Discrimination of odorants in the non-olfactory system: analysis of responses of the frog gustatory system to odorants by multidimensional scaling.

The ability of the bullfrog gustatory system to discriminate odorants was examined by the cross-adaptation technique. Application of various odorants to the tongue increased the frequency of impulses of the gustatory nerve. The magnitude of the response to the second odorant, after the response to the first odorant was adapted, varied greatly with combination of odorants. Analysis of data obtained by a multidimensional scaling suggests that the ability of the frog gustatory system to discriminate odorants is similar to that of the human olfactory system.