• Phonetics and Speech Sciences
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• v.15 no.3
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• pp.45-52
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• 2023

Previous studies have established a role for cognitive differences in explaining variability in speech processing across individuals. In the case of perceptual cue weighting in the context of a sound change, studies have produced conflicting results regarding the relationship between executive function and the use of redundant cues. The current study aimed to explore this relationship in acoustic cue weighting during speech production. Forty-one Korean-speaking children read a list of stop-initial words and completed two tests that assess executive function, i.e., Dimensional Change Card Sorting (DCCS) and digit n-back. Voice onset time (VOT) and fundamental frequency (F0) were measured in each word, and analyses were carried out to determine the extent to which children's executive function predicted their use of both informative and less informative cues to the three pairs comprising the Korean three-way stop laryngeal contrast. No evidence was found for a relationship between cognitive ability and acoustic cue weighting in production, which is at odds with previous, albeit conflicting, results for speech perception. While this result may be due to the lack of task demands in the production task used here, it nevertheless expands the empirical ground upon which future work in this area may proceed.

• Speech Sciences
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• v.15 no.3
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• pp.103-116
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• 2008

Cerebral palsy children represent abnormal vocalization pattern caused by respiration problem and paralyzed oral motor muscle that are the basics of speech production. Thus, this study examined the effect of respiration and articulator training programs on the basic ability of speech production in CP children. The subjects of this study were 4 children with 3 of spastic CP and 1 of ataxia CP. The respiration and articulator program was conducted in 30 sessions for 30 minutes each. Pre-test was administered twice before the program, ongoing test was administered every 5 session during the period of experiment, and post-test was administered twice. The program included speech production such as respiration training, lips, jaw, cheek, and tongue exercise, and velopharyngeal training, and related articulator training. The following results were obtained. First, all subject children were less than 5 seconds in maximum phonation time before the experiment and 2 were improved by more than 4$\sim$5 seconds during the experiment, but 2 had relatively low rising width. Second, while children with less than 30dB before the experiment became bigger in strength during the experiment, children with more than 35dB before the experiment showed a minor change. Subject child 4 had lower vocal strength in the post-test period. Finally, although each subject had individual difference in syllable diadochokinetic ability, the function was improved and the number of repetition in one respiration was also increased.

• Speech Sciences
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• v.13 no.1
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• pp.95-105
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• 2006

The primary goal of therapeutic intervention in dysarthric speakers is to increase the speech intelligibility. Decision of critical features to increase the intelligibility is very important in speech therapy. The purpose of this study is to know the effects of pitch increasing training (PIT) on speech of a subject with Parkinson's disease (PD). The PIT program is focused on increasing pitch while a vowel is sustained with the same loudness. The loudness level is somewhat higher than that of the habitual loudness. A 67-year-old female with PD participated in the study. Speech therapy was conducted for 4 sessions (200 minutes) for one week. Before and after the treatment, acoustic, perceptual and speech naturalness evaluation was peformed for data analysis. Speech and voice satisfaction index (SVSI) was obtained after the treatment. Results showed Improvements in voice quality and speech naturalness. In addition, the patient's satisfaction ratings (SVSI) indicated a positive relationship between improved speech production and their (the patient and care-givers) satisfaction.

• Phonetics and Speech Sciences
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• v.15 no.1
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• pp.47-54
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• 2023

This study attempted to test the hypothesis that Korean evaluators can score L2 speech appropriately, even when speech rate features are unavailable. Two perception experiments-preliminary and main-were conducted sequentially. The purpose of the preliminary experiment was to categorize English-as-a-foreign-language (EFL) speakers into two groups-advanced learners and lower-level learners-based on the proficiency scores given by five human raters. In the main experiment, a set of stimuli was prepared such that the speech rate of all data tokens was modified to have a uniform speech rate. Ten human evaluators were asked to score the stimulus tokens on a 5-point scale. These scores were statistically analyzed to determine whether there was a significant difference in utterance production between the two groups. The results of the preliminary experiment confirm that higher-proficiency learners speak faster than lower-proficiency learners. The results of the main experiment indicate that under controlled speech-rate conditions, human raters can appropriately assess learner proficiency, probably thanks to the linguistic features that the raters considered during the evaluation process.

• Phonetics and Speech Sciences
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• v.11 no.3
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• pp.1-7
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• 2019

Korean (L1)-English (L2) bilingual adults' and children's production of Korean and English stops was examined to determine the age effects and L2 experience on the development of L1 and L2 stop contrasts. Four groups of Seoul Korean speakers (experienced and inexperienced adult and child groups) and two groups of age-matched native English speakers participated. The overall results of voice onset time (VOT) and fundamental frequency (F0) of phrase-initial stops in Korean and word-intial stops in English showed a delay in the acquisition of L1 due to the dominant exposure to L2. Significantly longer VOT and lower F0 for aspirated stops as well as high temporal variability across repetitions of lenis stops were interpreted to indicate a strong effect of English on Korean stop contrasts for bilingual children. That is, the heavy use of VOT for Korean stop contrasts shows bilingual children's attention to the acoustic cue that are primarily employed in the dominant L2. Furthermore, inexperienced children, but not adults, were shown to create new L2 categories that are distinctive from the L1 within 6 months of L2 experience, suggesting greater independence between the two phonological systems. The implications of bilinguals' age at the time of testing to the degree and direction of L1-L2 interaction are further discussed.

