Odor-reward learning and enrichment have similar effects on odor perception.

We compared the respective effects of odor enrichment and reward-driven discrimination learning on the perception of odors. Experimental rats were exposed to two odorants for 1-h periods once daily over 10 days, or trained with the same two odorants in a forced-choice discrimination task during a daily 20 trial session over 10 days. Spontaneous discriminations between pairs of chemically similar odors were tested before and after the odor enrichment period using an olfactory habituation/discrimination task. We found that both enrichment and discrimination learning improved the subsequent perception of other, chemically unrelated odorants in similar manners. These results show that odor experience, whether passive or active, changes perception in the manner predicted based on other groups' electrophysiological experiments.