Fig. 5. Pheromone responses are dose-dependent. Stimulation with a solvent-loaded filter paper (control) did not elicit a measurable sensillar potential. The action potentials of the small class occurred at random. Stimulations with increasing doses of bombykal (BAL) elicited sensillar potentials of increasing amplitude, together with large action potentials at increasing frequency and shorter latency. At stimulus loads of 10^–2 µg, the reduction of the action potential amplitude during the response became obvious. The stimulus duration was 50 ms and stimuli were applied in increasing order, separated by intervals of 60 s (dose ramp).