An Integrated Approach to Concurrently Measure Corrective and Adaptive Responses to Auditory Errors

Area of Science:

• Neuroscience
• Speech Science
• Auditory Perception

Background:

• Speech production involves complex feedforward and feedback control systems.
• Auditory errors are crucial for refining speech accuracy.
• Current methods for studying these systems in isolation are time-consuming and impractical.

Purpose of the Study:

• To develop and validate a novel paradigm for concurrently examining feedforward and feedback speech control systems.
• To assess the brain's adaptive and corrective responses to auditory perturbations.

Main Methods:

• Applied varying auditory perturbation magnitudes (0-500 Hz) and directions (ε-to-ɪ, ε-to-ӕ) in a randomized, rapid-switching paradigm.
• Measured formant changes at early (0-100 ms) and late (200-300 ms) production time points.
• Calculated adaptive responses (feedforward) and corrective responses (feedback) based on measured formant changes.

Main Results:

• Participants exhibited adaptive and corrective responses opposing the perturbation direction.
• Responses were proportionally larger for smaller perturbations, particularly in the ε-to-ɪ direction.
• Individual sensitivity to ε-to-ɪ perturbations correlated with sensitivity to ε-to-ӕ perturbations.

Conclusions:

• The brain demonstrates sensitivity to auditory error magnitude and direction for both feedforward and feedback control.
• The proposed paradigm offers an efficient method for concurrently measuring feedforward and feedback contributions to speech control.
• Findings suggest comparable error sensitivity in the ε-to-ɪ and ε-to-ӕ speech sound contexts.