You May Need a Nerve to Treat Pain
- The Neurobiological Rationale for Vagal Nerve Activation in Pain Management
The vagus nerve is known for its cardinal role in controlling parasympathetic activity (rest and digest).
However, besides its efferent role the vagus nerve has an important afferent role as well: it informs the
brain of peripheral ‘events’ like infections. This (often ignored) role of the vagus nerve is sometimes
referred to as the motor vagus. Yori Gidron, professor in neuropsychoimmunology at the Vrije Universiteit Brussel,
is a world expert on the role of vagus nerve in (the treatment) of chronic illness, including cancer
(e.g. http://www.ncbi.nlm.nih.gov/pubmed/24026706).
He collaborates with Pain in Motion for studying heart rate variability in relation to central sensitization pain
(e.g.
http://www.painphysicianjournal.com/2013/may/2013;16;E277-E285.pdf) and for the study of psychological inoculation
for the treatment of chronic whiplash pain.
Marijke De Couck (picture) is a PhD researcher, working with Yori Gidron
on the role of the vagus nerve in cancer. Together they are innovating in the fast developing world of cancer prevention and treatment.
Pain in Motion is happy that Marijke and Yori were willing to dedicate some of their valuable time to the study of the (possible) role
of the vagus nerve for the understanding and treatment of (chronic) pain. This has led to the publication of a state-of-the-art article
on the role of the vagus nerve in (the treatment of) pain published by the Clinical Journal of Pain
(http://www.ncbi.nlm.nih.gov/pubmed/24451632).
Marijke and Yori studied the following question: Can there be one therapeutic pathway which may target multiple etiologic
factors in pain? And if so, can the vagus nerve have a role in such therapeutic pathway?
The paper reviews the evidence for the relationships between vagal nerve activity and pain, and between vagal nerve activity
and five factors which are etiologic to or protective for (chronic) pain. The five factors are:
vagal nerve activity inhibits inflammation, oxidative stress and sympathetic activity,
activates brain regions that can oppose the brain "pain matrix",
and finally it might influence the analgesic effects of opioids.
Together, the five factors can explain the analgesic effects of vagal nerve activation or administration of acetylcholine,
the principal vagal nerve neurotransmitter. Given the evidence and effects of the vagus nerve activation in pain,
clinicians active in pain therapy may want to consider therapeutic activation of this nerve as a new way of treating pain.