Auditory and Vestibular Research

Temporal Processing Abilities in Children with Repaired Cleft Lip and Palate: A Systematic Review

Pushpavathi Mariswamy — 2026-03-19

Background and Aim: Children with Repaired Cleft Lip and Palate (RCLP) are at increased risk for auditory processing difficulties, particularly in speech perception in noise and temporal auditory processing. Although emerging evidence suggests deficits in central auditory processing in this population, a systematic synthesis of temporal processing abilities remains limited. This review aimed to critically evaluate and synthesize existing evidence on temporal auditory processing abilities in children with RCLP.
Recent Findings: A systematic literature search was conducted independently by two reviewers across PubMed, Scopus, CINAHL, ScienceDirect, and ProQuest for studies published between January 2000 and March 2025. Study selection was performed through title, abstract, and full-text screening. Eligibility criteria were defined using the PICOS framework, and risk of bias was assessed for all included studies. Of 1,132 identified records, 12 studies met the inclusion criteria. The reviewed evidence consistently demonstrated auditory processing deficits in children with RCLP, with temporal processing identified as the most frequently and severely affected domain. Across studies, children with RCLP showed significantly poorer temporal processing performance compared to craniofacially typical peers.
Conclusion: This review underscores the clinical relevance of temporal auditory processing deficits in children with repaired cleft lip and palate. Unrecognized temporal processing impairments may adversely affect academic performance, reading skills, and speech–language development. Incorporating temporal auditory processing assessment into routine audiological evaluations is therefore recommended for early identification and targeted intervention. Future research should further investigate other subtypes of auditory processing disorders in this population to enhance clinical management strategies.

Eyes Closed vs. Eyes Open: Investigating Brain Activity Differences in Tinnitus Patients Using Multi-Channel Electroencephalography-A Preliminary Study

Sahand Nazeri — 2025-08-30

Background and Aim: Tinnitus, the perception of sound without an external source, significantly affects the quality of life for millions worldwide. Although many studies have explored its pathophysiology and neural underpinnings using various methods during resting states, the influence of eye state on neural activity remains poorly understood. This study examined brain activity differences between eyes-closed and eyes-open resting states in individuals with chronic tinnitus.
Methods: In this cross-sectional study, twenty patients with chronic tinnitus underwent Electroencephalography (EEG) during both eyes-closed and eyes-open resting states. EEG power spectra, source localization, and functional connectivity were analyzed across eight frequency bands. Paired-sample t-test and Statistical non-Parametric Mapping (SnPM) test compared neural activity between these conditions.
Results: Eyes-closed recordings showed decreased delta, theta, and gamma power, increased alpha 1 and alpha 2 power, and a complex beta pattern (increased beta 1, decreased beta 2 and beta 3) compared to eyes-open. Source localization analysis revealed greater activity in regions associated with memory, attention, and emotional processing during eyes-closed compared to eyes-open. Functional connectivity analysis indicated stronger connections between auditory and memory-related regions in eyes-closed compared to eyes-open.
Conclusion: This preliminary study demonstrated distinct EEG power spectra, source localization, and functional connectivity between eyes-closed and eyes-open states in chronic tinnitus patients, suggesting state-specific neural patterns. Findings highlight interactions of sensory, cognitive, and affective processes, potentially relevant to tinnitus. Further research with control groups and larger samples is needed to confirm tinnitus-specific effects and optimize EEG conditions for elucidating neural mechanisms and guiding targeted interventions.

Impact of Anodal Transcranial Direct Current Stimulation on Listening Effort, Mental Fatigue, Tinnitus Annoyance, Working Memory, and Expression of NMDA Receptor Subunits in Adults with Tinnitus

