The Vagus Nerve: Bridging Mind, Body & Heart in the Treatment of Chronic Pain

In his thesis, The Vagus Nerve: Bridging Mind, Body, & Heart in the Treatment of Chronic Pain, Charles Ethan Paccione investigated whether short-term transcutaneous vagus nerve stimulation or meditative-based diaphragmatic breathing could aid in the management of fibromyalgia (i.e., chronic pain) and whether psychological distress mediates the relationship between vagal activity (i.e., heart rate variability, HRV) and experimental pain outcomes in those with chronic pain. Paccione and colleagues found that both active and sham (i.e., inactive) vagus nerve stimulation and meditative-based diaphragmatic breathing showed overall comparable effects on pain and vagal (HRV) activity for those with fibromyalgia; average pain decreased as short-term resting SDNN—a HRV parameter of overall autonomic regulatory function—increased in the entire population during treatment. The impact HRV has on evoked pain tolerance and intensity seems to be conveyed indirectly via psychological distress in those with chronic pain and does not differ by sex. These findings indicate that more research should be conducted on these interventions to offer clearer clinical recommendations for those with long-term pain.