In this chapter we explore possible adulthood changes in the contributions of knowledge to acquisition of new information into memory (episodic memory). In particular, we are interested in the ways that prior knowledge may compensate for a loss of processing resources associated with increasing age. We begin with the assumption that there is a decline in the efficiency of cognitive resources with increasing age. Although this assumption is not universally accepted, there is much evidence of age deficits on tasks varying in range of complexity from simple reaction time (see Salthouse, 1985a) to complex problem solving (e.g., Denney, 1982). In the area of memory, recent research has been directed at characterizing these declines. Alternatives commonly discussed include a loss of processing speed (Salthouse, 1985b), reduction in attentional resources (Craik & Byrd, 1982), deficit in retrieval (Burke & Light, 1981), and reductions in information-processing capacity (Hasher & Zacks, 1979).

In this chapter we describe memory tasks in which age deficits are commonly observed and discuss when and how prior knowledge seems to compensate at least partially for loss of processing resources. We suggest that equalization of prior knowledge of materials tends to ameliorate, but not eliminate, age differences in memory performance. We attempt to specify when variables related to knowledge would or would not be expected to reduce age differences. The review does not cover all aspects of memory. Instead, it focuses on episodic memory.