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A nonlinear integral equation for visual impedance.

S M Berman·A L Stewart
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Abstract

The Hartline-Ratliff equation is a linear integral equation of the second kind and is employed in modeling inhibitory networks. Saturation of the inhibiting elements is commonly modeled as a function whose form is sigmoid; however, the resulting integral equation is nonlinear. Whenever the unknown function within the integral is hypothesized to be a nondecreasing nonlinear function, the Hartline-Ratliff equation becomes a nonlinear integral equation of the Hammerstein type. We present existence and uniqueness theorems for a Hammerstein equation which represents a further generalization of the Hartline-Ratliff equation.

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HumansMathematicsModels, NeurologicalNeural InhibitionSensory ThresholdsVision, OcularJournal ArticleResearch Support, U.S. Gov't, Non-P.H.S.

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S M Berman, A L Stewart. 1979-08-01. A nonlinear integral equation for visual impedance.. https://doi.org/10.1007/bf00337291

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