Parallel cascade analysis of Phycomyces light-growth response

In the framework of the Wiener theory of nonlinear system identification, the authors have applied the parallel-cascade method, developed by M.J. Korenberg (Am. Biomed. Eng., vol. 19, p. 429-55, 1991), to the transient light-growth response of the zygomycete fungus Phycomyces. This response, in which the elongation rate of the fruiting body or sporangiophore is modulated by light, was previously studied by the Lee-Schetzen cross-correlation method and the related sum-of-sinusoids method. Examples are shown of first- and second-order kernels obtained by the parallel-cascade method applied to experiments with Gaussian white noise test stimuli.