Design and Evaluation of an Immersive VR Space Based on Pedagogical Agent for Theory of Mind Training in Autistic Children: Insights from Brain Activity and Participatory Study

Virtual reality (VR) is widely recognized as a promising tool for social intervention in children with Autism Spectrum Disorder (ASD) However, it remains unclear how the design of virtual social partners shown in VR systems is optimized for the neural and behavioral responses in young children with ASD. The implementation pathway and intervention effects of VR spaces also need validation through empirical research. This study employed a mixed-methods approach, combining neural imaging experiment, qualitative inquiry, and participatory design to develop an immersive VR intervention space. Twenty-two autistic children (aged 3-8) completed theory of mind (ToM) tasks with virtual characters varying in anthropomorphism and interaction complexity. Neural activation was measured in brain regions related to mentalizing. Stakeholder preferences were gathered via interviews with clinical experts and collage workshops with autistic children. Results showed that virtual characters with rich interaction and low anthropomorphism elicited greater neural responses in children with ASD. Participatory design revealed children’s preferences for cartoon-style characters with expressive voices, simple verbal expressions, moderate facial expressions, and muted colors. A VR intervention space was designed and developed. Therapists reported a high score of usability, and caregivers reported improvements in children’s social skills. This study is the first to combine neuroimaging evidences with stakeholder-informed participatory design workshops to investigate autistic children’s preferences for virtual characters, and thereby design optimized VR-based intervention system. The interventional effectiveness was proved by both clinical experts and long-term training. This study provides theoretical and practical guidance for designing VR-based social interventions for autistic children.