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

ABSTRACT

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.

Keywords:

• Normal aging
• Yellow filter
• Categorization
• Contrast
• Eccentricity

The authors would like to thank the participants in this study and Ken Knoblauch for his helpful comments on an earlier draft of the paper. This work was supported by funds from the Fondation pour la Recherche Médicale (FRM DLC 2006), obtained by Hélène Amiéva and Sandrine Delord, and by a grant from the French National Research Agency (ANR Advise) issued to Muriel Boucart and Sandrine Delord.

Notes

2. ¹Usually, analysis of both dependent variables allow to evaluate a speed-accuracy trade-off (SATO), frequent in normal aging that has been interpreted as the use of a more cautious response strategy in old people in order to avoid error commission or to compensate for decreased cognitive control. In the present study, task instruction mention to respond as precisely and as quickly as possible, that is both accuracy and speed were emphasized, although it has been shown that time or accuracy pressures did not prevent the occurrence of a SATO effect (Endrass, Schreiber, & Kathmann, 2012; Ratcliff, Thapar, & McKoon, 2007).