An investigation of age differences in backward monoptic visual noise masking was carried out with young and old adult subjects. It was found that the older subjects were susceptible to the backward masking effect over significantly longer delays between the target and masking stimulus. The masking effect seems to be, at least in part, attributable to age changes in the central mechanisms concerned with perceptual processing which limit the rate at which stimuli can be "cleared" through the nervous system. Backward masking studies of different types seem to hold considerable promise for assessment of the peripheral and central components of age change in visual perceptual processing.