Browsing by Author "Yoo, Hyunjoo"

Now showing 1 - 11 of 11
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    Acoustic Correlates and Adult Perceptions of Distress in Infant Speech-Like Vocalizations and Cries
    (Frontiers, 2019) Yoo, Hyunjoo; Buder, Eugene H.; Bowman, Dale D.; Bidelman, Gavin M.; Oller, D. Kimbrough; University of Alabama Tuscaloosa; University of Memphis; University of Tennessee Health Science Center
    Prior research has not evaluated acoustic features contributing to perception of human infant vocal distress or lack thereof on a continuum. The present research evaluates perception of infant vocalizations along a continuum ranging from the most prototypical intensely distressful cry sounds ("wails") to the most prototypical of infant sounds that typically express no distress (non-distress "vocants"). Wails are deemed little if at all related to speech while vocants are taken to be clear precursors to speech. We selected prototypical exemplars of utterances representing the whole continuum from 0 and 1 month-olds. In this initial study of the continuum, our goals are to determine (1) listener agreement on level of vocal distress across the continuum, (2) acoustic parameters predicting ratings of distress, (3) the extent to which individual listeners maintain or change their acoustic criteria for distress judgments across the study, (4) the extent to which different listeners use similar or different acoustic criteria to make judgments, and (5) the role of short-term experience among the listeners in judgments of infant vocalization distress. Results indicated that (1) both inter-rater and intra-rater listener agreement on degree of vocal distress was high, (2) the best predictors of vocal distress were number of vibratory regimes within utterances, utterance duration, spectral ratio (spectral concentration) in vibratory regimes within utterances, and mean pitch, (3) individual listeners significantly modified their acoustic criteria for distress judgments across the 10 trial blocks, (4) different listeners, while showing overall similarities in ratings of the 42 stimuli, also showed significant differences in acoustic criteria used in assigning the ratings of vocal distress, and (5) listeners who were both experienced and inexperienced in infant vocalizations coding showed high agreement in rating level of distress, but differed in the extent to which they relied on the different acoustic cues in making the ratings. The study provides clearer characterization of vocal distress expression in infants based on acoustic parameters and a new perspective on active adult perception of infant vocalizations. The results also highlight the importance of vibratory regime segmentation and analysis in acoustically based research on infant vocalizations and their perception.
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    Cross-linguistic comparison of utterance shapes in Korean- and English-learning children: An ambient language effect
    (Elsevier, 2021) Ha, Seunghee; Johnson, Cynthia J.; Oller, Kimbrough D.; Yoo, Hyunjoo; Hallym University; University of Illinois Urbana-Champaign; University of Memphis; University of Alabama Tuscaloosa
    This study compared vocal development in Koreanand English-learning infants and examined ambient-language effects focusing on predominant utterance shapes. Vocalization samples were obtained from 14 Korean-learning children and 14 English-learning children, who ranged in age from 9 to 21 months, in monolingual environments using day-long audio recordings. The analyzers, who were blind to participants' demographic information, identified utterance shapes to determine functional vocal repertoires through naturalistic listening simulating the caregiver's natural mode of listening. The results showed no cross-linguistic differences in the amount of vocal output or the proportion of canonical syllables. However, the infants from the two language backgrounds showed differences regarding the predominant canonical utterance shapes. The percentage of VCV utterances in Korean-learning children was higher than in English-learning children while CV syllables predominated in the English-learning children. We speculate that the difference between the predominant utterance shapes of Koreanand English-learning children could be associated with differences in early lexical items typically acquired in the two language groups.
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    Early intervention effects on gesture use in young children with ASD: a national query of SLPs
    (University of Alabama Libraries, 2020) Miller, Julia; Barber, Angela; University of Alabama Tuscaloosa
    Gesture development, use, and repertoire differ in young children with ASD compared to those with typical development (Manwaring et al., 2018 and Watson et al., 2013). Gestures play a fundamental role in social interaction and therefore are often an important intervention outcome in early ASD interventions. However, which interventions are most often used and which of those are most effective remains unclear. Naturalistic Developmental Behavioral Interventions (Schreibman et al., 2015) most frequently incorporate gestures into their teaching targets and outcomes though gestures are often measured within a broader scope of social interaction. Therefore, even within the scope of NDBIs, techniques used to teach gestures, how gestures are measured, and how gestures are prioritized vary greatly and are often not reported distinctively. Further, SLPs are the primary interventionists for improving gestures and social communication though very little is understood regarding how SLPs address gestures in early interventions. Therefore, the purpose of this study was to survey practicing SLPs to determine which methods are most frequently used to teach gestures to young children with ASD and which of those methods are considered effective. Overall, SLPs reported a large range of experience in their training, methods used, and perspectives of efficacy as they relate to teaching deictic gestures.
