Do children laugh like their parents? Conversational laughter mimicry occurrence and acoustic alignment in middle-childhood

Abstract

Laughter is ubiquitous and crucial in social interactions. In addition to conveying meaning, it is a valuable means for monitoring interlocutor mental states and mutual cognitive alignment. Laughter has been shown to be informative about the pragmatic development of pre-school children. The current paper investigates laughter mimicry and acoustic alignment in middle childhood in a corpus of parent-child and parent-adult computer-mediated conversations. We performed both distributional and acoustic analyses. While there was no significant differences in terms of laughter frequency between children and adults, laughter mimicry was significantly less frequent in parent-child than in parent-adult interactions, although balanced at an intra-dyad level. A spectro-temporal modulation analysis revealed that mimicking laughter exhibited an increase in low-frequency spectral modulations compared to non-mimicking laughter for all participants, partly explained by heightened arousal. To test whether this pattern was related to a local alignment to the partner’s preceding laughter, we compared distances from genuine and pseudo-random initiating-mimicry laughter pairs. In parent-adult interactions, confirming previous studies, laughs constituting genuine pairs were acoustically more similar than those constituting pseudo-random pairs. No such pattern was found in parent-child interactions. Our results suggest that although laughter production during middle-childhood resembles adult-like use in terms of frequency, arousal, and balance between interactants, it is still significantly different when considering laughter mimicry, both in terms of transitional probabilities and acoustic alignment between interlocutors. Our study forms a basis for discussion on current theoretical models of alignment, its interplay with interactional dynamics, and the entanglement of laughter use with pragmatic development.