Help-seeking behaviour of parents of children with hearing loss in India: a qualitative analysis.

OBJECTIVE: The age of identification of hearing loss in children is highly influenced by the hearing help seeking behaviour of their parents, particularly in countries without universal newborn hearing screening programs. In this study, an attempt was made to identify the factors associated with help seeking behaviour in parents of children with hearing loss, and the relationship of such factors with the age of identification of hearing loss. DESIGN: Focus group discussions based on the framework of health belief model were carried out. The discussions were transcribed and the transcripts were thematically analysed. STUDY SAMPLE: Participants were 35 parents of children with hearing loss from the state of Karnataka in India. RESULTS: The findings revealed 30 factors related to their awareness about hearing loss, geographical location, socio-economic status, family, and society. The factors differed between early and late help seekers. CONCLUSIONS: Awareness, accessibility, and affordability are the key factors that influenced the hearing help seeking behaviour of the participants. Effective public awareness programs, newborn hearing screening programs, and provisions to make hearing healthcare affordable to all can reduce the age of identification of paediatric hearing loss in India.

Recovery From Otitis Media and Associated Factors Among 1- to 6-Year-Old Children in South India: A Longitudinal Study.

BACKGROUND AND OBJECTIVES: This study was aimed at assessing recovery from otitis media (OM) and variables associated with it among 1- to 6-year-old children. Subjects and. METHODS: We assessed 87 children with OM otologically and audiologically. Medicines were prescribed, and medication compliance was ensured. The children were followed up after 3 months to judge the status of OM as resolved or recurrent. Data were statistically analyzed to derive the risk of recurrence of OM with effusion (OME) and acute OM by degree of hearing loss, type of tympanogram, age group, and sex. RESULTS: The overall recurrence rate was 26%. The risk of recurrence was higher for OME (odds ratio [OR]=4.33; 95% confidence interval [CI]: 1.90 to 9.83); at AC auditory brainstem peak V responses up to 40 dBnHL (OR=5.20; 95% CI: 2.05 to 13), 50 dBnHL (OR=3.47; 95% CI: 0.5 to 23), and 60 dBnHL (OR=16.09; 95% CI: 4.36 to 1.2); in B (OR= 3.16; 95% CI: 1.36 to 7.33) and C tympanograms (OR=2.83; 95% CI: 0.70 to 11.41); and in the age group of 5-6 years (OR=8, 95% CI: 2.23 to 28). The risk of recurrence of OM did not differ between male and female patients. CONCLUSIONS: The rate of recurrence was comparable to or lower than that reported in the pediatric population of other countries. The findings suggest that children with OME, severe pathology, or age of 5-6 years require more attention and frequent monitoring to minimize the risk of recurrence.

Simultaneous Multifrequency (SiMFy) Stimulus: A Novel and Reliable Stimulus for Frequency Tuning of Ocular Vestibular-Evoked Myogenic Potentials.

BACKGROUND: Frequency tuning of ocular vestibular evoked myogenic potential (oVEMP) refers to the frequency of tone burst that produces the largest amplitude oVEMP. There is an ever-growing pool of published studies that found the frequency tuning of oVEMP distinctly different in Ménière's disease than the age-matched controls and benign paroxysmal positional vertigo. However, recording oVEMP in response to many frequencies makes an already lengthy vestibular test battery even more cumbersome and time-consuming. PURPOSE: The aim of this study was to develop a novel time-saving stimulus that produces reliable results. RESEARCH DESIGN: Prospective study. STUDY SAMPLE: The study included 25 young, healthy adults. DATA COLLECTION: The tone-bursts of 2000, 1500, 1000, 750, 500, and 250 Hz were generated and sequenced in this order to prepare a stimulus for simultaneous multifrequency (SiMFy) oVEMP. The response parameters of SiMFy and conventional oVEMP methods were compared. RESULTS: No significant difference in peak-to-peak amplitude and frequency tuning existed between conventional and SiMFy oVEMP (p > 0.05). SiMFy had better test-retest reliability and was less time-consuming than the conventional oVEMP. CONCLUSIONS: SiMFy is a time-saving and reliable stimulus for obtaining frequency tuning of oVEMP with no compromise on the outcomes. It can be immediately applied in most commercially available evoked potential systems with a facility for loading an external stimulus.

