Siti Zamratol Mai Sarah Mukari

Progress towards early detection services for infants with hearing loss in developing countries

BackgroundEarly detection of infants with permanent hearing loss through infant hearing screening is recognised and routinely offered as a vital component of early childhood care in developed countries. This article investigates the initiatives and progress towards early detection of infants with hearing loss in developing countries against the backdrop of the dearth of epidemiological data from this region.MethodsA cross-sectional, descriptive study based on responses to a structured questionnaire eliciting information on the nature and scope of early hearing detection services; strategies for financing services; parental and professional attitudes towards screening; and the performance of screening programmes. Responses were complemented with relevant data from the internet and PubMed/Medline.ResultsPilot projects using objective screening tests are on-going in a growing number of countries. Screening services are provided at public/private hospitals and/or community health centres and at no charge only in a few countries. Attitudes amongst parents and health care workers are typically positive towards such programmes. Screening efficiency, as measured by referral rate at discharge, was generally found to be lower than desired but several programmes achieved other international benchmarks. Coverage is generally above 90% but poor follow-up rates remain a challenge in some countries. The mean age of diagnosis is usually less than six months, even for community-based programmes.ConclusionLack of adequate resources by many governments may limit rapid nationwide introduction of services for early hearing detection and intervention, but may not deter such services altogether. Parents may be required to pay for services in some settings in line with the existing practice where healthcare services are predominantly financed by out-of-pocket spending rather than public funding. However, governments and their international development partners need to complement current voluntary initiatives through systematic scaling-up of public awareness and requisite manpower development towards sustainable service capacities at all levels of healthcare delivery.

Development and standardization of single and double dichotic digit tests in the Malay language

Single and double dichotic digit tests in Malay language were developed and standardized as an initial attempt to incorporate tests of auditory processing within the scope of audiology practice in Malaysia. Normative data under free recall, directed right-ear first, and directed left-ear first listening conditions were determined using 120 Malay children between the ages of 6 and 11 years old with normal hearing and normal academic performance. Test-retest reliability was assessed in 15 of the study subjects. In general, the double dichotic digit test produced greater differences in scores between age groups, and a greater right-ear advantage than the single dichotic digit test. In addition, the double dichotic digit test also had higher test-retest reliability. These findings suggest the double dichotic digit test is more clinically applicable.

Parents’ Evaluation of Aural/Oral Performance of Children (PEACH) scale in the Malay language: Data for normal-hearing children

Abstract The parents’ evaluation of aural/oral performance of children (PEACH) scale was developed to assess the effectiveness of amplification for children, based on a systematic use of parents’ observations of childrens performance in real-world environments. Objective: The purpose of the present study was to adapt the PEACH scale into the Malay language, and to collect normative data on a group of children with normal hearing. Study sample: The participants were parents of 74 children aged between 3 months and 13 years of age. Parents were requested to observe their childrens auditory/oral behavior in everyday life and to record their observations in the PEACH booklet. Results: High internal consistency (Cronbachs alpha = 0.93) and item-total correlation were found (0.52–0.85). Similar to the published norms for English-speaking children, near-perfect scores were achieved by Malaysian children around 40 months of age. Conclusions: The adapted version can be used to evaluate amplification for children in the Malay speaking environment. The normative curve relating age to scores for the Malay PEACH can be used as a reference against which functional aural/oral performance of hearing-impaired Malaysian children can be evaluated.

