An electrical circuit model of chemoreceptor cells based on adaptation anddisadaptation time constants: implications for temporal filtering

Chemoreceptor cells have temporally dynamic physiological properties that s erve as filters for fluctuating odor patterns. A computational model, based on an electrical circuit, of a peripheral chemoreceptor cell was developed based on two time constants (tau(1) and tau(2)) that model sensory adaptat ion and recovery from adaptation. With tau(1) set to 0.1 s and tau(2) to 3. 8 s, our model receptor cell responded like real olfactory cells when prese nted with a series of odor pulse trains. As in real olfactory cells, change s in response magnitude and frequency filtering were observed with changes in stimulation frequency. When presented with chaotic stimulus patterns, mo del receptor cells responded with brief periods of current flow and adapted quickly. Decreases in the first time constant (tau(1)) decreased the respo nse magnitude, while decreases in the second time constant (tau(2)) increas ed the response magnitude and pulse frequency resolution during chaotic odo r stimulation. The two time constants are important for determining differe nt filter properties of the chemoreceptor cells and define the temporal ran ge of chemical fluctuations to which a single cell will respond. (C) 2000 E lsevier Science S.A. Ail rights reserved.