How the Body Works: The Olfactory Pathway

Air inhaled through the nose passes over the olfactory membranes, where chemicals that are in the air stimulate the numerous olfactory receptor cells. The smell information passes from the receptor-cell neurons to the bulbs and tracts of the first cranial nerve, which pass into the frontal lobes of the brain. Each tract divides into medial and lateral striae, which pass the information to the olfactory cortex, where smell is perceived.