Previous studies have demonstrated age-related deficits in implicit learning of higher order sequences in comparisons of college-age and elderly adults (e.g., J. H. Howard & D. V. Howard, 1997). This study examined whether these age deficits begin in middle age. Results showed a reliable age-related deficit in pattern sensitivity in "older" compared with "younger" middle-aged people, and age reliably predicted sensitivity to the sequence by using both speed and accuracy measures. The results are consistent with an age-related decline in a generic cognitive resource as reflected in T. A. Salthouse's (1996) simultaneity mechanism of cognitive aging.