Age, Testing at Preferred or Nonpreferred Times (Testing Optimality), and False Memory

Two experiments investigated whether age and testing at preferred (optimal) times of day or nonpreferred (nonoptimal) times affected the ability to select relevant from irrelevant but thematically related alternatives in a verbal false memory paradigm. A 3rd experiment pursued the same issues with a visual false memory paradigm. In all 3 experiments, younger adults (n = 195) correctly recalled studied items more often than older adults (n = 121), whereas the 2 age groups correctly recognized about the same numbers of previously studied items. In all 3 experiments, nonoptimally tested older adults had more difficulty excluding nonstudied but thematically related items than the other groups; thus, they showed the greatest evidence of false memory, although all groups did so to a significant extent. The results suggest that optimality and its circadian determinants need to be considered with some tasks for the elderly. Various models and mechanisms are discussed.