the visual pathway that lies outside of, and is phylogenetically older than, the primary visual system. Retinal input travels directly to the superior colliculus and then to visual nuclei in the thalamus other than the lateral geniculate nucleus (i.e., the pulvinar and lateral posterior nucleus) before terminating in the prestriate cortex. The vision supported by the secondary visual system is relatively poor for the detection of form but allows localization and detection of movement. It functions relatively well in the newborn. See also blindsight.