初鹿 信一 東京医科大学, 医学部, 講師 (20211477)
KAWANO Atsushi Tokyo Medical College, Sch. of Med. Assistant, 医学部, 助手 (00224808)
HIRAIDE Fumihisa Tokyo Medical College, Sch. of Med. Professor, 医学部, 教授 (50010343)
|Budget Amount *help
¥6,600,000 (Direct Cost : ¥6,600,000)
Fiscal Year 1991 : ¥2,200,000 (Direct Cost : ¥2,200,000)
Fiscal Year 1990 : ¥4,400,000 (Direct Cost : ¥4,400,000)
As a first step, transition of electrode number was explored for consonants of /p, t, k, b, d, g, h, s, z. m, n, r. j. w/. The obtained transition patterns of the electrode number were compared with calculated patterns from the sonagranl This study revealed that coding of the speech procesor was reasonable for fricatives, semivowels and nasal consonants, but was not well for plosives.
The comparison of speech perception for original and processed speech sounds showed that the energy increase in consonant burst was effective, especially in fricatives and plosives.
Multiregression analysis of the information transmission ratio and the speech perception score of consonants revealed that nasal consonants and semivowels were high contributing consonants to the score in cochlear implant patients.
An animal experiment showed-that greater and steeper input-output curves were obtained in cats with a high survival rate of the spiral ganglion cells.
From these facts, it was concluded that more precise analyses for plosives and nasal consonants were necessary to improve the speech perception ability of cochlear implant patients.