Background and Aim: Auditory temporal processing (ATP), the ability to perceive acoustic changes over time, is fundamental for communication. Deficits in ATP underlie various auditory processing disorders. This review focuses on the electrophysiological correlates of ATP deficits in key clinical populations, including auditory neuropathy, dyslexia, and age-related hearing loss. The aim was to establish a hierarchical neurophysiological framework for understanding these deficits, from the brainstem to the cortex, using objective electrophysiological measures.
Recent Findings: Evidence reveals a systematic shift in neural encoding. The brainstem employs precise temporal coding, measured by the Auditory Brainstem Response (ABR) and Frequency-Following Response (FFR). In contrast, higher cortical centers utilize rate-based and cognitive coding for periodicity, captured by cortical Event-Related Potentials (ERPs) like the N1-P2 complex and Mismatch Negativity (MMN). This framework allows for the objective localization of dysfunction, such as neural dyssynchrony in auditory neuropathy. Critically, the system shows experience-dependent plasticity; targeted auditory training can normalize cortical responses and enhance subcortical encoding.
Conclusion: Electrophysiological measures provide a critical, non-invasive window into ATP. They offer validated biomarkers for diagnosing disorders, objectively validating rehabilitation efficacy, and guiding personalized intervention. Future translation into clinical practice requires standardized protocols and integrated multi-level assessments.

Background and Aim: Autoimmune Diseases (ADs), marked by immune system dysfunction and self-targeting immune responses, can damage the auditory system, leading to symptoms like tinnitus and sensorineural hearing loss. This study explores the prevalence, underlying mechanisms, diagnosis, and treatment of tinnitus within the context of ADs.
Recent Findings: This narrative review identified relevant articles through searches of Web of Science, Science Direct, PubMed, and Google Scholar, using keywords related to both tinnitus (e.g. "Tinnitus", "Ringing") and ADs (e.g. "Autoimmune Disease", "Multiple Sclerosis", "Lupus"). This review found a significant prevalence of tinnitus across various ADs. Autoimmune inner ear disease exhibited the highest tinnitus rates (50–95.7%), followed by sarcoidosis (61%) and Susac’s syndrome (54–77%). Systemic lupus erythematosus (6.7–44.4%), Sjögren's syndrome (10.1–41.7%), and multiple sclerosis (up to 30%) also showed notable tinnitus prevalence. The main mechanisms involve vasculitis affecting inner ear vessels, immune complex accumulation, demyelination of auditory pathways, and hair cell damage from ototoxic immunosuppressants (e.g. cyclosporine). Regarding tinnitus treatment, corticosteroids (e.g. prednisone) offer potential benefit, though symptom relief is often temporary. Biologics (e.g. rituximab, adalimumab) have also been explored with varying degrees of success in specific cases.
Conclusion: Due to the significant prevalence of tinnitus observed in ADs, it is recommended that relevant specialists consider incorporating hearing assessments, particularly those specific to tinnitus, into their evaluation protocols. This may facilitate earlier diagnosis and ultimately lead to more appropriate and timely management and rehabilitation strategies.

Background and Aim: Numerous studies have investigated the linguistic characteristics of Persian-speaking children with hearing impairment. Given the variability of findings across these studies, a systematic review is required to both identify research gaps and synthesize existing results. This systematic review aimed to answer the following question: in Persian-speaking children with hearing impairment compared to typically hearing Persian-speaking children, what is the profile of linguistic skills (phonology, morphosyntax, semantics, pragmatics) and metalinguistic skills (phonological awareness, syntactic awareness, semantic awareness)?
Recent Findings: Persian-speaking children with hearing impairment experience significant delays across most linguistic domains, particularly in phonetics/phonology (55% of studies), morphosyntax (16%), and semantics/pragmatics (13%). The most consistent deficits were observed in vowel production and perception, phonological awareness, grammatical omissions, tense marking errors, and comprehension of non‑literal meanings. Children with cochlear implants outperformed hearing aid users, and early implantation (before age 2) was associated with more favorable outcomes.
Conclusion: Persian-speaking children with hearing impairment demonstrate significant and persistent delays in both linguistic and metalinguistic skills compared to typically hearing peers. Early cochlear implantation and linguistically rich educational environments (e.g. mainstream schools) are associated with better language outcomes. Clinically, comprehensive language assessments should include both receptive and expressive skills, with targeted interventions focusing on phonological awareness, morphosyntax, and pragmatic abilities. Future research should prioritize neglected age groups (6–8 years and 10–15 years) and the understudied semantic-pragmatic domain.

Background and aim: Motion sickness, characterized by conflicting sensory signals, negatively impacts attention and cognitive functions. This study investigated the effects of motion sickness on auditory spatial perception and working memory in adults with normal hearing.
Methods: A Standard group comparison was conducted on  100 adults with motion sickness, classified into three groups—normal-minimal, mild-moderate, and severe—based on Motion Sickness Susceptibility Questionnaire (MSSQ)-short scores. Standardized assessments were used to evaluate auditory spatial perception, including interaural time difference (ITD), interaural level difference (ILD), and the Virtual Acoustic Space Identification (VASI) test, along with working memory assessed through the forward digit span and 2-back test. ITD and ILD tests involved a discrimination task using psychoacoustic staircase procedure, VASI required identification of virtual locations within head, and memory tasks involved repetition digits and 2^nd last digit in sequence, in forward task, and 2-back tasks, respectively.
Results: Participants with motion sickness (mild-moderate and severe groups) performed significantly poorer (p < 0.05) than those without on the VASI test, forward digit span, and 2-back. A moderate negative correlation was observed between MSSQ-short and VASI scores. Discriminant function analysis (DFA) revealed that participants with severe motion sickness could be categorized from the other two less severity groups (normal-minimal, mild-moderate), with VASI and forward digit span emerging as the most sensitive indicators of motion sickness induced changes in spatial and working memory.  
Conclusion: Findings underscores the importance of monitoring motion sickness, as it can impair spatial processing and working memory tasks in auditory domain.

