(
2007-03-30)
Homma, Ryota; Cohen, Lawrence B.; Kosmidis, E. K.; Youngentob, S. L.
We measured the concentration dependence of the ability of rats to identify odorants and
compared these results with the calcium signals in the nerve terminals of the olfactory receptor
neurons. Odorant identification remained far above random chance at all concentrations tested
(between 0.0006% and 35% of saturated vapor). In contrast the calcium signals were much
smaller than their maximum values at odorant concentrations less than 1% of saturated vapor.
Extrapolation suggests that only a few spikes in olfactory sensory neurons may be sufficient for
correct odorant identification.
