Alleviating phantom limb pain
Following arm amputation, individuals report that they still perceive their missing limb which often manifests as an unpleasant or painful sensation. Phantom limb pain has been estimated to occur in up to 80% of amputees and therefore poses a significant medical problem. The unusual challenge that medical staff face in treating phantom limb pain is that the pain arises from a part of the body which no longer exists. Indeed, conventional pain management mostly results in incomplete relief. Over the last two decades, evidence has been mounting to suggest that phantom pain is associated with changes of body representation in the brain, triggered by amputation-dependent sensory-loss. Phantom pain is therefore a powerful model for studying both brain plasticity and pain.
We combine an array of neuroimaging techniques and behavioural paradigms to study the structural and functional brain correlates of phantom pain. Benefiting from this new knowledge, we use transcranial direct brain stimulation, which is a non-invasive brain stimulation technique, together with behavioural therapy to abolish maladaptive phantom pain representation. Based on this research, we hope to design a cost-effective clinically applicable neurorehabilitation approach for treating phantom pain. A secondary objective is to gain new knowledge about the relationship between plasticity and pain, which is currently presumed to be causal.
Makin TR, Scholz J, Henderson Slater D, Johansen-Berg H, Tracey I. (2015). Reassessing cortical reorganization in the primary sensorimotor cortex following arm amputation. Brain. 138:2140-6. doi:10.1093/brain/awv161
Makin, T. R., Scholz, J., Filippini, N., Henderson Slater, D., Tracey, I., & Johansen-Berg, H. (2013). Phantom pain is associated with preserved structure and function in the former hand area. Nature Communications, 4, 1570. doi:10.1038/ncomms2571.
Melvin Mezue & Irene Tracey, FMRIB Centre, University of Oxford
Heidi Johansen-Berg, FMRIB Centre, University of Oxford
Christian Beckmann, Donders Institute for Brain, Cognition and Behaviour, Radboud University
David Henderson-Slater, Oxford Centre for Enablement, Oxford University Hospitals (NHS)