Background and Aim: Posterior fossa lesions often present with slowly progressive hearing loss, making diagnosis challenging. Pure-tone audiometry (PTA) and the Auditory Brainstem Response (ABR) are essential tools for assessing retro-cochlear involvement and establishing hearing thresholds. This study aimed to assess the audiometric profiles of patients with posterior fossa lesions and ascertain whether they could distinguish between different types of lesions.
Methods: A cross-sectional study was conducted on 36 patients aged 10-65 years. Each participant underwent otoscopic examination, tympanometry, PTA, and ABR testing.  The data were analyzed using the chi-square and Kruskal-Wallis tests in SPSS version 25, with Cohen's f and Cramer's V for effect size. A p-value of less than 0.05 was considered significant.
Results: Lesion types showed a strong correlation with clinical presentation. Vascular loops were associated with tinnitus, vestibular schwannomas with facial numbness and hearing loss, and meningiomas with vertigo and headache. Schwannoma cases exhibited significantly higher ipsilateral hearing thresholds, especially at high frequencies (p < 0.05). ABR results varied by lesion type: vascular loops mostly caused delayed wave III, meningiomas produced prolonged wave V and I–V intervals, while schwannomas showed the most severe abnormalities, including missing or delayed waves and interpeak intervals. Contralaterally, only schwannomas displayed ABR delays in wave V and I–V interval.
Conclusion: Lesion differentiation was aided by the clinical and audiological characteristics of posterior fossa lesions. ABR offers objective data on retro-cochlear involvement, while PTA identifies changes in hearing threshold. When used together, they improved diagnostic precision and patient care.

Background and aim: Contraversy exists regarding the link between the psychoacoustical measures and the perceptual rating of musical skills.  The study aimed to determine whether the perception of musical abilities, as rated by music teachers, is associated with specific psychoacoustical abilities.
Methods: Twenty-seven children who had undergone Carnatic music training for a duration of 2 months to 1 year were assessed using three psychoacoustical tests: Gap Detection Test (GDT), Duration Discrimination Test (DDT), and Difference Limen of Frequency (DLF) tests.  Two music teachers, with different teaching experiences, rated their pitch, rhythm, tempo, auditory memory, and overall musical abilities.
Results: The inter-rater reliability was found to be excellent, suggesting that the ratings given by both teachers were similar.  A Spearman’s rank correlation test showed a moderate significant correlation between rating scores awarded by the teachers and the thresholds obtained by the trainees on the psychoacoustical tasks.  These correlations were seen between temporal resolution (GDT) with the rating of the teachers for auditory memory (r=-.55, p=.003), and between frequency discrimination at mid-frequency stimuli (DLF at 1000 Hz) and the rating by the teachers for tempo (r=-.62, p=.000). A principal component analysis also grouped GDT and DLF at 1000 Hz with the ratings of the teachers, substantiating the findings of the correlation.
Conclusions: The findings indicated that music teachers are able to provide information only on a few acoustical aspects when rating music trainees.  Hence, to get more specific information about the musical abilities of trainees, they should be evaluated using psychoacoustical measures.

Background and Aim: Speech audiometry assesses functional hearing beyond pure-tone thresholds, reflecting real-world speech perception. The present study compared whole-word and phoneme scoring methods for the Persian SBMU-1 monosyllabic word lists presented in speech-spectrum noise to determine their psychometric equivalence and sensitivity to signal-to-noise ratio (SNR) changes.
Methods: Twenty-two young adults with normal hearing participated. SBMU-1 consonant–vowel–consonant (CVC) words were presented binaurally at six SNRs (−5, 0, +5, +10, +15, +20 dB) in speech-spectrum noise at 60 dB HL. Recognition performance was analyzed using whole-word and phoneme scoring. List equivalency and scoring effects were examined using Friedman and Wilcoxon signed-rank tests with Bonferroni correction.
Results: Speech recognition improved systematically with increasing SNR for both scoring methods. Phoneme scoring consistently yielded higher scores than whole-word scoring, especially under low SNRs, revealing a 10–20% performance advantage. At high SNRs, the two methods converged. Across lists, differences were minor and list-specific, confirming the general equivalency of SBMU -1 lists in noise.
Conclusion: Phoneme scoring provides a more sensitive measure of perceptual performance in noise by capturing partial recognition, whereas whole-word scoring better represents functional communication ability. The SBMU-1 word lists are psychometrically balanced and suitable for both clinical and research applications in Persian speech audiometry.

Background and Aim: Previous research has linked personality traits to noise perception, yet the role of temperament, a fundamental determinant of emotional and sensory processing, remains insufficiently explored. This study aimed to examine the impact of various temperament types on hyperacusis, noise sensitivity, and noise annoyance among industrial workers.
Method: A cross-sectional study was conducted among 320 participants aged 20–60, selected via strict criteria. Variables were assessed using validated questionnaires, including Mojahedi Temperament, Weinstein Noise Sensitivity, Noise Annoyance, and Khalfa Hyperacusis. Data were analyzed using SPSS, with descriptive statistics, correlation, ANOVA, and MANCOVA employed for relationships and group differences.
Results: The results indicated that Melancholic individuals exhibited the highest hyperacusis (Mean = 6.01), sensitivity (Mean = 7.37), and annoyance (Mean = 8.19), whereas phlegmatic individuals showed the lowest sensitivity (Mean = 2.82,) and annoyance (Mean = 3.16). The dryness-wetness temperament dimension correlated positively with hyperacusis (r = 0.275, p < 0.01) and annoyance (r = 0.184, p < 0.05), indicating greater noise reactivity in individuals with drier temperaments. The effect of temperament on hyperacusis (η² = 0.11) was stronger than its impact on sensitivity (η² = 0.03) and annoyance (η² = 0.07).
Conclusion: In conclusion, this study highlights the significant role of temperament in shaping individuals' responses to noise, with melancholic and choleric individuals exhibiting the highest levels of noise sensitivity and annoyance, and phlegmatic individuals reporting the lowest levels. These findings underscore the necessity of personalized noise mitigation strategies in occupational settings to protect worker health.

