A new study published in Psychology and Aging examined the links between personality, psychological characteristics, and cognitive outcomes in older adults, finding that higher levels of positive affect and Openness are associated with reduced cognitive decline, even when accounting for brain atrophy.
Cognitive decline in older age has profound implications for one’s dependence and need for care. Prior studies have linked personality traits to cognitive outcomes, suggesting personality may influence one’s risk of cognitive decline. Most of these studies have focused on Big Five personality in often homogenous populations without considering brain integrity as a potential moderating factor. In this work, Sarah Tomaszewski Farias and colleagues expanded on this limitation.
This study recruited 157 English- or Spanish-speaking older adults over age 60 from the University of California Davis Alzheimer’s Disease Research Center’s Longitudinal Diversity Cohort. Exclusion criteria included unstable major medical illness or serious psychiatric disorder. This sample received annual clinical evaluations, including detailed medical history, physical and neurological exams, as well as diagnoses of cognitive syndromes.
Participants completed various questionnaires between January 2018 and February 2020 assessing the Big 5 traits (i.e., Openness, Conscientiousness, Agreeableness, Neuroticism, Extraversion) and traits such as positive and negative affect, sense of purpose, loneliness, grit, and self-efficacy.
Cognitive outcomes were measured with the Spanish and English Neuropsychological Assessment Scales, which assesses cognitive domains like episodic and semantic memory, executive function, and spatial ability. Baseline brain MRI scans also provided measures of gray matter, hippocampal volume, and total white matter hyperintensity volume, allowing the researchers to assess for brain atrophy.
Tomaszewski Farias and colleagues observed associations between various psychological traits and cognitive outcomes. Higher levels of positive affect and Openness were linked to less cognitive decline over time, even after controlling for baseline brain atrophy measures, suggesting these traits have a direct influence on cognitive trajectories.
On the other hand, higher levels of sadness were associated with more cognitive decline, but this relationship was not significant after adjusting for brain atrophy, suggesting that the impact of sadness on cognitive outcomes may partly be mediated by brain health. Traits such as grit, self-efficacy, and purpose in life revealed weaker and less consistent associations with cognitive outcomes.
Cross-sectional analyses involve looking at data at a single point in time to identify relationships between variables. In this snapshot, sadness was a consistent predictor of poorer cognitive performance across episodic memory and spatial ability. Positive affect and Openness, while strongly associated with longitudinal cognitive trajectories, showed less consistent cross-sectional relationships with specific cognitive domains.
A limitation to this research is the relatively small sample size which may limit the generalizability of findings.
Overall, this study highlights the important role of psychological well-being in mitigating cognitive decline in older adulthood.
The study, “Associations between personality and psychological characteristics and cognitive outcomes among older adults”, was authored by Sarah Tomaszewski Farias, Fransia S. De Leon, Brandon E. Gavett, Evan Fletcher, Oanh L. Meyer, Rachel A. Whitmer, Charles DeCarli, and Dan Mungas.