OVERVIEW A    system of the ambient language involves a dynamic interplay of the child’s developing auditory, cognitive, articulatory, and sensorimotor mapping capabilities and vocal experiences over a period when vocal tract anatomy is changing in size and confi guration (Ménard, Schwartz, & Boë, 2004; Vorperian & Kent, 2007). Innate mechanisms have been proposed to explain how infants can accommodate changes in muscular and nonmuscular anatomy of the vocal tract to master vowel production during this period of anatomical, physiological, and perceptual development (Howard & Heselwood, 2002). Callan, Kent, Guenther, and Vorperian (2000) described an auditory feedback-based neural network model of speech production that was robust to developmental changes in the size and shape of the articulatory system for 11 English vowel targets. eir work illustrates the potential of modeling approaches to refi ne our hypotheses about these innate mechanisms and suggests that auditory feedback plays a critical role.