Background and Aims: Aging leads to noticeable functional changes in central auditory processing and dichotic function. The aim of this study was comparison of dichotic function between young and elderly people, as a factor of Stimulus Onset Asynchrony (SOA).
Methods: Persian syllables were presented dichotically to the participants. The onset time of the concurrent stimuli differed from 0 to 150 ms between the right and left ear. The effects of SOA changes (from 0 to 150 ms) were investigated in 20 normal- hearing young adults (aged 18 to 29 years) and 20 elderly individuals (aged 60 to 75 years) The Binaural (Both) Ear Correct (BEC%) score, as an indicative of dichotic performance, was measured.
Results: The BEC% scores decreased as SOA was reduced in both groups. However, this decline was more pronounced and significant in the elderly group. In contrast, young adults achieved higher BEC% scores across all SOA levels compared with the elderly individuals.
Conclusion: The reduction in BEC% scores in elderly individuals (particularly at lower SOA levels), indicates a decline in central auditory processing function in this group. This study highlights the impact of aging on central auditory processing and dichotic function, which could be implemented in designing and updating rehabilitative programs.

Background and Aim: Early intervention with cochlear implantation for deaf children helps them acquire receptive and expressive language. Word learning is one aspect of language acquisition. The current study aimed to evaluate receptive vocabulary knowledge of deaf children who had received cochlear implant (CI) compared to their normal-hearing (NH) peers.
Methods: This is a descriptive-analytical study with a cross-sectional design that  was conducted on  90 Persian-speaking children (30 with CIs and 60 with normal hearing). The hearing age (HA) of children with CIs ranged from 2 to 57 months, and their chronological age (CA) was in the range of 32-71 months. The Persian version of the Peabody picture vocabulary test (RPVT-P) was used to evaluate the children’s vocabulary knowledge. The t-test and Pearson’s correlation test were used to analyze and compare the data. 
Results: There was a significant relationship between the total RPVT-P score and CA in both NH children (r= 0.842, p<0.001), and CI children (r = 0.824, p<0.001). There was a significant relationship between the total RPVT-P score and HA in children with CI (r = 0.658, p<0.001). There was a significant difference between the two groups of children in the scores of each RPVT-P item (p<0.001).
Conclusion: Persian-speaking children with CI gradually develop their receptive vocabulary knowledge, but they do not reach the same level of skills as their NH peers. Children with CI can learn various vocabularies.
Key words: Cochlear implants, deaf, hearing impairment, receptive language, vocabulary

Background and aim: Tinnitus is a persistent perception of sound without an external source and is often accompanied by emotional distress. Tailor-Made Notched Music Therapy (TMNMT) and Binaural Beat Stimulation (BBS) are non-invasive auditory approaches proposed to alleviate tinnitus symptoms. This study compared the effects of TMNMT alone and TMNMT combined with BBS in adults with chronic subjective tinnitus.
Methods: In this randomized controlled trial, 24 adults with chronic tinnitus were allocated to either the TMNMT group or the TMNMT + BBS group. Individualized music files were created by removing the tinnitus frequency band; in the combined group, an 8-Hz alpha-range binaural beat was embedded at -20 dB. Participants listened to the audio stimuli twice daily for four weeks. Outcomes included the Tinnitus Handicap Inventory (THI), Beck Depression Inventory (BDI), and Visual Analog Scales for tinnitus Loudness (VAS-L) and Annoyance (VAS-A).
Results: Both groups showed significant improvement across all outcome measures (p < 0.01). Greater mean reductions were observed in the TMNMT + BBS group for THI (Δ = 17.33 ± 13.11 vs. 9.00 ± 8.16) and BDI (Δ = 4.08 ± 1.79 vs. 1.83 ± 1.26), though between-group differences were not statistically significant. Effect sizes (Cohen’s d = 0.76-1.46) favored the combined intervention.
Conclusion: TMNMT and TMNMT + BBS effectively reduced tinnitus-related distress and depressive symptoms. The addition of binaural beats produced stronger clinical gains; however, these differences were not statistically significant and therefore should be interpreted cautiously. Larger trials with extended follow-up are recommended.
Trial Registration Number: IRCT20250215064735N1

Background and Aim: Auditory Processing Disorder (APD) impairs auditory information processing specially affecting speech understanding in noise. Early screening is essential to address learning and social challenges. The Teacher’s Evaluation of Auditory Performance (TEAP) is a validated teacher-based APD screening tool. This study translated TEAP into Persian (P-TEAP), evaluated its psychometric properties, and assessed correlations with the Scale of Auditory Behaviors (SAB) and Bamford-Kowal-Bench (BKB) sentence test.
Methods: The TEAP was translated trough the International Quality of Life Assessment method. Face and content validity were assessed. Teachers completed both the P-TEAP and the SAB, while parents completed the parent version of SAB, for 243 children aged 7–13 years including 93 males, who underwent hearing screening and BKB testing.
Results: All items were clear and relevant (CVR=0.92, CVI=1). Cronbach’s α was 0.905 for the total scale. Test-retest reliability was excellent (ICC=0.99). Convergent validity was supported by correlations with SAB-T (r=0.901), SAB-P (r=0.716), BKB right ear (r=-0.614), and BKB left ear (r=-0.590). ROC analysis identified a cut-off score of 6 with 95.0% sensitivity and 68.3% specificity using BKB as reference, and a cut-off of 6 with 98.5% sensitivity and 92.1% specificity using SAB-T as reference.
Conclusion: The P-TEAP is a valid and reliable tool for screening APD in Persian-speaking children. Its robust psychometric properties and correlations with SAB and BKB support its use in research and clinical settings.

