Odorant-Specific Spatial Patterns in Mucosal Activity Predict Perceptual Differences Among Odorants. Kent, Paul F., Steven L. Youngentob and Paul R. Sheehe. Department of Physiology, Department of Neurology, Department of Preventive Medicine, The Clinical Olfactory Research Center, SUNY Health Science Center, Syracuse, 750 East Adams Street, Syracuse, NY 13210.
APStracts 2:0193N, 1995.
SUMMARY AND CONCLUSIONS
1. Using operant techniques, rats were trained to differentially report (i.e., identify) the odorants propanol, carvone, citral, propyl acetate and ethylacetoacetate. Following acquisition training, the animals were tested using a 5x5 confusion matrix design. The results of the behavioral tests were used to measure the degree of perceptual dissimilarity between any pair of odorants. These dissimilarity measures were then subjected to multidimensional scaling analysis in order to establish a two-dimensional perceptual odor space for each rat. 2. At the completion of behavioral testing, the fluorescence changes in the dye di-4-ANEPPS were monitored on the rat's nasal septum and medial surface of the turbinates in response to the same odorants. For each mucosal surface a 6.0mm x 6.0mm area was sampled at 100 contiguous sites with a 10x10 photodiode array. 3. Formal statistical analysis indicated a highly significant predictive relationship between the relative position of an odorant's mucosal loci of maximal activity or "hot spot" and the relative position of the same odorant in a psychophysically determined perceptual odor space (F=15.6, P<0.001). 4. The results of this study suggest for the first time that odorant-induced mucosal activity patterns serve as the substrate for the perception of odorant quality.

Received 4 April 1995; accepted in final form 16 June 1995.
APS Manuscript Number J223-5.
Article publication pending J. Neurophysiol.
ISSN 1080-4757 Copyright 1995 The American Physiological Society.
Published in APStracts on 30 July 1995.