The Analysis Of Speech Recognition Abilities Of Deafness Children Treated With Cochlear Implants Or Hearing Aids Under Different Noisy Condition

Objective: the difference of speech recognition score (SRS) of children treated with cochlear implantation(CI) or hearing aid (HA) in quiet and noisy environment were analyzed to help language rehabilitation.Materials and methods: the testing materials were made according to the standard published in Auditory Speech Evaluation Word List for the Rehabilitation of Deaf Children which was widely adopted by nationwide Deaf Children Rehabilitation system. The testing sounds were female reading voice including consonants, vowels, monosyllables, and short sentences. The background noise included the sound of train (0.5KHz), the sound of truck (1.0KHz), the sound of firecracker(2.0KHz), and dialogues between man and woman(3-4.0KHz). The main frequency span covered the speech frequency. The patients included 10 prelingual deaf children treated with multichannel artificial cochlea (CI group)and 12 deaf children treated with hearing aid(HA group). The etiologic factor, age, time of cochlear plantation (wearing hearing aid), communication mode, hearing level after the treatment, and language training condition were balanced in all patients. Patients suffered from dysgnosia and center hearing system disease were excluded. Open testing of SRS in quiet and noisy environment were carried out for all the patients whose SRS in quiet over 65%. The relative SRS in and between CI group and HA group were compared for significant difference in different noisy environment. The relative SRS= The SRS in noisy/ The SRS in quiet.Results: In different noisy environment, the difference of relative SRS between HA group and CI group was statistically significant(P<0.01); SRS in noisy environment was significantly lower than that in quiet environment in both groups (P<0.01); There was differences of SRS between different noise groups:train and truck ,truck and firecracker, firecracker and dialogue between man and woman but in HA group ,the difference between firecracker and dialogue groups is not statistically significant (P>0.05); in the same noisy environment SRS of HA group and CI group were significantly different(P<0.01); for CI group patients in quiet environments, the decreasing sequence of testing sounds according to SRS,were short sentences ,vowels ,consonants, monosyllable (P<0.01); while in noisy environments the average SRS of all testing sounds were obviously lower than that tested in quiet environment(P<0.01), and the decreasing sequence were vowels, consonants, monosyllable and short sentences (P<0.01).Conclusion : 1) For CI group patients in quiet environments , the decreasing sequence of testing sounds according to SRS, were short sentences,vowels,consonants,monosyllables; while in noisy environments short sentences became the last one. That shows that SRS of short sentences are most easily affected. 2) In the same noisy environment, SRS of CI group was higher than that of HA group. 3) In all the patients, SRS were different according to different noises, and the more similar the frequency of noise was to testing sounds, the lower SRS was detected.