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Purpose: This study investigated the classification accuracy of a concentrated English narrative dynamic assessment (DA) for identifying language impairment (LI). Method: Forty-two Spanish-English bilingual kindergarten to third-grade children (10 LI and 32 with no LI) were administered two 25-min DA test-teach-test sessions. Pre- and posttest narrative retells were scored in real time. Using a structured intervention approach, examiners taught children missing story grammar elements and subordination. A posttest was administered using a parallel story. Results: Four classification predictors were analyzed: posttest scores, gain scores, modifiability ratings, and teaching duration. Discriminant function analysis indicated that an overall modifiability rating was the best classifier, with 100% sensitivity and 88% specificity after 1 DA session and 100% sensitivity and specificity after 2 sessions. Any 2 combinations of posttest scores, modifiability ratings, and teaching duration for just 1 session resulted in sensitivity and specificity rates over 90%. Receiver operating characteristic analyses were used to identify clinically usable cutoff points. Post hoc exploration indicated that similar results could be obtained after only one 5-10-min teaching cycle, potentially further abbreviating the DA process. Conclusion: Concentrated English narrative DA results in high classification accuracy for bilingual children with and without LI. This efficient version of DA is amenable to clinical use.

Purpose: This study investigated the classification accuracy of a concentrated English narrative dynamic assessment (DA) for identifying language impairment (LI). Method: Forty-two Spanish-English bilingual kindergarten to third-grade children (10 LI and 32 with no LI) were administered two 25-min DA test-teach-test sessions. Pre- and posttest narrative retells were scored in real time. Using a structured intervention approach, examiners taught children missing story grammar elements and subordination. A posttest was administered using a parallel story. Results: Four classification predictors were analyzed: posttest scores, gain scores, modifiability ratings, and teaching duration. Discriminant function analysis indicated that an overall modifiability rating was the best classifier, with 100% sensitivity and 88% specificity after 1 DA session and 100% sensitivity and specificity after 2 sessions. Any 2 combinations of posttest scores, modifiability ratings, and teaching duration for just 1 session resulted in sensitivity and specificity rates over 90%. Receiver operating characteristic analyses were used to identify clinically usable cutoff points. Post hoc exploration indicated that similar results could be obtained after only one 5-10-min teaching cycle, potentially further abbreviating the DA process. Conclusion: Concentrated English narrative DA results in high classification accuracy for bilingual children with and without LI. This efficient version of DA is amenable to clinical use., Children with language impairment (LI) must be identified to receive individualized educational support, including language intervention. Despite considerable evidence concerning the lack of sensitivity and specificity in the identification of [...]

An empirical gap exists in our understanding of the extent that mandibular kinematics modulate acoustic changes in natural babble productions of infants. Data were recorded from a normal developing 9-month-old infant. Mandibular position was tracked from the infant during vowel and canonical babble. Linear predictive coding analysis was used to track estimates of formant center-frequency for F1. For each sample, a correlation coefficient was computed between changes in jaw height and formant history for F1. A Mann-Whitney rank sum test reached significance for differences among coefficients for vowel and canonical babble. Coefficients for vowel babble productions were nearest to -1 with a median of r = -0.76, showing the strongest relationship between jaw position and formant history, while the median for canonical babble coefficients was r = -0.54, indicating greater contribution of the tongue and lips. This 9-month-old infant exhibited plasticity for coordinating the jaw, tongue and lips among babble types. (Contains 4 figures and 1 table.)

An empirical method for investigating differences in neural control of jaw movement across oromandibular behaviours is to compute the coherence function for electromyographic signals obtained from mandibular muscle groups. This procedure has been used with adults but not extended to children. This pilot study investigated if coherence analysis could reveal task-related differences in control for children by measuring mandibular electromyograms obtained from an infant and adult. Electromyographic signals were obtained from bilateral masseter and temporalis muscle groups during chewing and babble from a typically developing infant from 8-22 months, and chewing and speech were obtained from an adult. Coherence functions were computed. Measures obtained from the infant and adult exhibited a significant main effect for task, with peak coherence values within 20-60 Hz being significantly greater for chewing than vocalization. This pilot study suggests that coherence analysis of mandibular EMG is a sensitive measure for distinguishing task-related differences in neural organization for children. (Contains 2 tables and 5 figures.)

