Electroantennogram stimulus-response curves for 59 odourants in the honey bee, Apis mellifica

The dynamic responses of honey bee workers ( Apis mellifica ligustica) to 59 odourants were recorded at six different concentrations. About two-thirds of the odourants elicited the commonly observed negative electroantennograms, though two gave positive results. The other odourants elicited both positive and negative phases. The electroantennogram measurement defined by the absolute sum of the positive and negative amplitudes was a power function of the stimulus concentration, described by the Hill equation. In addition, the electrophysiological threshold, defined as the concentration yielding an electroantennogram of 0.1 mV, was correlated with the exponent of the power function, as found in human psychophysics. A highly significant correlation, also observed between the three parameters of the Hill equation, strongly suggests that two independent parameters are sufficient to reflect the diversity of the experimental curves. Finally, both correlations were improved by expressing odourant concentrations in terms of partial saturated vapour pressure. These results make it possible to further develop a theoretical model of olfactory stimulus-response relationships based on their underlying neurophysiological mechanisms. This work was presented in condensed form by Patte et al. (J. Physiol. Paris 79, 67A, 1984).