UNIGE document Scientific Article
previous document  unige:142451  next document
add to browser collection
Title

Animated virtual characters to explore audio-visual speech in controlled and naturalistic environments

Authors
Albert, Louis
Provost, Antoine
Published in Scientific reports. 2020, vol. 10, no. 1, 15540
Abstract Natural speech is processed in the brain as a mixture of auditory and visual features. An example of the importance of visual speech is the McGurk effect and related perceptual illusions that result from mismatching auditory and visual syllables. Although the McGurk effect has widely been applied to the exploration of audio-visual speech processing, it relies on isolated syllables, which severely limits the conclusions that can be drawn from the paradigm. In addition, the extreme variability and the quality of the stimuli usually employed prevents comparability across studies. To overcome these limitations, we present an innovative methodology using 3D virtual characters with realistic lip movements synchronized on computer-synthesized speech. We used commercially accessible and affordable tools to facilitate reproducibility and comparability, and the set-up was validated on 24 participants performing a perception task. Within complete and meaningful French sentences, we paired a labiodental fricative viseme (i.e. /v/) with a bilabial occlusive phoneme (i.e. /b/). This audiovisual mismatch is known to induce the illusion of hearing /v/ in a proportion of trials. We tested the rate of the illusion while varying the magnitude of background noise and audiovisual lag. Overall, the effect was observed in 40% of trials. The proportion rose to about 50% with added background noise and up to 66% when controlling for phonetic features. Our results conclusively demonstrate that computer-generated speech stimuli are judicious, and that they can supplement natural speech with higher control over stimulus timing and content.
Identifiers
PMID: 32968127
Full text
Structures
Research groups Groupe Anne-Lise Giraud (939)
Human Neuron Lab (1034)
Project
Swiss National Science Foundation: 167836
Citation
(ISO format)
THÉZÉ, Raphaël et al. Animated virtual characters to explore audio-visual speech in controlled and naturalistic environments. In: Scientific Reports, 2020, vol. 10, n° 1, p. 15540. doi: 10.1038/s41598-020-72375-y https://archive-ouverte.unige.ch/unige:142451

207 hits

81 downloads

Update

Deposited on : 2020-10-02

Export document
Format :
Citation style :