Implicit learning of a nonverbal sequence in younger and older adults.

Two experiments examined age-related differences in implicit serial learning using the M. J. Nissen and P. Bullemer (1987) task. Younger adults and 2 samples of older adults who differed in educational attainment, occupational status, and verbal ability were given a 10-trial repeating sequence embedded in 100-trial blocks. On each trial, participants pressed a key that matched a designated spatial location. Implicit learning was inferred from the difference in RT between a random sequence trial block and the immediately preceding block with the repeating sequence. Results indicated that negative transfer effects were comparable for the younger and higher ability older adults, but lower ability older adults showed less evidence of implicit learning. On an explicit task, younger and higher ability older adults were more accurate than the lower ability older adults. The implications of these findings for current views on implicit learning in adulthood are discussed.