Olfactory analogue to directional hearing
The direction of a sound source can be determined binaurally by using the time difference and the loudness difference of the sound waves arriving at the two ears. Similarly, the direction of an olfactory source can be determined by using the time difference and the difference in sensation magnitude of the olfactory stimuli between the two nostrils as the air surrounding the odorous object is inhaled. Time differences of the order of 0.1 msec can be recognized—a value similar to that found in hearing. Thus the direction of an odor can be determined with a precision of 7–10° in spite of the small distance between the nostrils compared to the distance between the ears. In this respect, there is very little difference between observations made with such odorants as benzol, eucalyptus, cloves, and lavender. The existence of an analogy between hearing and smelling may help to delineate some electrophysiological correlates of the directional sensation, which is so well developed in both senses. localization of olfactory stimuli; interaction between the two nostrils during smelling; time pattern and olfactory localization; olfactory sensation magnitude and duration of stimulus; combination of smell and taste into a single sensation Submitted on November 1, 1963