Fig. 1.

Previously established second-order nonlinear Uryson model of the total baroreflex arc (17, 18). x[n] is the carotid sinus pressure (CSP) input; y[n] is the arterial pressure (AP) output; and k₀,k₁[n], and $k_2^D\left[n\right]$ are the zeroth-, first-, and second-order system kernels.