The brain regions predominantly affected by AD exhibited NMDARs primarily composed of GRIN2A (GluN2A) and GRIN2B (GluN2B), while extrasynaptic NMDARs, containing GRIN2B subunits, have been linked to neuronal excitotoxicity (Hardingham and Bading 2010). Here, GRIN2B is linked to Alzheimer disease.