Tonal Masking Level Differences in Aboriginal Children: Implications for Binaural Interaction, Auditory Processing Disorders and Education

Wideband Absorbance Predicts the Severity of Conductive Hearing Loss in Children With Otitis Media With Effusion

OBJECTIVES

The objectives of the present study were to investigate the relationship between wideband absorbance (WBA) and air-bone gap (ABG) in children with a conductive hearing loss (CHL) due to otitis media with effusion (OME) and determine the accuracy of WBA to predict the magnitude of ABGs.

DESIGN

This was a prospective, cross-sectional study involving a control group of 170 healthy ears from 130 children (mean age 7.7 years) and a CHL cohort of 181 ears from 176 children (mean age 5.9 years) with OME. The CHL cohort was divided into three groups: CHL1, CHL2, and CHL3 defined by mean ABG (averaged across 0.5 to 4 kHz) of 16 to 25 dB, 26 to 35 dB, and 36 to 45 dB, respectively. WBA was measured at frequencies from 0.25 to 8 kHz at ambient pressure.

RESULTS

WBA was significantly reduced between 0.25 and 5 kHz for all CHL groups. The difference in WBA at 1 to 4 kHz between the control and CHL groups increased with increasing ABG. The predictive accuracy, as indicated by area under the receiver operating characteristic curve (AUROC) of WBA, increased with increasing ABG. The AUROC for WBA at 1.5 kHz was 0.86 for the CHL1, 0.91 for the CHL2, and 0.93 for the CHL3 group. The AUROCs for WBA averaged across 0.5 to 4 kHz were 0.88, 0.93, and 0.94 for the CHL1, CHL2, and CHL3 groups, respectively. Linear regression analyses showed significant negative correlations between WBA 0.5-4 k and ABG 0.5-4 k . The regression model (ABG 0.5-4 k = 31.83 - 24.08 × WBA 0.5-4 k ) showed that WBA 0.5-4 k predicted ABG 0.5-4 k with high accuracy. Comparison of predicted and actual WBA on a different group of subjects revealed that at an individual level, the model predicted ABG between 16 and 35 with greater precision.

CONCLUSIONS

There were significant strong correlations between WBA and ABG such that WBA decreased with increasing ABG. WBA demonstrated good discrimination accuracy with AUROC exceeding 0.88 for the 0.5 to 4 kHz and 1 to 4 kHz frequency bands. The WBA test holds promise for determining the severity of CHL in children with OME.

Binaural masking level difference for pure tone signals

The binaural masking level difference (BMLD) is a psychoacoustic method to determine binaural interaction and central auditory processes. The BMLD is the difference in hearing thresholds in homophasic and antiphasic conditions. The duration, phase and frequency of the stimuli can affect the BMLD. The main aim of the study is to evaluate the BMLD for stimuli of different durations and frequencies which could also be used in future electrophysiological studies. To this end we developed a GUI to present different frequency signals of variable duration and determine the BMLD. Three different durations and five different frequencies are explored. The results of the study confirm that the hearing threshold for the antiphasic condition is lower than the hearing threshold for the homophasic condition and that differences are significant for signals of 18ms and 48ms duration. Future objective binaural processing studies will be based on 18ms and 48ms stimuli with the same frequencies as used in the current study.

Dichotic listening is associated with phonological awareness in Australian aboriginal children with otitis media: A remote community-based study

OBJECTIVE

Recent literature has highlighted a link between hearing loss as a result of otitis media in the early years of life and impacted binaural processing skills in later childhood. Such findings are of particular relevance to Indigenous Australian children, who tend to experience otitis media earlier in life and for longer periods than their non-Indigenous counterparts. There is also growing interest in the effects of reduced auditory processing ability on a child's early learning of language and, specifically, on phonological awareness that contributes to word reading skills. The aim of the present study was to determine the association between hearing thresholds, dichotic listening skills and phonological awareness in children with pervasive otitis media (OM) from remote Indigenous communities of Australia who generally do not speak English as a first language.

METHODS

Participants included one hundred and one children between the ages of 4.8-7.9 years (mean 6.1 years) from three separate remote Northern Territory communities. Evaluations included otoscopy, air conduction PTA, and tympanometry. All children were also assessed on the Dichotic Digits difference test (DDdT) and the Foundations of Early Literacy Assessment (FELA), assessing children's dichotic listening and phonological awareness respectively.

RESULTS

The results showed that 56% of the children had middle ear dysfunctions (type B and type C on tympanometry results) in at least one ear on the day. Partial correlation showed a significant correlation, between dichotic scores and FELA with age as covariate (r = 0.45, p < 0.001). One way ANOVA showed females exhibited a significantly higher performance compared to males on FELA [F (1, 99) = 5.47, p = 0.021]. The overall regression model was found to be significant in predicting total FELA scores [F (7, 77) = 7.56, p < 0.0005]. Age and gender as well as dichotic listening scores explain 40.7% of the variance.

CONCLUSIONS

The results reinforce the importance of managing the ear health of Indigenous children, clarifying the impact this has on listening and phonological awareness. These findings highlight the importance of evaluating children's listening abilities, and how poor listening can impact phonological awareness. The findings have important implications for ensuring optimal listening and learning conditions in schools in remote NT communities.

