Network signatures of age-related cognitive decline

Amyloid pathology and cerebrovascular disease are the most frequent, and best characterized, mechanisms linked to age-related cognitive decline and dementia. The relationship between these mechanisms and phenotypes of normal aging, mild cognitive impairment, and dementia has recently been explored in vivo with neuroimaging markers of small vessel disease (SVD) and amyloid deposition (respectively, white matter hyperintensities [WMH] identified on T2-weighted or fluid-attenuated inversion recovery [FLAIR] MRI, and binding of the β-amyloid selective radiotracer Pittsburgh compound B [PiB] on PET). These techniques have accelerated understanding of disease burdens in preclinical and clinical states of impaired cognition.