Ocular fixation index and mathematical models

A first attempt is presented toward a model interpretation of ocular interpretation of Ocular Fixation Index (OFI)By using simple mathematical models, the hypothesis is tested that visual suppression of vestibular nystagmus results from direct action of smooth-pursuit system (SPS). Consequences and limits of this hypothesis are discussed,and the dependence of OFI on SPS performance is examined. Although the available experimental data are insufficient for comprehensive validation of the model, simulation results agree with the current interpretations and quantitative support is provided to the sensitivity of OFI to central vestibular diseases.