Abstract
In this study, we propose a mathematical model of fixation eye movements controlled by visual attention mechanisms to establish an index for quantitative evaluation of higher-order cognitive functions. It is known that Mean Square Displacement (MSD) profiles of fixation eye movements show a crossover phenomenon (Engbert & Kliegl. 2004), which indicates that multiple external factors contribute to control of movements. We formulated a model based on a hypothesis that stable gazing is controlled by rectifying retinal errors by drifts and microsaccades. Simulation results suggest that fractional Brownian motion and continuous feedback to correct gaze positions yield the MSD profile of fixation eye movements. Furthermore, microsaccades contribute to modulate the MSD profile during short-range lags.
