Fig. 4

Mathematically controlled comparisons among the simple NFO, the activator-amplified NFO variant, the inhibitor-amplified NFO variant, and the type 1 incoherently-amplified NFO variant. Schematic representations and frequency-amplitude plots for the four oscillator models are presented for comparison. In these plots, the changes in the frequency and amplitude due to the perturbations are expressed as a ratio to the frequency and amplitude before the perturbations