Background & Aim: Hearing impairment in childrn can affect language acquisition and consequently lead to delays in speech and language skills. The purpose of this study was to examine the relationship between phonological working memory (PWM) and mean length of utterance (MLU) in normal and hearing-impaired Persian-speaking children.
Methods: The study included 27 children with profound hearing loss (mean age = 5.42 ± 0.31 years) and 27 typically developing children (mean age = 5.62 ± 0.36 years), matched for age range (5–6 years) and gender (12 boys, 15girls). A nonword repetition task was used to assess PWM, and 50 utterances were selected from the obtained discourse samples to evaluate MLU.
Results: The relationship between these two variables was compared across the two groups. A strong and significant correlation was found between PWM and MLU in children with profound hearing loss (HL). Additionally, the correlation in typically developing children was moderate and significant.
Conclusion: A strong correlation between PWM and MLU was found in children with HL, whereas a moderate correlation was observed in typically developing children. These findings indicate the relevance of PWM to MLU in both groups, with a stronger association in children with hearing loss, without implying causality.

Background and Aim: Inflammatory processes play a key role in vestibular neuritis (VN) pathogenesis, and recent research has associated vitamin D deficiency with various audio-vestibular conditions, including reduced serum 25-hydroxyvitamin D [25(OH)D] concentrations in individuals with acute VN. Given its notable immunomodulatory and anti-inflammatory actions, vitamin D may serve as an adjunct to enhance VRT outcomes. The present study examined the impact of combining 25(OH)D supplementation with VRT on vestibular function among patients with VN.
Methods: In this randomized controlled trial, 41 patients with VN were allocated into two groups. The VRT group (n=20) received individualized vestibular rehabilitation for 30 minutes, three times daily for 12 weeks. The VRT+VitD group (n=21) received the same VRT protocol plus a weekly oral dose of 50,000 IU of 25(OH)D for 12 weeks. Outcomes were assessed pre- and post-intervention using the Dizziness Handicap Inventory (DHI), Vertigo Symptom Scale-short form (VSS-sf), and affected canal vestibulo-ocular reflex gains with video head impulse test, within- and between-groups.
Results: Both groups improved significantly across all measurements. The VRT+VitD group showed a normal serum level of vitamin D post-intervention (39.36±3.06; p<0.001) and greater improvements in subjective symptom reduction (DHI; p=0.023; partial η²=0.126), and VOR gains (p<0.001 with partial η²=0.459, 0.576, and 0.197 for lateral, anterior, and posterior canals, respectively) compared to the VRT group.
Conclusion: Correcting vitamin D deficiency supports and potentially enhances the effects of vestibular rehabilitation in patients with vestibular neuritis, although these outcomes should be interpreted with caution due to the study’s limitations.

Background and Aim: Speech perception is severely impaired by sensorineural hearing loss (SNHL) and background noise. This study compared two newly developed Persian speech-in-noise tests, the Persian dynamic spatial quick speech in noise (P-DSQSIN) test and the Persian hearing in noise test (P-HINT), to evaluate the clinical utility of both in adults with SNHL.
Methods: Fifty subjects with moderate to moderately severe SNHL (aged 18–50) and twenty-five normal hearing (NH) subjects (aged 18–25) participated. They were assessed using both the P-DSQSIN and P-HINT. Additionally, the Persian spatial hearing questionnaire (P-SHQ) and the Persian speech, spatial and qualities of hearing scale (P-SSQ) were used to correlate objective test results with subjective perceptions of speech difficulties in noise.
Results: Significant differences (p<0.05) were found between the two groups across tests and questionnaires. The P-DSQSIN test demonstrated several advantages over P-HINT concerning clinical use, including setup complexity, ease of administration, and scoring. The results of the two tests showed a moderate positive correlation (r=0.693, p<0.001). In the SNHL group, the results revealed moderate significant positive correlations between the P-DSQSIN SNR loss and P-HINT SNR with the P-SHQ (r = 0.538, p < 0.001 and r=0.427, p =0.007) and P-SSQ questionnaire scores (r = 0.647, p < 0.001 and r = 0.348, p = 0.015).
Conclusion: Both tests assess the listener’s ability to hear in background noise. However, the P-DSQSIN test is a more sensitive measure of speech perception in noise than the P-HINT in subjects with SNHL.

Background and Aim: To investigate if the effectiveness of digital noise reduction (DNR) in improving speech recognition scores and reducing listening effort in younger and older adults with moderate sensorineural hearing loss is associated with envelope distortion caused by the DNR algorithm used in hearing aids.
Methods: Participants included 17 younger adults (18-45 years) and 20 older adults (51-70 years) with flat moderate sensorineural hearing loss (SNHL). The benefit of a modulation-based DNR algorithm was assessed using sentences (0° azimuth) presented in speech noise (180° azimuth) at +4 dB SNR. The Envelope Difference Index was calculated using the algorithm, and correlations between DNR benefits and envelope distortion were analysed.
Results: DNR enhanced speech-in-noise recognition scores for younger adults, but it did not have the same effect for older adults. Listening effort, measured by final-word recall scores, improved significantly in both younger and older adults in the DNR group. However, there was no significant difference in EDI between the groups. No correlation was found between the magnitude of the envelope difference index and DNR benefits on speech recognition and listening effort in younger and older adults. 
Conclusions: Digital noise reduction improved speech recognition in noise for younger adults but not older adults with moderate hearing loss, though both groups showed reduced listening effort, with benefits unrelated to signal envelope distortion.

