July 18, 2022

PhD Thesis Defence - Keith Leung

Keith Leung will be defending his PhD thesis:

Perception-production relationship of lexical tones

Friday, July 29th, 9am via Zoom.

Please use this websurvey link to request the Zoom log in credentials by July 22nd.


The link between perception and production is predicted to be close, but empirical findings on this relationship are mixed. While a perception-production relationship has been found for various speech sounds, some research has failed to support such a link. To explain this apparent contradiction, a proposed view is that a perception-production relationship should be established through the use of critical perceptual cues. This dissertation project aims to examine this view by using Mandarin tones as a test case, since the perceptual cues for Mandarin tones consist of a perceptually critical pitch direction cue and a non-critical pitch height cue. As there was little research on the perception-production relationship of lexical tones based on acoustic cues, the first study explored the correlation between perception and production of Mandarin Tone 2 for each of five acoustic cues which included critical pitch direction-related cues, non-critical height-related cues and a temporal cue. A perception-production correlation was only found for the critical perceptual cues. The second study investigated the proposal systematically by examining the defining features of critical and non-critical perceptual cues and the perception-production relationship of each cue for each Mandarin tone. The perceptual stimuli in the perception experiment were created by varying one critical and one non-critical perceptual cue orthogonally. The cues for tones produced by the same group of native Mandarin participants were measured. This study found that the critical status of perceptual cues primarily influenced the within- category and between-category perception for all tones. Using cross-domain bi-directional statistical modelling, a perception-production link was found for the critical perceptual cue only. A stronger link was obtained when within-category and between-category perception data were included in the modelling, as compared to using between-category perception data alone, suggesting a phonetically and phonologically driven perception-production relationship. Finally, the third study examined if forming a perception-production relationship could be clearly attributed to the use of critical perceptual cues. Using the same critical and non-critical cues as in the second study, the learning effects on the perception and production of each cue were measured for Mandarin learners whose native language was Indonesian, a non-tonal language, in a four- to six-week interval. A simultaneous improvement in perception and production was found for the critical perceptual cue only, supporting the notion that the critical perception cue was a contributing factor driving the link between perception and production.

Keywords: speech perception, speech production, perception-production relationships, Mandarin tones

Members of Examining Committee:

Chair: Nancy Hedberg
Supervisor: Yue Wang
Committee Member: Murray Munro
Committee Member: Henny Yeung
Examiner: Christian Guilbault (SFU French)
External Examiner: Chao-Yang Lee (Ohio University)

LING community members – including family and friends of the candidate – are welcome to attend this defence. 

Videoconference connection information will be provided only to those who RSVP to the event by July 22nd, (1 week prior to the defence date).  If you wish to attend this defence, RSVP via the websurvey link above.

Upcoming Thesis Defences