Fig. 5. Stimulus domain as defined by power spectrum parameters. (A) Relative power at the high frequency flank (where the hump occurs) as a function of rms value. (B) Relative power at the rising edge at 100 Hz as a function of rms value. Note the flat curves obtained using resistive loads (red symbols). These curves and those obtained using capacitive loads (blue symbols) bound a domain in which are contained resistance—capacitance combinations (black filled symbols: in parallel). Note the different shape of plots A and B; for an explanation, see text. Data presented in Figs 4 and 5 were obtained from different animals.