Attentional bias modification (ABM) aims to attenuate social anxiety by directly modifying the underlying bias that generates and maintains problematic anxiety. Mixed results from previous ABM studies have spurred efforts to boost its effectiveness by introducing more robust bias modification protocols and new technologies. This thesis explored the effects of virtual reality (VR) based ABM training on attentional bias and social anxiety symptoms.

Study I investigated the efficacy of a single-session, VR based dot-probe task in reducing attentional bias and social anxiety symptoms. The results showed no significant differences between active and mock ABM training. No attentional bias was observed at baseline, and the dot-probe training did not alter attentional bias. The use of two-dimensional or three-dimensional stimuli had no significant impact on anxiety symptom or bias. Although we found an overall reduction in anxiety symptoms over time, this reduction was not specific to active training and the magnitude of change was not clinically significant. Study II examined the efficacy of a single-session, VR based person-identity-matching (PIM) task. The results were practically identical to those found in Study I, with no bias observed at baseline and no correlation observed between bias and anxiety. No change in attentional bias was observed post-training. For anxiety symptoms, participants showed a general reduction in their anxiety scores over time. Once again, this reduction was nonspecific and clinically insignificant. Overall, the empirical studies of the current thesis indicated no substantial treatment gains from a single session of VR based ABM. More accurate, reliable, and precise measures of attentional bias are needed before we can properly assess the efficacy of any ABM procedure. Study III took on a broader perspective by compiling and synthesising contemporary expert opinions on the use of virtual reality and mixed reality technologies in the treatment of anxiety and stress-related disorders, with a focus on the current state of technology-assisted psychotherapies and their prospective development. The experts acknowledged that current VR psychotherapies still face some challenges, but the consensus was that the overall outlook for future use of VR psychotherapies remained positive.