Background and Aim: The contributions of auditory and cognitive factors to speech perception in noise in the elderly are well studied; however, the roles of adaptive mechanisms, such as Rapid Adaptation (RA) and Perceptual Learning Ability (PLA), are less well explored. This study examined the relative contributions of RA, PLA, auditory processing and cognitive abilities towards speech perception in noise in the elderly.
Methods: Seventy-eight participants aged 60–75 years were divided into three groups: elderly with normal hearing (ENH), elderly with hearing impairment (EHI), and elderly with hearing aid (EHA). Auditory processing, cognitive abilities, and speech perception in noise were assessed. RA was quantified as the learning slope during exposure to time-compressed speech, and PLA was measured as retained improvement from pre- to post-training after a 2–4-day interval.
Results: Significant group differences were observed across auditory processing, cognitive measures, baseline speech perception, RA, and PLA. RA differentiated normal-hearing participants from hearing-impaired participants but did not differentiate between hearing-impaired participants. PLA emerged as the strongest predictor of speech perception in noise in the hearing-impaired groups, accounting for substantial variance beyond auditory and cognitive factors, whereas auditory measures predominated in the normal-hearing group.
Conclusion: RA and PLA make distinct contributions to speech perception in noise among elderly listeners. Adaptive mechanisms were not influenced by the hearing aid use, highlighting the need for rehabilitation approaches that incorporate targeted perceptual learning–based auditory training along with amplification.

Background and Aim: The Minimum Audible Angle (MAA), defined as the minimum perceivable angular disparity among sound sources, is the most frequently used measure of spatial acuity in psychophysics. While conventionally free-field loudspeaker arrangements measure MAA, virtual auditory methods offer flexible alternatives. The study aimed to determine which stimulus characteristic—intensity level, type, or duration—most influences MAA in normally hearing young adults.
Methods: Using a repeated-measures design with 30 healthy adults aged 18-30 years, spatialized stimuli generated by the 3D Tune-In Toolkit were presented over headphones at three levels (45-, 55-, and 65-dB SPL), durations (250, 500, and 1000 ms), and stimulus types (complex tone, pure tone, and white band noise). MAA thresholds were determined using a psychometric staircase procedure with a two-down one-up rule in a three-interval forced-choice task.
Results: Three-way repeated-measures ANOVA showed significant main effects of stimulus type and intensity level (p < 0.001), while duration had no significant effect but interacted with level and stimulus type (p < 0.001). Post hoc comparisons revealed eight significant stimulus-type pairs and nine level pairs after Bonferroni correction (α = 0.02), with complex tones and higher intensity producing lower MAA thresholds. Multiple regression showed only stimulus intensity significantly predicted MAA.
Conclusion: The findings demonstrate that higher intensities yield optimal spatial acuity and confirm the reliability of virtual headphone-based methods.

Abstract

Background and Aim: Tinnitus is common but varies in severity. Evidence suggests central mechanisms drive handicap. This study estimates adult tinnitus prevalence and Tinnitus severity in Mashhad and examines links between Tinnitus Handicap Inventory (THI), hearing handicap, pure-tone averages (PTA), WHO impairment grades, and age-corrected NIHL-like patterns.

Methods: This is a population-based cross-sectional study (May 2024–March 2025) included a stratified cluster random sample of 2,186 adults aged 20–85, who completed Persian THI, and hearing handicap inventories. They underwent PTA and speech discrimination testing. Hearing graded per WHO. NIHL patterns screened using Coles–Lutman–Buffin criteria applied to uncorrected and ISO 7029 age-corrected thresholds. Analyses used non-parametric tests; robust and median quantile regression for continuous outcomes; beta-binomial GLM for speech discrimination; proportional-odds logistic regression for WHO grades; and logistic regression for NIHL; models adjusted for age and sex.

Results: Tinnitus prevalence was 19.9%; 67.8% had slight/mild handicap, and ~3% had THI ≥38. THI correlated moderately with hearing handicap (ρ=0.361) and weakly with PTA (ρ=0.122). Each THI point increased the odds of worse WHO grades by 1.4% and predicted poorer speech discrimination (~14% lower odds per 10-point increase; OR≈0.86). THI did not predict age-corrected NIHL classification (OR=0.998; non-significant). THI, more than thresholds, predicted perceived hearing handicap.

Conclusions: In Mashhad, tinnitus is common yet low-impact, with only 1 in 30 adults experiencing clinically significant handicap. This supports a neurocognitive framework emphasizing limbic/attentional factors over audiometric patterns, suggesting that routine speech testing should accompany tinnitus assessments.

Background and aims: Many parents rely on professionals for information to decide their children’s initial communication mode. Although sign language is accessible to all children who are deaf, spoken language remains inaccessible to many. Therefore, providing evidence-based professional counseling is crucial to guiding parents in leveraging this golden window for language acquisition. This study aimed to assess the knowledge, attitudes, and practices (KAP) of professionals regarding sign language.
Method: This cross-sectional study involved 199 audiologists (49.2%) and speech-language pathologists (50.8%) who completed an online KAP questionnaire. The survey assessed three domains of sign language in Individuals who are deaf and hard-of-hearing . The data were analyzed using descriptive and inferential statistics, including multiple linear regression, to identify the factors influencing each domain.
Results: There was a strong positive correlation between KAP (p<0.001). Misconceptions, such as the belief that “sign language hinders the speech learning ,” were common.   Speech-language pathologists demonstrated better performance in using sign language than audiologists (p<0.001), and younger practitioners exhibited higher levels of knowledge and practice, suggesting the impact of recent training.
Conclusion: This study showed persistent professional beliefs that sign language may reduce children’s motivation to learn speech, overlooking the critical importance of language acquisition during sensitive developmental periods. Since the unbiased attitude of the professional community is influenced by knowledge, enhancing this knowledge base is expected to lead to more effective outcomes regarding the preservation of the golden window for language learning among deaf children.

