The learning of linear and nonlinear functions in younger and older adults.

The performance of 192 adults in a functional learning task containing four types of cue-criterion relations-direct, inverse, U-shaped, and inverse-U-shaped-was compared. The ability of these adults at extrapolating learning to situations containing more extreme values than the ones in which it took place was also examined. Older participants (65-90-year-olds) were able to learn the nonlinear functions practically as well as younger participants (18-25- and 40-50-year-olds); they were also able to extrapolate well beyond the range of learned responses. When extrapolating, however, they frequently used a more limited range of responses than the younger participants.