ACVRL1 and Cognitive impairment: ALK1 signal in the parenchymal CA1 arteriolar walls decreased significantly in ADpatients regardless of the presence of CAA in comparison with subjects with early ADneurofibrillary tangles accumulation (BB III) that were either cognitively intact (CDR0)or had mild cognitive impairment (CDR0.5) (Figs3A–D and 4A,B).