Reading the Social Clock: Analyzing Nonverbal Coordination Dynamics in Casual Chat and Conflict.

While temporal coordination of nonverbal behaviors is considered crucial for successful communication, the underlying behavioral phenomena are poorly understood, and it remains unclear how coordination dynamics adapt to different social task demands. This study explores changes in interpersonal synchrony as dyads transition from a casual getting-acquainted conversation to a hierarchical conflict resolution task. Using full-body motion capture, we compared temporal alignment patterns in movement activity, head orientation, and body posture of 66 dyads interacting in both conditions. Results show that different coordination measures responded differentially to the situational demands. Time-based measures reveal changes in movement coordination in most body dimensions when transitioning to conflict. Frequency-based measures show differences in the higher frequency bands (1-2 Hz) for horizontal and vertical head motions. Correlations between conditions were found in the spatial domain, indicating dyad-specific, persistent levels of postural similarity. The results suggest a nuanced understanding of temporal coordination phenomena, highlighting the need to consider different nonverbal subsystems and distinct types of coordination.