Nasal responses to local unilateral stimuli in man

The present study was designed to test the hypothesis that a feedback loop relaying information on the patency of one nasal cavity might be processed by the central nervous system to modify the vascular engorgement of the other, thereby minimizing total airflow resistance alterations during the nasal cycle. Histamine and xylometazoline were used to alter the degree of mucosal swelling and a cotton plug to alter airflow, in one nasal cavity and resistance measurements were made from its fellow. No changes in the latter were observed. It was concluded that this feedback arc does not exist.