ABSTRACT

How do infants learn to understand and produce spoken language? Despite decades of intensive investigation, the answer to this question remains largely a mystery. This is, in part, because although the use of language seems straightforward to adult native speakers, speech recognition and production present the infant with numerous difficult computational problems (see Lively, Pisoni, & Goldinger, 1994). First of all, processing speech is difficult both because it is extended in time and because it is subject to considerable variability across speakers and contexts. Moreover, even with an accurate representation of the underlying phonetic content of a heard utterance, mapping this representation onto its meaning is difficult because the relation of spoken words to their meanings is essentially arbitrary. On the output side, the infant must learn to produce comprehensible speech in the absence of any direct feedback from caretakers or the environment as to what articulatory movements are required to produce particular sound patterns. Finally, the processes of learning to understand speech and learning to produce it must be closely related (although certainly not synchronized; Benedict, 1979) to ensure that they eventually settle on mutually consistent solutions.