Background and Aim: Given that the loudness obtained through the conventional methods cannot accurately represent the loudness of tinnitus due to the phenomenon of recruitment, and that the self-reported loudness is more reflective of tinnitus-related distress, and considering that previous studies have not demonstrated a significant correlation between tinnitus loudness and specific brain regions, the present study may provide a more appropriate method for evaluating tinnitus loudness and reveal stronger associations between loudness and brain areas. In this study, we addressed the relationship between tinnitus loudness estimates  and resting-state electroencephalography (EEG) activity in tinnitus-associated brain networks.
Methods: In this cross-sectional correlational study, twenty-one subjects with normal to moderate high-frequency hearing loss and tinnitus underwent psychoacoustic assessments including the Visual Analog Scales for Loudness (VAS-L), pitch matching, and loudness matching in both dB SL and phon units. Subsequently, EEG was recorded from all participants. The collected data were analyzed using statistical methods to examine the correlation between study variables and brain networks.
Results: Loudness in the phon was inversely related to delta band power and theta/alpha ratio in the frontal and central regions, but loudness in dB SL was positively correlated with delta band power in the right frontal region. Furthermore, self-reported loudness on the VAS was negatively correlated with theta-band power in the temporal and central regions.
Conclusion: These results emphasize the multifactorial nature of tinnitus perception and suggest that phon may be a more sensitive measure of tinnitus loudness.

Background and aim: The brain's ability to resolve rapid temporal cues such as voice-onset time (VOT) is essential for speech perception in challenging listening environments. We tested whether central auditory compensation for VOT in noise is reflected in the fidelity of cortical auditory evoked potentials (CAEPs) using a neural-network classifier and a cross-condition similarity metric.
Methods: Electroencephalography (EEG) was recorded from 22 normal-hearing adults in response to /ka/ and /ga/ syllables with varying VOTs, presented in quiet and noise (+7 dB Signal-to-noise ratio). We measured CAEPs’ peak amplitude (N1-P2), employed a convolutional neural network (CNN) to classify CAEPs by syllable identity, and computed a cross-condition correlation (r_cc) to quantify the similarity between responses in quiet and noise.
Results: Background noise significantly reduced N1-P2 amplitude, behavioral performance, and CNN classification accuracy, confirming the degradation of phoneme-specific neural representations. Critically, inter-subject variability in behavioral speech in noise performance was significantly correlated by both r_cc (r=0.443, p=0.02*) and CNN accuracy in noise (r=0.492, p=0.01*). Individuals with higher behavioral speech-in-noise (SIN) scores exhibited CAEPs in noise that were more similar to their clean-speech responses (higher r_cc) and more discriminable by CNN. Scalp topography displayed the highest r_cc values over fronto-central regions, with the strongest correlation between r_cc and SIN performance.
Conclusion: The convergence of our findings demonstrates that successful SIN perception relies on the brain's capacity to maintain a stable, noise-invariant cortical representation of speech, particularly in fronto-central auditory regions. These EEG-derived metrics may serve as a research tool for future clinical investigations.

Background and Aim: Cochlear implants (CI) offer significant benefits in speech-language and auditory development for children with severe to profound sensorineural hearing loss. However, in countries like India, barriers to accessing CI surgery persist, influenced by  factors including financial constraints and societal perceptions.. Therefore, the study aimed to investigate barriers and facilitators to CI uptake  in Karnataka.
Methods: A cross-sectional questionnaire-based study was conducted among parents of children who underwent cochlear implantation (CI group, n=82) and those who did not (non-CI group, n=102),  in Karnataka, India (n = 184). The questionnaire was developed through expert focus group discussion, literature review, and pilot testing, and included  sections on facilitators and barriers to CI uptake. Content validity was established using expert ratings (CVR and CVI), and demographic variables included parental education and socioeconomic status.
Results: The logistic regression model was significant [χ²(4) = 71.25, p < 0.001]. Higher parental education (aOR = 0.56, p < 0.001) and earlier age at recommendation (<3 years; aOR = 0.26, p = 0.001) were significant predictors of CI uptake, while income and gender were not (p > 0.05). Key barriers were financial burden, concerns about surgical complications, family opposition, caregiving responsibilities, and pandemic-related disruptions.
Conclusion: Facilitating CI uptake requires  financial support, tailored counselling, and early detection initiatives. Government initiatives should be supplemented with subsidized  CI spare parts.  . Addressing parental concerns and increasing awareness among healthcare professionals and policymakers are crucial to improve accessibility and  outcomes for children with hearing loss.

Background and Aim: Speech Sound Disorders (SSD) are associated with deficits in phonological awareness and reduced speech intelligibility. This study aimed to investigate the effectiveness of multisensory approach in enhancing phonological awareness, speech intelligibility, and the percentage of correct consonants in children with SSD.
Methods: A single-subject design was employed, structured into three phases. The study included three children aged 5 to 5.11 years with SSD who received intervention using the FONEMZ approach. Data analysis was conducted using visual analysis, Percentage of Non-overlapping Data (PND), Improvement Rate Difference (IRD), and the two-standard deviation (2SD) test.
Results: The multisensory approach effectively improved phonological awareness, speech intelligibility, and the percentage of correct consonants in children with SSD.
Conclusion: The findings highlight the significance of multisensory and interactive methodologies, particularly individualized therapy sessions, in facilitating phoneme acquisition and enhancing speech performance in children.
Trial Registration Number: The study was registered in the Iranian Registry of Clinical Trials on 4 November 2024 (IRCT20230403057804N4).

