The Role of Lombard Speech and Gaze Behavior in Multi-Talker Conversations

Effective communication with multiple conversational partners in cocktail party conditions can be attributed to successful auditory scene analysis. Talkers unconsciously adjust to adverse settings by introducing both verbal and non-verbal strategies, such as the Lombard effect. The Lombard effect has traditionally been defined as an increase in vocal intensity as a response to noise, with the purpose of increasing self-monitoring for the talker and intelligibility for conversational partners. To assess how the Lombard effect is utilized in multimodal communication, speech and gaze data were collected from four multi-talker groups with pre-established relationships. Each group had casual conversations in both quiet settings and scenarios with external babble noise. Results show that fifteen out of sixteen talkers exhibited an average increase in loudness during interruptive speech in all conditions withand without external babble noise when compared to unchallenged sections of speech. Comparing gaze behavior during periods of a talkers own speech to periods of silence showed that the majority of talkers had more active gaze when speaking.