Pain as a multisensory warning system: testing its malleability and treatment

Research Questions:
We will investigate whether the development of bespoke, interactive and immersive virtual reality-based environments can be used as a clinical intervention for individuals experiencing chronic hand pain. The research will also provide necessary developments for furthering current understanding of chronic pain. We aim to answer two relevant questions:
1. Can we use VR and motion capture technology to change the experience of hand pain by modulating threat-related prior expectations and multisensory information?
2. Can these perception modulation interventions produce changes in the experience of pain which persist in time, resulting in better patient-reported outcomes, and therefore inform novel treatment interventions for chronic pain patients?

Methodology
The research project will develop a group of different immersive virtual reality-based upper-limb tasks to be used by clinicians or individuals experiencing naturally occurring pain. We will start by searching the literature in order to identify VR-based upper limb illusions tested in individuals with pain. Findings form the literature on VR-based upper-limb illusions will guide the development of the VR interventional applications, as well as systematic motion analysis. Unity, a cross-platform game engine software, will be used to develop the VR immersive environments and functional tasks. The development of these applications will be guided by important feedback from close networks with patient representative groups, GP practices and Hand surgery and therapy teams. In first instance, we envisage the following three experiments (A, B and C) which possess a between-group design:

- In experiment A, I will induce an offset between perceived wrist movement and visual feedback in pain-free individuals through the use of a VR headset and hand tracking technology (Leap Motion device), creating the impression that a participant's wrist is further (or not as far) rotated as it actually is and capturing the impact of the illusion on how individuals act upon objects through motion tracking. The control group will experience visual feedback in VR which has no offset between real and seen position.

- In experiment B, I will use the protocol outlined in experiment A to compare the results between a group of individuals experiencing an experimentally-induced pain (exercise-induced delayed-onset muscle soreness of the wrist DOMS) compared to a pain-free group. I will also test whether participants display further wrist rotation and experience less pain after the effect of the perceptual illusion has stopped. If modulating multisensory information about the wrist reduces prior expectations about threat to this body part, participants should increase wrist movement before pain is evoked. Such a finding would confirm perception as a target for VR-based interventions in this clinical population.

- In experiment C, I will compare the effectiveness of the protocol outlined in experiment B with a group of individuals experiencing chronic wrist pain, in a randomized controlled trial. The experimental group will experience wrist movement with an offset between perceived wrist movement and visual feedback. The control group will play a VR game involving interacting with objects but with real visual feedback