Playful engagement in metacognitive reflection emerges through the interaction of curiosity and gamification structure

Digital systems structure how users engage with cognitively demanding, ambiguity-rich activities. While gamification is often used to support engagement, little is known about how differing forms of interactional structure shape playful experiences in such contexts. This study examined how interactional structure in gamified designs influences playful engagement during metacognitive reflection and how this relationship is moderated by trait curiosity. A between-subjects experiment was conducted with 86 undergraduate students using two gamified designs that differed in their degree of interactional structure (ludus and paidia) alongside a non-gamified control condition. Playful experiences and trait curiosity were measured using validated surveys, and general linear models examined condition effects and Condition × Curiosity interactions. The results showed no main effect of gamification condition on playful experiences. However, curiosity moderated playful experiences only in the structured gamification condition, particularly for expression and fellowship. No such relationships were observed in the open-ended condition. These findings suggest that playful engagement in reflective tasks may emerge from the interaction of design structure and learner disposition, rather than through gamification alone. Interactional structure may enable curiosity to translate into playful engagement, highlighting the importance of aligning system design, user dispositions, and task demands when designing for playful experiences.