• Phonetics and Speech Sciences
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• v.9 no.4
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• pp.123-128
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• 2017

This study aims to compare the performance of syllable identification task according to auditory and visual stimuli presentation methods and syllable position. Twenty-two typically developing children (age 4-6) participated in the study. Three-syllable words were used to identify the first syllable and the final syllable in each word with auditory and visual stimuli. For the auditory stimuli presentation, the researcher presented the test word only with oral speech. For the visual stimuli presentation, the test words were presented as a picture, and asked each child to choose appropriate pictures for the task. The results showed that when tasks were presented visually, the performances of phonological awareness were significantly higher than in presenting with auditory stimuli. Also, the performances of the first syllable identification were significantly higher than those of the last syllable identification. When phonological awareness task are presented by auditory stimuli, it is necessary to go through all the steps of the speech production process. Therefore, the phonological awareness performance by auditory stimuli may be low due to the weakness of the other stages in the speech production process. When phonological awareness tasks are presented using visual picture stimuli, it can be performed directly at the phonological representation stage without going through the peripheral auditory processing, phonological recognition, and motor programming. This study suggests that phonological awareness skills can be different depending on the methods of stimulus presentation and syllable position of the tasks. The comparison of performances between visual and auditory stimulus tasks will help identify where children may show weakness and vulnerability in speech production process.

• Phonetics and Speech Sciences
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• v.4 no.3
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• pp.129-136
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• 2012

Korean alveolar fricatives are late-developing speech sounds. Most previous research on phonemes used individual words or pseudo words to produce sounds, but word-level phonological analysis does not always reflect a child's practical articulation ability. Also, there has been limited research on articulation development looking at speech production by grammatical morphemes despite its importance in Korean language. Therefore, this research examines the articulation development and phonological patterns of the /s/ phoneme in terms of morphological types produced in children's spontaneous conversational speech. The subjects were twenty-two typically developing 3- and 4-year-old Koreans. All children showed normal levels in three screening tests: hearing, vocabulary, and articulation. Spontaneous conversational samples were recorded at the children's homes. The results are as follows. The error rates decreased with increasing age in all morphological contexts. Also, error percentages within an age group were significantly lower in lexical morphemes than in grammatical morphemes. The stopping of fricative sounds was the main error pattern in all morphological contexts and reduced as age increased. This research shows that articulation performance can differ significantly by morphological contexts. The present study provides data that can be used to identify the difficult context for articulatory evaluation and therapy of alveolar fricative sounds.

• Cross-Cultural Studies
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• v.28
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• pp.115-139
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• 2012

