Aging-related foveal flicker sensitivity losses in normal observers

Photopic flicker sensitivity for healthy subjects over 60 years of age was compared with that of subjects in their 20s and 30s. The stimulus was achromatic and viewed foveally through a 2.0-mm artificial pupil which assured a constant pupil size in all subjects. As a group, older subjects had lower flicker sensitivity than younger subjects. This was found even when the retinal illuminance difference between age groups that arises from increased lens absorption in older adults was taken into account. The results indicate that a reduction in retinal illuminance with age cannot account for all the flicker sensitivity losses in older adults.