Patterns of the Word-final /z/-devoicing and Word-initial Voiceless Stop Aspiration in English

This study analyzed the correlation between word-final /z/-devoicing and the aspiration of following word-initial voiceless stops. The results showed that at word boundaries, /z/ commonly undergoes devoicing, which in turn limits the application of aspiration. When the place of articulation for the voiceless stop is alveolar, the rate of aspiration is significantly lower, attributed to the universal tendency for alveolar sounds to be involved in consonant weakening, such as VOT reduction. The stress factor in English was found to overlap with another environment for aspiration, the word-initial position. Aspiration was more frequently applied in roots, likely due to the more pronounced prosodic weight in root positions. When voiceless stops serve as a complex onset, the distance from following stressed vowel and the tendency for a following sonorant consonant to devoice in English increased the application of aspiration. While gender did not affect aspiration, there was a correlation between age and aspiration, as reduced lung function with aging contributes to this relationship.