Figure 8.

Relationship between the mean and SD of the neuronal discharge rate reveals why best threshold does not occur at the steepest slope. A, Mean rates, SDs, and model fits as functions of ILD for one neuron (CF, 16 kHz). Symbols and lines are as in Figure 1A. B, The slope of the rate, the SD, the ratio of the slope and SD, and the threshold ILD as functions of pedestal ILD for the neuron in A. Note that the ILD axis for this neuron has been slightly adjusted so that the rate slope maximum occurs at 0 dB ILD. The maximum ratio of slope and SD and thus, the best-threshold ILD, does not occur where the slope is maximal (point C in A), but at a point slightly contralateral (positive ILDs between B and C in A).