ISSN:
1432-1351
Keywords:
Chemoreceptor
;
Sensory adaptation
;
Lobster
;
Glutamate receptor cell
;
Signal-to-background ratio
Source:
Springer Online Journal Archives 1860-2000
Topics:
Biology
,
Medicine
Notes:
Summary and conclusion 1. We determined the time course of cumulative adaptation, e.g. the recovery from the effects of prior stimulation, in 127 glutamate-sensitive chemoreceptor cells in extracellular recordings from the walking legs of the lobster, Homarus americanus. 2. Interstimulus intervals of 5 s, 10 s, or 20 s did not affect the degree of cumulative adaptation of glutamate sensitive cells as a population. Cumulative adaptation represents a change in state rather than a gradual process. Individual cells revealed great diversity in the time course of cumulative adaptation, regardless of interstimulus interval. 3. Various combinations of high and low glutamate backgrounds and stimulus intensities showed that the stimulus-to-background ratio did not determine the time course of cumulative adaptation. 4. Low response magnitudes, regardless of what caused them, resulted in less cumulative adaptation. 5. Since cumulative adaptation was independent from background adaptation, underlying cellular mechanisms may be different. 6. Cumulative adaptation reduces the cell's response variability and might therefore enhance the temporal resolving power of single cells. 7. The rates of adaptation and disadaptation determine the temporal filter properties of a cell. Background adaptation keeps a cell in a working range where instantaneous (chemical) contrast can be measured.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1007/BF00187334
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