Vowel Context Effect on the Perception of Stop Consonants in Malayalam and Its Role in Determining Syllable Frequency.

BACKGROUND AND OBJECTIVES: The study investigated vowel context effects on the perception of stop consonants in Malayalam. It also probed into the role of vowel context effects in determining the frequency of occurrence of various consonant-vowel (CV) syllables in Malayalam. Subjects and. METHODS: The study used a cross-sectional pre-experimental post-test only research design on 30 individuals with normal hearing, who were native speakers of Malayalam. The stimuli included three stop consonants, each spoken in three different vowel contexts. The resultant nine syllables were presented in original form and five gating conditions. The consonant recognition in different vowel contexts of the participants was assessed. The frequency of occurrence of the nine target syllables in the spoken corpus of Malayalam was also systematically derived. RESULTS: The consonant recognition score was better in the /u/ vowel context compared with /i/ and /a/ contexts. The frequency of occurrence of the target syllables derived from the spoken corpus of Malayalam showed that the three stop consonants occurred more frequently with the vowel /a/ compared with /u/ and /i/. CONCLUSIONS: The findings show a definite vowel context effect on the perception of the Malayalam stop consonants. This context effect observed is different from that in other languages. Stop consonants are perceived better in the context of /u/ compared with the /a/ and /i/ contexts. Furthermore, the vowel context effects do not appear to determine the frequency of occurrence of different CV syllables in Malayalam.

Effect of Hearing Aid Acclimatization on Speech-in-Noise Perception and Its Relationship With Changes in Auditory Long Latency Responses.

Objective The study attempted to track speech-in-noise perception and auditory long latency responses (ALLRs) over a period of hearing aid use in naïve hearing aid users. The primary aim was to investigate the relationship of change in speech-in-noise perception with the change in ALLRs. Method Thirty adults with mild-to-moderate sensorineural hearing loss (clinical group) and 17 adults with normal hearing (control group) in the age range of 23-60 years participated in the study. Syllable identification in noise (SIN) and ALLRs in noise were measured three times (three sessions) over a period of 2 months of hearing aid use. Results Results showed a significant increase in SIN and a decrease in the latency of ALLRs in the later sessions compared to the baseline session in the clinical group. However, the changes seen across the three sessions in the control group were not statistically significant. The magnitude of change in ALLRs seen in the clinical group did not significantly correlate with the change in SIN scores seen in them. Conclusions The study provides evidence for improvements in speech perception in noise and in processing time of auditory cortical areas with hearing aid acclimatization. However, it is important to note that the improvement in ALLRs does not assure improvement in speech perception in noise.

Effect of Music Training on Categorical Perception of Speech and Music.

BACKGROUND AND OBJECTIVES: The aim of this study is to evaluate the effect of music training on the characteristics of auditory perception of speech and music. The perception of speech and music stimuli was assessed across their respective stimulus continuum and the resultant plots were compared between musicians and non-musicians. SUBJECTS AND METHODS: Thirty musicians with formal music training and twenty-seven non-musicians participated in the study (age: 20 to 30 years). They were assessed for identification of consonant-vowel syllables (/da/ to /ga/), vowels (/u/ to /a/), vocal music note (/ri/ to /ga/), and instrumental music note (/ri/ to /ga/) across their respective stimulus continuum. The continua contained 15 tokens with equal step size between any adjacent tokens. The resultant identification scores were plotted against each token and were analyzed for presence of categorical boundary. If the categorical boundary was found, the plots were analyzed by six parameters of categorical perception; for the point of 50% crossover, lower edge of categorical boundary, upper edge of categorical boundary, phoneme boundary width, slope, and intercepts. RESULTS: Overall, the results showed that both speech and music are perceived differently in musicians and non-musicians. In musicians, both speech and music are categorically perceived, while in non-musicians, only speech is perceived categorically. CONCLUSIONS: The findings of the present study indicate that music is perceived categorically by musicians, even if the stimulus is devoid of vocal tract features. The findings support that the categorical perception is strongly influenced by training and results are discussed in light of notions of motor theory of speech perception.

Auditory and Cognitive Attributes of Hearing Aid Acclimatization in Individuals With Sensorineural Hearing Loss.