Effects of Ageing and Hearing Thresholds on Speech Perception in Quiet and in Noise Perceived in Different Locations

Background and Objectives This study investigated the effect of ageing on speech perception in quiet and in noise, with noise directed from front, right and left. Subjects and Methods Sixty Malay native adults with normal or near normal hearing comprising of 20 young adults (21 to 39 years old), 20 middle aged (40 to 59 years old) and 20 older adults (60 to 74 years old) participated in this study. Their speech perception ability was measured using the Malay Hearing in Noise Test (HINT) in four test conditions; 1) in quiet (HINT Q), 2) with noise from front (HINT NF), 3) with noise from right (HINT NR), and 4) with noise from left (HINT NL). Reception thresholds for sentences (RTSs) were measured in each of the aforementioned conditions using an adaptive method. Results The results showed that, 1) genuine age-related decline was found in speech perception performance in HINT (NF), 2) hearing threshold was a major determinant differentiating speech perception performance for HINT (Q) and HINT (NL) conditions, and 3) speech perception performance for HINT (NR) was determined by both age and hearing threshold. Conclusions This study suggests that, in older adults, while hearing thresholds affect speech perception in quiet, other factors such as central auditory processing and cognitive functions might be more important determinant factors for speech perception performance in noise.

Acoustic characteristics of vowels by normal Malaysian Malay young adults.

The acoustic characteristics of sustained vowel have been widely investigated across various languages and ethnic groups. These acoustic measures, including fundamental frequency (F(0)), jitter (Jitt), relative average perturbation (RAP), five-point period perturbation quotient (PPQ5), shimmer (Shim), and 11-point amplitude perturbation quotient (APQ11) are not well established for Malaysian Malay young adults. This article studies the acoustic measures of Malaysian Malay adults using acoustical analysis. The study analyzed six sustained Malay vowels of 60 normal native Malaysian Malay adults with a mean of 21.19 years. The F(0) values of Malaysian Malay males and females were reported as 134.85±18.54 and 238.27±24.06Hz, respectively. Malaysian Malay females had significantly higher F(0) than that of males for all the vowels. However, no significant differences were observed between the genders for the perturbation measures in all the vowels, except RAP in /e/. No significant F(0) differences between the vowels were observed. Significant differences between the vowels were reported for all perturbation measures in Malaysian Malay males. As for Malaysian Malay females, significant differences between the vowels were reported for Shim and APQ11. Multiethnic comparisons indicate that F(0) varies between Malaysian Malay and other ethnic groups. However, the perturbation measures cannot be directly compared, where the measures vary significantly across different speech analysis softwares.

Early and Late Shift of Brain Laterality in STG, HG, and Cerebellum with Normal Aging during a Short-Term Memory Task

Evidence suggests that cognitive performance deteriorates in noisy backgrounds and the problems are more pronounced in older people due to brain deficits and changes. The present study used functional MRI (fMRI) to investigate the neural correlates of this phenomenon during short-term memory using a forward repeat task performed in quiet (STMQ) and in noise: 5-dB SNR (STMN) on four groups of participants of different ages. The performance of short-term memory tasks was measured behaviourally. No significant difference was found across age groups in STMQ. However, older adults (50–65 year olds) performed relatively poorly on the STMN. fMRI results on the laterality index indicate changes in hemispheric laterality in the superior temporal gyrus (STG), Heschls gyrus (HG), and cerebellum, and a leftward asymmetry in younger participants which changes to a more rightward asymmetry in older participants. The results also indicate that the onset of the laterality shift varies from one brain region to another. STG and HG show a late shift while the cerebellum shows an earlier shift. The results also reveal that noise influences this shifting. Finally, the results support the hypothesis that functional networks that underlie STG, HG, and cerebellum undergo reorganization to compensate for the neural deficit/cognitive decline.

