Pitch and duration as a basis for entrainment of overlapped speech onsets

The present paper reports on the impact of pitch accents and duration on temporal organisation of overlapping speech onsets in spontaneous dialogue. We observe a non-random pattern of overlap initiations within intervals between consecutive pitch accents, thus extending our earlier reports of a similar effect within vowel-to-vowel intervals. The latter finding was interpreted as a tendency to start overlapped speech directly before perceptually prominent vocalic onsets. In an attempt to reconcile these results, we investigate whether the effect observed on vowel-to-vowel intervals is influenced by presence of pitch accents and lengthening, both of which are known to be correlated with perceptual prominence. We find a strong effect of duration, which, however, does not on its own account fully for the observed pattern, indicating that other correlates of prominence might be involved in guiding the timing of overlap onsets.