Impact of the aging process on event-,time-, and activity-based prospective memory

The present study aimed to compare the impact of the aging process on event-, time-, and activity-based prospective memory (PM) and to explore the aging patterns of PM-related cognitive functions. Seventy-five participants were recruited and divided into three age groups: young (20-24 years old), young-old (60-70 years old), and older-old (greater than 70 years old). A computerized PM test and a set of tests capturing executive functions, retrospective memory, and working memory were administered to all participants. Significant age effects were only found for event-based PM and time- based PM. However, event- based PM was noted to decline gradually, whereas time-based PM was noted to deteriorate abruptly with age. For older, but not young participants, performance on the time-based PM tasks was significantly improved under a more lenient scoring criterion which had an increased response time window. Measures of executive functions and retrospective memory were significantly associated with PM, but these relations disappeared after controlling for age and education. Working memory was found to be the most important contributor to the effect of age on PM. These findings suggest a differential aging process for event-, time-, and activity-based PM.