Production constraints on utterance-final consonant characteristics in babbling

Relationship between the target word form and children's productions: place of articulation in Consonant-Vowel-Consonant (C1VC2) words in American English

The aim of the present study was to investigate relationships between characteristics of children's target words and their actual productions during the single-word period in American English. Word productions in spontaneous and functional speech from 18 children acquiring American English were analyzed. Consonant sequences in 3,328 consonant-vowel-consonant (C₁VC₂) target words were analyzed in terms of global place of articulation (labials, coronals, and dorsals). Children's actual productions of place sequences were compared between target words containing repeated place sequences (e.g., mom, map, dad, not) and target words containing variegated place sequences (e.g., mat, dog, cat, nap). Overall, when the target word contained two consonants at the same global place of articulation (e.g., labial-labial, map; coronal-coronal, not), approximately 50% of children's actual productions matched consonant place characteristics. Conversely, when the target word consisted of variegated place sequences (e.g., mat, dog, cat, nap), only about 20% of the productions matched the target consonant sequences. These results suggest that children's actual productions are influenced by their own production abilities as well as by the phonetic forms of target words.

Vowel Context Effects on Consonant Repetition in Early Words

Purpose Consonant repetitions within words are a well-attested speech error pattern in children's early speech acquisition. We investigated the role of intervening vowel context in understanding speech forms containing consonant repetitions in early words. Intrasyllabic consonant-vowel (CV) sequences within consonant-vowel-consonant (CVC) and consonant-vowel-consonant-vowel (CVCV) forms containing consonant repetitions were analyzed to evaluate whether children's lack of independent movement control for the tongue in word-level sequences might contribute to these observed speech patterns. Method Spontaneous speech data produced by 10 typically developing children learning American English were analyzed longitudinally from the onset of word use to 36 months. Overall patterns and word shape effects for nine CV combinations occurring in their CVC and CVCV word shapes that contained repeated nonadjacent consonants and the intervening vowel were analyzed. Results Three CV combinations-coronal-front vowel, labial-central vowel, and dorsal-back vowel-occurred at above-chance levels. Preference for these CV patterns was strong in CVCV but not in CVC word shapes. These CV combinations occurred frequently at all time periods analyzed for CVCV's while decreasing across time for CVC's. Conclusions Analysis of intrasyllabic patterns within word forms containing consonant repetitions revealed that consonant repetitions in many early words occurred at above-chance levels in the context of articulatorily compatible vowels. Results suggest that children's production system capacities are an important contributing principle accounting for vowel context effects within word forms containing consonant repetitions during earliest speech acquisition.

Acquisition of serial complexity in speech production: a comparison of phonetic and phonological approaches to first word production

Comparison was made between performance-based and competence-based approaches to the understanding of first word production. The performance-related frame/content approach is representative of the biological/functional perspective of phonetics in seeking explanations based on motor, perceptual and cognitive aspects of speech actions. From this perspective, intrasyllabic consonant-vowel (CV) co-occurrence patterns and intersyllabic sequence patterns are viewed as reflective of biomechanical constraints emerging from mandibular oscillation cycles. A labial-coronal sequence effect involved, in addition, the problem of interfacing the lexicon with the motor system, as well as the additional problem of initiation of movement complexes. Competence-based approaches to acquisition are within the generative phonological tradition; involving an initial assumption of innate, speech-specific mental structures. While various current phonological approaches to acquisition involve consideration of sequence effects and intrasyllabic patterns, they do not adequately establish the proposed mental entities in infants of this age, and are nonexplanatory in the sense of not considering the causes of the structures and constraints that they posit.

Vocal development of 9-month-old babies with cleft palate

This study compared the prelinguistic vocal development of 9-month-old babies with unrepaired cleft palate (n = 30) and age-matched peers (n = 15). Samples of the babies' spontaneous vocalizations were obtained while they interacted with their primary caregiver during play. The groups were compared on a number of variables including (a) canonical babbling ratios, (b) percentage of babies who reached the canonical babbling stage by 9 months, (c) syllable and segmental aspects of babbling, and (d) vocal frequency. Results indicated that the babies with cleft palate had smaller canonical babbling ratios than their age-matched peers, with just 57% of the babies with cleft palate reaching the canonical babbling stage by 9 months compared to 93% of the noncleft babies. Although syllable types and length were similar for the two groups, differences were noted for consonant characteristics. The babies with cleft palate had smaller consonant inventories, with fewer stops, glides, and velars noted. Glottals occurred more frequently in the vocalizations of the babies with cleft palate. Finally, no statistically significant difference was noted in the number of vocalizations produced by the two groups. Some possible explanations for why babies with cleft palate are delayed in babbling are explored.

Deriving speech from nonspeech: a view from ontogeny

A comparison of babbling and early speech, word patterns of languages, and, in one instance, a protolanguage corpus, reveals three basic movement patterns: (1) a 'Frame' provided by the cycles of mandibular oscillation underlying the basic mouth close-open alternation of speech; this Frame appears in relatively 'pure' form in the tendency for labial consonants to co-occur with central vowels; (2) two other intracyclical consonant-vowel (CV) co-occurrence patterns sharing the alternation: coronal consonants with front vowels and dorsal consonants with back vowels; (3) an intercyclical tendency towards a labial consonant-vowel-coronal consonant (LC) sequence preference for word initiation. The first two patterns were derived from oral movement capabilities which predated speech. The Frame (1) may have evolved from ingestive cyclicities (e.g. chewing). The intracyclical consonant-vowel (CV) co-occurrence patterns involving tongue position constraints common to consonants and vowels (2) may result from the basic biomechanical property of inertia. The third pattern (LC) was a self-organizational result of pressures for interfacing cognition with action - a result which must have numerous analogs in other domains of movement organization.

An embodiment perspective on the acquisition of speech perception

Understanding the potential relationships between perception and production is crucial to explanation of the nature of early speech acquisition. The 'embodiment' perspective suggests that mental activity in general cannot be understood outside of the context of body activities. Indeed, universal motor factors seem to be more responsible for the distribution of early production preferences regarding consonant place and manner, and use of the vowel space than the often considerable cross-language differences in input available to the perceptual system. However, there is evidence for a perceptual basis to the establishment of a language-appropriate balance of oral-to-nasal output by the beginning of babbling, illustrating the necessary contribution of 'extrinsic' perceptual information to acquisition. In terms of representations, at least one assumption that segmental units underlying either perception or production in early phases of acquisition may be inappropriate. Our work on production has shown that the dominant early organizational structure is a relatively unitary open-close 'frame' produced by mandibular oscillation. Consideration of the role of 'intrinsic' (self-produced) perceptual information suggests that this frame may be an important basis for perceptual as well as production organization.