Does a yellow filter improve visual object categorization in normal aging?

Previous studies have shown that a yellow filter (CPF450) can increase contrast, motion sensitivity, vergence, and accommodation. We investigated whether a yellow filter can reduce age-related visual deficits. We tested two groups of 60 observers (mean age 24 vs. 72) in an object categorization task. Grayscale photographs of natural objects and artifacts were displayed either centrally or peripherally (21°) at low (8%) or medium (30%) contrast. There were three filter conditions (no filter, placebo filter, and yellow filter). Both groups of observers performed similarly on central and medium-contrast pictures. The deleterious effects of reduced contrast and eccentricity were stronger in elderly individuals. Moreover, the yellow filter globally improved the speed of categorization for the elderly participants. The decrease in response time in the yellow filter condition was larger when the stimuli were displayed peripherally in both groups. A yellow filter should be considered as a potential means for visual improvement in normal aging.