The effect of increasing the number of stimuli to be recalled was investigated to evaluate whether sensitivity for memory impairment was enhanced in adults with Down syndrome when using higher task load. Three levels of load were compared across three groups of adults: those with cognitive deterioration, no cognitive deterioration over age 40, and no cognitive-deterioration under 40. The cognitive-deterioration group showed impaired performance in comparison to the no cognitive-deterioration--40+ group at all levels of task load, with performance declining over 4 years. The no cognitive-deterioration--40+ group showed no impairment in performance compared to no cognitive-deterioration--under 40 group, except when task load was high. Implications for identification of dementia and age-related cognitive change are discussed.