How can the aging brain form new synapses despite the loss of neurons?

The aging brain maintains its functionality despite the natural loss of neurons through a process known as neuroplasticity. Even as some neurons atrophy or die, the brain compensates by forming new synapses—the connections between neurons—and by developing new branches of nerve fibers from viable, remaining neurons.12

This capacity for reorganization allows the nervous system to adapt and maintain adequate function throughout the human lifespan, including into extreme old age. These mechanisms of synaptic adjustment are fundamental to the brain's ability to reorganize its networks in response to changes, damage, or the ongoing demands of processing information. While neuronal loss is a characteristic of aging, it does not necessarily result in a comparable loss of function, as these compensatory structural changes help preserve cognitive and behavioral stability.134