Vocalization-induced enhancement of the auditory cortex responsiveness during voice F₀ feedback perturbation

Objective: The present study investigated whether self-vocalization enhances auditory neural responsiveness to voice pitch feedback perturbation and how this vocalization-induced neural modulation can be affected by the extent of the feedback deviation. Methods: Event-related potentials (ERPs) were recorded in 15 subjects in response to +100, +200 and +500 cents pitch-shifted voice auditory feedback during active vocalization and passive listening to the playback of the self-produced vocalizations. Results: The amplitude of the evoked P₁ (latency: 73.51 ms) and P₂ (latency: 199.55 ms) ERP components in response to feedback perturbation were significantly larger during vocalization than listening. The difference between P₂ peak amplitudes during vocalization vs. listening was shown to be significantly larger for +100 than +500 cents stimulus. Conclusions: Results indicate that the human auditory cortex is more responsive to voice F₀ feedback perturbations during vocalization than passive listening. Greater vocalization-induced enhancement of the auditory responsiveness to smaller feedback perturbations may imply that the audio-vocal system detects and corrects for errors in vocal production that closely match the expected vocal output. Significance: Findings of this study support previous suggestions regarding the enhanced auditory sensitivity to feedback alterations during self-vocalization, which may serve the purpose of feedback-based monitoring of one's voice.