Cognitive Reserve, Resting EEG and Cognition

Cognitive reserve (CR) is the ability to adapt cognitive function to resist the onslaught of brain-related injury or the normal aging process. The underlying brain mechanisms of CR through electroencephalogram (EEG) are scarcely reported; moreover, none of them consider dynamic proxy measures of CR. We explored the association of CR with cognition and resting-state EEG in older adults using three of the most representative dynamic proxy measures of CR: intellectual ability, leisure activities, and physical activities. Eighty-eight healthy older adults aged 60-77 (58 female) were selected from previous study data. A hierarchical cluster analysis considering scores on intellectual ability, leisure activities, and physical activities classified the participants into three groups of CR: Leisure-Active (n = 31), Active-Creative (n=27) and Passive-Receptive (n=30). Differences in cognitive performance and the absolute power (AP) on six resting-state EEG factors (beta, alpha1, alpha2, gamma, theta, and delta) were examined between the CR groups. Active-Creative and Leisure-Active groups reported a higher performance on processing speed compared to the Passive-Receptive group. The Active-Creative group reported a higher performance on phonological fluency than the other two groups and showed higher performance on motor programming than the Leisure-Active group. The Leisure-Active group displayed higher AP in alpha1 than the Passive-Receptive group and higher alpha2 than the Active-Creative group. The dynamic proxy variables of CR are differently associated with cognitive performance and resting-state EEG. Implementing leisure and physical activities may promote better cognitive performance through compensation or neural efficiency mechanisms.