Objectives: . The present study aimed to determine the effect of music-based auditory training on older adults with hearing loss and decreased cognitive ability, which are common conditions in the older population. Methods: . In total, 20 older adults diagnosed with both mild-to-moderately severe hearing loss and mild cognitive impairment (MCI) participated. Half of this group were randomly assigned to the auditory training group (ATG), and the other half were designated as the control group (CG). For the ATG, a 40-minute training session (10 minutes for singing a song, 15 minutes for playing instruments, and 15 minutes for playing games with music discrimination) was conducted twice a week for 8 weeks (for a total of 16 sessions). To confirm the training effects, all participants were given tests pre- and post-training, and then a follow-up test was administered 2 weeks after the training, using various auditory and cognitive tests and a self-reporting questionnaire. Results: . The ATG demonstrated significant improvement in all auditory test scores compared to the CG. Additionally, there was a notable enhancement in cognitive test scores post-training, except for the digit span tests. However, there was no statistically significant difference in the questionnaire scores between the two groups, although the ATG did score higher post-training. Conclusion . The music-based auditory training resulted in a significant improvement in auditory function and a partial enhancement in cognitive ability among elderly patients with hearing loss and MCI. We anticipate that this music-based approach will be adopted for auditory training in clinical settings due to its engaging and easy-to-follow nature.

Background and Objectives: The digits-in-noise (DIN) test was developed as a simple and time-efficient hearing-in-noise test worldwide. The Korean version of the DIN (K-DIN) test was previously validated for both normal-hearing and hearing-impaired listeners. This study aimed to explore the factors influencing the outcomes of the K-DIN test further by analyzing the threshold (representing detection ability) and slope (representing test difficulty) parameters for the psychometric curve fit. Subjects and Methods: In total, 35 young adults with normal hearing participated in the K-DIN test under the following four experimental conditions: 1) background noise (digit-shaped vs. pink noise); 2) gender of the speaker (male vs. female); 3) ear side (right vs. left); and 4) digit presentation levels (55, 65, 75, and 85 dB). The digits were presented using the method of constant stimuli procedure. Participant responses to the stimulus trials were used to fit a psychometric function, and the threshold and slope parameters were estimated according to pre-determined criteria. The accuracy of fit performance was determined using the root-mean-square error calculation. Results: The listener’s digit detection ability (threshold) was slightly better with pink noise than with digit-shaped noise, with similar test difficulties (slopes) across the digits. Gender and the tested ear side influenced neither the detection ability nor the task difficulty. Additionally, lower presentation levels (55 and 65 dB) elicited better thresholds than the higher presentation levels (75 and 85 dB); however, the test difficulty varied slightly across the presentation levels. Conclusions The K-DIN test can be influenced by stimulus factors. Continued research is warranted to understand the accuracy and reliability of the test better, especially for its use as a promising clinical measure.

Background and Objectives: The present study aimed to explore meaningful change in the musical performance of cochlear implant (CI) users according to age after receiving music training compared to the other CI users who did not receive any music training and normal hearing (NH) listeners. Materials and Methods: Article search was conducted from five journal databases. In accordance with PICOS criteria, 29 articles and 15 articles were included for the CI and NH groups, respectively. A total of 44 articles consisting of 407 CI users and 486 NH participants were then analyzed. Using the data gathered from pre- and post-training, meta-analysis was applied by the random-effects model, and then piecewise meta-regression was employed. Results: CI users with music training showed better performance than those without the training across all ages. The curve change in musical performance when training showed that the CI users was similar to the general pattern of NH performance, indicating that the CI users gained benefits from music training and developed perceptual ability, even though it was not as high as the level of NH counterparts. Conclusions This finding supports the benefits of active engagement with music for both CI users and NH listeners, while noting the important role of music as one of the primary aural rehabilitation approaches.

Background and Objectives: Although the digit-in-noise (DIN) test is simple and quick, little is known about its key factors. This study explored the considerable components of the DIN test through a systematic review and meta-analysis. Materials and Methods: After six electronic journal databases were screened, 14 studies were selected. For the meta-analysis, standardized mean difference was used to calculate effect sizes and 95% confidence intervals. Results: The overall result of the meta-analysis showed an effect size of 2.224. In a subgroup analysis, the patient’s hearing status was found to have the highest effect size, meaning that the DIN test was significantly sensitive to screen for hearing loss. In terms of the length of the presenting digits, triple digits had lower speech recognition thresholds (SRTs) than single or pairs of digits. Among the types of background noise, speech-spectrum noise provided lower SRTs than multi-talker babbling. Regarding language variance, the DIN test showed better performance in the patient’s native language(s) than in other languages. Conclusions When uniformly developed and well validated, the DIN test can be a universal tool for hearing screening.

