Previous studies have shown that there are many common structures between the neural network of pain and memory

and the main structure in the pain network is also part of the memory network.Chronic pain is characterized by recurrent attacks and is associated with persistent ectopic impulse

which causes changes in synaptic structure and function based on nerve activity.These changes may induce long-term potentiation of synaptic transmission

and ultimately lead to changes in the central nervous system to produce"pain memory".Acupuncture is an effective method in treating chronic pain.It has been proven that acupuncture can affect the spinal cord dorsal horn

hippocampus

cingulate gyrus and other related areas.The possible mechanisms of action include opioid-induced analgesia

activation of glial cells

and the expression of brain derived neurotrophic factor(BDNF).In this study

we systematically review the brain structures

stage of"pain memory"and the mechanisms of acupuncture on synaptic plasticity in chronic pain.