We want to thank Dr. Min Jung Kim for her suggestions on the scoring systems of word test and nonword repetition test and her comments on drafts of this manuscript. Objectives: This study aims to investigate developmental patterns of nonword repetition scores in 3-to 5-year-old typically developing children and examine whether and to what extent nonword repetition scores are related to age, vocabulary and articulatory skills. Methods: A total of 141 children (3-year age group, 37; 4-year age group, 52; 5-year age group, 52) participated in this study. Nonword repetition, articulation, and receptive and expressive vocabulary tests were administrated. Nonword repetition scores, word length and phoneme scores of the word test from Children Articulation and Phonology Profile, percentage of consonants correct from the Assessment of Phonology and Articulation for Children, and raw scores from Receptive & Expressive Vocabulary Test (REVT) were obtained. Results: Five-year-old children showed significantly higher nonword repetition scores than 3-and 4-year-old children. No significant difference existed between 3-and 4-year-old children. The results showed that nonword repetition scores were positively related to word length and phoneme scores of the word test and the raw scores of REVT. The regression analysis showed that word length scores and raw scores of the receptive vocabulary test significantly predict nonword repetition scores. Conclusion: This study suggests that nonword repetition performance reflect articulation skills and receptive vocabulary. The results support the clinical usefulness of nonword repetition task for screening children who may be at risk for speech and language disorders.

There are bi-directional links between phonological and lexical development in early language acquisition. This study analyzed phonological characteristics of words which 12-to 30-month-old children produced as recorded by parent reports, as well as early lexicons in Korean version MacArthur-Bates Communicative Development Inventories (K M-B CDI). Methods: The frequency of phonemes and word structures in all the words in the K M-B CDI were analyzed. The K M-B CDI was administrated to parents of 193 children. The groups were divided into the three age groups: 12-17 months, 18-23 months, and 24-30 months. Word lists acquired by 50% to 75% of children in the three age groups were phonemically transcribed and then the frequency of phonemes, consonants types in the initial position, and word structures were analyzed for each age group. Results: The most common word shapes in the K M-B CDI were CVCV and CVC, and were either disyllables or monosyllables. The most common phonemes of words in the K M-B CDI were /l, k, n, a, i/. Seventy-five percent of children aged 12-17 months produced only words with /m/ and /p*/, which start with either a vowel or nasal. The two groups below 24 months produced the VCV words shape most frequently. As children expand their expressive vocabulary with age, the number of phoneme types produced, the percentage of words starting with stops, and the word shape inventory increased. Conclusion: This study showed the phonological characteristics of early lexicon in Korean-acquiring children, which have implications in selecting target words for intervention considering both early phonological and lexical development.

Objectives:Of the various types of vocalization produced by children early on, canonical babbling is an important milestone that shows a high correlation with later speech-language development. This study aimed to investigate the development of canonical babbling from 0-6 months to 18-20 months and check the number of expressive words at 18-20 months. Also, we tracked the developmental changes of the canonical babbling from 0-20 months to confirm the onset and developmental process of canonical babbling in Korean-acquiring infants. Methods: The Language ENvironment Analysis system collected vocalization data produced by children during the day in a natural environment for 22 children recruited longitudinally and 59 children recruited cross-sectionally. Twenty 5-minute recorded vocalization data with the highest child vocalization rate were selected for each child, and the canonical babbling ratio was measured based on auditory perception analysis. Results: The results from the longitudinal and cross-sectional study showed that the canonical babbling ratio increased significantly after 7-8 months. Of the 22 children in the longitudinal study, 7 children produced less than .15 of the canonical babbling rate at 9-11 months of age, indicating that they had not entered the canonical babbling stage by then. Three of them represented less than the 10%ile in the Korean version of the MacArthur-Bates communication development assessment at 18-20 months of age. Conclusion: This study examined the development of canonical babbling from 0-6 months to 18-20 months. This is the first effort to present the development process and onset of the canonical babbling in Korean-learning children. 아동들은 의미 있는 낱말을 산출하기 전까지 다양한 유형의 발 성을 통해 의사소통 의도나 신체적 욕구를 표현한다. Oller (2000) 는 아동들이 초기에 산출하는 다양한 발성을 트림, 딸꾹질 같은 생 리적 발성과 말 같은 발성(speech-like vocalizations)으로 구분하였 다. 말 같은 발성은 생리적 발성이나 웃음, 울음소리와 달리 이후 점 차 말과 언어로 발달된다고 하여 원시발성(protophones)으로 지칭 하였다. 아동들이 제일 처음 산출하는 원시발성은 불완전한 성대 의 움직임으로 인해 완전히 공명되지 못한 채 산출되는 준 모음 (quasi-vowels)이며, 이후 성대가 점차 발달하여 정상적인 성대 진 동을 통해 완전히 공명된 모음(vowels)을 산출할 수 있게 된다. 또 한 입술, 턱, 혀 등의 조음기관의 움직임을 통해 자음 같은 소리(closant)를 포함하는 경계선 옹알이(marginal babbling)를 산출할 수 있게 된다. 경계선 옹알이는 느린 조음기관 개폐 움직임으로 인해 자음 같은 소리와 모음 사이의 포먼트 전이(formant transition) 구 간이 대략 120 ms 이상으로 길어 지각이 가능한 것이 특징이다. 이 후 아동은 조음기관의 움직임이 완전해지고 빨라지게 되면서 자음 과 모음이 사이의 포먼트 전이 구간이 짧은 음절성 옹알이(canonical babbling)를 산출할 수 있게 된다(Lee, Jhang, Relyea, Chen, & Oller, 2018).

No abstract

Objectives: Two distinctive characteristics of late talking children are reduced vocabulary size and delayed phonological skills. Few studies describe the phonological development status of late talking children by considering the Korean speech sound system. This study investigates the phonological development characteristics of 18 to 30-month-old late talking children as compared with typically developing children. Methods: The participants included 19 late talking children and 19 typically developing children. To investigate their phonological developments in more detail, each group was divided into two age groups who were 18-23 months and 24-30 months of age, respectively. Based on their 30-minute spontaneous speech samples, we examined the number of total utterances, number of different words, eojeol structure types, vocalization levels, consonant production ratio, and frequency ratio of consonants based on the place and manner of articulation. Results: Late talking children, as compared to typically developing children, showed fewer number of utterances and expressive vocabularies, lower vocalization levels, fewer number of consonant inventory and eojeol structure types. Regarding consonant types, typically developing children showed diverse speech production from the frontal and posterior parts of oral cavity whereas late talking children showed higher production of frontal sounds. The 24 to 30-month-old late talking children compared with 18 to 23-month-old late talking children displayed significantly higher performances in vocalization levels, palatal affricate sounds and the number of different eojeol structure types. Conclusion: These findings imply that we should examine their limited articulation and phonological abilities as well as the expressive vocabularies in late talking children in order to identify the children who need early speech-language interventions.