Hummel, ThomasTechnical University of Dresden Medical School
Author
Abstract
The nasal mucosa through the intranasal trigeminal nerve is a full sensory organ, functionally organized and responsible for both the nasal patency perception and the chemosensory perception and also responsible to a certain degree for nasal inflammation. The primary function of the intranasal trigeminal system is to protect the upper and lower airways for potential life-threatening substances acting as a sentinel to shorten or stop inspiration reflexively. Besides this protective somatosensory function, the intranasal trigeminal system also helps to the global chemosensory perception with the olfactory system. Indeed, most of the odorants stimulate the neural olfactory and intrananasal trigeminal systems. Finally, the intranasal trigeminal system is also capable of inducing a neurogenic inflammation mainly through an axon reflex located in the subepithelial level of the nasal mucosa. The olfactory (cranial nerve I) and the trigeminal (cranial nerve V) systems interact at different levels and this interaction is essential for the odor sensation (Cain and Murphy 1980). The olfactory system is more dedicated in identification task for hedonicity and alimentary behavioral, recognition and memory, behavioral and social comportments than the trigeminal system probably more oriented to protective function and reflexes.