Speech audiometry is a method for assessing the ability of the auditory system using speech sounds as stimuli. A list of phonemically balanced bisyllabic consonant-vowel-consonant-vowel (c-v-c-v) Malay words was produced. All the bisyllabic words (c-v-c-v) thought to be commonly used in everyday conversations were listed from the Dewan Bahasa dictionary and their suitability assessed. The chosen words were divided into 25 groups containing 10 words each. The list was then recorded by a professional male newscaster in a sound proof studio. A normal speech audiometry curve was obtained by testing 60 normal hearing subjects using the prerecorded speech material. The result of the study showed that the normal Malay speech audiometry curve was comparable to those of English and Arabic speech audiometry, in which it was sigmoidal with the optimum discrimination score of 40 dB and half peak level of 17.5 dB.
This study assessed the effects of age and working memory capacity on dichotic listening and temporal sequencing. Double Dichotic Digit Test (DDT), Pitch Pattern Sequence Test (PPST) and Digit Span Test were administered on 40 healthy adults with hearing thresholds of not greater than 30 dB HL across octave frequencies from 250 to 4000 Hz. Twenty young (20-30 years old) and 20 older (50-65 years old) adults were included in the study. Results showed that the older group had significantly lower scores in DDT, PPST and working memory capacity measures than the young subjects. Working memory capacity was positively correlated with PPST but not with DDT, suggesting that DDT might be more auditory-modality-specific than PPST.
The purposes of this study were to: (1) compare medial olivocochlear system (MOCS) functioning and speech perception in noise in young and older adults and (2) to quantify the correlation between MOCS functioning and speech perception in noise. Measurements were taken in 20 young (mean 26.3 +/- 2.1 years) and 20 older adults (mean 55.2 +/- 2.8 years). Contralateral distortion product otoacoustic emission (DPOAE) suppression was measured to assess MOCS functioning. Speech perception in noise was evaluated using the Hearing in Noise Test in noise-ipsilateral, noise-front and noise-contralateral test conditions. The results revealed that the older group had a significantly lower high-frequency (3-8 kHz) contralateral DPOAE suppression, and performed more poorly in the noise-ipsilateral condition than the younger group. However, there was no correlation between contralateral DPOAE suppression and speech perception in noise. This study suggests that poor speech perception performance in noise experienced by older adults might be due to a decline in medial olivocochlear functioning, among other factors.
The present study documents the school performance of 20 pediatric cochlear implant recipients who attended mainstream classes and compares their educational performance with their normally hearing peers.
This paper reports the performance of a newly implemented hospital-based universal newborn hearing screening programme and the challenges to the effective implementation.
Post meningitic sensori-neural hearing loss was studied in forty new cases of bacterial meningitis and ten cases of viral meningitis treated at the Pediatric Institute, Kuala Lumpur Hospital from April 1991 to March 1992. Hearing assessment at 2 weeks, 3 months and 6 months following the diagnosis of meningitis using Brain Stem Evoked Response Audiometry showed that hearing loss was prevalent only in patients with bacterial meningitis. Hearing loss was detected in 32.5% of these patients during the acute phase of the disease, 22.8% after 3 months and 24.2% after 6 months. In 63.6% of the affected cases, hearing loss was bilateral. In 61.5% of the patients who had hearing loss during the acute phase of the disease, it was permanent, 16.7% had either partial or complete recovery and, 15.4% had deterioration in hearing level. In 2 cases the subsequent hearing level was unknown. The risk of developing sensori neural hearing loss was found to be significantly higher in patients who developed other neurological sequelae. The study highlights the importance of performing repeated hearing assessment in children with bacterial meningitis and the difficulty in appropriate selection of hearing aids in the early stages.
In the present study, brain activation associated with speech perception processing was examined across four groups of adult participants with age ranges between 20 and 65 years, using functional MRI (fMRI). Cognitive performance demonstrates that performance accuracy declines with age. fMRI results reveal that all four groups of participants activated the same brain areas. The same brain activation pattern was found in all activated areas (except for the right superior temporal gyrus and right middle temporal gyrus); brain activity was increased from group 1 (20-29 years) to group 2 (30-39 years). However, it decreased in group 3 (40-49 years) with further decreases in group 4 participants (50-65 years). Result also reveals that three brain areas (superior temporal gyrus, Heschl's gyrus and cerebellum) showed changes in brain laterality in the older participants, akin to a shift from left-lateralized to right-lateralized activity. The onset of this change was different across brain areas. Based on these findings we suggest that, whereas all four groups of participants used the same areas in processing, the engagement and recruitment of those areas differ with age as the brain grows older. Findings are discussed in the context of corroborating evidence of neural changes with age.
The present study aimed to determine levels of parents' satisfaction associated with the universal newborn hearing screening process in a university hospital setting in Kuala Lumpur, Malaysia.
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 children's performance in real-world environments.