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    Infant boys are more vocal than infant girls
    (Cell Press, 2020) Oller, D. Kimbrough; Griebel, Ulrike; Bowman, Dale D.; Bene, Edina; Long, Helen L.; Yoo, Hyunjoo; Ramsay, Gordon; University of Memphis; University of Alabama Tuscaloosa; Children's Healthcare of Atlanta (CHOA); Emory University
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    The Origin of Protoconversation: An Examination of Caregiver Responses to Cry and Speech-Like Vocalizations
    (Frontiers, 2018) Yoo, Hyunjoo; Bowman, Dale A.; Oller, D. Kimbrough; University of Alabama Tuscaloosa; University of Memphis
    Turn-taking is a universal and fundamental feature of human vocal communication. Through protoconversation, caregivers play a key role for infants in helping them learn the turn-taking system. Infants produce both speech-like vocalizations (i.e., protophones) and cries from birth. Prior research has shown that caregivers take turns with infant protophones. However, no prior research has investigated the timing of caregiver responses to cries. The present work is the first to systematically investigate different temporal patterns of caregiver responses to protophones and to cries. Results showed that, even in infants' first 3 months of life, caregivers were more likely to take turns with protophones and to overlap with cries. The study provides evidence that caregivers are intuitively aware that protophones and cries are functionally different: protophones are treated as precursors to speech, whereas cries are treated as expressions of distress.
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    The perception of regional dialect in the state of Alabama
    (University of Alabama Libraries, 2020) Sizemore, McKenzie D.; Buhr, Anthony; University of Alabama Tuscaloosa
    The purpose of this study was to evaluate how accurate people are in perceiving the dialects in the state of Alabama. This study included 50 speakers, each of whom produced a portion of the “Arthur the Rat” passage, which was then rated by 60 listeners according to whether the speaker was from the state of Alabama or not and whether that person was from an urban or rural area. Overall results showed that people from both inside and outside of Alabama were significantly better than chance at determining if a person is from Alabama. However, when compared to participants from outside of Alabama, participants from Alabama are significantly better at determining if a person was from an urban or rural area. Results suggest that people from the state of Alabama are more attuned to the dialectal differences within the state of Alabama compared to those who are not born in the state of Alabama.
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    Preterm and full term infant vocalization and the origin of language
    (Nature Portfolio, 2019) Oller, D. Kimbrough; Caskey, Melinda; Yoo, Hyunjoo; Bene, Edina R.; Jhang, Yuna; Lee, Chia-Cheng; Bowman, Dale D.; Long, Helen L.; Buder, Eugene H.; Vohr, Betty; University of Memphis; Kaiser Permanente; University of Alabama Tuscaloosa; Chung Shan Medical University; Portland State University; Women & Infants Hospital Rhode Island; Brown University
    How did vocal language originate? Before trying to determine how referential vocabulary or syntax may have arisen, it is critical to explain how ancient hominins began to produce vocalization flexibly, without binding to emotions or functions. A crucial factor in the vocal communicative split of hominins from the ape background may thus have been copious, functionally flexible vocalization, starting in infancy and continuing throughout life, long before there were more advanced linguistic features such as referential vocabulary. 2-3 month-old modern human infants produce "protophones", including at least three types of functionally flexible non-cry precursors to speech rarely reported in other ape infants. But how early in life do protophones actually appear? We report that the most common protophone types emerge abundantly as early as vocalization can be observed in infancy, in preterm infants still in neonatal intensive care. Contrary to the expectation that cries are the predominant vocalizations of infancy, our all-day recordings showed that protophones occurred far more frequently than cries in both preterm and full-term infants. Protophones were not limited to interactive circumstances, but also occurred at high rates when infants were alone, indicating an endogenous inclination to vocalize exploratorily, perhaps the most fundamental capacity underlying vocal language.
