Action Feedback Enables Novices to Implicitly Acquire Task Regularities from Experts During Joint Statistical Learning.

Joint statistical learning enables interacting individuals to form shared representations, but prior research has primarily focused on homogeneous dyads with equivalent expertise. Real-world interactions often involve knowledge asymmetries, yet it remains unclear how novices implicitly acquire statistical regularities from expert partners via sensorimotor signals. This study investigated whether novices can implicitly extract sequence regularities to enhance joint statistical learning and compared two candidate mechanisms, action feedback versus action visibility. Using a modified serial reaction time task across three experiments, we found that novices paired with trained experts exhibited significantly steeper declines in reaction time compared to those paired with pseudo-experts. Moreover, expert-paired novices demonstrated a pronounced quadratic trajectory, indicating sequence-specific learning. Experiment 2 revealed that the absence of immediate action feedback eliminated this sequence-specific interference effect in novices, highlighting the critical role of shared perceptual outcomes in the implicit transmission of task regularities. Conversely, Experiment 3 showed that the absence of visual access to the expert's physical movements attenuated neither the novices' general sequence acquisition nor their sequence-specific interference effect. These findings extend the Theory of Event Coding framework to asymmetric social contexts by demonstrating that effect-based coding, rather than direct kinematic observation, drives implicit behavioral facilitation in joint action.