The aim of the present study was to compare the benefit of monaural versus binaural ear-level frequency modulated (FM) fitting on speech perception in noise in children with normal hearing. Reception threshold for sentences (RTS) was measured in no-FM, monaural FM, and binaural FM conditions in 22 normally developing children with bilateral normal hearing, aged 8 to 9 years old. Data were gathered using the Pediatric Malay Hearing in Noise Test (P-MyHINT) with speech presented from front and multi-talker babble presented from 90°, 180°, 270° azimuths in a sound treated booth. The results revealed that the use of either monaural or binaural ear level FM receivers provided significantly better mean RTSs than the no-FM condition (P<0.001). However, binaural FM did not produce a significantly greater benefit in mean RTS than monaural fitting. The benefit of binaural over monaural FM varies across individuals; while binaural fitting provided better RTSs in about 50% of study subjects, there were those in whom binaural fitting resulted in either deterioration or no additional improvement compared to monaural FM fitting. The present study suggests that the use of monaural ear-level FM receivers in children with normal hearing might provide similar benefit as binaural use. Individual subjects' variations of binaural FM benefit over monaural FM suggests that the decision to employ monaural or binaural fitting should be individualized. It should be noted however, that the current study recruits typically developing normal hearing children. Future studies involving normal hearing children with high risk of having difficulty listening in noise is indicated to see if similar findings are obtained.
Transient-evoked otoacoustic emission (TEOAE) is a well-established screening tool for universal newborn hearing screening. The aims of this study are to measure the effects of background noise on recording of TEOAE and the duration required to complete the test at various noise levels. This study is a prospective study from June 2006 until May 2007. The study population were newborns from postnatal wards who were delivered at term pregnancy. Newborns who were more than 8-h old and passed a hearing screening testing using screening auditory brainstem response (SABRe) were further tested with TEOAE in four different test environments [isolation room in the ward during non-peak hour (E1), isolation room in the ward during peak hour (E2), maternal bedside in the ward during non-peak hour (E3) and maternal bedside in the ward during peak hour (E4)]. This study showed that test environment significantly influenced the time required to complete testing in both ears with F [534.23] = 0.945; P < 0.001 on the right ear and F [636.54] = 0.954; P < 0.001 on the left. Our study revealed that TEOAE testing was efficient in defining the presence of normal hearing in our postnatal wards at maternal bedside during non-peak hour with a specificity of 96.8%. Our study concludes that background noise levels for acceptable and accurate TEOAE recording in newborns should not exceed 65 dB A. In addition, when using TEOAE assessment in noisy environments, the time taken to obtain accurate results will greatly increase.
The aims of the present study were to determine the effects of language background on the performance of the pitch pattern sequence test (PPST) and duration pattern sequence test (DPST). As temporal order sequencing may be affected by age and working memory, these factors were also studied.
We surveyed parents of school-aged hearing impaired children to investigate their awareness and knowledge of the special needs of their child, especially in the area of the usage of hearing aids and methods of communication. Questionnaires were distributed to parents of hearing impaired children at 13 special schools for the deaf in Malaysia. Out of 1,267 questionnaires given out, 787 (62.1%) were completed and returned. Results of the survey indicated the majority of parents (68.6%) suspected hearing loss late, that is after their child's first birthday, and there was a significant time lag before the suspicion was confirmed. Over 82.8% of the children were diagnosed only after 1 year of age, with 41.3% being diagnosed after 3 years of age. Hearing aids were fitted late (mean = 5.32 years; SD = 2.66). Hearing aid ownership was influenced by the factors of socio-economic level and ethnic group (p < 0.01) whereas knowledge of use and proper care of the aids was influenced by socio-economic level (p < 0.01). Communication methods were generally inappropriate with 41.3% of the mothers and 48.5% of the fathers reporting ignorance of Bahasa Malaysia Kod Tangan, the sign language that is commonly used by their children. The parents' choice of communication method was not significantly influenced by socio-economic level or ethnic group. The study revealed the present inadequate state of services available for the rehabilitation of children with congenital hearing impairment.
Despite the commonly observed condition of middle and inner ear barotrauma among divers, there is little evidence of insidious and permanent development of sensorineural hearing loss associated with diving. An audiometric survey was performed on a group of 120 divers and 166 non divers from the Royal Malaysian Naval Base in Lumut, West Malaysia between July to December 1991. The results of this survey revealed that insidious development of high frequency sensorineural hearing loss may be associated with diving. At frequencies 4000, 6000 and 8000 Hz the divers had higher mean hearing levels than non divers and their hearing at those frequencies seemed to deteriorate faster. The etiology of this insidious hearing loss is multifactorial and may be related to inner ear barotrauma, decompression sickness or noise-induced deafness.
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.
To examine the changes in the short-term auditory memory following the use of frequency-modulated (FM) system in children with suspected auditory processing disorders (APDs), and also to compare the advantages of bilateral over unilateral FM fitting.
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), Heschl's 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.
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.