The dance of smiles: Comparing smile synchrony in nondistressed and therapy-seeking couples.

Dyadic affective processes are key determinants of romantic relationship quality. One such process termed emotional synchrony (i.e., the coupling of partners' emotions) has attracted growing attention in recent years. The present study focused on synchrony in partners' smiles, a nonverbal signal with significant social functions. Specifically, smile synchrony in the interactions of nondistressed couples was compared to smile synchrony in therapy-seeking couples. The former were predicted to show higher levels of smile synchrony. Data from the interactions of 61 (30 nondistressed and 31 treatment-seeking) couples were collected during a laboratory session while they engaged in four 6-min interactions during which they discussed positive or negative aspects of their relationship. FaceReader software was used to continuously code each partner's smile. Compared to treatment-seeking couples, nondistressed couples exhibited higher levels of smile synchrony, and such synchrony occurred in shorter time intervals. These results suggest that smile synchrony may be used as a behavioral signature of relationship quality. (PsycInfo Database Record (c) 2025 APA, all rights reserved).