Age-related differences in arithmetic problem-verification strategies.

To test age-related differences in split and problem-difficulty effects, adults between the ages of 20 and 80 years (N = 138) performed a simple and a complex inequality verification task (e.g., 6 + 3 < 11, 271 + 182 < 458; true or false?). Split effects in verification tasks (i.e., better performance for large-split than for small-split problems) reflect strategy selection between nonexhaustive verification (e.g., evaluation of plausibility; estimation) and exhaustive verification (e.g., retrieval; calculation). Problem-difficulty effects (i.e., better performance for easy than hard problems) reflect calculation processing. Results showed decreased split effects across age groups, particularly in the complex task. Moreover, problem-difficulty effects did not vary across age groups. Age-related changes were mostly mediated by age-related declines in processing speed.