Effects of odorants and irritants on respiratory behavior.

A technique that combines psychophysical measurements with continuous recording of nasal patency and respiratory behavior was used to study the psychophysical and respiratory responses of 10 subjects to well-controlled stimulation with three compounds differing in relative stimulatory effectiveness for nasal olfactory and trigeminal chemoreceptors. All four concentrations of acetic acid, amyl acetate, and phenethyl alcohol were well above the odor detection threshold. The magnitudes of both the increase in odor strength and nasal irritation and the decreases in tidal volume were greatest for acetic acid and least for phenethyl alcohol. Among the odorants, differences in nasal irritation were greater than those in odor strength, and tidal volume appeared to have a reasonably close and inverse relationship to nasal irritation.