Cognitive reserve refers to an individual's capacity to maintain cognitive function in the face of age-related or disease-related structural brain changes. Higher education, complex occupational experience, rich social interaction, and sustained intellectual activity accumulate reserve. Through enhanced neural network efficiency and recruitment of alternative pathways, individuals with high reserve show slower cognitive test score decline despite equivalent levels of brain atrophy.
Theoretical Framework of Cognitive Reserve
Models of reserve can be divided into a passive type and an active type, and cognitive reserve corresponds to the active model. The passive model (brain reserve) posits that anatomical surplus such as synaptic density and brain volume serves as a buffer until a critical threshold is reached. The active model describes the ability to use existing neural networks more efficiently (neural efficiency) and to recruit alternative circuits when primary pathways are damaged (neural compensation).
Factors That Build Reserve
The primary contributors to cognitive reserve accumulation are years of education, occupational cognitive complexity, intellectual leisure activities, and social network richness. One account also lists bilingualism as a contributor to reserve.
Cognitive Testing and Reserve
Cognitive reserve is proposed to explain why some people maintain cognitive function despite brain changes comparable to those of others.