Development of a computer-based automated pure tone hearing screening device: a preliminary clinical trial

Abstract Hearing screening is important for the early detection of hearing loss. The requirements of specialized equipment, skilled personnel, and quiet environments for valid screening results limit its application in schools and health clinics. This study aimed to develop an automated hearing screening kit (auto-kit) with the capability of realtime noise level monitoring to ensure that the screening is performed in an environment that conforms to the standard. The auto-kit consists of a laptop, a 24-bit resolution sound card, headphones, a microphone, and a graphical user interface, which is calibrated according to the American National Standards Institute S3.6-2004 standard. The auto-kit can present four test tones (500, 1000, 2000, and 4000 Hz) at 25 or 40 dB HL screening cut-off level. The clinical results at 40 dB HL screening cut-off level showed that the auto-kit has a sensitivity of 92.5% and a specificity of 75.0%. Because the 500 Hz test tone is not included in the standard hearing screening procedure, it can be excluded from the auto-kit test procedure. The exclusion of 500 Hz test tone improved the specificity of the auto-kit from 75.0% to 92.3%, which suggests that the auto-kit could be a valid hearing screening device. In conclusion, the auto-kit may be a valuable hearing screening tool, especially in countries where resources are limited.

Self-Perceived Hearing Loss, Hearing-Help Seeking and Hearing Aid Adoption Among Older Adults in Malaysia

Introduction: The aims of this study were to examine the validity of self-perceived hearing loss in detecting hearing loss and factors associated with self-perceived hearing loss and hearing-help seeking and to report hearing aid adoption among a group of community-dwelling older adults in Malaysia. Methods: A total of 301 older adults (⩾60 years of age) participating in a study on aging had their hearing tested using pure-tone audiometry. Self-perceived hearing loss was assessed using a single question. Sociodemographic profile, otologic history, and general cognitive status were also obtained. Results: A single question had low sensitivity in detecting actual hearing loss: 31.3% for 4-frequency average > 25 dBHL and 48.8% for 4-frequency average > 40 dBHL. Besides hearing level, history of otorrhea and tinnitus were factors that were associated with self-perceived hearing loss among older adults with at least mild hearing loss. Hearing-help-seeking behavior was not associated with any of the tested variables. The hearing aid adoption rate was 2.7% and 7.3% among participants with 4-frequency averages > 25 dBHL and > 40 dBHL, respectively. Conclusion: The underestimation of hearing loss in the majority of older adults in this study poses a potential barrier to hearing loss intervention.

Effects of Aging and Background Babble Noise on Speech Perception Processing: An fMRI Study

Speech perception processing in a noisy environment is subjected to age-related decline. We used functional magnetic resonance imaging (fMRI) to examine cortical activation associated with such processing across four groups of participants with age ranges of 23–29, 30–37, 41–47 and 50–65 years old. All participants performed a forward repeat task in quiet environment (SQ) and in the presence of multi-talker babble noise (SN; 5-dB signal-to-noise ratio, SNR). Behavioral test results demonstrated a decrease in the performance accuracy associated with increasing age for both SQ and SN. However, a significant difference in the performance accuracy between these conditions could only be seen among the elderly (60–65 years old) subjects. The fMRI results across the four age groups showed a nearly similar pattern of brain activation in the auditory, speech, and attention areas during SQ and SN. Comparisons between SQ and SN demonstrated significantly lower brain activation in the left precentral gyrus, left postcentral gyrus, left Heschly’s gyrus, and right middle temporal gyrus under the latter condition. Other activated brain areas showed no significant differences in brain activation between SQ and SN. The decreases in cortical activation in the activated regions positively correlated with the decrease in the behavioral performance across age groups. These findings are discussed based on a dedifferentiation hypothesis that states that increased brain activation among older participants, as compared to young participants, is due to the age-related deficits in neural communication.

Validation of self-reported hearing loss among multi-ethnic community dwelling older adults in Malaysia

IntROduCtIOn Hearing loss has been identified as the third most reported chronic health problems affecting individuals aged 60 years and above [1]. The World Health Organization reported the prevalence of hearing loss among this age group to vary between 21% to 85%, with the prevalence being lower in developed nations and higher in less developed countries [2]. This discrepancy is partly due to the lack of awareness on hearing health and limited access to the services in lower income countries than those in developed countries. In Malaysia, a nationwide study found that the prevalence of hearing loss among the 60 years old and above was 69.9% [3].