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P F MacNeilage

Publications and source records attributed to P F MacNeilage.

34 records · Page 2Linked to original sources
PubMed1975

Pursuit auditory tracking of dichotically presented tonal amplitudes.

In pursuit auditory tracking tasks subjects match a continuously varying pure tone presented to one ear with a second tone presented to the other ear and controlled by unidimensional movements of part of their motor system. In previous studies in which tonal frequency was varied, performance was significantly better when the tone controlled by a speech articulator (tongue, jaw) was presented to the right ear, rather than the left, but not if the tone was hand controlled. In this study tonal amplitude was varied in mandibular and manual tracking by 30 normal right-handed subjects. Small right-ear advantage was found for both tracking modes although it did not reach statistical significance. Frequency modulated stimuli may more effectively differentiate speech from nonspeech tracking because we may, as a result of speech experience, possess a more developed lateralized auditory-sensorimotor algorithm for frequency-motor relationships involving the mandible than for amplitude-motor relationships. Testable consequences of this hypothesis are outlined.

Acoustic Stimulation↗
PubMedDate not supplied

The motor core of speech: a comparison of serial organization patterns in infants and languages.

Comparison of serial organization of infant babbling and early speech with that of 10 languages reveals four movement-related design features reflecting a deep evolutionary heritage: (1) the cyclical consonant-vowel alternation underlying the syllable, a "Frame" for speech consisting of mandibular oscillation, possibly evolving from ingestive cyclicities (e.g., chewing) via visuofacial communicative cyclicities (e.g., lipsmacks); (2) three intracyclical consonant-vowel co-occurrence preferences reflecting basic biomechanical constraints-coronal consonants-front vowels, dorsal consonants-back vowels, and labial consonants-central vowels; (3) a developmental progression from above-chance to below-chance levels of intercyclical consonant repetition; (4) an ease-related labial consonant-vowel-coronal consonant sequence preference for word initiation. These design features presumably result from self-organizational responses to selection pressures, primarily determined by motor factors. No explanation for these design features is available from Universal Grammar, and, except for feature 3, perceptual-motor learning seems to have only a limited causal role in acquisition of any design feature.

Child↗
PubMedDate not supplied

Prosodic correlates of stress in babbling: an acoustical study.

Prelinguistic babbling often seems remarkably speech-like, not because it has recognizable words but because it seems to have adult-like prosody. To quantify this impression, we compared disyllabic sequences from five infants and five adults in terms of the use of frequency, intensity, and duration to mark stress. Significantly larger values for the three acoustic variables were observed on stressed than on unstressed syllables independent of syllable position for both groups. Adults showed the correlates of utterance final syllables--lower f0, lower intensity, and longer duration; infants showed only decrease in intensity. Ratios for stressed to unstressed syllables and participation of the three variables in stress production in individual disyllables were highly similar in both groups. No bias toward the English lexical trochaic stress pattern was observed. We conclude that infants in English environments produce adult-like stress patterns before they produce lexical items, which specify stress. Acoustic and perceptual analyses are used to explore stress marking by prelinguistic infants in an English language environment. Results show that infants employ the three acoustic correlates of stress in individual syllables in a manner largely similar to that of adult speakers, although they do not show second-syllable declination effects or an English language trochaic stress bias.

Adult↗
PubMedDate not supplied

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.

Humans↗
PubMedDate not supplied

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.

Biomechanical Phenomena↗
PubMedDate not supplied

Speech production.

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Cerebral Cortex↗
PubMedDate not supplied

Organization of babbling: a case study.

Speech is probably the most complex serially ordered behavior in living forms. However, no systematic investigation of the organization of speech-related output when it is presumably simplest, namely during the babbling stage, has been attempted. Transcriptions of 423 babbled utterances (1145 syllables) were obtained from one subject 7-12 months of age. Most results could be interpreted in terms of a basic mouth opening-closing alternation, responsible not only for the typical vowel-consonant alternation of babbling, but also for many prominent details including within-utterance variation in vowel height (often stress-related) and in degree of closure for consonants. The results suggest that a "frame" for babbling is provided by mandibular oscillation, perhaps reflected, when operating alone, in the common alternation between labial consonants and central vowels. Variation in the amplitude of this oscillation may be responsible for the within-utterance vowel height and consonant manner variation and much of the perceived stress variation. Further variation is attributed to fronting movements of the tongue, the effects of which often spread beyond single vowels and consonants.

Humans↗