Automatic imitation towards robots is not influenced by the intentional stance

Automatic imitation refers to the unconscious tendency to copy observed actions, a phenomenon that is robustly weaker when observing robots compared to humans. The present study investigated whether individual differences in the tendency to adopt the intentional stance (the epistemic strategy to attribute mental states to an agent or entity to predict/explain its behaviours) modulates this automatic imitation bias against robots. To do so, participants completed an online Automatic Imitation Task using both human and robotic hands, along with the Intentional Stance Test-2 (IST-2) and measures of attitudes and subjective perceptions towards robots. While our results successfully replicated the classic automatic imitation effect and the bias against robotic effectors, we found no significant relationship between IST-2 scores and the magnitude of the imitation bias. Bayesian analyses provided moderate evidence supporting the null hypothesis. Furthermore, exploratory measures regarding general attitudes towards robots and perceived anthropomorphism also failed to correlate with the imitation bias. These findings suggest that top-down beliefs regarding the intentionality of an agent do not modulate the interference effect. Instead, the attenuated imitation of robotic effectors appears to be primarily driven by bottom-up associative processes and the inherent visual and kinematic differences between human and robotic actions. More broadly, the results support that perception and action are tightly coupled through experience and indicate that individual differences in mental state attribution do not readily modulate low-level imitation mechanisms.