A Longitudinal Study of Development of the Infant's Speech Sounds : 18 to 24 Months

Hong, Gyung-Hun; Sim, Hyun-Sub

ORIGINAL ARTICLE

Commun Sci Disord. 2002;7(2): 106-125.

Gyung-Hun Hong^` , and Hyun-Sub Sim^`

홍경훈(Gyung-Hun Hong)| 심현섭(Hyun-Sub Sim)

ABSTRACT

The current study aimed to (1) identify the phonetic inventory , the frequency ratios of consonant s, and the syllable type/ structure in the spontaneou s speech collected longitudinally from one Korean infant and (2) compare the findings with the data from adult s (Park, 2000). Data were collected every month during the age of 18 to 24 months . T he analy ses on the frequency of the initial con sonant in a syllable according to the manner of articulation showed that (1) plosives appeared most frequently ; nasals, affricates, fricatives and liquids followed in order acros s the observation periods, (2) as the age increased, the ratio of the plosives decreased gradually , but ratios of affricates, fricatives and liquids increased gradually . The analyses on the place of articulation showed that (1) dental sounds appeared most frequently at the early stage of observation and velar , bilabial, palatal, glottal sounds followed in order , but at the final stage the ratio of palatal sound was higher than the bilabial sounds . The analyses on the final consonant s showed that (1) liquids were produced most frequently and ratios of plosives and liquids increased gradually as the age increased, (2) the velar sounds appeared most frequently at the beginning, which was followed by bilabial sounds, and alveolar sounds. (3) the dental sounds increased gradually but became the most frequent sounds finally. The analy sis on syllable type/ structure revealed that the infant preferred CV type and open syllable. T he findings suggest that infant s speech sounds are getting closer to the adult speech.

Keywords: 말소리 발달 | 자음목록 | 자음 산출율