How learning influences smell

The smell of an odor is not merely a result of chemical detection but is also influenced by what the smeller learns about the odor. Now, researchers have discovered how such "perceptual learning" about an odor influences processing of information from the purely olfactory chemical detection system. Wen Li, Jay Gottfried, and colleagues at Northwestern University reported their findings with human subjects in the December 21, 2006, issue of the journal Neuron.