Voicing and aerodynamics of /h/ produced by women, men, and children

Patterns of consonantal voicing, especially as measured by voice onset time (VOT), have played an important role in discussions of speech timing control across populations. For example, relatively late acquisition of adultlike VOT values for voiceless aspirated stops in normal children has been attributed to the precise laryngeal-oral phasing required for these sounds. Implicit in such arguments is the assumption that the laryngeal and oral events themselves are comparable across subject groups. The present study attempts to assess the validity of this assumption in normal English-speaking women, men, and 5-year-old children. Recordings of oral airflow, intraoral air pressure, and acoustics were made as subjects produced a variety of voiceless consonants in prestress position within a carrier phrase. Analysis here focuses on /h/, which involves no oral obstruction and therefore affords the clearest picture of events at the glottis during the consonant. In these data, the patterns of flow increase, voicing offset and voicing onset during abduction for /h/ show certain differences across groups and suggest that some aspects of laryngeal behavior are not identical across these populations. Results are discussed in terms of group-related differences in anatomy and aerodynamic quantities.