Experimental and Modeling Studies of Orientational Sensitivity of Neurons in the Lateral Geniculate Nucleus

Experimental studies have shown that the orientation selectivity of visual stimuli is characteristic not only of cortical, but also of subcortical neurons in the dorsal nucleus of the lateral geniculate body in cats. Mathematical modeling reported here provided an analysis of the factors affecting measures of the orientational selectivity of neurons. Simulated responses to bar stimuli and brightness gradient stimuli were qualitatively consistent with experimental results. Non-null coefficients of selectivity may result either from an elongated receptive field shape in conditions in which the influences of saturation effects are nonlinear or where the center of the receptive field is displaced relative to the center of the stimulus.