Background and Aim: Age-Related Hearing Loss (ARHL) impairs speech understanding in noise. Acceptable Noise Level (ANL) reflects noise tolerance and predicts hearing-aid outcomes, while Speech-in-Noise (SIN) ability is indexed by Signal-to-Noise Ratio required for 50% correct recognition (SNR-50). Their relationship under binaural listening remains unclear. This study examined binaural ANL and SIN performance in young normal-hearing and older hearing-impaired adults to determine their association and identify audiometric predictors.
Methods: Sixty-nine adults participated: 37 young normal-hearing (18–30 years) and 32 older adults with ARHL (60–80 years). Binaural ANL was measured using Persian continuous discourse with 12-talker babble. SIN performance was assessed binaurally using a monosyllabic word test, with SNR-50 estimated by the Spearman-Kärber method. Group comparisons, correlations, and regression analyses examined age effects and audiometric predictors.
Results: Older adults showed higher most comfortable levels and ANL values, indicating reduced noise tolerance, and poorer SIN performance with higher SNR-50 and greater variability. Binaural ANL was not associated with SNR-50 in either group. In older adults, SIN performance was predicted by high-frequency thresholds and hearing loss severity, whereas ANL was not a significant predictor.
Conclusion: Under binaural conditions, noise tolerance and speech intelligibility are dissociable. In older adults, SIN ability was predicted by high-frequency hearing sensitivity and overall hearing loss severity, whereas ANL was not a significant predictor, underscoring the importance of multidimensional auditory assessment in clinical practice.

Background and Aim: Chronic pain remains a major clinical challenge, with many patients experiencing insufficient relief from conventional therapies. Emerging evidence suggests functional overlap between vestibular networks and central pain-processing systems. This narrative review aimed to evaluate the potential of vestibular stimulation to modulate nociceptive processing and influence pain perception. Relevant literature was identified through PubMed, Scopus, and Web of Science searches, and studies addressing vestibular–pain interactions were narratively reviewed.
Recent Findings: Clinical observations indicate that cold caloric vestibular stimulation may transiently alleviate various forms of central and neuropathic pain, including central post-stroke pain, phantom limb pain, spinal cord injury–related pain, and complex regional pain syndrome. Small randomized and quasi-experimental trials provide partial support for these findings, although reported effects are generally short-lived and heterogeneous across studies. Laboratory-based psychophysical experiments further suggest that vestibular input can alter pain thresholds and sensory integration processes. Functional neuroimaging studies implicate vestibulo–thalamo–insular and vestibulo–limbic circuits, highlighting shared neural pathways involved in both vestibular and nociceptive processing. Collectively, the evidence suggests that vestibular stimulation may influence both the sensory-discriminative and affective-motivational dimensions of pain.
Conclusion: Vestibular stimulation may represent a promising non-invasive approach for modulating pain perception through central multisensory integration mechanisms. Current evidence suggests potential analgesic effects; however, findings remain heterogeneous and the durability of these effects is not yet well established. Further large, well-designed randomized controlled trials are needed to determine clinical efficacy, optimal stimulation parameters, and long-term outcomes before routine clinical implementation can be considered.

Background and Aim: The Subjective Visual Vertical (SVV) is a reliable clinical measure of an individual's ability to determine whether an object is oriented in the vertical plane, regardless of the presence of a true vertical reference. The study aimed to examine the influence of various background conditions on SVV deviation and response time, compare these outcomes between healthy younger and middle-aged adults and to measure the test-retest reliability of the SVV paradigm.
Methods: The SVV test was performed in healthy younger and middle-aged adults. A total of 100 participants were recruited for the study, 50 per group. The SVV test was administered using a standardized videonystagmography instrument (Cyclops Balance-eye device) in static and dynamic (clockwise and counterclockwise) visual background Conditions. The outcome variables, SVV deviation (°) and response time (s), were recorded under each condition. Test-retest reliability was also measured.
Results: Significant differences in SVV deviation and response time were observed across the testing conditions. Between-group analysis showed significantly greater SVV deviation under the counterclockwise and static background conditions in middle-aged adults compared with younger adults, whereas response time differed significantly between the groups under the clockwise and counterclockwise conditions. The SVV paradigm demonstrated good test–retest reliability.
Conclusion: Dynamic SVV conditions were more sensitive than static conditions in detecting differences in SVV deviation and response time between younger and middle-aged adults, indicating subtle age-related changes in visual–vestibular processing. The SVV paradigm also demonstrated good test–retest reliability, supporting its clinical applicability.

Background and Aim: Falls in older adults are a major clinical and public health issue, often linked to dizziness and vestibular dysfunction. Changes in verticality perception, visual dependence, and postural control can increase fall risk. This study compared vestibular–perceptual and and postural control characteristics using a virtual reality system between older adults with and without dizziness-related falls.
Methods: We enrolled 66 older adults in a fall group (n = 33) or a control group (n = 33) based on dizziness-related falls. All participants met the same criteria for cognitive status, sensory function, psychological health, medical stability, and vestibular integrity. We assessed static and dynamic subjective visual vertical (SVV) and used a virtual reality reaching task to measure postural control. Participants also completed self-reported dizziness-related disability and fear of falling measures. We compared groups and ran regression analyses, controlling for age.
Results: Compared to controls, older adults with falls showed greater deviations in static and dynamic SVV and higher visual dependence (p < 0.05). The fall group also had reduced center-of-pressure displacement and trunk excursion during the virtual reaching task. Dizziness-related disability and fear of falling correlated with vestibular–perceptual and postural measures.
Conclusion: Older adults who experience dizziness-related falls exhibit impaired verticality perception, greater reliance on visual cues, and altered postural control. These findings underscore the value of vestibular–perceptual assessments and virtual reality tasks for identifying fall risk and guiding targeted rehabilitation for older adults.

