Stepping into fear safely: A case study on mixed reality exposure in spider phobia.

Arachnophobia is a common specific phobia, yet access to therapy is limited. This single-case study examined the use of a mixed reality exposure therapy (MRET) for spider phobia, enabling room-aware spatial mapping and passthrough vision for safety. Its core feature is a spider behavior system that simulates naturalistic, unpredictable movements animated procedurally for ecological validity. The study participant was a 56-year-old female patient with chronic spider phobia who had shown limited response to two previous cognitive behavioral treatments. Progress was assessed at nine time points over one year using the Spider Phobia Questionnaire (SPQ), Fear of Spiders Questionnaire (FSQ), and Patient Health Questionnaire (PHQ-9). Results showed a 48% reduction in FSQ scores. Decreases in the SPQ avoidance and vigilance subscale scores were notable. MRET produced substantial and lasting reductions in spider phobia severity over a period of 12 months, with improved tolerance, reduced avoidance, and stable mood. The approach was well accepted.