Abstract

Retinal disease often affects color vision, and one of the most common acquired color vision defects is the “blue defect,” in which performance is decreased for discriminations normally mediated by the short-wavelength-sensitive (SWS) cone pathways (reviewed by Pokorny & Smith, 1986). In recent years there has been considerable interest in the mechanisms underlying blue defects. Analysis of these mechanisms could result in a better understanding of the etiology of the diseases and development of tests useful for following patients and assessing the effectiveness of treatments. In particular it would be useful to know if SWS cones are selectively affected by photoreceptor degenerations. As compared to the long-wavelength-sensitive (LWS) and middle-wavelength-sensitive (MWS) cones, the SWS cones are morphologically distinct (Ahnelt, Kolb & Pflug, 1987), their membranes are more permeable to some molecules (DeMonasterio, Schein & McCrane, 1981), and their calcium metabolism may be more like that of rods (Zrenner, 1983).

© 1991 Optical Society of America