Interval or duration of segments, syllables, words and phrases is an important acoustic feature which influences the naturalness of speech. A number of cross-sectional studies regarding acoustic characteristics of children's speech development found that intervals of segments, syllables, words and phrases tend to change with the growing age. One hypothesis assumed that decreases in intervals would be greater when children were younger and smaller decreases in intervals when older (Thelen,1991), it has been supported by quite a number of researches on the basis of cross-sectional studies (Tingley & Allen,1975; Kent & Forner,1980; Chermak & Schneiderman, 1986), but the other hypothesis predicted that decreases in intervals would be smaller when children were younger and greater decreases in intervals when older (Smith, Kenney & Hussain, 1996). Researchers seem to come up with conflicting postulations and inconsistent results about the change trends concerning intervals of segments, syllables, words and phrases, leaving it as an issue unresolved. Most acoustic investigations of children's speech production have been conducted via cross-sectional designs, which involves studying several groups of children. So far, there are only a few longitudinal studies. This issue needs more longitudinal investigations; moreover, the acoustic measures of the intervals of child speech are hardly available. All former studies focus on word stages excluding the babbling stages especially the canonical babbling stage, but we need to find out when concrete changes of intervals begin to occur and what causes the changes. Therefore, we conducted an acoustic study of interval characteristics of segments and words concerning Canonical Babble ( CB) and early speech in an infant aged from 0;9 to 2;4 acquiring Mandarin Chinese. The current research addresses the following two questions: 1. Whether decreases in interval would be greater when children were younger and smaller when they were older or vice versa? 2. Whether the child speech concerning the acoustic features of interval drifts in the direction of the language they are exposed to? The female infant whose L1 was Southern Mandarin living in Changsha was audio- and video-taped at her home for about one hour almost on a weekly basis during her age range from 0;9 to 2;4 under natural observation by us investigators. The recordings were digitized. Parts of the digitized material were labeled. All the repetitions were excluded. The utterances were extracted from 44 sessions ranging from 30 minutes to one hour. The utterances were divided into segments as well as syllable-sized units. Age stages are 0;9-1;0,1;1-1;5, 1;6-2;0, 2;1-2;4. The subject was a monolingual normal child from parents with a good education. The infant was audio-and video-taped in her home almost every week. The data were digitized, segments and syllables from 44 sessions spanning the transition from babble to speech were transcribed in narrow IPA and coded for analysis. Babble was coded from age 0;9-1;0, and words were coded from 1;0 to 2;4, the data has been checked by two professionally trained persons who majored in phonetics. The present investigation is a longitudinal analysis of some temporal characteristics of the child speech during the age periods of 0;9-1;0, 1;1-1;5, 1;6-2;0, 2;1-2;4. The answer to Research Question 1 is that our results are in agreement with neither of the hypotheses. One hypothesis assumed that decreases in intervals would be greater when children were younger and smaller decreases in intervals when older (Thelen,1991); but the other hypothesis predicted that decreases in intervals would be smaller when children were younger and greater decreases in intervals when older (Smith, Kenney & Hussain, 1996). On the whole, there is a tendency of decrease in segmental and syllabic duration with the growing age, but the changes are not drastic and abrupt. For example, /a/ after /k/ in Table 1 has greater decrease during 1;1-1;5, while /a/ after /p/, /t/ and /w/ has greater decrease during 2;1-2;4. /ka/ has greater decrease during 1;1-1;5, while /ta/ and /na/ has greater decrease during 2;1-2;4.Across the age periods, interval change experiences lots of fluctuation all the time. The answer to Research Question 2 is yes. Babbling stage is a period in which the children's acoustic features of intervals of segments, syllables, words and phrases is shifted in the direction of the language to be learned, babbling and children's speech emergence is greatly influenced by ambient language. The phonetic changes in terms of duration would go on until as late as 10-12 years of age before reaching adult-like levels. Definitely, with the increase of exposure to ambient language, the variation would be less and less until they attain the adult-like competence. Via the analysis of the SPSS 15.0, the decrease of segmental and syllabic intervals across the four age periods proves to be of no significant difference (p>0.05). It means that the change of segmental and syllabic intervals is continuous. It reveals that the process of child speech development is gradual and cumulative.

• Clinical and Experimental Pediatrics
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• v.57 no.7
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• pp.323-328
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• 2014

Purpose: Adenoid hypertrophy is a physical alteration that may affect speech, and a speech disorder can have other negative effects on a child's life. Airway obstruction leads to constricted oral breathing and causes postural alterations of several oro-facial structures, including the mouth, tongue, and hyoid bone. The postural modifications may affect several aspects of speech production. Methods: In this study, we compared articulation errors in 19 children with adenoid hypertrophy (subject group) to those of 33 children with functional articulation disorders independent of anatomical problems (control group). Results: The mean age of the subject group was significantly higher (P=0.016). Substitution was more frequent in the subject group (P=0.003; odds ratio [OR], 1.80; 95% confidence interval [CI], 1.23- 2.62), while omission was less frequent (P<0.001; OR, 0.43; 95% CI, 0.27-0.67). Articulation errors were significantly less frequent in the palatal affricative in the subject group (P=0.047; OR, 0.25; 95% CI, 0.07-0.92). The number of articulation errors in other consonants was not different between the two groups. Nasalization and aspiration were significantly more frequent in the subject group (P=0.007 and 0.014; OR, 14.77 and 0.014; 95% CI, [1.62-135.04] and NA, respectively). Otherwise, there were no differences between the two groups. Conclusion: We identified the characteristics of articulation errors in children with adenoid hypertrophy, but our data did not show the relationship between adenoid hypertrophy and oral motor function that has been observed in previous studies. The association between adenoid hypertrophy and oral motor function remains doubtful.

• Phonetics and Speech Sciences
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• v.13 no.2
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• pp.77-90
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• 2021

This study is to develop a Korean version of nonword intervention by modifying and supplementing a Rapid syllable transition treatment (ReST) and to determine its effect by applying it to children with CAS. Ultimately, the purpose of this study is to investigate whether nonword interventions are effective for nonword production ability and generalization of real words. Single-subject research using the ABA design was performed for a child aged five years and six months with diagnostic features of CAS. The nonwords used in the interventions were made suitable for the individual child. The intervention was provided in one-hour sessions, twice a week for six weeks. In all cases, performance of the treated three-syllable nonwords improved, and untreated three-syllable words, four-syllable words, and nonwords showed a generalization effect. However, the generalization of treatment effects to words was smaller than for nonwords. The nonword intervention was effective in improving the subject's speech motor programming skills. As a result, transition errors due to impaired speech motor programming were greatly reduced, and the ability to produce untreated nonwords was greatly increased. However, there was a limit to the full improvement of strongly habitable word errors, which would be expected if a more intensive and repetitive intervention schedule was provided.