Personality and memory: accelerometer-measured physical activity as a potential explanatory pathway

OBJECTIVES: Self-reported physical activity (PA) mediates the association between personality and cognition. This study examines whether accelerometer-based measures of physical activity and sedentary behavior mediate the association between personality and memory. METHODS: Participants were 2471 individuals aged 50 to 89 years (mean age = 69.70, SD = 8.56) from the English Longitudinal Study of Ageing. Personality traits, sociodemographic factors, accelerometer-measured PA, and memory were assessed in Wave 10 (2021/2022). RESULTS: Higher neuroticism was associated with lower memory performance, whereas extraversion, openness, and conscientiousness were related to better memory. The associations of extraversion and conscientiousness with memory were partially mediated by their associations with higher daily step count (19% and 7% proportion mediated), overall PA (25% and 12%), light PA (LPA, 23% and 14%), moderate-to-vigorous PA (MVPA, 10% and 3%), and lower sedentary behavior (17% and 8%). To a lesser extent, lower step count (4%) and higher LPA (6%) mediated the associations between neuroticism and lower memory and between openness and higher memory, respectively. CONCLUSION: Using objective accelerometer-based measures of daily movement, the present study provides novel evidence for PA as a potential explanatory mechanism between personality and memory.