THE ARTICULATORY BASIS OF BABBLING

This article evaluates the ''Frames, then Content'' hypothesis for spe ech acquisition, which states that much of the patterning of babbling is a direct result of production of syllabic ''Frames'' by means of rh ythmic mandibular oscillation, with relatively little of the intrasyll abic and intersyllabic ''Content'' of the syllable-like cycles under m andible-independent control. Analysis was based on a phonetically tran scribed corpus of 6,659 utterances of 6 normally developing infants ob tained from one-hour weekly audio-recordings over a 4-6 month period. Intrasyllabic predictions were that front vowels would preferentially co-occur with front (alveolar) consonants, back vowels with back (vela r) consonants, and central vowels with labial consonants, with the lat ter effect presumably resulting from mandibular oscillation alone. Int ersyllabic predictions were for more variegation in tongue height for vowels than in front-back tongue movement, and for consonant manner ch anges to predominate over place changes (related primarily to mandibul ar oscillation). All 30 individual predictions from both hypotheses we re confirmed, leading to a conception of the articulatory basis of bab bling as ''Frame Dominance.''