Figure 8. Refractive error of form-deprived right eyes and ungoggled left eyes from IRBP KO mice over time compared to eyes from naïve control mice. In all cases, the refractions remained the same at approximately −4 D (no significant differences on the Holm-Sidak test, p>0.05) regardless of age or the length of goggling. This suggests a ceiling effect, and that the role of the interphotoreceptor retinoid-binding protein (IRBP) is manifested in processes that precede focus- or form-dependent vision adjustments toward refractive growth.