Azadeh Imani — 2025-09-17

Background and Aim: Tinnitus is associated with increased listening effort and reduced Working Memory (WM) during speech comprehension. A practical approach to enhance cognitive processes is transcranial Direct Current Stimulation (tDCS). This study aimed to evaluate the effect of tDCS on listening effort, mental fatigue, tinnitus annoyance, WM, and expression of N-Methyl-D-Aspartate (NMDA) receptor subunits (NR1 and NR2) in the blood of individuals with tinnitus.
Methods: Thirty-two chronic tinnitus participants (aged 30–60 years) were randomly assigned to intervention and control groups. The intervention group received anodal tDCS over the left Dorsolateral Prefrontal Cortex (DLPFC) with electrode on F3 for 20 minutes at 1.5 mA over 10 sessions, while the control group underwent sham tDCS. Pre- and postintervention assessments included audiometry, tympanometry, tinnitus matching, a dualtask paradigm for measuring listening effort, the visual analogue scale for measuring mental fatigue, the Tinnitus Functional Index (TFI) for measuring tinnitus annoyance, and the N-Back test for WM assessment. Western blot analysis of blood samples measured NR1 and NR2 protein expression.
Results: Compared to the control group, active tDCS significantly reduced listening effort, mental fatigue, tinnitus annoyance (p<0.001) and improved WM (p<0.001). After intervention, the intervention group showed a 27% increase in NR1 and a 50% increase in NR2 expression.
Conclusion: The tDCS over DLPFC can reduce listening effort, mental fatigue, and tinnitus annoyance, and enhance WM in adults with chronic tinnitus, which is associated with improved NR1/NR2 protein expression in blood. These findings highlight the potential role of tDCS in tinnitus rehabilitation.

Enhancing Auditory Spatial Perception through Music: Interplay between Musical Aptitude and Training

Sushmitha Upadhya — 2025-09-23

Background and Aim: Musicians can detect changes in minute aspects including pitch, timing, and loudness, all of which assist in auditory spatial perception. This study hypothesized that non-musicians with musical aptitude might display spatial skills comparable to trained musicians, and superior to non-musicians without musical aptitude.
Methods: To test this hypothesis, we considered 101 participants in three groups: musicians (n=33, trained in classical music), 33 Non-Musicians with Good musical Aptitude (NMGA) and 35 Non-Musicians with Poor musical Aptitude (NM-PA), selected based on convenience sampling. Music aptitude was assessed using the Mini profile of music perception skills. A spatial test battery consisting of tests of binaural interaction Interaural Time Difference (ITD) and Interaural Level Difference (ILD), and Virtual Acoustic Space Identification (VASI) test were administered.
Results: Musicians and NM-GA demonstrated significantly lower ITD and ILD thresholds than NM-PA, suggesting the role of musical aptitude in sound lateralization. In VASI test, musicians scored highest, followed by NM-GA, who in turn had significantly higher scores than NM-PA, suggestive of further refinement of innate musical advantage due to training in musicians. Location specific analysis revealed NM-PA made significantly greater errors in right 45, left 45, right 135, and left 135 (p<0.001), often confusing them with extreme right (R 90) or left (L 90) locations.
Conclusion: Both innate musical aptitude and formal musical training contribute to enhanced spatial hearing abilities. While musicians and NM-GA exhibit superior ITD and ILD thresholds, musicians outperform NM-GA in VASI scores, indicating training refines complex spatial perception beyond natural aptitude.

Preliminary Report on the Efficacy of the Dichotic Offset Training Program in Auditory Integration Processing Disorder: A Single-Subject Study

Saeidreza Babaei Ashkezari — 2025-09-28

Background and Aim: Auditory integration deficit is a complex typs of Auditory Processing Disorder (APD). This is due to its association with specific brain regions such as the corpus callosum and angular gyrus, which are key areas for multisensory integration. This study introduced the first Persian development of the dichotic offset training program. It presents preliminary findings on its efficacy when delivered in-person versus on-line.
Methods: In this single-subject study, two children, aged 13 years, diagnosed with auditory integration deficit, participated. The main intervention consisted of 8–14 sessions of PersianDichotic Offset Training (P-DOT), followed by post-treatment follow-up assessments utilizing two methods of treatment delivery: in-person and on-line. Data collected via Persian-Buffalo Model Questionnaire-Revised (P-BMQ-R), Persian Randomized Dichotic Digits Test (P-RDDT), Persian-Dichotic Offset Test (P-DOT), and Persian-Staggered Spondee Word (P-SSW) and analyzed employing a single-subject statistical formula.
Results: The results suggest that the treatment effectively reduced integration problems in both in-person and on-line methods, as indicated by competitive left ear stimulus, Type A pattern, and qualitative error IX, the left ear performance, and the questionnaire scores. Both delivery methods proved effective, but online administration showed slightly superior outcomes.
Conclusion: The P-DOT Program, especially in its on-line method, appears to be a promising intervention for children with APD (integration subcategory). By enhancing binaural hearing skills, this approach may considerably improve the brain regions responsible for dichotic processing. These preliminary single-subject findings, pending confirmation through larger-scale studies, particularly Randomized Controlled Trial (RCT) studies, may inform evidence-based clinical protocols for audiologists.

