Why does neuronal damage in neurodegenerative diseases often spread beyond the initially affected area of the brain?

💡 Explanation

Neuronal damage spreads due to prion-like propagation of misfolded protein aggregates such as amyloid, tau, or alpha-synuclein. These aggregates act as seeds, inducing misfolding in healthy proteins, therefore expanding the pathology to connected regions, rather than merely affecting metabolically active areas.

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