Chronic pain is a major cause of disability that can often poorly managed with pharmacological treatments. This has prompted the exploration of other interventions like resizing illusions of body parts in augmented reality. These illusions have shown promise in conditions like osteoarthritis and complex regional pain syndrome, but it remains unclear how they alter the neural representation of body parts in the brain. The study by Hansford and colleagues aims to investigate these mechanisms in healthy participants, using somatosensory steady state evoked potentials (SSEP) and self-report questionnaires.

 

The study will involve finger stretching in an augmented reality setup that allows the researchers to independently manipulate visual and tactical stimulation. Assuming that multisensory stimulation indeed produces a robust illusion, the researchers will quantify the somatosensory evoked potentials in multisensory, unisensory, and two non-illusion control conditions. The study will provide inights into the neural mechanisms of these illusions and lay the ground for future investigations of these processes as a potential treatment for chronic pain.

 

The manuscript was evaluated over seven rounds of in-depth review by the recommender and three expert reviewers. After substantial revisions, the recommender judged that the manuscript met the Stage 1 criteria and awarded in-principle acceptance (IPA).

 

URL to the preregistered Stage 1 protocol: https://osf.io/u6gsb
 
Level of bias control achieved: Level 6. No part of the data or evidence that will be used to answer the research question yet exists and no part will be generated until after IPA.
 
List of eligible PCI RR-friendly journals:
 

References
 
1. Hansford, K. J., Baker, D. H., McKenzie, K. J., & Preston, C. E. J. (2023). Somatosensory Response Changes During Illusory Finger Stretching. In principle acceptance of Version 7 by Peer Community in Registered Reports. https://osf.io/u6gsb