Interrelationship between Speechreading and Use of Residual Hearing : Relationship between Reception of Syllable and Word and its Individuality

Abstract

Syllable articulation score and word intelligibility score by visual, auditory and both visual and auditory reception were measured for 13 hearing-im-pared children (Table 1) utilizing a monocrome TV recorder and monitor, and the relationship between hearing loss and effect of residual hearing upon speechreading and its individual characteristics were examined. Articulation scores of vowels, consonants and syllables by both visual and auditory reception (Fig. 1) and by only auditory reception (Fig. 3) decreased with the increase of the hearing loss, while those by only visual reception (Fig. 2) showed individual difference in the ability of speechreading. The effect of residual hearing upon speechreading of syllables, vowels and consonants inversely related to the hearing loss, but the effect showed a significant individuality (Fig. 4). Correlation coefficients among syllable, vowel and consonant articulation scores (Table 2) indicate that the ability of identifying consonants was closely related to that of syllables in Japanese. The individual characteristics of identification of vowels and consonants was analyzed, classifying the confusion matrices among vowels by visual reception (Table 3) and by auditory reception (Table 4), and the confusion matrices among consonants by visual reception (Table 5) and by auditory reception (Table 6). The relationship between hearing loss and word intelligibility scores by both visual and auditory reception (Fig. 5), by only visual reception (Fig. 6) and by only auditory reception (Fig. 7), and the relationship between hearing loss and effect of residual hearing upon speechreading of words (Fig. 8) showed a similar tendency to those of the syllables. The high correlation coefficients between syllable articulation score and the word intelligibility score (Table 7) and the high rate of correct answer for number of moras in the word (Table 8) suggests the fact that the abilities of identification of syllables and words are directly related to each other. The other intelligibility score, however, was affected by the easiness of the word as well as the number of homophenous words. Based on the results (Table 11), the most effective methods of training speechreading and use of residual hearing for each subject were discussed.