Reading Between the Lines: Neurocognition and Reading Acquisition in Remote Indigenous Australia

Successful academic progression relies on a child’s ability to develop proficient reading skills. In Australia, the majority of children achieve this milestone during elementary schooling. Yet Australian Indigenous children, particularly those living in remote and rural regions of Australia, consistently struggle to meet national benchmarks for reading, as evidenced by national benchmark data. There has been extensive debate about whether sociocultural factors impinge on academic achievement for Indigenous Australians, but little discussion regarding the possible role of neurocognitive factors. In this review, we consider limited available research on neurocognitive mechanisms associated with reading for Indigenous populations and argue for an urgent need to consider the relationship between neurocognitive and sociocultural development when examining reading acquisition outcomes for this population. We also discuss the plausibility of targeting the potential neurocognitive strengths of certain Indigenous populations to scaffold reading acquisition and identify opportunities for furthering this line of research.

Abnormalities in cortical auditory responses in children with central auditory processing disorder

The main objective of the present study was to identify markers of neural deficits in children with central auditory processing disorder (CAPD) by measuring latency and amplitude of the auditory cortical responses and mismatch negativity (MMN) responses. Passive oddball paradigms were used with nonverbal and verbal stimuli to record cortical auditory-evoked potentials and MMN. Twenty-three children aged 9-12 participated in the study: 10 with normal hearing acuity as well as CAPD and 13 with normal hearing without CAPD. No significant group differences were observed for P1 latency and amplitude. Children with CAPD were observed to have significant N2 latency prolongation and amplitude reduction with nonverbal and verbal stimuli compared to children without CAPD. No significant group differences were observed for the MMN conditions. Moreover, electrode position affected the results in the same manner for both groups of children. The findings of the present study suggest that the N2 response could be a marker of neural deficits in children with CAPD. N2 results suggest that maturational factors or a different mechanism could be involved in processing auditory information at the central level for these children.

Characteristics of Auditory Processing Disorders: A Systematic Review

PURPOSE

The purpose of this review article is to describe characteristics of auditory processing disorders (APD) by evaluating the literature in which children with suspected or diagnosed APD were compared with typically developing children and to determine whether APD must be regarded as a deficit specific to the auditory modality or as a multimodal deficit.

METHOD

Six electronic databases were searched for peer-reviewed studies investigating children with (suspected) APD in comparison with typically developing peers. Relevant studies were independently reviewed and appraised by 2 reviewers. Methodological quality was quantified using the American Speech-Language-Hearing Association's levels of evidence.

RESULTS

Fifty-three relevant studies were identified. Five studies were excluded because of weak internal validity. In total, 48 studies were included, of which only 1 was classified as having strong methodological quality. Significant dissimilarities were found between children referred with listening difficulties and controls. These differences relate to auditory and visual functioning, cognition, language, reading, and physiological and neuroimaging measures.

CONCLUSIONS

Methodological quality of most of the incorporated studies was rated moderate due to the heterogeneous groups of participants, inadequate descriptions of participants, and the omission of valid and reliable measurements. The listening difficulties of children with APD may be a consequence of cognitive, language, and attention issues rather than bottom-up auditory processing.

Comorbidity of auditory processing, language, and reading disorders

PURPOSE

The authors assessed comorbidity of auditory processing disorder (APD), language impairment (LI), and reading disorder (RD) in school-age children.

METHOD

Children (N = 68) with suspected APD and nonverbal IQ standard scores of 80 or more were assessed using auditory, language, reading, attention, and memory measures. Auditory processing tests included the Frequency Pattern Test (FPT; F. E. Musiek, 1994; D. Noffsinger, R. H. Wilson, & F. E. Musiek, 1994); the Dichotic Digit Test Version 2 (DDT; F. E. Musiek, 1983); the Random Gap Detection Test (R. W. Keith, 2000); the 500-Hz tone Masking Level Difference (V. Aithal, A. Yonovitz, & S. Aithal, 2006); and a monaural low-redundancy speech test (compressed and reverberant words; A. Boothroyd & S. Nittrouer, 1988). The Clinical Evaluation of Language Fundamentals, Fourth Edition (E. Semel, E. Wiig, & W. Secord, 2003) was used to assess language abilities (including auditory memory). Reading accuracy and fluency and phonological awareness abilities were assessed using the Wheldall Assessment of Reading Passages (A. Madelaine & K. Wheldall, 2002) and the Queensland University Inventory of Literacy (B. Dodd, A. Holm, M. Orelemans, & M. McCormick, 1996). Attention was measured using the Integrated Visual and Auditory Continuous Performance Test (J. A. Sandford & A. Turner, 1995).

RESULTS

Of the children, 72% had APD on the basis of these test results. Most of these children (25%) had difficulty with the FPT bilaterally. A further 22% had difficulty with the FPT bilaterally and had right ear deficits for the DDT. About half of the children (47%) had problems in all 3 areas (APD, LI, and RD); these children had the poorest FPT scores. More had APD-RD, or APD-LI, than APD, RD, or LI alone. There were modest correlations between FPT scores and attention and memory, and between DDT scores and memory.

CONCLUSIONS

LI and RD commonly co-occur with APD. Attention and memory are linked to performance on some auditory processing tasks but only explain a small amount of the variance in scores. Comprehensive assessment across a range of areas is required to characterize the difficulties experienced by children with APD.