Background and Objectives: Natural and synthetic speech signals effectively stimulate cortical auditory evoked potential (CAEP). This study aimed to select the speech materials for CAEP and identify CAEP waveforms according to gender of speaker (GS) and gender of listener (GL). Subjects and Methods: Two experiments including a comparison of natural and synthetic stimuli and CAEP measurement were performed of 21 young announcers and 40 young adults. Plosive /g/ and /b/ and aspirated plosive /k/ and /p/ were combined to /a/. Six bisyllables–/ga/-/ka/, /ga/-/ba/, /ga/-/pa/, /ka/-/ba/, /ka/-/pa/, and /ba/-/pa/–were formulated as tentative forwarding and backwarding orders. In the natural and synthetic stimulation mode (SM) according to GS, /ka/ and /pa/ were selected through the first experiment used for CAEP measurement. Results: The correction rate differences were largest (74%) at /ka/-/ pa/ and /pa/-/ka/; thus, they were selected as stimulation materals for CAEP measurement. The SM showed shorter latency with P2 and N1-P2 with natural stimulation and N2 with synthetic stimulation. The P2 amplitude was larger with natural stimulation. The SD showed significantly larger amplitude for P2 and N1-P2 with /pa/. The GS showed shorter latency for P2, N2, and N1-P2 and larger amplitude for N2 with female speakers. The GL showed shorter latency for N2 and N1-P2 and larger amplitude for N2 with female listeners. Conclusions Although several variables showed significance for N2, P2, and N1-P2, P1 and N1 did not show any significance for any variables. N2 and P2 of CAEP seemed affected by endogenous factors.

Background and Objectives: Trendy technologies, such as artificial intelligence, virtual reality (VR), and augmented reality (AR) are being increasingly used for hearing loss, tinnitus, and vestibular disease. Thus, we conducted this systematic review and meta-analysis to identify the possible benefits of the use of VR and AR technologies in patients with hearing loss, tinnitus, and/or vestibular dysfunction, with the aim of suggesting potential applications of these technologies for both researchers and clinicians. Materials and Methods: Published articles from 1968 to 2022 were gathered from six electronic journal databases. Applying our specified inclusion and/or exclusion criteria, 23 studies were analyzed. As only one article on hearing loss and two articles on tinnitus were found, 20 studies on vestibular dysfunction were only finally included for the meta-analysis. Standardized mean differences (SMDs) were chosen as estimates to compare the studies. A funnel plot and Egger’s regression analysis were used to identify any risk of bias. Results: High heterogeneity (I2: 83%, τ2: 0.5431, p<0.01) was identified across the studies on vestibular dysfunction. VR-based rehabilitation was significantly effective for individuals with vestibular disease (SMDs: 0.03, 95% confidence interval [CI]: -0.08 to 0.15, p<0.05). A subgroup analysis revealed that only improvement in the subjective questionnaire was meaningful and statistically significant (SMDs: -0.66, 95% CI: -1.10 to -0.22). Conclusions VR-based vestibular rehabilitation showed potential for subjective rating measures like Dizziness Handicap Index. The negative effect of aging on vestibular disease was indirectly confirmed. More clinical trials and an evidence-based approach are needed to confirm the implementation of state-of-the-art technology for hearing loss and tinnitus, representative diseases in neurotology.

Background and Objectives: The purpose of the present study was to validate the performance and diagnostic efficacy of the Korean digits-in-noise (K-DIN) test in comparison to the Korean speech perception-in-noise (K-SPIN) test, which is the representative speech-in-noise test in clinical practice. Subjects and Methods: Twenty-seven subjects (15 normal-hearing and 12 hearing-impaired listeners) participated. The recorded Korean 0-9 digits were used to form quasirandom digit triplets; 50 target digit triplets were presented at the most comfortable level of each subject while presenting speech-shaped background noise at various levels of signal-to-noise ratios (-12.5, -10, -5, or +5 dB). Subjects were then instructed to listen to both target and noise masker unilaterally and bilaterally through a headphone. K-SPIN test was also conducted using the same procedure as the K-DIN. After calculating their percent correct responses, K-DIN and K-SPIN results were compared using a Pearson-correlation test. Results: Results showed a statistically significant correlation between K-DIN and K-SPIN in all hearing conditions (left: r=0.814, p<0.001; right: r=0.788, p<0.001; bilateral: r=0.727, p<0.001). Moreover, the K-DIN test achieved better testing efficacy, shorter average listening time (5 min vs. 30 min), and easier performance of task according to participants’ qualitative reports than the K-SPIN test. Conclusions In this study, the Korean version of digit triplet test was validated in both normal-hearing and hearing-impaired listeners. The findings suggest that the K-DIN test can be used as a simple and time-efficient hearing-in-noise test in audiology clinics in Korea.