Purpose The study aimed to investigate the underlying mechanisms of perceived benefit of hearing aid acclimatization. Specifically, measures in the auditory and cognitive domain were tapped to investigate its relationship with the perceived benefit. Method Twenty-six individuals with sensorineural hearing loss served as participants for the study. The perceived benefit of hearing aid use was assessed using the Speech, Spatial and Qualities of Hearing Scale (SSQ; Gatehouse & Noble, 2004). Signal-to-noise ratio-50 (SNR-50) and acceptable noise levels were the measures in auditory domain, whereas working memory and listening effort (LE) were the measures in cognitive domain. All the measures were tracked over a span of 2 months of hearing aid use to determine the benefits of hearing aid acclimatization. Results The SSQ showed improvements from baseline to 2nd month of hearing aid use. The mean improvement in the SNR-50 scores was 3.19 dB from the baseline. Acceptable noise levels and working memory did not change with hearing aid use. LE showed improvements in quiet but not in noise. The improvements in the SSQ were found to relate with the improvements in SNR-50. Conclusions The study indicated a significant perceived benefit with hearing aid acclimatization, and the underlying mechanism appears to be the signal-to-noise ratio gain. The findings of LE indicated reduced LE, thereby suggesting lesser cognitive load with hearing aid acclimatization. In addition, the individuals who performed poorer in the baseline measurement showed greater perceived benefit with hearing aid acclimatization. Supplemental Material https://doi.org/10.23641/asha.9253175.

The Influence of Efferent Inhibition on Speech Perception in Noise: A Revisit Through Its Level-Dependent Function.

Purpose The study aimed to assess the relationship between the level-dependent function of efferent inhibition and speech perception in noise across different intensities of suppressor and across different signal-to-noise ratios (SNRs) of speech. Method Twenty-six young normal-hearing adults participated in the study. Contralateral suppression of transient evoked otoacoustic emissions (TEOAEs) was measured for 3 levels of suppressor (40, 50, and 60 dB SPL). Speech identification score (SIS) was measured at 5 ipsilateral SNR conditions (quiet, 0, -5, -10, and -15 dB), with and without contralateral broadband noise at 3 levels (40, 50, and 60 dB SPL). Furthermore, SNR-50 was measured with and without the same 3 levels of contralateral broadband noise. Results The results showed that the suppression magnitude of TEOAE increased with an increase in suppressor level. However, neither SIS nor SNR-50 was influenced by the contralateral noise. In addition, SIS and SNR-50 did not show significant correlation with contralateral suppression of TEOAEs. This was true at all the SNRs and contralateral noise levels used in the study. Conclusions The findings suggest that the intensity of noise directly influences medial olivocochlear bundle-mediated efferent inhibition. However, the role of the medial olivocochlear bundle in regulating speech perception in noise needs to be revisited. Supplemental Material https://doi.org/10.23641/asha.9336353.

Dichotic phase effects on frequency following responses reveal phase variant and invariant harmonic distortion products.

The dichotic frequency following responses (FFR) have been used in studies to infer about dichotic auditory processing. In the present study, we hypothesize that the proximity of the binaural neural generators of the FFR would result in interference of the volume-conducted electrical fields. This might lead to contamination of the scalp-recorded dichotic FFRs due to which it might be difficult to infer about true dichotic processing in the putative neural generators. We investigated this by recording FFRs to binaurally presented 200 Hz pure tone with graded dichotic phase offsets (0°, 90°, 180° and 270°) in normal hearing young adults. Spectral analysis of the FFRs was performed for the estimation of the magnitude and phase at the component frequencies. FFR spectra were compared using non-parametric paired randomizations within the subjects. We found that the brainstem responses to a 200 Hz pure tone consisted of prominent peaks at 200 Hz, and at frequencies corresponding to the harmonics of 200 Hz. The FFR spectral magnitude at 200 Hz diminished with a phase offset of 180°. Phase offsets of 90° and 270° showed reduced spectral magnitudes at 200 Hz than those in the 0° condition. Our findings, in line with the hypothesis, show that the dichotic FFRs do not reflect true dichotic processing and that they are contaminated during volume conduction. Additionally, we found harmonic distortion products (HDP) in the FFRs. We found that the response at 200 Hz and the 3rd HDP systematically varied with a change in phase of the stimulus, while the even HDPs (2nd and 4th) were phase-invariant. Based on our findings, and modeling FFRs using auditory models, we propose a rectification process as the contributors for the generation of HDPs. We also discuss the implications of this HDP generating mechanism in understanding the pitch represented in FFRs.

