Evaluation Of Speech Rehabilitation Effect Of Hearing Devices Recipients Using Frequency Modulated System

1.Background and PurposeHearing impairment brings not only heavy burden to the family and the society,but also reduces quality of life seriously.What's more,it may produce negative effects on the physical and psychological development for children and teenagers.Actually,choosing hearing aid(HA)and cochlear implant(CI)to compensate or restore hearing are the main ways.Even using the best or the most appropriate hearing devices,the decrease of signal-to-noise(SNR)in the real world still limits the hearing and speech rehabilitation,influences their growth.The negative acoustic effects can be overcome for children and teenagers with hearing loss by the use of frequency-modulated(FM)systems,one of assistive listening system(ALS),which can improve SNR effectively by conveying and magnifying speech signal to hearing devices.However,the most researches on FM system focused on testing English-native listeners and evaluating the speech-recognition scores,thus ignoring the Chinese-native listeners and the assessment of subjective performance.As we know,Mandarin Chinese and English are very different languages,because Mandarin Chinese is a tonal language and English is not.It is necessary for further study.The goa l of this study is to evaluate the speech rehabilitation effects of FM system on the Chinese-native HA and CI listeners in daily lives and investigate the subjective improvement of listeners,verify the advantages of FM system.2.Method22 subjects participated in the study including 11 CIs and 11 HAs,ranging in age from 4 to 9 years,met the inclusion criteria in the text.All testing was conducted using custom mandarin speech perception(MSP)software as speech materials,which was developed at House Research Institute.Participants were tested in a total of 14 speech-recognition-in noise-test conditions,which included one no-FM and with-FM device conditions at the following signal levels: 65 d B SPL speech(at the location of the participant)in quiet and 65 d B SPL speech with competing noise at 50,55,60,65,70,75 d B SPL n oise levels.A repeated-measures analysis of variance with one between-participants variable of device condition and one within-participant variables of signal level was used to examine performance differences among devices,among speech recognition condit ions in quiet and in increasing levels of background noise.Post hoc analyses were conducted with the Bonferroni Test to examine more closely the significant differences detected among devices.3.Results1)In Experiments 1: for CIs,all of the FM system conditions outperformed the no-FM conditions in test situations with competing noise(all p<0.05),and the greater the intensity of the noise level the more FM advantages.In addition,the listeners performed more confident and quicker response with FM system conditions.In all conditions,performance became poorer as the competing noise level increased.2)In Experiments 2: use of FM resulted in better speech recognition and quicker response in noise for HAs at noise levels of 55,60,65,70,and 75 dB SPL,but n o significant differences were found across the quiet and noise levels of 50 dB SPL conditions.In all conditions,performance became poorer as the competing noise level increased.4.conclusionFM should be considered for use with persons with CIs or HAs to improve speech recognition in real world,promote to set the proper state of mind,help integrate them into society.