How can acupuncture or heat treatment affect pain signals?

Acupuncture and heat treatment are believed to affect pain signals through a mechanism involving the stimulation of peripheral nerve endings, which exerts an inhibitory effect on the nerve fibers responsible for generating pain.1

This process is consistent with the physiological understanding that the perception of pain can be modulated by neural mechanisms. By stimulating nearby nerve endings—such as through pressure, rubbing, or thermal stimuli—the transmission of pain signals through the nervous system can be inhibited. Furthermore, research into the thermal grill illusion indicates that thermal stimuli, such as cold or warm packs, interact with pain sensation through central neural mechanisms in the brain, rather than acting solely on the periphery.123

While acupuncture is an ancient technique designed to balance the body's life force, or qi, by affecting the distribution of yin and yang, its potential for pain relief is often discussed in the context of these inhibitory physiological pathways.41