Figure 1.
Sneezing is mainly triggered by stimulation of trigeminal sensory nerves in the nasal epithelium
The trigeminal nerves provide a sensory input to the “sneeze centre” in the medulla that triggers reflex activation of nasal and lacrimal glands to cause a rhinorrhoea, facial muscles to cause closure of the eyes and grimace, and respiratory muscles to cause inspiration followed by an explosive expiration.