual Vertical (SVV), and posturography.

Results: Statistical analysis of the performance parameter under linear or sinusoidal plate movement conditions showed no significant difference before and after the surgery (p>0.05). Statistical analysis of the gain in the six semicircular canals in the vHIT test also showed no significant difference before and after the surgery (p>0.05). Similarly, statistical analysis of the deviation from the norm in the neutral position, –30° head tilt to the right, and –30° head tilt to the left showed no significant difference before and after the surgery (p>0.05).

Conclusion: The results of this study showed that mastoidectomy does not have a significant effect on balance tests, so performing it may not lead to severe balance disorders in patients with chronic otitis media who are candidates for mastoidectomy surgery.

Cervical Vestibular Evoked Myogenic Potentials in Older Adults: Comparison of Amplitude and Frequency Tuning Across Different Severity of Hearing Loss

Nikita Nanavati, Chitnahalli Shankarnarayan Vanaja — Mon, 13 Apr 2026 04:12:38 +0000

Background and Aim: Hearing loss and vestibular dysfunction frequently co-occur in older adults, affecting balance and mobility. Changes in the vestibular system can alter cervical vestibular myogenic potentials. This study aimed to investigate the amplitude and frequency tuning characteristics of cervical Vestibular Evoked Myogenic Potentials (cVEMP) across different degrees of hearing loss in older adults.

Methods: A cross-sectional study was conducted with 30 young adults with normal hearing and 30 older adults (50–70 years) with bilateral sensorineural hearing loss, categorized into mild, moderate and moderately severe hearing loss groups (n=10 per group). cVEMPs were recorded for 500 Hz, 1000 Hz, and 2000 Hz tone bursts. Amplitude and frequency amplitude ratios were analyzed using ANOVA with post hoc tests.

Results: Older adults with hearing loss showed significantly reduced amplitudes compared to young adults across all frequencies. Amplitude progressively decreased with increasing hearing loss severity, though it was not statistically significant between the hearing loss subgroups. Frequency amplitude ratios of persons with moderate and moderately severe hearing loss were significantly different from those of normal hearing. Frequency tuning shift towards 1000Hz was observed in mild hearing loss group. Responses were absent in a significantly higher proportion of persons with higher degree of hearing loss.

Conclusion: This study highlights saccular function in older adults across various degrees of hearing loss. It reveals tuning shift in cases of mild hearing loss, and a progressive decline in frequency-specific responsiveness with increasing hearing impairment

The Effect of Retinoic Acid on the Expression of Nestin, GATA Binding Protein 3, Neurogenin 1, and Microtubule- Associated Protein 2 Markers in Mesenchymal Stem Cells Derived from Human Adipose Tissue

Mon, 13 Apr 2026 04:20:15 +0000

Background and Aim: Hearing loss in developing countries drives interest in stem cell therapies, though underlying molecular mechanisms remain partly unclear. One key pathway in this process is the Retinoic Acid (RA) signaling pathway. This study aimed to evaluate the effect of RA on the expression of neural markers, including nestin, Neurogenin 1 (NGN1), Guanine-Adenine-Thymine-Adenine Binding Protein 3 (GATA3), and Microtubule- Associated Protein 2 (MAP2), in human Adipose-Derived Stem Cells (hADSCs).

Methods: hADSCs were purchased and treated with RA (1 μM) under standard conditions for 7 and 14 days. RNA was extracted using the FavorPrep™ RNA kit and converted to complementary DNA (cDNA). Nestin, NGN1, GATA3, and MAP2 gene expression was assessed using real-time Polymerase Chain Reaction (PCR) with Glyceraldehyde-3- Phosphate Dehydrogenase (GAPDH) as an internal control. Data analysis was conducted using the 2–ΔΔCt method.

Results: RA significantly increased the expression levels of nestin, NGN1, and MAP2 after 14 days compared to the control group (day 0). RA also increased nestin and MAP2 expression after 7 days, although these changes were not statistically significant compared to the control; moreover, RA acid induced morphological changes in hADSCs.

