Cognitive Reserve Buffers the Impact of Traumatic Events and Post-Traumatic Stress Symptoms on Mid- to Late-Life Cognitive Performance

Objective: Exposure to potentially traumatic events is common across the lifespan, yet individual differences in cognitive outcomes following trauma exposure in older adults remain poorly understood. Cognitive reserve (CR) may protect against trauma-related cognitive deficits, but CR's moderating role in relationships between trauma exposure, post-traumatic stress symptoms, and cognition is unclear. Methods: We examined 745 community-dwelling middle aged to older adults (50-86 years) who completed assessments of traumatic event exposure (Life Events Checklist for DSM-5), post-traumatic stress symptoms (PCL-5), cognitive performance, and CR proxies (Cognitive Reserve Index Questionnaire and verbal intelligence). Results: Higher CR scores protected against cognitive performance deficits correlated with both greater exposure to traumatic events and post-traumatic stress symptoms, and were associated with reduced post-traumatic stress symptoms associated with greater traumatic event exposure. Moderated mediation analysis revealed that for individuals with lower CR, the negative cognitive effects associated with traumatic events were mediated through post-traumatic stress symptoms, while this indirect effect became non-significant at higher CR levels. CR proxies showed different protective effects by trauma type, with higher CR buffering against poorer cognitive performance associated with natural/accidental traumas. Discussion: These findings suggest that interventions targeting modifiable CR components may build resilience against trauma's psychological and cognitive impacts throughout the lifespan.