Figure 4.

Diagram of the predicted effects of odor deprivation (left) and enrichment (right) according to the compensation/homeostasis hypothesis and induction/perceptual learning hypothesis on the olfactory mucosa, bulb, and behavior. Compensation makes no specific prediction about odor discrimination but this may necessarily be opposite to the predicted effects on detection based on bulbar neural circuits. Induction predicts greater detection under enrichment. Perceptual learning predicts greater discrimination under enrichment (see text for further explanation).