The proposed studies will use behavioral and anatomical methods to examine potential mechanisms of odor quality coding at the level of the olfactory bulb in rats. Because perception of odor quality cannot be assessed using traditional odor detection and odor discrimination tasks, we propose using more sophisticated methods that allow rats to report on their recognition of individual components of a homologous series of odors (a recognition test using odor memory) and their classification of novel odors from different homologous series (a modified odor generalization test). The extent to which odor quality coding depends upon a discrete odotopic map will be assessed by testing rats with selective aspiration lesions or selective olfactotoxin-induced deafferentation of the bulb on odor recognition tasks. Behavior tasks will use precision olfactometry. Anterograde transport of horseradish peroxidase will be used to assess connections between the olfactory epithelium and olfactory bulb in experimental rats.
