NRGN and Alzheimer disease: Plasma dilution experiments using AD‐like Subtype 6 CSF demonstrated that introducing plasma into neuronal hyperplastic AD subtypes54 with high tau and synaptic protein biomarkers (e.g., NRGN, GAP43, BASP1) mirrors the proteomic network module shifts toward Subtype 3, leading to reductions in neuronal proteins, including tau, while increasing plasma‐associated proteins.