Conclusion: This study demonstrated that RA enhances the neural differentiation of hADSCs by upregulating the neural markers nestin, NGN1, and MAP2. These findings highlight the potential role of RA in neural differentiation and its clinical applications. These findings suggest that RA’s effects may be dose- and time-dependent, with one μM for 14 days enhancing neural marker expression.

Impact of High-Frequency Hearing Sensitivity on Speech Perception in Noise: Insights from the Persian Quick Speech-in-Noise Test

Mon, 13 Apr 2026 04:24:33 +0000

Background and Aim: Noise-Induced Hearing Loss (NIHL) is a prevalent occupational concern, affecting high-frequency hearing sensitivity, which may impair speech perception in noisy environments. This study investigates the relationship between high-frequency hearing thresholds (4000–12500 Hz) and speech perception in noise, using the Persian Quick Speech-in-Noise (Quick SIN) test. The aim was to determine how these thresholds and speech perception in quiet correlate with and predict speech perception difficulties in noise.

Methods: A cross-sectional study was conducted on 288 participants aged 18–60 at the Center for Research on Occupational Diseases, Tehran University of Medical Sciences, from March to August 2024. Participants underwent audiometric testing for conventional (250–8000 Hz) and extended high-frequency (12500 Hz) thresholds, Word Recognition Score (WRS), and the Persian Quick SIN test (basic and high-frequency lists). Pearson’s and Spearman’s correlations and multiple linear regression models evaluated relationships and predictive factors, with significance set at p<0.05.

Results: Strong positive correlations were observed between basic and high-frequency Signal-to-Noise Ratio (SNR) loss and hearing thresholds at 4000–12500 Hz (r/ρ=0.738– 0.84, p<0.001), with strong negative correlations with WRS (ρ=–0.756 to –0.785, p<0.001). Regression models identified 8000 and 12500 Hz thresholds, WRS, and education level as significant predictors of SNR loss (R²=0.764–0.812). High-frequency list SNR loss was significantly lower than basic list SNR loss (p<0.001).

Conclusion: High-frequency hearing sensitivity, particularly at 8000 and 12500 Hz, significantly impacts speech perception in noise. Integrating high-frequency audiometry and speech-in-noise testing into occupational health assessments can improve early detection and management of NIHL

A Language Neutral Nonsense Speech-in-Noise Test for Dravidian Language Speakers: Development and Psychometric Evaluation

Prajwal Kumar Eranna , Jayashree S Bhat, Aradith S — Mon, 13 Apr 2026 04:27:13 +0000

Background and Aim: Assessing Speech Perception in Noise (SPIN) in multilingualcontexts like India is challenging due to the lack of linguistically appropriate test materials.Recognizing the limitations of existing SPIN tests in multilingual and clinically diversesettings, this study addressed critical need by developing a language-neutral, nonsenseSPIN test material tailored for Dravidian languages.

Methods: Nonsense word lists in the consonant vowel consonant vowel format weregenerated using a random combination of common phonemes in the Dravidian languages(Kannada, Malayalam, Telugu, Tulu, Tamil). These lists were recorded, and the Signal-to-Noise Ratio required to achieve 50% Speech Recognition (SNR50) was used to selectoptimized lists based on a criterion of mean ±0.15 SD. The final lists were administeredto 50 normal-hearing individuals at 0 dB SNR. Language independence was evaluated bycomparing performance across speakers of the five languages. Further performance was alsoassessed across eight SNR levels to establish a psychometric slope function and goodnessof fit was assessed. To evaluate test–retest reliability, 12 participants were retested within aone-week interval.

Results: The study resulted in 4 final optimized lists based on SNR50 selection criteria andfurther analysis. Lists showed sensitivity to varying SNR levels, as reflected by consistentpsychometric function slopes. Comparable performance across language groups confirmedthe language-independent nature of the test.

