Word duration in early child speech

Word duration in early child speech was examined through a longitudinal study of a set of frequently occurring words for three subjects. These samples were controlled for phonetic form. Durations were measured from wide- and narrow-band spectrograms. Results show that for some words, but not the majority, duration decreased over time; this effect does not appear to be due to increased familiarity with individual lexical items. Generally, word duration variations within the tested time ranges can be attributed to the effect of position-in-utterance. From the time a child first combines two words into a single phrase, a nonfinal word will be produced with a shorter duration than it would have in isolated or final position in an utterance.