The role of inhibitory control in age-related operation span performance.

The present study was conducted to examine the inhibitory deficit theory on cognitive performance in old age. An experimental manipulation was applied to investigate if the efficiency of inhibitory control directly affects age-related working memory performance as measured by the operation span task. Forty-two older (M = 67 years, SD = 5.12) and 42 younger adults (M = 25 years, SD = 4.06) performed two versions of the operation span task that differed in the inhibitory demands placed on working memory. Age effects were confirmed for both versions of the operation span task. Importantly, the age effect was qualified by an age × inhibitory demands interaction indicating that age differences in the high inhibitory-demands condition were even larger than in the standard condition. In conclusion, this supports the assumption that inhibitory deficits contribute to age-related working memory performance.