Contributions of Cognitive Aging Models to the Explanation of Source Memory Decline across the Adult Lifespan.
Level 4 - case-series / case-control
Cross-sectional observational study evaluating cognitive models via structural equation modeling (CEBM non-clinical analogy Level 4).
PubMed 32208813 · doi:10.1080/0361073X.2020.1743920
What was done
Structural equation modeling was applied to cross-sectional data from 1,554 healthy adults aged 21 to 80 years (analyzed overall and stratified into young, middle-aged, and older adult cohorts) to evaluate four cognitive aging frameworks explaining source memory decline: processing resources (working memory discrimination), speed of processing (working memory reaction times), cognitive reserve (education), and knowledge (vocabulary).
What was found
Processing resources mediated the relationship between age and source memory performance across the entire adult lifespan. Other models demonstrated stage-specific mediation: speed of processing mediated age effects only in young adults, cognitive reserve only in middle-aged adults, and knowledge only in older adults. The abstract reports no numerical values, effect sizes, or model fit indices.
Why it matters
By comparing four prominent cognitive aging frameworks within a single large cohort, the study suggests that processing resource capacity is the primary continuous contributor to source memory decay, while other mechanisms operate during specific adult life stages.
Limits
The study is cross-sectional, precluding causal inference or measurement of true within-person cognitive trajectories over time. Each cognitive model was operationalized with a single proxy measure (e.g., education for cognitive reserve), and no numerical point estimates or confidence intervals were provided in the abstract.
Cited by
- supports Source memory tends to decline with age.