Background and Objectives: This study aimed to investigate the occupational performance of Korean workers with and without hearing loss and analyze the hearing-related difficulties in the working environment. Subjects and Methods: The Amsterdam checklist for hearing and work was used for the analyses and the occupational environments of the Korean workers were investigated. Out of 129 total participants, 86 workers experienced severe to profound hearing loss and 43 had the normal hearing ability. The hearing-impaired workers were recruited from two leading vocational centers and normal-hearing workers were their colleagues. Results: The hearing-impaired workers were found to take fewer sick leaves and exhibited higher rates of permanent job statuses compared to the normal-hearing workers. Workers with hearing loss rarely detected background sound; however, they could perceive reverberation more frequently. They felt more satisfied with their careers than the normal hearing workers as they received social support and needed to put their effort into hearing for most hearing activities. Furthermore, the effort in hearing increased with the increase in job demand, job control, social support, and career satisfaction. The working hours per week increased with the increase in age, education level, job demand, job control, and social support. Different trends were observed in 9 out of 12 variables while comparing the data from the present study with that obtained from the hearing-impaired workers of the Netherlands, indicating a large difference between countries. Conclusions Although the hearing-impaired Korean workers operate diligently with good job positions, it is necessary to enhance their acoustic environment and provide them social support. Considering the cultural background of the hearing-impaired workers, the development of suitable vocational rehabilitation programs and specific questionnaires is strongly recommended worldwide.

It is acknowledged that there is a negative relationship between dementia and auditory function in older adults. This study conducted a systematic review and meta-analysis based on the data of audiologic testings from patients with neurodegenerative diseases in terms of auditory eventrelated potentials and central auditory processing tests, while focusing on Alzheimer’s disease (AD), dementia with Lewy bodies (DLB), and Parkinson’s disease dementia (PDD). A total of 34765 articles were retrieved from the seven electronic databases. After being screened by Participants, Index test, Control, Outcomes, Study design (PICOS) criteria, 129 articles for AD were included and then 72 articles were applied to the meta-analysis. However, five and six ar-ticles were systematically reviewed for the auditory functions of DLB and PDD, respectively,due to a small number of articles. The results of meta-analysis showed a significant difference between patients with AD and age-matched normal subjects, for N200 and P300 latency, P300 amplitude, and the behavioral central auditory processing tests, although there was a high heterogeneity. On the other hand, the systematic review indicated that the results of mismatch negativity test might distinguish auditory performance of DLB patients from that of PDD. Furthermore, for P300 amplitude, anterior to posterior distribution of brain resulted in meaningful difference of auditory function between AD and DLB patients. In sum, current review study suggests that lesion and degree of auditory (dys)function may be different depending on the type of dementia, although future research should be followed.

This study aimed to evaluate the efficacy of music training on the improvement of musical perception among hearing-impaired listeners using a systematic review and meta-analysis. Article search was conducted from five databases, Scopus, ScienceDirect, Web of Knowledge, CINAHL, and PubMed. A total of 186 participants from 10 studies investigating the music training effects on individuals fitted with hearing assistive devices and outcome measurements were included. The meta-analysis showed standardized mean difference as a measure of the effect size, in musical improvement between the preand post-training. Although the funnel plot yielded an asymmetrical graph, the Egger’s regression showed no significant publication bias. Interestingly, subgroup analysis showed that the training effect was greater in children than in adults. With a necessity of longer training period to significantly improve their musical perception, cochlear implant only users had better effect compared to bi-modal users with both cochlear implant and hearing aids. However, the difference in the training effect between the users with and without previous musical experience was nonsignificant. The present study concludes that auditory music training brings hearing-impaired listeners into better musical perception while informing that training effects differ depending on age, duration of the training, and the type of hearing device used.