Coding of chemosensory stimulus mixtures.
It appears likely that substantial processing of odor mixtures is done by peripheral olfactory structures. Both physiological and psychophysical data suggest that the first step is differential adsorption of constituents by the olfactory mucus, which separates and concentrates constituents in epithelial regions where neurons are most responsive to them. The second step involves the diffusion of adsorbed odorants through the mucus and activation of the receptor neurons. In contrast to the minute times involved in the first step, the time taken to diffuse through the layer and stimulate neurons is large, varies markedly between odorants, and is concentration dependent. The second step, therefore, provides another process for separating the actions of individual odorants. Both processes either separately or combined can account for mixture phenomena such as suppression and masking. Defining the role of each process with different mixtures of odorants that have different molecular properties is clearly a goal for future studies.
Laing
D G
DG
CSIRO Division of Food Research, Food Research Laboratory, North Ryde, N.S.W., Australia 2113.
D000818:Animals; D006801:Humans; D009812:Odorants; D011984:Sensory Receptor Cells / Q000502:physiology*; D012903:Smell / Q000502:physiology*