Paying attention to time as one gets older

Age-related changes in attention and interval timing as a function of time of day were examined using a temporal bisection task with single and compou nd auditory, and visual stimuli. Half of the participants in each age group were tested in the morning, and half were tested in the afternoon. Duratio n judgments were found to be shorter for visual signals than for auditory, signals. This discrepancy was greater in the morning than in the afternoon and larger for the older than for the Younger adults. Young adults showed e qual sensitivity to signal duration for single and compound trials and high er sensitivity in the afternoon than in the morning for both signal modalit ies. In contrast, older adults showed impaired sensitivity on compound tria ls and the greatest sensitivity overall to single visual trials in the morn ing. These results suggest that age-related reductions in attentional resou rces may cause older adults to focus on signals that require controlled att ention during specific phases of the circadian cycle.