ABSTRACT
There is a large body of scientific evidence, as well as a great deal of anecdotal, self-report data, suggesting that as people age, they are not as mentally “sharp” as they used to be. In a seminal paper on the topic of aging and memory, Craik and Byrd (1982) suggested that with increasing age, the amount of mental energy or cognitive reserves available to perform mental operations declines. According to Craik and Byrd, this reduction in attentional resources (also termed processing resources) accounts for many of the age-related declines observed on a broad range of memory tasks, particularly those tasks that require a great deal of mental effort or “self-initiated processing” (p. 203). Craik and Byrd suggested that there are conditions under which memory tasks can be highly supported (e.g., recognition), and that under these conditions, age differences in memory are smaller. Various types of environmental support can repair some of the memory declines resulting from diminished processing resources that occur with age. Implicit in this view of decreased mental energy with age is the assumption that individuals may vary in the amount of energy or processing resources that they have and that, presumably, individuals with more resources will perform better on memory tasks. Craik, Byrd, and Swanson (1987), in an early study, investigated this individual differences approach to processing resources. They compared the memories of three groups of elderly people who presumably varied in processing resources to those of young adults. They reported that healthy, engaged, high-income adults had performance most similar to young adults, that low income but engaged older adults were intermediate in their cognitive performance, and that older individuals who were both low in income and activities performed most poorly. There was also evidence that memory function was modulated by type of task and the amount of environmental support that it offered. They argued that these findings supported the notion of modulation of aging effects by environmental support and the quantity of processing resources an individual possessed.