Consequences of hearing aid acclimatization on ALLRs and its relationship with perceived benefit and speech perception abilities.

OBJECTIVE: The study aimed to track long latency responses over a period of hearing aid use in naïve hearing aid users, and study its relationship with change in speech perception abilities and perceived benefit. METHODS: Thirty adults in the age range of 23-60 years with moderate sensorineural hearing loss participated in the study. Auditory late latency responses (ALLRs), signal-to-noise ratio - 50 (SNR-50), and scores of speech spatial and qualities questionnaire (SSQ) were measured three times over a period of 2 months of hearing aid use. RESULTS: ALLRs showed a significant decrease in the P1 and N1 latency across the three measurements. Significant increase in the scores of SSQ and significant decrease in the SNR-50 were also found. The change in ALLRs did not correlate with change in scores of either SSQ or SNR-50. CONCLUSIONS: The study provides evidence for improvements in neural processing of auditory cortical areas with hearing aid acclimatization. The improvements seen in perceived benefit and speech perception are not related to the improvements in ALLRs. This is the first study in the domain with a younger group compared to the previous studies and the results show evidence for neural plasticity influencing hearing aid acclimatization benefits.

Novel Paradigm to Record Bilateral Click-Evoked Auditory Brainstem Responses Simultaneously (BiSi-ABR).

OBJECTIVES: The current study proposes a new and fast technique to record the auditory brainstem responses (ABRs) simultaneously (BiSi-ABR) from two ears. The BiSi-ABR technique can be used to record the ABRs two times faster than with a conventional ABR recording method. The objective of the study was to show the proof of concept and to compare the BiSi-ABR technique with that of a conventional ABRs recording method to test its clinical feasibility. MATERIALS AND METHODS: A repeated-measures design was used, wherein ABRs recorded in the BiSi-ABR were compared with that of conventional ABRs recordings. Twenty-five normal-hearing adults participated in the study. ABRs were recorded using the BiSi-ABR technique, as well as the conventional method. The peak latencies (in ms) of waves III and V between the new technique and conventional method were compared. The minimum intensity at which the wave V was present was tracked using both the methods. RESULTS: The wave latencies and thresholds of ABR using the BiSi-ABR technique were remarkably similar to those recorded in the conventional ABR technique. The ABR wave latencies and thresholds did not differ significantly between the new technique and the conventional method. CONCLUSION: ABRs recorded with the BiSi-ABR technique can be used to estimate ear-specific hearing thresholds with the same reliability as that of conventional ABRs, in half the recording time. The results of the study have strong implications for screening, diagnostic, and research purposes as they aid in cutting down the ABR testing time.

Dynamics of Speech Perception in the Auditory-Visual Mode: An Empirical Evidence for the Management of Auditory Neuropathy Spectrum Disorders.

BACKGROUND AND OBJECTIVES: The present study probed into the relative and combined contribution of auditory and visual modalities in the speech perception of individuals with auditory neuropathy spectrum disorders (ANSD). Specifically, the identification scores of consonantvowel (CV) syllables, visual enhancement (VE), and auditory enhancement in different signal to noise ratios (SNRs) were compared with that of the control group. Subjects and. METHODS: The study used a repeated measure standard group comparison research design. Two groups of individuals in the age range of 16 to 35 years participated in the study. The clinical group included 35 participants diagnosed as ANSD, while the control group had 35 age and gender matched individuals with typical auditory abilities. The participants were assessed for CV syllable identification in auditory only (A), visual only (V), and auditory-visual (AV) modalities. The syllables were presented in quiet and at 0 dB SNR. RESULTS: The speech identification score was maximum in AV condition followed by A-condition and least in V condition. This was true in both the groups. The individuals with ANSD were able to make better use of visual cues than the control group, as evident in the VE score. CONCLUSIONS: The dynamics of speech perception in the AV mode is different between ANSD and control. There is definite benefit of auditory as well as visual cues to individuals with ANSD, suggesting the need to facilitate both the modalities as part of the audiological rehabilitation. Future studies can focus on independently facilitating the two modalities and testing the benefits in the AV mode of speech perception in individuals with ANSD.

