ABSTRACT
The progress that has been made in infant vocal development research over the past two and a half decades began with the simple decision to abandon description based on operational-level units of mature speech systems and to replace that style of description with a more ethologically straightforward method. In particular the description of infant sounds began to be formulated without alphabetical speech sounds as prime units. Instead, baby sounds were described in terms that attempted to hear the infants’ own voices. When we sought to attend to babies on their own terms and to relate to their vocal sounds as parents might, no longer shoe-horning their utterances into preconceived adult segmental speech categories, we found stages of development that had eluded prior generations of scholars (chaps. 1-4).
