Genuinely olfactory preferences conditioned by protein repletion

Abstract

Effects of protein on mild food deprivation in the rat conditioned a relative preference for an intense, insoluble and tasteless odorant. This learned preference for the protein-paired odorant over a non-nutritive-paired odorant was temporarily obliterated by insertion of tubes in the nares to bypass the olfactory mucosa. This demonstrates truly olfactory conditioning, contrary to assertions that gustatory conditioning had not been excluded.