The Role of Amplitude Envelope in Cantonese Lexical Tone Perception: Implications for Cochlear Implants

Amplitude envelope co-varies with F0 in Mandarin lexical tones. It can cue lexical tone perception in a tone language such as Mandarin which uses different pitch contours for phonemic contrasts. The current study investigated whether amplitude envelope could also aid the perception of lexical tones in a language such as Cantonese which uses both pitch contour and relative pitch height for phonemic contrasts. Stimuli containing only the amplitude envelope of Cantonese lexical tones were used, and native speakers of Cantonese identified the lexical tones contained in the stimuli with above-chance accuracy. Thus, amplitude envelope could cue pitch contour and pitch height for lexical tone perception. Amplitude envelope was found to co-vary with F0 in Cantonese lexical tones, and the degree of their covariability was a fair predictor of Cantonese lexical tone perception using amplitude envelope alone. Clinical implications of these findings for cochlear implants were discussed.