Cervical and Ocular Vestibular Evoked Myogenic Potentials in Children with Speech Sound Disorder

Prajeesh Thomas — 2025-10-11

Background and Aim: Speech Sound Disorder (SSD) is a developmental communication disorder characterised by children’s difficulties in producing speech sounds clearly. Auditory deficits, sensory integration issues and motor execution difficulties are reported in children with SSD. The vestibular system, being in proximity to the auditory system and important in sensory integration, requires exploration of its function in children with SSD. The study compared latency and amplitude parameters of Vestibular Evoked Myogenic Potentials (VEMPs) in children with SSD and typically developing children to assess otolithic function.
Methods: The study employed a standard group comparison, involving 10 children with SSD and 10 typically developing children matched for age and gender in the 6–11 years age range (7 boys). Participants underwent cervical VEMP and ocular VEMP testing in a sound-treated room, with appropriate strategies in place to ensure their cooperation with the test procedures.
Results: Statistically significantly higher peak-to-peak amplitude for cVEMP and oVEMP was observed in typically developing children, whereas the amplitude asymmetry ratio was statistically higher in children with SSD. Both findings suggest possible alterations in vestibular function among children with SSD, a finding reported for the first time in the literature.
Conclusion: Alterations in sacculo-collic and utriculo-ocular pathway function might be concomitant in children with SSD. This may influence sensory information related to relative position, movement of articulators, as well as the muscle tone of the neck and head, including articulators. The findings pave the way for exploring adjunct vestibular rehabilitation with speech-language intervention in children with SSD.

Different Effects of Temporal and Spectral Regularities on Auditory Stream Segregation

Sanaz Soltanparast — 2025-10-11

Background and Aim: The fact that recognizing sound regularities plays a crucial role in segregating auditory streams has recently garnered significant interest. This study aimed to investigate how temporal and spectral regularities incorporated into the background auditory stream affect auditory stream segregation.
Methods: Twenty-five healthy young adults performed an indirect measure of the auditory streaming task (i.e. detecting rare-level targets). They were presented with two concurrent auditory streams involving foreground and background streams, and were asked to detect rare-level targets in the foreground stream during three experimental conditions (spectral, temporal, or random regularities).
Results: Temporal and spectral regularities of the background auditory stream significantly increased the hit rate compared to random regularities. This effect of regular cues on target detection and possibly stream segregation was significantly greater under temporal regularity conditions than under spectral regularity conditions.
Conclusion: The findings suggest that incorporating temporal or spectral regularities into the background auditory stream can facilitate target detection and possibly stream segregation. This perceptual regularity benefit is greater for temporal regularities than for spectral regularities. These findings may provide primary evidence for the distinct facilitating effects of various theoretical frameworks on sound feature regularities and auditory streaming.

Clinical Utility of the Tamil Speech-in-Noise Test for Detecting Hidden Hearing Loss in Tinnitus with Normal Audiograms: Insights from Behavioral and Electrophysiological Measures

Arun Kumar — 2025-10-11

Background and Aim: Tinnitus often occurs in individuals with normal audiograms and may reflect Hidden Hearing Loss (HHL). Conventional audiometry fails to detect these suprathreshold deficits. This study evaluated the clinical utility of a validated Tamil Speechin-Noise (SIN) test, supported by Otoacoustic Emissions (OAEs) and Auditory Brainstem Responses (ABRs), in detecting HHL in tinnitus patients.
Methods: Thirty native Tamil-speaking adults were recruited: 15 with chronic bilateral tinnitus and 15 matched controls. All had normal hearing thresholds. Participants underwent the Tamil Speech-in-Noise (SIN) test, Transient Evoked Otoacoustic Emissions (TEOAEs), Distortion Product Otoacoustic Emissions (DPOAEs), and click-evoked Auditory Brainstem Response (ABR). Group differences were analyzed using independent-sample t-tests.
Results: The tinnitus group showed significantly higher Signal-to-Noise Retios at 50% correct (SNR-50) values and Signal-to-Noise Ratio (SNR) loss compared to controls, indicating impaired SIN perception. Both DPOAEs and TEOAEs were significantly reduced across frequencies, confirming cochlear dysfunction despite normal audiograms. ABR analysis revealed delayed wave I and wave III latencies, with marginal prolongation of wave V, indicating early auditory nerve involvement.
Conclusion: Tinnitus patients with normal audiograms demonstrate measurable auditory deficits, reflecting HHL. The Tamil SIN test, complemented by both OAE and ABR, provides a culturally appropriate and sensitive protocol for early detection. These findings highlight the limitations of pure-tone audiometry and support integrating multimodal assessments into tinnitus evaluations.

