Figure 8.

Neuronal selectivity and kurtosis of the generator potential. a, The distribution of the generator potential is highly non-Gaussian. The dashed line represents the kurtosis expected for a Gaussian distribution [log₁₀(3)]. All data points lie above this value. b, The kurtosis of the generator potential is, as expected, related to the selectivity of the cell to the stimulus set. c, The kurtosis of the spike responses is much higher than that of the generator potential. Thus, spike responses are more selective than is the generator potential. d, The increase in kurtosis in the spike responses can be explained by the nonlinear transformation between generator potential and spikes. The plot shows that the kurtosis predicted by the model matches very well that of the data.