| As part of a continuing effort to understand olfactory processing in rats, the correlations among odorant properties and their evoked neural and perceptual responses were examined within that species. Neural representations of individual odorants in the olfactory bulb were indicated by the level of [14C]2-deoxyglucose uptake measured throughout the glomerular layer, whereas perceived odor similarity was assessed using an odor habituation paradigm. Even though some hydrocarbon odorants have only weak steric interactions with olfactory receptors, unique combinatorial representations of individual odorants were observed to be organized chemotopically in the glomerular layer. Moreover, odorant-evoked neural and perceptual responses were strongly correlated, suggesting a close and predictable relationship across different stages of odor processing. Finally, the results here demonstrated that while the olfactory system was sufficiently sensitive to detect and discriminate even minor changes in odorants, it did not respond equally to all aspects of odorant chemistry, functioning as a specific, rather than a general chemical analysis system. |
