Three experiments explored different schedules of retrieval practice in young adults, older adults, and individuals with dementia of the Alzheimer type. In each experiment, an initial acquisition phase was presented in which participants studied or attempted to retrieve response words to cues, followed by a later cued-recall test. Experiment 1 produced a benefit of expanded retrieval over equal-interval retrieval during acquisition, but this benefit was lost in final cued recall. In Experiments 2 and 3, participants received corrective feedback during acquisition and modified spacing schedules. There was again no evidence of a difference between expanded and equal-interval conditions in final cued recall. Discussion focuses on the potential benefits and costs of expanded retrieval on a theoretical and applied level.Keywords: aging, Alzheimer's disease, memory, retrievalThe advantage of spaced learning episodes over massed learning episodes is one of the most fundamental characteristics in learning (see, e.g., Crowder, 1976, Chapter 9). In the present study, we examine an extension of the spacing effect that has considerable potential for maximizing the benefits of spacing. Specifically, a particular type of spacing that expands the interval between learning episodes appears to afford an additional advantage over a spacing schedule that equally spaces the study episodes. For example, in learning the name of a new person just introduced, one might use an expanded practice schedule by retrieving the name at an interval of 15 s, 45 s, and 60 s, compared with an equally spaced practice of retrieving the name pair every 40 s. This particular type of spacing, referred to as expanded retrieval practice, has been extended to applied situations, including educational settings (e.g., Rea & Modigliani, 1985), and to individuals with memory impairments, such as individuals with early stage dementia of the Alzheimer's type (DAT; e.g., Camp, Foss, Stevens, & O'Hanlon, 1996).The goal of the present series of experiments is to explore the benefits of expanded retrieval in young adults, healthy older adults, and individuals with early stage DAT. First, we briefly review the empirical evidence for this phenomenon, the potential theoretical accounts, and why one might be especially interested in this procedure in these particular groups of individuals.
Evidence for Benefits of Expanded Over Equal-IntervalSpaced Retrieval Landauer and Bjork (1978) were the first to fully explore the benefits of expanded retrieval over equal-interval spacing in two controlled experiments. In their first experiment, participants were initially presented a deck of cards that included fictitious first and second names of individuals. We refer to this as the acquisition phase. For present purposes, we focus on the trials in which participants were first presented both the first and second names intact, followed at varying schedules of receiving cards with only the first name of the study pair as a retrieval cue for the second name. For example, in the ex...