title: Development and phonetic differentiation of speech movement patterns.
abstract: It is often hypothesized that speech production units are less distinctive in young children and that generalized movement primitives, or templates, serve as a base on which distinctive, mature templates are later elaborated. This hypothesis was examined by analyzing the shape and stability of single close-open speech movements of the lower lip recorded in 4-year-old, 7-year-old, and adult speakers during production of utterances that varied in only a single phoneme. To assess the presence of a generalized template, lower lip movement sequences were time and amplitude normalized, and a pattern recognition procedure was implemented. The findings indicate that speech movements of children already converged on phonetically distinctive patterns by 4 years of age. In contrast, an index of spatiotemporal stability demonstrated that the stability of underlying patterning of the movement sequence improves with maturation.
authors.affiliation: Purdue University, West Lafayette, Indiana 47907, USA. goffman@purdue.edu
authors.forename: L
authors.initials: L
authors.lastname: Goffman
authors.forename: A
authors.initials: A
authors.lastname: Smith
mesh_terms: D000328:Adult; D000367:Age Factors; D000375:Aging / Q000502:physiology; D002648:Child; D002657:Child Development / Q000502:physiology; D002675:Child, Preschool; D005260:Female; D006801:Humans; D008297:Male; D010700:Phonetics; D013060:Speech / Q000502:physiology*; D013068:Speech Production Measurement / Q000379:methods*