Brain-to-Brain Coupling Is Associated With the Benefits of Delayed Imitation in Skill Acquisition: An fNIRS Study

Purpose: Observational learning through imitation is an important ability across various domains. Although research has found that delayed imitation produces superior learning outcomes compared with other observational learning strategies, the underlying reason for this advantage remains unclear. This study investigated whether interpersonal brain synchronization (IBS) between learners and demonstrators is related to the benefits of delayed imitation. Methods: A total of 48 pairs of participants (M_age = 19.44, SD_age = 0.71) engaged in an abacus learning task under three learning conditions: observation without imitation, concurrent imitation, and delayed imitation. The brain activity of learners and demonstrators was simultaneously recorded using functional near-infrared spectroscopy. Results: Delayed imitation led to better learning outcomes than concurrent imitation across both skill operation performance and operational rules. However, performance in the delayed imitation condition did not differ significantly from that in the observation-only condition. At the neural level, delayed imitation elicited stronger IBS in the right dlPFC, with both observation and imitation phases contributing to this increased synchronization. Crucially, IBS in the right dlPFC was positively correlated with learning performance. Conclusions: These findings suggest that the advantage of delayed imitation is associated with enhanced brain-to-brain coupling between the demonstrator and the learner, providing novel evidence that interbrain coupling contributes to effective observational learning.