Purpose: The mandible is often portrayed as a primary structure of early babble production, but empiricists still need to specify (a) how mandibular motor control and kinematics vary among different types of multisyllabic babble, (b) whether chewing or jaw oscillation relies on a coordinative infrastructure that can be exploited for early types of multisyllables, and (c) whether the organization of motor control and associated kinematics varies across the nonspeech behaviors that are candidate motor stereotypies for speech. Method: Electromyographic signals were obtained from mandibular muscle groups, and associated kinematics were measured longitudinally from a typically developing infant from 9 to 22 months during jaw oscillation, chewing, and several types of early multisyllabic babble. Results: Measures of early motor control and mandibular kinematics for multisyllabic productions indicated task-dependent changes across syllable types and significant differences across babble and nonspeech behaviors. Differences in motor control were also observed across nonspeech behaviors. Conclusions: Motor control for babble appears to be influenced by the balanced interaction between developing motor and linguistic systems, such that variation in linguistic complexity systematically evinces changes in motor organization apparently to meet these demands. This same effect was noted among chewing and jaw oscillation; task-dependent changes in mandibular control were noted across behaviors.

Purpose: The ontogeny of mandibular control is important for understanding the general neurophysiologic development for speech and alimentary behaviors. Prior investigations suggest that mandibular control is organized distinctively across speech and nonspeech tasks in 15-month-olds and adults and that, with development, these extant forms of motor control primarily undergo refinement and rescaling. The present investigation was designed to evaluate whether these coordinative infrastructures for alimentary behaviors and speech are evident during the earliest period of their co-occurrence. Method: Electromyographic (EMG) signals were obtained from the mandibular muscle groups of 15 typically developing 9-month-old children during sucking, chewing, and speech. Results: Unlike prior investigations of 12- and 15-month-olds and adults, 9-month-olds' analyses of peak correlations among agonist and antagonist comparisons of mandibular EMG data revealed weak coupling during sucking, chewing, and babble; associated lag values for antagonist muscle groups indicated greater synchrony during alimentary behaviors and less synchrony during babble. Unlike the speech data of 15-month-olds, 9-month-olds exhibited consistent results across speech subtasks. Conclusion: These findings were consistent with previous results in which mandibular coordination across behaviors was more variable for younger age groups, whereas the essential organization of each behavior closely reflected that seen in older infants and adults.

Purpose: The mandible is often portrayed as a primary structure of early babble production, but empiricists still need to specify (a) how mandibular motor control and kinematics vary among different types of multisyllabic babble, (b) whether chewing or jaw oscillation relies on a coordinative infrastructure that can be exploited for early types of multisyllables, and (c) whether the organization of motor control and associated kinematics varies across the nonspeech behaviors that are candidate motor stereotypies for speech. Method: Electromyographic signals were obtained from mandibular muscle groups, and associated kinematics were measured longitudinally from a typically developing infant from 9 to 22 months during jaw oscillation, chewing, and several types of early multisyllabic babble. Results: Measures of early motor control and mandibular kinematics for multisyllabic productions indicated task-dependent changes across syllable types and significant differences across babble and nonspeech behaviors. Differences in motor control were also observed across nonspeech behaviors. Conclusions: Motor control for babble appears to be influenced by the balanced interaction between developing motor and linguistic systems, such that variation in linguistic complexity systematically evinces changes in motor organization apparently to meet these demands. This same effect was noted among chewing and jaw oscillation; task-dependent changes in mandibular control were noted across behaviors. KEY WORDS: speech, development, motor control, mandible, human, A theoretical framework of typical or disordered speech entails a robust representation of speech development; a crucial element in this representation is incorporating or segregating the influences of extant mechanisms [...]

Purpose: The ontogeny of mandibular control is important for understanding the general neurophysiologic development for speech and alimentary behaviors. Prior investigations suggest that mandibular control is organized distinctively across speech [...]

This investigation was designed to describe the development of lip and jaw coordination during speech and to evaluate the potential influence of speech motor development on phonologic development. Productions of syllables containing bilabial consonants were observed from speakers in four age groups (i.e., 1-year-olds, 2-year-olds, 6-year-olds, and young adults). A video-based movement tracking system was used to transduce movement of the upper lip, lower lip, and jaw. The coordinative organization of these articulatory gestures was shown to change dramatically during the first several years of life and to continue to undergo refinement past age 6. The present results are consistent with three primary phases in the development of lip and jaw coordination for speech: integration, differentiation, and refinement. Each of these developmental processes entails the existence of distinct coordinative constraints on early articulatory movement. It is suggested that these constraints will have predictable consequences for the sequence of phonologic development. KEY WORDS: speech development, motor control, articulatory movement, lips, jaw