Transcranial magnetic stimulation from healthy brain aging to Alzheimer's disease: a review on mechanisms, therapeutic potential, and future clinical directions.

Transcranial magnetic stimulation (TMS), a non-invasive and non-pharmacological intervention, is increasingly being explored for mitigating age-related cognitive decline and dementia. Its therapeutic potential is largely attributed to its capacity to modulate neuronal firing rates and induce neuroplastic changes and modulate neurovascular coupling within distributed neural networks that support memory, attention, and executive function. Despite growing interest, gaps remain in understanding how specific stimulation parameters engage in neural circuits and translate into meaningful cognitive outcomes in aging and neurodegeneration. This narrative review synthesizes current evidence on the neurophysiological and hemodynamic mechanisms and clinical effects of repetitive TMS (rTMS) across the spectrum of cognitive aging, from healthy older adults to those experiencing age-related cognitive decline and Alzheimer's disease. By integrating mechanistic and clinical perspectives, this review bridges basic neuroscience and clinical practice, highlighting rTMS's emerging role in promoting cognitive resilience and healthier brain aging.