Background and purpose: Gender disparities in auditory brainstem response (ABR) results have been reported but the exact reasons remain controversial. Difference in head size between genders has been suggested but the literature is lacking, particularly at threshold levels. In this short communication, we compared ABR results between males and females with comparable head sizes at supra-threshold and threshold levels. Materials and methods: In this comparative study, of 58 healthy young adults, 30 of them (17 females and 13 males) with comparable head sizes underwent the standard ABR testing. Wave V latencies and ABR thresholds were determined and analyzed accordingly.Results: At the supra-threshold level, significantly shorter wave V latencies were found in females than in males (p = 0.029). This difference was substantive (d = 0.86) and persisted even when the head size was included in the analysis (p = 0.032). In contrast, no significant differences in ABR thresholds were found between genders (p > 0.05). Conclusions: Significant gender differences in ABR results among young adults were only found at the supra-threshold level, which were not related to the head size. Based on the study outcomes, gender-specific normative data for ABR are still beneficial for clinical applications, particularly when recording ABR at high stimulation levels.

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For estimating behavioral hearing thresholds, auditory steady state response (ASSR) can be reliably evoked by stimuli at low and high modulation frequencies (MFs). In this regard, little is known regarding ASSR thresholds evoked by stimuli at different MFs in female and male participants. In fact, recent data suggest that 40-Hz ASSR is influenced by estrogen level in females. Hence, the aim of the present study was to determine the effect of gender and MF on ASSR thresholds in young adults. Twenty-eight normally hearing participants (14 males and 14 females) were enrolled in this study. For each subject, ASSR thresholds were recorded with narrow-band chirps at 500, 1,000, 2,000, and 4,000 Hz carrier frequencies (CFs) and at 40 and 90 Hz MFs. Two-way mixed ANOVA (with gender and MF as the factors) revealed no significant interaction effect between factors at all CFs (p > 0.05). The gender effect was only significant at 500 Hz CF (p < 0.05). At 500 and 1,000 Hz CFs, mean ASSR thresholds were significantly lower at 40 Hz MF than at 90 Hz MF (p < 0.05). Interestingly, at 2,000 and 4,000 Hz CFs, mean ASSR thresholds were significantly lower at 90 Hz MF than at 40 Hz MF (p < 0.05). The lower ASSR thresholds in females might be due to hormonal influence. When recording ASSR thresholds at low MF, we suggest the use of gender-specific normative data so that more valid comparisons can be made, particularly at 500 Hz CF.

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IntroductionThe Malay language is an Austronesian language spoken by the Malay people in Malaysia, southern Thailand, the Philippines, Singapore, central eastern Sumatra, the Riau Islands, and parts of the coast of Borneo. It is an official language of Malaysia, Brunei, and Singapore. In Malaysia, the Malay language, also known as Bahasa Melayu or Bahasa Malaysia, is the national language of the country. This report summarizes the procedures for developing the hearing in noise test in Malay language. Method and Results Test materialA corpus of 724 three to five word (six to nine syllables) sentences was compiled. These sentences were written by five audiologists and a linguist. The 144 sentences of 'unsure naturalness' or rated 'unnatural' (3 or higher on a scale of 1 to 5) by six native speakers were reviewed and modified by the linguist. The resulting sentences were recorded at the House Ear Institute by a native male speaker of Malay with a trained voice. Estimate of the performance-intensity functionThree lists of 50 randomly selected sentences were presented at signal to noise ratios (S/N ratios) of (3 dB, (5 dB, and (8 dB to 10 listeners of ages 20 to 40 years. These subjects had hearing thresholds that were 25 dB HL or better at audiometric frequencies from 250 to 8000 Hz in both ears. The estimated performance intensity (PI) function slope was 9.8% intelligibility change per 1-dB change in S/N ratio. Equalization of sentence difficultyTwo groups of 10 subjects, each with normal hearing as defined above, participated in the equalization study. Percent intelligibility for each sentence was measured initially at a (5 dB S/N ratio with noise fixed at 65 dBA. The RMS levels of sentences were adjusted using the slope of the PI function to achieve the target of 70% word intelligibility for each sentence. After two rounds of testing, 285 sentences were scaled to an average of (6 dB S/N ratio, with 87% of sentences having levels within 92 dB of the average level for all sentences. The average intelligibility of all of the selected sentences was within the range of 70%915%. Formation of sentence listsThe 285 sentences were used to form 28 phonemically balanced 10-sentence lists. After balancing, 92% of the phoneme distributions within the lists were within92.5% of the distribution means for the entire set of sentences. There were 5128 phonemes; of which, 44.2% were vowels and 55.8% were consonants. The vowel /a/ was the most frequently occurring vowel (35.1%), and /t/ was the most frequently occurring consonant (10.2%).Reception thresholds for sentences (RTSs) measured on six subjects using the 25 10-sentence lists, ranged from (5.5 dB to (3.5 dB S/N ratio. Standard deviations were low (0.8 dB to 3.9 dB). A one-way analysis of variance showed no significant differences between RTSs across lists (p0.05). When the list that had the highest standard deviation value (3.9 dB) was removed, the other lists were paired to form twelve 20-sentence lists, and the mean RTSs ranged from (4.3 dB to (4.8 dB S/N ratio. Development...