Perception of aspiration and place of articulation of Cantonese initial stops by normal and sensorineural hearing-impaired listeners.

This study investigated the use of acoustic cues to the perception of aspiration and place of articulation of Cantonese initial stops by bilateral severely hearing-impaired (n = 14) and normal-hearing (n = 14) adolescents. The stimuli were consonant-vowel (CV) words spoken by two male speakers in which the initial consonants /ph, p, th, t, kh, k/ were followed by the diphthong /[symbol: see text]i/. Subjects listened to the stimuli through a loudspeaker and chose the correct initial consonant among six choices. Three test conditions (short, medium and long voice onset time, or VOT) were prepared by increasing the VOT of unaspirated stops and by decreasing the VOT of aspirated stops. The results showed that the presence of aspiration noise was an important cue for normal listeners in the perception of aspiration, but not for hearing-impaired listeners. Hearing-impaired listeners used formant transitions as the main cue to the perception of aspiration. VOT was a weak aspiration cue for both groups. In the perception of place of articulation, normal listeners appeared to rely mainly on formant transitions and release burst information rather than VOT. The recognition of place by hearing-impaired listeners was at chance level for all the experimental stimuli, showing that these listeners were unable to use VOT, formant transitions or release burst information as cues to place.