Recent advances and future prospects in neuroimaging of acute and chronic pain

Abstract

The advent of modern functional brain imaging has created new possibilities for exploring the brain mechanisms that underly acute and chronic pain. It is now possible to explore how specific aspects of the pain experience are represented in the brain and the impact of individual attributes on these representations. This review provides an overview of the capabilities of positron emission tomography and functional magnetic resonance imaging and their utility in identifying pain-evoked forebrain responses in both acute and chronic pain conditions. Also presented are sophisticated approaches to the design and implementation of such studies, with the ability to isolate cortical responses related to specific pain constructs, the complexities of interpreting hemodynamic-based responses in consideration of the underlying neurophysiology and the impact of imaging pain for diagnostic considerations. Finally, it is predicted that the ability to identify functional brain abnormalities will challenge classical boundaries between neurology, gastroenterology and psychiatry.

Keywords::

• allodynia
• fMRI
• functional
• hyperalgesia
• neuroimaging
• pain
• perception
• PET

Acknowledgements

These studies were funded by the Canadian Institutes of Health Research, Ontario Mental Health Foundation and the Canada Research Chair Program. The author is a Canada Research Chair in Brain and Behavior. The author would like to thank Jonathan Downar, Chun L Kwan, David Seminowicz, Keri Taylor and Geoff Pope for their scientific and technical contributions.