Acoustic cues for the perception of aspiration in Cantonese initial stops Poon Man Wai, May A dissertation submitted in partial fulfilment of the requirements for the Bachelor of Science

This study investigated the significant acoustic cues used in the perception of aspiration contrast in Cantonese initial stops by normal hearing adults. The effects of vowel characteristics, aspiration noise level and voice-onset time (VOT) duration on aspiration perception in Cantonese initial stops were studied. The stimuli were consonant-vowel (CV) real words recorded by a male Cantonese native speaker. Initial stops /p, p, t, t, k, kV combined with the same vowel / a / to give the stimuli. A total of twenty-four stimuli conditions were edited from the natural stimuli by varying the vowel ('Aspirated vowel' or TJnaspirated vowel'), aspiration noise level ('-/Aspiration noise' or X Aspiration noise') and VOT duration ('Long VOT' or 'Short VOT') independendy. Ten subjects listened to the stimuli and selected one from the six real words (@ / p a / 'father', §\ /pa1/ 'on all fours', JX A a / 'dozen', fffi / t 1 ^ / 'he', ^ / k a / 'home', -fc / k h a / 'compartment') which he or she might find the same or the most similar to the presented stimulus. The results showed that the vowel characteristics of the stimuli were the main cues used on aspiration perception by the normal hearing adults. The cueing effect of 'Aspirated vowel' was independent from the other two acoustic parameters. Although both aspiration noise level and VOT duration showed significant cueing effects on aspiration perception in Cantonese initial stops, only the co-existing of ' / aspiration noise' and 'Long VOT' was sufficient to cue for the aspirated perceptual response in the absence of 'Aspirated vowel'.