MAPT and Brain atrophy: Previous studies have shown tau biomarkers (on PET and in CSF) or a ratio of Aβ/tau to be more closely related to cognition than Aβ alone.26, 27 Vemuri and colleagues also illustrated that CSF biomarkers and cognition were not correlated, supporting the use of alternate imaging markers such as MRI of brain atrophy.19 Our results illustrate a strong association between Aβ and cognition, suggesting that amyloid accumulation may play a significant role in cognitive decline.