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The acoustic characteristics of crying behavior displayed in 2 groups of newborn infants are reported. The crying episodes of 10 full-term and 10 preterm infants were audio recorded and analyzed with regard to the long-time average spectrum (LTAS) characteristics. An LTAS display was created for each infant's non-partitioned crying episode, as well as for 3 equidurational partitions of the crying episode. Measures of first spectral peak, mean spectral energy, and spectral tilt were revealing of differences between full-term and preterm infants' non-partitioned crying episodes. In addition, the full-term infants demonstrated significant changes in their crying behavior across partitions, whereas the preterm infants changed little across the crying episode. Discussion focuses on possible differences between full-term and preterm infants in their neurophysiological maturity, and the subsequent impact on their speech development. The importance of examining entire crying episodes when evaluating the crying behavior of infants is also discussed.

The duration and vocal fundamental frequency (F o ) of inspiratory cries produced by a group of 20 healthy infants were measured. Similar acoustic measures were applied to the cries immediately preceding and following an inspiratory cry as a means of characterizing an inspiratory “event.” Results were that the number of inspiratory cries varied considerably from child to child during a complete crying episode. The duration and F o of inspiratory cries were significantly shorter and higher, respectively, in comparison to cries immediately preceding and following the inspiratory cry. In addition, the gap duration following an inspiratory cry was significantly greater than the pre-inspiratory gap duration. Discussion centers on the anatomical and physiological bases of inspiratory cry phonation. Implications as well as the need to consider the inspiratory portion of crying behavior when examining infants at risk for respiratory distress also are discussed.

The results of a longitudinal study of seven children's consonant production are reported. Data were collected at monthly intervals between the ages of 8 and 25 months. All glossable and non-glossable utterances that occurred during data collection were combined to determine: (1) the number and types of consonants occurring in the children's syllable-initial and syllable-final inventories, and (2) the relative frequency of occurrence of the major manner and place sound classes. The results were comparable to those of previous investigations, although slightly larger and more diverse consonant types were noted in the children's earliest monthly inventories. The advantages of considering non-glossed vocalizations when assessing a young child's phonetic abilities are discussed.

Acoustic characteristics of American English sentence stress produced by native Mandarin speakers are reported. Fundamental frequency (F0), vowel duration, and vowel intensity in the sentence-level stress produced by 40 Mandarin speakers were compared to those of 40 American English speakers. Results obtained from two methods of stress calculation indicated that Mandarin speakers of American English are able to differentiate stressed and unstressed words according to features of F0, duration, and intensity. Although the group of Mandarin speakers were able to signal stress in their sentence productions, the acoustic characteristics of stress were not identical to the American speakers. Mandarin speakers were found to produce stressed words with a significantly higher F0 and shorter duration compared to the American speakers. The groups also differed in production of unstressed words with Mandarin speakers using a higher F0 and greater intensity compared to American speakers. Although the acoustic differences observed may reflect an interference of L1 Mandarin in the production of L2 American English, the outcome of this study suggests no critical divergence between these speakers in the way they implement American English sentence stress.