Conversing in the presence of a competing conversation : effects on speech production

How does a background conversation affect a foreground conversation? In this scenario, and unlike traditional studies of noise-induced speech modification (Lombard speech), listeners have to cope with the additional challenge of competing speech material. In the current study, pairs of talkers engaged in natural dialogs in the absence or presence of another talker pair. Changes in speech level revealed only a small energetic masking effect of the background pair, but very large modifications in prosodic parameters (F0, speech rate) were observed during overlaps within conversations. The presence of the background pair led to increases in the numbers of dysfluencies, mistiming and interruptions, suggesting that interlocutors suffer from competing speech in ways which are not well-described by Lombard speech modifications. Longer inter-turn pauses seen in the background present condition may indicate that listeners monitor the other conversation to avoid temporally-competing speech material where possible