We are often taught that it is almost impossible to publish negative results. Yet, in this issue, Boccaccio, Lagostena, Hagen, and Menini (2006) have assembled a very impressive array of negative results that answer a critical question in olfactory transduction. In an elegant set of experiments, these authors have ruled out a suspected mechanism of fast olfactory adaptation and have, by default, provided further evidence for another mechanism in the process.
A characteristic feature of sensory transduction is adaptation to the stimulus. When we sit in chairs, we quickly cease to notice their existence; when we enter a bright room, we squint only briefly, as our photoreceptors quickly adapt. Our sense of smell also adapts rapidly to the sustained presence of an odor: a flower smells most intense when first put to the nose. The primary mechanism of olfactory transduction has largely been worked out...
