Whodunit? Ownership and User Experience in Co-Creation with Generative AI

Generative AI (GenAI) tools like ChatGPT are transforming how people approach creative and professional writing, shifting the role of AI from a passive assistant to an active co-creator. This study investigates how different modes of human–AI collaboration, user-initiated fine-tuning versus AI-initiated drafting, affect users' perceptions of ownership, creativity, self-efficacy, and technology acceptance across two distinct writing tasks: professional email and creative storytelling. Using a 2×2 experimental design (N=60), we find that initiating content creation fosters stronger feelings of ownership and often leads to higher perceived creativity and confidence. However, user acceptance remains stable across tasks and modes, suggesting broad baseline trust in GenAI tools. These findings highlight the psychological nuances of co-creating with AI and offer implications for GenAI systems that aim to support meaningful, empowering human-AI collaboration.