Prevalence and Factors Associated with Benign Paroxysmal Positional Vertigo and Falls in Hajj: A Cross-Sectional Study

Hanin Rayes — 2025-10-12

Background and Aim: Benign Paroxysmal Positional Vertigo (BPPV) is a common vestibular disorder, typically affecting older adults, and is a recognized cause of vertigo and falls. The physically demanding conditions of Hajj may increase dizziness and fall risk, yet BPPV has not been studied in this mass-gathering context. This study aimed to estimate the self-reported prevalence of BPPV and falls among Hajj pilgrims, and to explore selfreported triggers of dizziness.
Methods: A cross-sectional survey was conducted during Hajj 2022–2023 using a validated Arabic questionnaire adapted from published BPPV screeners. Diagnosis of probable BPPV was based solely on self-reported responses to two screening items (brief vertigo episodes <1 minute provoked by specific positional changes). The questionnaire also assessed demographics, comorbidities, falls, and self-reported triggers of dizziness during religious activities.
Results: Of 183 respondents, 144 were eligible for analysis (mean age=36.8 years; range=16–72). Overall, 22.2% (95% CI: 15.7%–29.9%), reported dizziness, but only 1.4% (95% CI: 0.2%–4.9%) met the self-reported criteria for probable BPPV. The incidence of falls during Hajj was 2.1% (95% CI: 0.4%–6.0%), with no significant association with BPPV. Bowing during prayer was the only religious activity significantly associated with BPPV, although this was based on just two BPPV-positive cases.
Conclusion: The prevalence of BPPV was low in this predominantly young sample, limiting generalizability to the wider pilgrim population, which usually includes many older adults. Findings highlight the need for age-diverse, clinically confirmed studies to better understand vestibular health risks during Hajj.

Reliability and Validity of the Persian Version of the 12-Item Tinnitus Primary Function Questionnaire

Alireza Ranjbar — 2025-10-12

Background and Aim: Tinnitus creates socioeconomic challenges. Questionnaires are widely used to assess their impact on daily life. This study aimed to validate the Persian version of the 12-item Tinnitus Primary Function Questionnaire (P-TPFQ) to provide a culturally appropriate tool for evaluating tinnitus-related disability in Persian speakers.
Methods: This study with a cross-sectional design was conducted on 56 adults experiencing tinnitus. The TPFQ was translated according to the international quality of life assessment protocol. Content validity and face validity was evaluated using the Content Validity Ratio (CVR), Content Validity Index (CVI) and the Face Validity Index (FVI). Internal consistency was determined using Cronbach’s alpha. Convergent validity was tested by assessing the correlation with the scores of the Tinnitus Handicap Inventory (THI), Beck Depression Inventory-II (BDI-II), and Pittsburgh Sleep Quality Index (PSQI). Test-retest reliability was assessed using the Intraclass Correlation Coefficients (ICC). Confirmatory Factor Analysis (CFA) examined the construct validity.
Results: Content and face validity were excellent (CVR=1.0, CVI=1.0, FVI=1.0). The CFA confirmed a four-factor structure with high loadings (0.85–0.97). Internal consistency was high (Cronbach’s α=0.956 for the overall scale; 0.922–0.969 for the subscales). The total P-TPFQ score had a strong and significant correlation with the THI score (r=0.845), and a moderate and significant correlation with BDI-II (r=0.600) and PSQI (r=0.416) scores (p<0.001). Test–retest reliability was high (ICC=0.956).
Conclusion: The P-TPFQ with 12 items and four subscales has excellent reliability and validity. As a multidimensional tool, it can be used for assessing tinnitus-related behavioural aspects.