Allocation of attention to real-time visual speech feedback in a digital mirror

Abstract

The role of sensory feedback in speech motor control is typically investigated by observing the behavioral and/or neurological response to experimental feedback perturbation. The function of feedback and its use in typical control is therefore inferred from responses under atypical conditions. The present study avoided perturbation, using eye tracking and a digital mirror (continuous video relay from a webcam) to examine how speakers attend to real-time visual feedback across normal speech and non-speech tasks. Fixation locations and durations were recorded during a period of rest prior to task onset (no-task condition), a recitation of the ABC’s, a re-telling of a popular children’s story (Goldilocks and the Three Bears), and parallel clear speech versions of the latter two tasks. Analysis of gaze showed that participants overall seemed to avoid fixating on their self-image, and that avoidance increased during speech tasks compared to non-speech “rest.” Across the two content areas (ABC’s vs. storytelling), participants’ self-gaze was concentrated more heavily on speech-relevant areas during storytelling, and no differences in gaze were observed between casual and clear speech. These data suggest an increased role for sensory feedback during complex linguistic tasks, as well as indicating an overall aversion towards realistic visual self-feedback.