Figure 8. Different kinetic parameters give rise to different adaptation properties.

A. Left, input to the kinetics block used to measure F_k, consisting of impulses Δu added to a constant baseline input u(t). Middle, a four-state kinetics block from the Off pathway. Right, F_k at low and high contrast, and the high contrast F_k rescaled in amplitude. B. Same as A for a ganglion cell On pathway. C. The change in gain of the kinetics block in panel A between low and high contrast as a function of two parameters, fast inactivation, k_fi and fast recovery, k_fr. Both parameters were normalized by the mean activation rate, k_a. D. The change in the time constant of F_k at low and high contrast as a function of k_fi/k_a and k_fr/k_a. E. The change in shape of F_k as a function of k_fi/k_a and k_fr/k_a, computed as the area of positive values of F_k divided by the total area between the curve and zero. F. Different parameter values of k_fi/k_a and k_fr/k_a for different cell types.