Radiation and the Brain: An Overview of Neurological Implications of Exposure

After the industrial and technological revolutions, radiation exposure became unavoidable, emitted from natural cosmic and terrestrial sources, medical procedures, and the electromagnetic technologies. Although radiation-induced brain injury is well documented, the molecular mechanisms of injury are still being investigated. Furthermore, accumulating evidence suggests damaging effects of non-ionizing radiation on brain homeostasis with significant clinical outcomes. This review investigates and synthesizes current knowledge from clinical, experimental, and epidemiological studies on the mechanisms, outcomes, and clinical relevance of radiation-induced brain injuries. Ionizing radiation disrupts neural integrity through DNA damage, neurovascular disintegration, neuroinflammatory cascades, and neuronal injury. These mechanisms manifest clinically in acute, subacute, and chronic phases, ranging from transient cognitive impairment and fatigue to progressive neurodegeneration, cerebrovascular injury, cranial neuropathies, and rare but severe complications such as carotid blowout syndrome or malignant tumors. Non-ionizing radiation has been associated with neurocognitive impairments and an increased tumor risk, though findings still lack scientific consensus. Given the ubiquity of radiation exposure and the nonspecific nature of the clinical symptoms, they are frequently underrecognized in clinical practice. Improved diagnostic awareness, a thorough exposure history, and early identification may mitigate progression and disability. Preventive strategies include precision radiotherapy techniques, pharmacological neuroprotection, behavioral interventions, and updated public health guidelines for electromagnetic exposure. Radiation-induced brain injury represents an underestimated clinical and public health concern that urges systematic reassessment, interdisciplinary collaboration, and evidence-based preventive strategies.