Synchronized cycles in ventilation and vocal activity during spontaneous conversational speech

Area of Science:

• Physiology
• Speech Science
• Human Behavior

Background:

• Spontaneous conversational speech involves complex coordination between respiratory and vocal systems.
• Understanding the interplay between ventilation and vocalization is crucial for fields like speech pathology and neuroscience.

Purpose of the Study:

• To investigate the correlation between oscillatory patterns in human ventilation and vocal activity during spontaneous conversation.
• To determine the extent of mutual entrainment between breathing and speaking rhythms in dyads.

Main Methods:

• Monitored ventilation and vocal activity in 10 human subjects conversing in five pairs (dyads).
• Analyzed oscillatory patterns within a range of cycle times (16–512 s).
• Quantified the degree of coupling and mutual entrainment between ventilation and vocal activity.

Main Results:

• One subject exhibited striking mutual entrainment between low-frequency oscillations in ventilation and vocal activity.
• Five subjects showed weaker coordination, while four displayed little to no coupling.
• Significant individual variability exists in the degree of ventilation-vocalization coupling during speech.

Conclusions:

• Mutual entrainment between ventilation and vocal activity rhythms is possible during spontaneous conversation.
• Individual differences in entrainment may be influenced by the strength of spontaneous ventilatory patterns.
• The degree of entrainment might also depend on the match between a speaker's ventilatory pattern and their partner's.