An audiovisual test of kinematic primitives for visual speech perception.

Isolated kinematic properties of visible speech can provide information for lip reading. Kinematic facial information is isolated by darkening an actor's face and attaching dots to various articulators so that only moving dots can be seen with no facial features present. To test the salience of these images, the authors conducted experiments to determine whether the images could visually influence the perception of discrepant auditory syllables. Results showed that these images can influence auditory speech independently of the participant's knowledge of the stimuli. In other experiments, single frozen frames of visible syllables were presented with discrepant auditory syllables to test the salience of static facial features. Although the influence of the kinematic stimuli was perceptual, any influence of the static featural stimuli was likely based on participant's misunderstanding or postperceptual response bias.