Task-Dependent Modulation of Auditory Feedback Control of Vocal Intensity

Area of Science:

• Speech production and perception
• Auditory feedback mechanisms
• Vocal control

Background:

• Auditory feedback is crucial for regulating voice fundamental frequency (f_o).
• f_o control is task-dependent, with sentence production eliciting larger responses to pitch perturbations than sustained vowels.
• This suggests auditory targets are scaled based on task precision requirements.

Purpose of the Study:

• To investigate if auditory feedback control of vocal intensity (loudness) is also modulated by speaking task.
• To compare vocal intensity responses to loudness perturbations during sentence versus sustained-vowel production.

Main Methods:

• Twenty-five English speakers produced sentences and sustained vowels.
• Participants heard their voice loudness perturbed (+/- 3 or 6 dB SPL for 200 ms).
• Vocal intensity responses and peak latencies were measured.

Main Results:

• Vocal intensity response magnitudes were significantly larger in sentence production (mean: 1.96 dB) than in vowel production (mean: 0.89 dB).
• Response magnitudes varied with perturbation size differently for upward and downward perturbations in sentence production.
• Peak response latencies were shorter in sentence production (mean: 184.94 ms) compared to vowel production (mean: 214.92 ms).

Conclusions:

• Auditory feedback control of vocal intensity is modulated by speaking task, similar to pitch control.
• Auditory targets for loudness are scaled according to the precision demands of the specific speaking task.