청각보상 전후 청각장애아동 음성의 음향학적 특성 비교 연구(1)

The Study about Acoustic Characteristics for Hearing Impaired before and after Wearing Hearing Aid and Cochlea Implants(1)

The purposes of this study were to examine the changes of acoustic characteristics of hearing impaired children's sound and speech before and after offering auditory feedback which used a hearing aid, and to find out the effects of auditory feedback on the changes. The participants were composed of 10 normal children and 10 children with a hearing aid on. The conditions for the selection of participants were limited to children with no physical handicaps including hearing impairment, children who lost hearing before language acquisition, children whose hearing loss was over 90 dB, and children who depended entirely on a hearing aid. Their age range was from 9 to 10 years old. In order to find out the changes of acoustic characteristics of hearing impaired children's sound made by auditory feedback, the study went through F1, F2, F2-F1 analyses in the sounds of /ah, 00, ih/ vowels through CSL, and compared them with a FO analysis in the first and second syllabus speeches. The mean differences of FO, F1, F2, F2-F1, before and after putting on a hearing aid and a cochlear implant, was verified by means of a paired t-test. Such analyses draw the following major conclusions: First, auditory feedback through the use of a hearing aid improves articulation problem in the sounds of /ah, 00, ih/ vowels created by hearing impaired children. That is, after the auditory feedback, the location of tongue was modified by putting lower or backward their tongue for /ah/ vowel, higher or more backward for /uh/ vowel, and higher or more forward for /ih/ vowel. Since this phenomenon is considered to improve the articulation of vowel problem through the modification of the location of tongue by offering auditory feedback, there can be direct correlations between auditory feedback and acoustic characteristics of sound. Second, auditory feedback through the use of a hearing aid improves articulation problem in the hearing impaired children's first and second syllabus speeches. That is, since the fact that the pitch gets lower means the improvement of articulation problem, there can be direct correlations between auditory feedback and acoustic characteristics of speech.