Nonlinearities of the human ERG reflected by Wiener kernels.

The Electroretinograms (ERGs) of three subjects were represented by first- and second-order Wiener kernels using the analytical procedures previously reported for lower vertebrate (Marmarelis and Naka, 1973) and invertebrate (McCann, 1974) retinal studies. The variances between the kernel estimates were relatively small, yet the second-order kernels were relatively large. The significance of the nonlinearities reflected by each second-order kernel was assessed by comparing the predicted response to the white-noise stimulus obtained using a first-order kernel with that obtained using a second-order kernel.