Our work on serial organization of speech concerns the way speech makes use of articulatory space in the time domain. According to our Frame/Content theory, the most fundamental time-based use of this space is a Frame cycle arising from an alternation between closed (consonantal) and open (vocalic) mandibular phases. We have also described three characteristic intoracyclical consonant-vowel (CV) co-ccurrence patterns involving t he front-back dimension of vowels in infants, languages and in one protolanguage corpus: I. 'Pure Frames"-labia consonants with central vowels; 2. "Fronted Frames"-coronal consonants with front vowels, and 3. "Backed Frames"-dorsal consonants with back vowels. We have also found one prevalent intercyclical (consonant vowel-consonant) pattern-a tendency to initiate a word with a labial consonant, and, after the vowel, continue with a coronal consonant (LC). These patterns are considered to form part of a "Motor Core" for serial speech production. Aims: 1. Core Properties. a. Intracyclical: Vowel height. We will investigate the hypothesis that it infants, tongue inertial effects will be again be evident in co-occurrences between lingual (coronal and dorsal consonants and nearby high vowels, and in a favoring of low vowels in labial environments. In contrast, in languages, perceptual distinctiveness demands may result in disfavoring high vowels following some lingua consonants. b. Intercyclical: Dorsal Consonants. We will investigate the hypothesis that dorsals are more likely to follow labials in CVC sequences than coronals, in both infants and languages. Consequently, the core intercyclical consonantal pattern may be labial-lingual rather than simply labial-coronal, perhaps due to ease o labial initiation .2. Matching of Speech Input. We will investigate the perceptual role of ambient language patterns on speech acquisition in a comprehensive quantitative cross-language study of infant development o correct match of output to ambient language input. Seven indices of speech development will be evaluated in infants in 12 language environments. 3. Speech organization in infants with Multichannel Cochlear Implantation: We will explore the implications for theory, assessment and intervention of the prediction that at increasingly important subpopulation-very young infants with severe-to-profound hearing loss receiving Multichannel Cochlear Implantation-will produce the three CV co-occurrence patterns involving the front-back dimension of vowels.