It has been well documented in Chinese acupuncture medicine that "Hegu(LI 4) is indicated for orofacial problems".In the present paper

the authors analyze their correlation from the learning of modern medicine and results of recent experimental studies instead of traditional meridian theory of acupuncturology.The afferent nerve fibers from the LI 4 region and the orofacial part ascend to the spinal cord

nucleus of solitary tract

reticular formation

thalamus and the cerebral cortex

respectively

and overlap in the thalamus

cerebral cortex

etc.Under the circumstances

the interaction and functional integration of the afferent signals from LI 4 acupoint and the orofacial region may occur in the central nervous system.In addition

many relevant neuroactive substances(for example

serotonin

substance P

enkephalin

γ-aminobutyric acid

glycine

calcitonin gene-related peptide

etc.) released from the sensory and motor neurons in the corresponding cerebral regions may constitute part of the substantial basis of that "Hegu(LI 4) is indicated for many orofacial disorders".