& Bosman, 1990). However, there has been limited research on the degree to which older adults can acquire new skills and retain those capabilities across time.
The purpose of the present chapter is to review the current literature on age-related differences in the retention of skills. The ultimate goal is to describe the current state of awareness about age-related differences in the retention of skills and to elucidate the areas in which knowledge and research are lacking. An aim of this chapter is to provide an impetus for future research in the area of skill retention and aging. As will become clear, there is a paucity of research in this area. The data that are available are drawn from laboratory tasks, primarily for pragmatic reasons. For an individual to achieve expertise in a variety of real-world tasks may require as long as 10 years ( Ericcson & Charness, 1994), thus making it difficult for researchers to study skill acquisition and retention over periods of disuse. Consequently, researchers have focused on the acquisition of skill for more constrained tasks and the subsequent retention of such skills. It is important to remember that the principles derived from laboratory studies of skill are applicable to real-world skilled behaviors ( Schneider, 1985). Moreover, laboratory tasks such as memory for items, visual search, tracking, and so on, are often components of skilled behaviors acquired outside the laboratory. Thus, although it is critical to understand skilled behaviors in their natural contexts, it is equally important to try to understand basic processes and principles through experimental control ( Fisk & Kirlik, this volume).
As the chapter is focused on the retention of skills, it is important to specify what is meant by a "skill." For the present purposes, Adams' ( 1987) definition will be adopted: "Skills . . . have three defining characteristics . . . 1. Skill is a wide behavioral domain . . . 2. Skill is learned . . . 3. Any behavior that has been called skilled involves combinations of cognitive, perceptual, and motor processes with different weights" (p. 42). Thus, the present focus on the retention of skills encompasses a broad array of different types of acquired aptitudes that vary in terms of their cognitive, perceptual, and motor components.
There has been a limited amount of research conducted on the retention of newly learned skills for older adults. However, there has been much research on the retention of knowledge and skills for younger adults (dating back to Ebbinghaus, 1964; see reviews by