Background and aim: Bilingualism is linked to modifications in neural pathways that influence auditory processing. Auditory evoked potentials, including auditory late responses (ALRs), are cortical waves generated in response to sound, which provide insights into auditory processing. This study investigated the relationship between simultaneous bilingualism and binaural processing by examining the binaural interaction component (BIC) of ALRs.
Methods: This cross-sectional study included fifty-six participants, aged 19 to 30 years, classified into monolingual (Persian) and simultaneous bilingual (Turkish-Persian) groups (MG and BG). ALRs were recorded during both monoaural and binaural stimulation. P1, N1, and P2 latencies, as well as P1-N1 and N1-P2 inter-peak amplitudes, were recorded. The BIC was calculated by subtracting the binaural response waveform from the sum of the summed monaural response waveforms.
Results: In binaural stimulation and for the BIC values, BG exhibited shorter mean latencies for all ALR components compared to the MG. This latency reduction reached statistical significance for the P2 component during binaural stimulation and for the N1 and P2 components in the BIC (p<0.05). Mean inter-peak amplitudes showed variability between groups, with the MG demonstrating a significantly greater P1-N1 component amplitude in the BIC (p<0.05).
Conclusion: The reduction in latency and BIC amplitude of the ALR components in simultaneous bilinguals suggests possible changes in the auditory cortical processing. Meanwhile, the variability of BIC amplitude highlights the need for caution in interpreting this component. Also, all analyses were performed without correction for multiple comparisons. Therefore, these exploratory findings require confirmation in future studies.

Background and Aim: Toxic encephalitis, a rare form of neuroinflammation induced by toxic agents, can lead to multifaceted neurological dysfunction, including auditory impairment. Sensorineural hearing loss (SNHL), a reduction in hearing sensitivity due to inner ear or auditory nerve damage, is an uncommon but clinically significant manifestation in such cases. This study aimed to present a comprehensive audiological and neurological evaluation of a patient with toxic encephalitis to highlight the auditory consequences and emphasize the importance of early detection and intervention.
Case presentation: We report a 44-year-old woman with progressive bilateral SNHL over one year and vertigo. Neurological examination showed cerebellar dysfunction, and Magnetic resonance imaging revealed multiple acute infarcts with basal meningeal enhancement and vasculitic changes suggestive of toxin-induced neuroinflammatory injury. Occupational history confirmed prolonged exposure to industrial solvents, a recognized neurotoxic factor. Audiological testing demonstrated bilateral moderate SNHL with absent otoacoustic emissions and abnormal auditory brainstem responses, supporting the diagnosis of toxic encephalopathy with encephalitic features.
Conclusion: This study highlights the significant impact of toxic encephalitis on auditory pathways, revealing vulnerabilities in cochlear and brainstem structures. By integrating behavioral, physiological, and electrophysiological evaluations, it provides insights into hearing loss associated with the condition. Early diagnosis and intervention are crucial to improving outcomes, and further research is needed to explore the mechanisms linking toxic encephalitis features and auditory dysfunction.

Background: Persistent Postural-Perceptual Dizziness (PPPD) is a chronic functional vestibular disorder characterized by persistent non-spinning dizziness aggravated by motion, upright posture, and visually complex environments. Multimodal management including vestibular rehabilitation therapy (VRT) and cognitive behavioral therapy (CBT) is recommended; however, evidence supporting cognition-integrated tele-vestibular rehabilitation remains limited. This case aimed to examine the clinical utility of a CBT-informed tele-vestibular rehabilitation model in PPPD secondary to peripheral vestibular dysfunction.
The Case: A 31-year-old female presented with a two-year history of persistent dizziness, episodic vertigo, motion sensitivity, and visual dependence, along with anxiety and depressive symptoms. Audiological findings were normal. Vestibular evaluation revealed spontaneous left-beating nystagmus, right-sided utricular involvement on oVEMP (prolonged latencies, reduced amplitudes), and corrective saccades in the right lateral canal on vHIT; MRI findings were unremarkable. Baseline scores indicated severe handicap (DHI: 76/100) and high functional limitation (VADL; Niigata PPPD Questionnaire: 83/114). The patient underwent a 10-month structured program comprising four months of tele-VRT followed by six months of cognition-integrated tele-rehabilitation incorporating psychoeducation, self-monitoring, cognitive restructuring, and graded exposure. Post-intervention outcomes demonstrated reduced symptom severity (NPQ: 45/114), improved VADL scores, decreased DHI (53/100), increased right oVEMP amplitudes, and resolution of corrective saccades on vHIT.
Conclusion: Cognition-integrated tele-vestibular rehabilitation was associated with meaningful functional, psychological, and partial objective vestibular improvements. This case highlights the feasibility and potential benefit of remotely delivered, multidimensional rehabilitation in PPPD and underscores the need for larger controlled studies.

Background: Spontaneous intracranial hypotension is a recognized clinical entity caused by spinal cerebrospinal fluid leakage and is classically characterized by orthostatic headache. However, some patients initially present with audiovestibular symptoms that may mimic primary inner ear disorders and lead to diagnostic delay. Recognition of this atypical presentation is essential to avoid misdiagnosis and to facilitate timely neuroimaging and appropriate management.
The Cases: Two patients with spontaneous intracranial hypotension are described, in whom tinnitus, sound sensitivity, aural fullness, and dizziness constituted the predominant initial manifestations. A cerebrospinal fluid–venous fistula at the level of the tenth thoracic vertebra was identified using computed tomography myelography, and symptoms resolved following transvenous embolization after unsuccessful epidural blood patch therapy. In another patient, no definite site of cerebrospinal fluid leakage could be localized, and conservative management was preferred. A review of the literature is also provided, focusing on the proposed pathophysiological relationship between reduced cerebrospinal fluid pressure and secondary endolymphatic hydrops.
Conclusion: Spontaneous intracranial hypotension should be considered in the differential diagnosis of patients presenting with hydrops-like audiovestibular symptoms, even in the absence of headache. Early recognition and appropriate neuroimaging are essential for accurate diagnosis and optimal management.