BABBLING AND FIRST WORDS - PHONETIC SIMILARITIES AND DIFFERENCES

There is a strong consensus that the sounds and sound patterns of babb ling and early speech are basically the same. The common state is one of ''Frame Dominance'' - a syllabic frame produced by an open-close ma ndibular oscillation dominates both stages, with limited ability of ot her articulators, including the tongue to produce active intrasyllabic and intersyllabic changes. The question of whether the first words ar e similar to babbling in all respects was evaluated in 4 subjects, usi ng a database consisting of 152 hours of audio recording. A tendency t owards increasing use of labial consonants relative to alveolar conson ants was observed in 3 of the four subjects, and this was interpreted as a regression towards an easier production form. Progress in words t ook the form of an increase in variegation of utterances, mainly due t o vowel variegation, much of which derived from an increase in the use of high vowels and mid back yowels, especially in wordfinal position. The presence of regression and the limited nature of the progress wer e taken as evidence of the strength of the Frame Dominance pattern and the consequent difficulty of escaping from it. (C) 1997 Elsevier Scie nce B.V.