Gender-bias in the sensory representation of infant cry.

The auditory neural pathway in females appears to be more sensitive to the cry of an infant (De Pisapia et al., 2013; Messina et al., 2016). Cortical responses in females have shown a distinct advantage compared to males in the auditory processing of infant cry. Such gender-bias in the cortical responses might emanate either at higher levels of processing such as cognitive and emotional processing or at the lower level representation of stimulus features. We assessed for a difference if any, between the two genders, in the sensory representation of an infant's cry. We used frequency following responses (FFR) to assess the sensory representation of an infant cry. This was done in sixteen male and fifteen female non-parent adults. The FFR closely mimics the stimulus acoustics with fine temporal precision and is the measure of choice to assess the sensory encoding of sounds in the auditory system. We performed spectral analysis of the FFRs and compared the spectral magnitudes between males and females. We found significantly higher FFR spectral magnitudes in females compared to males. The gender differences found were not related to the confounding variables such as head size or differences in the volume-conducting media. By systematically controlling other influencing variables, we show that the bias in neural processing of infant cry in females emerges right at the sensory representation levels.

Functional Interplay Between the Putative Measures of Rostral and Caudal Efferent Regulation of Speech Perception in Noise.

Efferent modulation has been demonstrated to be very important for speech perception, especially in the presence of noise. We examined the functional relationship between two efferent systems: the rostral and caudal efferent pathways and their individual influences on speech perception in noise. Earlier studies have shown that these two efferent mechanisms were correlated with speech perception in noise. However, previously, these mechanisms were studied in isolation, and their functional relationship with each other was not investigated. We used a correlational design to study the relationship if any, between these two mechanisms in young and old normal hearing individuals. We recorded context-dependent brainstem encoding as an index of rostral efferent function and contralateral suppression of otoacoustic emissions as an index of caudal efferent function in groups with good and poor speech perception in noise. These efferent mechanisms were analysed for their relationship with each other and with speech perception in noise. We found that the two efferent mechanisms did not show any functional relationship. Interestingly, both the efferent mechanisms correlated with speech perception in noise and they even emerged as significant predictors. Based on the data, we posit that the two efferent mechanisms function relatively independently but with a common goal of fine-tuning the afferent input and refining auditory perception in degraded listening conditions.

Acoustic basis of context dependent brainstem encoding of speech.

The newfound context dependent brainstem encoding of speech is evidence of online regularity detection and modulation of the sub-cortical responses. We studied the influence of spectral structure of the contextual stimulus on context dependent encoding of speech at the brainstem, in an attempt to understand the acoustic basis for this effect. Fourteen normal hearing adults participated in a randomized true experimental design in whom brainstem responses were recorded. Brainstem responses for a high pass filtered /da/ in the context of syllables, that either had same or different spectral structure were compared with each other. The findings suggest that spectral structure is one of the parameters which cue the context dependent sub-cortical encoding of speech. Interestingly, the results also revealed that, brainstem can encode pitch even with negligible acoustic information below the second formant frequency.

Distortion product otoacoustic emissions: comparison of sequential vs. simultaneous presentation of primary tones.

Distortion product otoacoustic emissions are one form of evoked otoacoustic emissions. DPOAEs provide the frequency specific information about the hearing status in mid and high frequency regions. But in most screening protocols TEOAEs are preferred as it requires less time compared to DPOAE. This is because, in DPOAE each stimulus is presented one after the other and responses are analyzed. Grason and Stadler Incorporation 60 (GSI-60) offer simultaneous presentation of four sets of primary tones at a time and checks for the DPOAE. In this mode of presentation, all the pairs are presented at a time and following that response is extracted separately whereas, in sequential mode primaries are presented in orderly fashion one after the other. In this article simultaneous and sequential protocols were used to compare the Distortion product otoacoustic emission amplitude, noise floor and administration time in individuals with normal hearing and mild sensori-neural (SN) hearing loss. In simultaneous protocols four sets of primary tones (i.e. 8 tones) were presented together whereas, in sequential presentation mode one set of primary tones was presented each time. Simultaneous protocol was completed in less than half the time required for the completion of sequential protocol. Two techniques yielded similar results at frequencies above 1000 Hz only in normal hearing group. In SN hearing loss group simultaneous presentation yielded signifi cantly higher noise floors and distortion product amplitudes. This result challenges the use of simultaneous presentation technique in neonatal hearing screening programmes and on other pathologies. This discrepancy between two protocols may be due to some changes in biomechanical process in the cochlear and/or due to higher distortion/noise produced by the system during the simultaneous presentation mode.

