Aging and judgments of duration: effects of task complexity and method of estimation.

The effects of aging on judgments of short temporal durations were explored using the prospective paradigm and the methods of verbal estimation and production. Younger and older adults performed a perceptual judgment task at five levels of complexity for periods of 30, 60, and 120 sec. Participants either continued to perform the task for a specified interval (production) or were stopped and then verbally estimated the interval. Older adults gave shorter verbal estimates and longer productions than did younger adults. The methods of verbal estimation and production yielded approximately equal duration judgment ratios once range effects were taken into account. Task complexity had little effect. The major conclusion is that duration judgment ratios decrease from younger to older adults when the intervals are filled with a mental task.