Age differences in the selection of mental sets: the role of inhibition, stimulus ambiguity, and response-set overlap.
Switching between tasks leads to response-time (RT) costs at switch points (local switch costs) and often to RT costs at no-switch transitions that occur in the context of a task-switching block (global set-selection costs). With trial-to-trial cuing of tasks, moderate age effects were obtained for local switch costs, but large age effects were obtained for global selection costs. In Experiment 1, set-specific inhibition was found to be at least as large in old as in young adults, thus ruling out an inhibition deficit as a reason for age differences in global costs. In Experiment 2, large age differences in global costs were limited to conditions of ambiguous stimuli and full response-set overlap. This pattern of results suggests a greater reliance on set-updating processes in old than in young adults. The role of these processes is to ensure unambiguos internal control settings when ambiguity arises from stimuli and response specifications.
Mayr
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Department of Psychology, University of Oregon, Eugene 97403, USA. mayr@oregon.uoregon.edu
D000328:Adult; D000367:Age Factors; D000368:Aged; D000375:Aging; D003071:Cognition / Q000502:physiology*; D005260:Female; D006801:Humans; D007266:Inhibition, Psychological; D008297:Male; D009042:Motivation; D011597:Psychomotor Performance; D011930:Reaction Time