Age-Related Increases in the Effects of Automatic Semantic Activation

Automatic semantic activation was assessed in a version of the flanker task, in which nominally irrelevant words were presented above and below a target word. The category membership of the flanking word was consistent, inconsistent, or neutral with respect to the target word. Older adults showed greater inhibition and equivalent facilitation in the time taken to classify the target words than did younger adults in 2 of 3 experiments, in contrast to previous findings. The present results are generally consistent with 3 dominant perspectives in cognitive aging: the complexity hypothesis, environmental support, and the inhibition-deficit view. Manipulation of the overall magnitude of the flanker effect produced results most consistent with the inhibition-deficit view that older adults are less able to inhibit automatic processes than are younger adults. Some problems with the inhibition-deficit view are also discussed. In a review of the literature on distraction and aging, Layton (1975) suggested that older adults are more distractible than younger adults because they are unable to suppress perceptual noise, that is, they cannot avoid processing irrelevant stimuli. In a stringent test of this hypothesis, Wright and Elias (1979) tested younger and older adults on Eriksen and Eriksen's (1974) flanker paradigm. The flanker task, a visual choice-reactiontime task, presents participants with a display consisting of (at least) three letters, side by side. Participants are asked to categorize the central target letter and to press a key to indicate in which of two artificially defined categories it is a member. The nontarget letters are members of the same response category, members of the other response category, or neutral letters from neither category. In this task, the target location is known in advance; therefore, there is no reason to process the distractor items consciously. However, both of these sets of researchers demonstrated that the nontarget letters are processed nonetheless. From Laytonls hypothesis, Wright and Elias predicted that the older adults would show a greater effect of the distractor, or