Effect of early onset otitis media on brainstem and cortical auditory processing.

BACKGROUND: Otitis media (OM) leads to significant reduction in the hearing sensitivity. The reduced auditory input, if in the early years of life when the auditory neural system is still maturing, may adversely influence the structural as well as functional development of the system. Past research has reported abnormalities in both the structure and function of brainstem nuclei following auditory deprivation, but, it has not necessarily focused on children who had OM in their first year of life. It can also be said that if auditory processing is affected at the brainstem level because of early onset OM (reduced auditory input in the crucial periods of neural development), then, it may be said that auditory processing is also affected at the cortical level because it receives distorted input from the brainstem. Therefore, the purpose of this study was to document the effects of early onset OM on auditory processing, if any, at the brainstem as well as at cortical levels. A related purpose of the study was to investigate the persistence of the effects of early onset OM, if any, on auditory processing. METHODS: A cross sectional approach and a standard group comparison design was used in the study. Thirty children, who had OM between 6 and 12 months of age and who were in the age range of 3.1 - 5.6 years participated in the study. Children with OM were divided into 3 groups based on their age. Click evoked auditory brainstem responses (ABRs) and late latency responses (LLRs) were recorded from these children, and the responses were compared with those from age and gender matched normal children without any history of OM. The data from the 2 groups was statistically analyzed through independent t test. Pearson's Product Moment correlation was computed to examine the relationship between results of ABR and LLR in children with early onset OM. RESULTS: The mean central conduction time was significantly increased and the mean amplitude of wave I and III of ABRs was significantly reduced in children with early onset OM compared to normal children. Also, the latency of all LLR waves was significantly less in children with early onset OM than in normal children. However, significant differences in mean values of either ABR or LLR (latencies or interwave intervals as the case may be) were observed only in 3-year old children. There was a significant, but negative association between central conduction time and latency of LLRs. CONCLUSION: OM in the first year of life leads to negative effects on brainstem signal processing even if it has occurred only for a short duration (maximum of 3 months). In such a situation, auditory cortical structures probably show compensatory changes through central gain to offset the prolonged central conduction time. Although the results of the present study showed that the negative effects of early onset OM (occurring in the first year of life) on auditory processing disappeared by the time the children were 4.1 years, there is need for longitudinal studies on this to confirm the findings.

Mismatch negativity in children with dyslexia speaking Indian languages.

BACKGROUND: Several studies in the past have found that phonological processing is abnormal in children with dyslexia. Phonological processing depends on the phonological rules of the language learnt. Western languages do not have a good phoneme to grapheme correspondence while many of the Indian languages do have it. Also phonological rules of western languages are different from that of Indian languages. Thus it would be erroneous to generalize the results of phonological processing obtained on children speaking western languages to those speaking Indian languages. Hence the present study was aimed to investigate the auditory processing in children with dyslexia who spoke and studied Indian languages. METHODS: Standard group comparison design was used in the study. The study was conducted on fifteen children with dyslexia and fifteen control children. Mismatch negativity was elicited for speech and tonal stimuli. Results obtained on the clinical group were compared with that of control group using mixed design Analysis of variance. Children in both the groups were native speakers of Kannada (a south Indian language). RESULTS: A subgroup of children showed abnormalities in the processing of speech and/or tonal stimuli. Speech elicited mismatch negativity showed greater abnormalities than that of tonal stimuli. Though higher for spectral contrasts, processing deficits were also shown for durational contrasts. CONCLUSION: Inspite of having different phonological rules and good phoneme-grapheme correspondence in Indian languages, children with dyslexia do have deficits in processing both spectral and durational cues.