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    Sex differences in infant vocalization and the origin of language
    (Cell Press, 2023) Oller, D. Kimbrough; Gilkerson, Jill; Richards, Jeffrey A.; Hannon, Steve; Griebel, Ulrike; Bowman, Dale D.; Brown, Jane A.; Yoo, Hyunjoo; Warren, Steven F.; University of Memphis; University of Alabama Tuscaloosa; University of Kansas
    Seeking to discern the earliest sex differences in language-related activities, our focus is vocal activity in the first two years of life, following up on recent research that unexpectedly showed boys produced significantly more speech-like vocalizations (protophones) than girls during the first year of life.We now bring a much larger body of data to bear on the comparison of early sex differences in vocali-zation, data based on automated analysis of all-day recordings of infants in their homes. The new evidence, like that of the prior study, also suggests boys produce more protophones than girls in the first year and offers additional basis for informed speculation about biological reasons for these differences. More broadly, the work offers a basis for informed speculations about foundations of language that we propose to have evolved in our distant hominin ancestors, foun-dations also required in early vocal development of modern human infants.
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    Social and endogenous infant vocalizations
    (PLOS, 2020) Long, Helen L.; Bowman, Dale D.; Yoo, Hyunjoo; Burkhardt-Reed, Megan M.; Bene, Edina R.; Oller, D. Kimbrough; University of Memphis; University of Alabama Tuscaloosa
    Research on infant vocal development has provided notable insights into vocal interaction with caregivers, elucidating growth in foundations for language through parental elicitation and reaction to vocalizations. A role for infant vocalizations produced endogenously, potentially providing raw material for interaction and a basis for growth in the vocal capacity itself, has received less attention. We report that in laboratory recordings of infants and their parents, the bulk of infant speech-like vocalizations, or "protophones", were directed toward no one and instead appeared to be generated endogenously, mostly in exploration of vocal abilities. The tendency to predominantly produce protophones without directing them to others occurred both during periods when parents were instructed to interact with their infantsandduring periods when parents were occupied with an interviewer, with the infants in the room. The results emphasize the infant as an agent in vocal learning, even when not interacting socially and suggest an enhanced perspective on foundations for vocal language.
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    The variability of stuttering and influential factors
    (University of Alabama Libraries, 2020) Sherbert, Kayla Jane; Buhr, Anthony; University of Alabama Tuscaloosa
    Stuttering is a disorder of speech fluency that is not well understood, in part due to its variable nature. Although a number of factors have been found to contribute to this variability, previous research has often been retrospective or experimental. In this study, forty-one college students completed a survey three times a day for at least two weeks. Each participant evaluated their experiences regarding their own speech fluency, affective state, and willingness to approach. It was expected that affective state would be associated with speech fluency as well as willingness to approach. The main finding of the study was that dimensions of affect (i.e., arousal and mood) were significantly associated with speech fluency, particularly in the morning compared to the afternoon or evening. Results are interpreted to suggest that the positive relation between speech fluency and affect could be outcomes of a common physiological state, a finding that could have important implications for fluency disorders such as stuttering.
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    Vowel production variation in college students based on social integration
    (University of Alabama Libraries, 2020) Chapman, Sarah Kristin; Reed, Paul E.; University of Alabama Tuscaloosa
    Exemplar theory represents the encoding of individual experiences as a collection of episodic memories known as exemplars, which form “exemplar clouds” (Drager & Kirtley, 2016). Originally used to model phonetic classification in perception, the exemplar theory has been extended to speech production with evidence that the perception-production loop can cause shifts over time. While exemplars are considered robust and stable categories, Clopper (2014) suggested that shifts can occur when individuals move to an environment in which they are exposed to a high quantity of exemplars from different regional or social distributions. The present study investigated the following research question: Does involvement in highly structured social groups, such as Greek life, influence the variation of vowel productions in young adults? The overarching purpose of the study was to explore how immersion in new social groups leads to exemplar shifts in college students. The data from this study was collected from 30 in-state female students at The University of Alabama (15 Greek, 15 non-Greek) from a semi-structured interview, reading passages, and word list tasks. Results indicated a statistically significant difference in degree of monophthongization of /a͡ɪ/ based on Greek status. Specifically, participants in Greek organizations were significantly more diphthongal in reading passages and word list tasks, and the difference was trending towards significance for conversational tasks and all tasks combined. Thus, these results indicate that involvement in highly integrated groups such as Greek life may impact exemplar shifts in college students. Key words: sociophonetics, exemplars, production shift, social integration, monophthongization