An athlete sustains a concussion; imaging shows no visible macroscopic damage. Which mechanism explains ongoing cognitive deficits despite the absence of large-scale lesions?

💡 Explanation

Diffuse axonal injury, a primary effect of concussion, occurs because rapid head acceleration generates shear strain that deforms and damages axons at a microscopic level. Therefore, cognitive deficits persist despite lack of visible lesions, rather than edema-induced hypoxia, contusions, or meningeal irritation.

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