Encoding of pheromone intensity by dynamic activation of pheromone receptors

The perireceptor and receptor events in a model of the single olfactory receptor neuron of the male moth Antheraea polyphemus are studied. This first stage of signal transduction imposes limiting conditions on the amount of information the olfactory neuron can process. By employing basic concepts of information theory we compare the effectiveness of the odorant concentration coding in dependence on the level of temporal detail. We analyze two hypotheses, one in which the information is encoded in the average concentration of the activated receptors and the other in which it is encoded in its time-gradient. We show that each encoding scheme operates optimally at different levels of temporal resolution and discuss their biological meaning.