In the Fmr1−/y genetic mouse model of FXS, absence of FMRP leads to impaired retinal signaling and visual perception in these mice, including altered retinal electrophysiological responses to stimuli as assessed by ERG [35, 40], deficits in contrast discrimination [41], reduction in the ability to translate a moving contrasted pattern [41], and impaired perspective perception [41]. The gene discussed is FMR1; the disease is fragile X syndrome.