The influence of utterance position on children's production of lexical stress.

Previous studies reporting acoustical data on children's production of lexical stress examined words produced in isolation (i.e., with no carrier phrase) or in utterance-final position. In such contexts, the final syllable of the words being examined was also the utterance-final syllable. Syllables produced in utterance-final position are known to be longer in duration and lower in intensity and F(0) compared to other syllables within utterances. Therefore, utterance-final effects may have obscured previous results on children's production of stress. Twenty children at approximately 6 years of age produced novel trochaic and iambic words in utterance-final and utterance-non-final position. Comparing productions across the two utterance positions suggested that reliance upon the utterance-final context was a confounding factor in past studies. Utterance-final position facilitated the iambic pattern of duration (short-long) and the trochaic pattern of intensity and F(0) (high-low). Utterance position sometimes affected trochees differently than iambs, especially in the duration of word-final syllables. The results are discussed in terms of past explanations of utterance position effects on acoustic characteristics of syllables.