Adult age differences in controlled and automatic memory processing.

The memory performance of groups of younger, middle-aged, and older participants was tested on indirect and direct tests of word stem completion and on a process-dissociation task. As expected, on the direct tests of stem completion, older participants had lower scores than the younger and middle-aged groups. Age effects were also found on the indirect word completion test. The process-dissociation task allowed memory performance to be divided into controlled and automatic processing components. Estimates of automatic processing were comparable for the three groups, but there was an age effect for controlled processing, with the middle-aged and older groups differing from the younger group. These results confirm the findings of J. M. Jennings and L. L. Jacoby (1993) and suggest that the decline in conscious processing efficiency begins in middle age.