The Role of Neuroglia in Cognitive Longevity

The concept of the central nervous system (CNS) reserve emerged from the mismatch often observed between the extent of brain pathology and its clinical manifestations. The cognitive reserve reflects an "active" capacity, driven by the plasticity of CNS cellular components and shaped by experience, learning, and memory processes that increase resilience. We propose that neuroglial cells are central to defining this resilience and cognitive reserve. These cells maintain CNS homeostasis through allostatic mechanisms and modulate responses to injury and/or disease. In this review, we first outline the concept of the CNS reserve and then explore the role of neuroglia in maintaining brain function throughout development and adulthood. We highlight astrocytes and oligodendrocytes in gray and white matter learning, respectively, and examine the function of microglia in immune surveillance. We conclude that neuroglia are key contributors to the cognitive reserve, with systems such as the noradrenergic pathway supporting tissue under stress and mitigating pathology through compensatory responses.