The relation of articulatory and vocal auditory–motor control in typical speakers

Purpose: The purpose of this study was to explore the relationship between feedback and feedforward control of articulation and voice by measuring reflexive and adaptive responses to first formant (F₁) and fundamental frequency (f_o) perturbations. In addition, perception of F₁ and f_o perturbation was estimated using passive (listening) and active (speaking) just noticeable difference paradigms to assess the relation of auditory acuity to reflexive and adaptive responses. Method: Twenty healthy women produced single words and sustained vowels while the F₁ or f_o of their auditory feedback was suddenly and unpredictably perturbed to assess reflexive responses or gradually and predictably perturbed to assess adaptive responses. Results: Typical speakers’ reflexive responses to sudden perturbation of F₁ were related to their adaptive responses to gradual perturbation of F₁. Specifically, speakers with larger reflexive responses to sudden perturbation of F₁ had larger adaptive responses to gradual perturbation of F₁. Furthermore, their reflexive responses to sudden perturbation of F₁ were associated with their passive auditory acuity to F₁ such that speakers with better auditory acuity to F₁ produced larger reflexive responses to sudden perturbations of F₁. Typical speakers’ adaptive responses to gradual perturbation of F₁ were not associated with their auditory acuity to F₁. Speakers’ reflexive and adaptive responses to perturbation of f_o were not related, nor were their responses related to either measure of auditory acuity to f_o. Conclusion: These findings indicate that there may be disparate feedback and feedforward control mechanisms for articulatory and vocal error correction based on auditory feedback.