Background and Aim: Digits are suitable speech materials for evaluating recognition of speech-in-noise in clients with the wide range of language abilities. Farsi Auditory Recognition of Digit-in-Noise (FARDIN) test has been deve­loped and validated in learning-disabled child­ren showing dichotic listening deficit. This stu­dy was conducted for further validation of FARDIN and to survey the effects of noise type on the recognition performance in individuals with sensory-neural hearing impairment. Methods: Persian monosyllabic digits 1−10 were extracted from the audio file of FARDIN test. Ten lists were compiled using a random order of the triplets. The first five lists were mixed with multi-talker babble noise (MTBN) and the second five lists with speech-spectrum noise (SSN). Signal- to- noise ratio (SNR) var­ied from +5 to −15 in 5 dB steps. 20 normal hearing and 19 hearing-impaired individuals participated in the current study. Results: Both types of noise could differentiate the hearing loss from normal hearing. Hearing-impaired group showed weaker performance for digit recognition in MTBN and SSN and needed 4−5.6 dB higher SNR (50%), compared to the normal hearing group. MTBN was more challenging for normal hearing than SSN. Conclusion: Farsi Auditory Recognition of Digit-in-Noise is a validated test for estimating SNR (50%) in clients with hearing loss. It seems SSN is more appropriate for using as a back­ground noise for testing the performance of aud­itory recognition of digit-in-noise.   Keywords: Auditory recognition; hearing loss; speech perception in noise; digit recognition in noise

Objectives Directional microphone technology can enhance the speech intelligibility and listening comfort of listeners with hearing impairment. The main aim of this study is to investigate and compare the benefit derived by listeners with severe hearing loss from directional microphone technology with that derived by listeners with moderate hearing loss.Methods The acceptable noise levels (ANLs) of two groups of listeners with moderate or severe hearing impairment (17 subjects in each group) were measured under unaided, omnidirectional-baseline-aided, and directional-aided conditions.Results Although the absolute ANL of the listeners in the severe hearing loss group was significantly higher than that of the listeners in the moderate hearing loss group, their derived benefit was equivalent to that derived by the listeners in the moderate hearing loss group. ANL and hearing loss degree were significantly related. Specifically, the ANL increased with the severity of hearing loss.Conclusion Directional microphone technology can provide the benefits of listening comfort to listeners with severe hearing loss.

Background: Previous studies have reported the weakness of recognition of speech-in-noise and dichotic listening deficit in Learning-Disabled (LD) children. This study aimed at further investigating these two deficits in LD children.

Objectives Two main digital signal processing technologies inside the modern hearing aid to provide the best conditions for hearing aid users are directionality (DIR) and digital noise reduction (DNR) algorithms. There are various possible settings for these algorithms. The present study evaluates the effects of various DIR and DNR conditions (both separately and in combination) on listening comfort among hearing aid users.Methods In 18 participants who received hearing aid fitting services from the Rehabilitation School of Shahid Beheshti University of Medical Sciences regularly, we applied acceptable noise level (ANL) as our subjective measure of listening comfort. We evaluated both of these under six different hearing aid conditions: omnidirectional-baseline, omnidirectional-broadband DNR, omnidirectional-multichannel DNR, directional, directional-broadband DNR, and directional-multichannel DNR.Results The ANL results ranged from −3 dB to 14 dB in all conditions. The results show, among all conditions, both the omnidirectional-baseline condition and the omnidirectional-broadband DNR condition are the worst conditions for listening in noise. The DIR always reduces the amount of noise that patients received during testing. The DNR algorithm does not improve listening in noise significantly when compared with the DIR algorithms. Although both DNR and DIR algorithms yielded a lower ANL, the DIR algorithm was more effective than the DNR.Conclusion The DIR and DNR technologies provide listening comfort in the presence of noise. Thus, user benefit depends on how the digital signal processing settings inside the hearing aid are adjusted.