Files in this Data Supplement:
Fig. S1. Slope of the neurometric function. (A) Estimates of the threshold and slope of the neurometric function improved with increasing numbers of trials. The left panels show the mean and standard deviation of the posterior density function calculated with the slope (β) of the Weibull neurometric function set to 0.05 based on pilot data. The right panel show, for the same fly, the mean and standard deviation of the slope value that would maximize the mode of the posterior density function, a measure of goodness of fit. Data for responses at the stimulus frequency (F0, solid lines) are plotted separately from those at the second harmonic (F1, dashed lines). Crosses mark points at which the standard deviation of the threshold estimate drops to 3 dB. (B) For 11 females, estimated slope values for both F0 (open circles) and F1 (filled circles) were smallest for those that had the smallest standard deviation. Data points shown in A are in blue. The horizontal and vertical black dashed lines in A and B indicate the pilot-derived slope value of 0.05. (C) The Weibull neurometric function with β=0.05, δ=0.01 and γ=0.5 is shown in black. Red curves are for values of β corresponding to the average of the estimated slope values with standard deviations less than 1.0: solid is for F0 (β=0.067), dashed is for F1 (β=0.109).
Fig. S2. Sustained deflections in Johnston�s organ of a female Drosophila (red) and the mosquito Aedes aegypti blue; from Cator et al. (Cator et al., 2009). Stimuli were 400 Hz tones at 107 dB in the fruit flies and 115 dB in the mosquito. Note the greater voltage scale for the mosquito.
