Explicit and Implicit Timing Across the Adult Lifespan

The study of whether temporal processing in the millisecond-to-seconds range changes with age is an active and debated research field. Here, we adopted a lifespan approach in which younger to older participants performed both explicit and implicit timing tasks (time bisection and foreperiod tasks, respectively) in a single session. Three hundred seven participants (age range: 20-85 years) took part in the study. Participants performed two timing tasks to test explicit and implicit time processing. Age was used as a continuous predictor to elucidate whether explicit and implicit temporal processing change with increasing age. The results from the explicit timing task showed reduced precision with age, as indexed by a flatter psychometric curve and greater just noticeable difference metrics. By contrast, implicit processing of time was not significantly affected by age, as evinced by a comparable foreperiod effect across age. These findings provide first adult lifespan evidence that only explicit, but not implicit, timing is sensitive to age-related changes.