A 2012 study using functional magnetic resonance imaging (fMRI) showed that Acupuncture causes important changes in brain functional connectivity related to pain relief.
The study also indicated that Acupuncture produces significant decreases in the frequency of sciatica pain and pain intensity.
MRIs showed that Acupuncture triggered changes in the functional state of the brain, providing patients with greater resting states.
A total of 10 Acupuncture treatments were received by the participants in the study: twice a day, three times a week for a little under 2 weeks.
Participants in the study all had pain consistent with chronic sciatica diagnostic criteria for over 3 months: radiating pain over the sciatic nerve innervation area (e.g. buttocks, posterior upper leg, posterior lateral lower leg, lateral top of the foot).
Researchers in the study determined that Acupuncture regulates the default mode network (DMN), which correlated to significant reductions in sciatica pain.
The DMN is at its peak activity level when the brain is at rest and consists of a complex of interconnected activated and deactivated brain regions. This research reported that sciatica pain disturbs the normal DMN pattern, and that Acupuncture was able to restore it.
“..(Acupuncture) raises negative activation in the brain’s default mode network (DMN) of chronic sciatica patients, especially in the dorsal medial prefrontal cortex and anterior cingulate cortex.” (1)
The frontal cortex and cingulate cortex are involved in pain-related subjective cognition and perception, emotional responses, memory and attentional responses (2).
Raising negative activation in the DMN is associated with decreased pain, it is a form of functional connectivity present during the resting state of the brain (3).