Older yet faster: Representational development explains accelerated semantic processing in older adults.

Slower responses in older age are often taken as evidence for cognitive decline, yet they may also stem from representational changes shaped by lifelong learning. Building on the information-accumulation perspective on aging, we argue that behavioral change across the lifespan can arise from representational systems continuously updated through learning from the environment. This view predicts that aging may bring both benefits and costs: Performance improves when task demands are congruent with accumulated knowledge but declines when they conflict. We provide convergent evidence for this account across three studies, each comprising the following components. First, in tasks requiring participants to access word meanings (i.e., when task demands were congruent with representation), we found that older adults (70–80 years old) exhibited faster semantic processing speed than younger adults (18–25 years old), a finding that cannot be explained by decline-based accounts. Second, we traced this processing advantage to systematic changes in older adults’ conceptual representations inferred from semantic rating tasks. Third, using learning simulation models, we demonstrated how such representational changes could emerge naturally from cumulative language experience. Replications across different samples, task requirements, and word stimuli strengthen the robustness of these findings. Finally, we identified a boundary condition: When learned representations contain information incongruent with task demands, older adults’ greater learning experience not only attenuates their representational changes but also reduces processing-speed advantage. Altogether, our research challenges the explanatory framework of cognitive aging that emphasizes decline and compensation, advancing a more balanced view grounded in representational development and lifelong learning.