Conclusion: Developed test provides audiologists with a reliable and standardized tool toassess SPIN. By eliminating the influence of familiarity and ensuring language neutrality,the test is well-suited for clinical use across speakers of Dravidian languages.

Effect of Audiometric Configuration on Binaural Temporal Fine Structure Sensitivity in Adults with Sensorineural Hearing Loss

Samira Bagheri, Parisa Rasouli Fard, Alireza Akbarzadeh Baghban — Mon, 13 Apr 2026 04:29:55 +0000

Background and Aim: Temporal Fine Structure (TFS) cues are crucial for pitchperception, sound localization, and speech understanding in noise. Hearing loss can impairTFS sensitivity, but the role of audiogram configuration remains unclear. Therefore, thisstudy aimed to compare binaural TFS sensitivity in adults with Sensorineural Hearing Loss(SNHL) having different audiogram configurations.

Methods: This comparative cross-sectional study included 47 adults (32 with slopingaudiograms, 15 with rising/flat audiograms) aged 18–50 with bilateral mild to moderateSNHL (26–55 dB HL). All participants had normal outer and middle ear status, were right-handed, and had no cognitive impairment. TFS sensitivity was measured using the TFS-Low Frequency (TFS-LF) test at 250, 500, and 750 Hz, and the TFS-Adaptive Frequency(TFS-AF) test at Interaural Phase Differences (IPDs) of 45° and 135°.

Results: For the TFS-LF test, average thresholds were lower in the sloping group at allfrequencies, but the difference between the two groups was not significant (p>0.05). For theTFS-AF test, thresholds at IPD 135° were significantly higher than at IPD 45° (p<0.001),but the difference between the two groups was not significant. Significant correlations wereobserved between the TFS-LF and the TFS-AF thresholds (r=–0.783, p<0.001).

Conclusion: There is no significant difference in TFS sensitivity between adults withsloping and rising/flat audiograms. Absolute hearing thresholds at various frequencies donot solely influence TFS sensitivity; factors such as cochlear health, neural timing, andindividual variability may also affect the outcome

Auditory Processing Rehabilitation Follow-Up through Speech-Evoked Auditory Brainstem Response in Contralateral Noise; A Case Report

Mohaddese Vahabi, Mohanna Javanbakht, Enayatollah Bakhshi — Mon, 13 Apr 2026 00:00:00 +0000

Background: Auditory Training (AT) is an effective intervention for Auditory Processing Disorder (APD), and its outcomes are usually assessed through behavioral and electrophysiological tests. Among objective tools, speech-evoked Auditory Brainstem Response (s-ABR) has been used to evaluate AT effects, and it has shown promise, but s-ABR recorded in contralateral noise —a method activating both afferent and efferent auditory pathways —has not been applied to monitor rehabilitation progress in APD.

The Case: Here we compare pre- and post-intervention different tests’ results of a 7-year- old boy with APD (with documented deficits in dichotic processing and speech-in-noise perception) to investigate which is the most appropriate tool for assessing rehabilitation efficacy. The case underwent behavioral and electrophysiological evaluations, including s-ABR with and without contralateral noise, before and after 15 sessions of targeted AT tailored to the child’s specific processing weaknesses. Post-training results revealed significant improvement in behavioral tests and questionnaire scores. S-ABR assessments also demonstrated improvements, including increased V/A slope as well as improvements in wave latencies and amplitudes, with more pronounced changes observed in recordings with contralateral noise.

Conclusion: This case highlights the novel use of s-ABR in contralateral noise as a promising objective tool for monitoring auditory rehabilitation in APD. While behavioral assessments remain the gold standard, this electrophysiological test may provide valuable complementary information, particularly for patients with limited behavioral test cooperation or when behavioral results are unreliable. As this case report involves a single child with APD, further studies are needed to validate these findings in broader APD populations