Speech Production Stability: contributions and interactions of somatosensory and auditory feedback in on-line compensation – SpeechStab

Speech production stability is crucial for efficient speech communication in basic daily situations. While auditory and somatosensory feedback contribute to speech motor control, it is still unknown how these sensory inputs interact to ensure the required stability. Our hypotheses are 1) that somatosensory feedback plays a predominant role in quick on-line compensation due to shorter response latency than auditory feedback, and 2) that the somatosensory-based stability mechanism is acquired during speech development to achieve speech-relevant auditory goals. We examine those hypotheses by measuring tongue posture stabilization in sensory-intact and sensory-impaired individuals in behavioral tests using tongue perturbations and by comparing the performance across subject groups. Simulations with a biomechanical tongue model are used to help interpret the observations. Our project will provide clues as to the mechanisms that enable speech production stability using sensory feedback.