Factors influencing rates of unsupervised assessment of short-term learning in cognitively unimpaired adults.

Background: In older adults with preclinical Alzheimer's disease (AD), learning curves derived from validated psychological learning paradigms are reduced to an extent greater than impairment, or decline, on neuropsychological memory tests. Objective: This study aimed to examine how age, sex, education, mood, and general dementia risk, which also increases risk for preclinical AD, could influence learning curves. Methods: 1050 adults enrolled in the BetterBrains trial completed 10 blocks of ORCA-LLT learning trials over 5 days. Learning curves were derived from improvement in accuracy over trials. Participants also completed questionnaires of demography and mood, and the CAIDE risk score was computed for each participant. Results: Most participants (67%) completed ≥6 blocks of ORCA-LLT. Older age (d = 0.75), lower education (d = 0.50), and higher dementia risk (d = 0.36) were associated significantly with slower learning rates. Conclusions: In older adults, learning curves are influenced subtly by age, education, and dementia risk but not by sex or mood. [ABSTRACT FROM AUTHOR]