purpose: to evaluate the effect of vertical prism induced stress on binocular visual evoked potentials. methods: using checkerboard stimulus patterns in two spatial frequencies (sfs) of 0.48 cpd as a low sf and 2.18 cpd as a moderate sf reversing with temporal frequency of 4 hz, the effect of increasing visual stress using vertical prisms of 0, 1, 2 and 3 prism diopters on binocular visual evok...