Two single parameter families of polyhedra P (ψ) are constructed in three dimensional spaces of constant curvature C(ψ). Identification of the faces of the polyhedra via isometries results in cone manifolds M(ψ) which are topologically S × S, S or singular S . The singular set of M(ψ) can have self intersections for some values of ψ and can also be the Whitehead link or form other configuration...

Transient tritanopia is a cone-cone post-receptoral interaction between short-wavelength (S) cones and medium (M) and long (L) wavelength cones. Blue cone monochromats have rods and S cones of normal sensitivity but lack functional M/L cones. All blue cone monochromats tested (n = 8) show significant amounts of transient tritanopia mediated by rods. Attempts to find a similar rod-S cone interac...

Proper functioning of sensory systems requires the generation of appropriate numbers and proportions of neuronal subtypes that encode distinct information. Perception of color relies on signals from multiple cone photoreceptor types. In cone-dominated retinas, each cone expresses a single opsin type with peak sensitivity to UV, long (L) (red), medium (M) (green), or short (S) (blue) wavelengths...

PURPOSE In the mammalian retina, rod and cone pathways are fundamentally intertwined, with signals from both converging on cone bipolar cells to reach retinal ganglion cells. Psychophysical and electrophysiological data suggests that, as a consequence, rod signal transduction has a suppressive effect on the activity of cone pathways. It therefore might be assumed that the balance between rod an...

PURPOSE The effect of increased numbers of S-cone photoreceptors in enhanced S-cone syndrome (ESCS) was investigated psychophysically in six ESCS observers to understand more about relative cone sensitivities and postreceptoral organization. METHODS Measures of temporal sensitivity or delay were made: S- and L-cone temporal acuity (critical flicker fusion, or CFF), S-cone temporal contrast se...

PURPOSE To assess the effect of preoperative topographic cone location on 1-year outcomes of corneal collagen cross-linking (CXL). METHODS In this prospective, randomized, controlled clinical trial, 99 eyes (66 keratoconus, 33 ectasia) from 76 patients underwent CXL. Cone location was defined by the coordinates of preoperative maximum keratometry (maximum K) using the anterior sagittal curvat...