P2‐430: RELATIONSHIPS BETWEEN LONGITUDINAL RATES OF LEARNING AND MEMORY DECLINE AND DIFFERENT FORMS OF CEREBROVASCULAR PATHOLOGY IN COGNITIVELY UNIMPAIRED BRAIN DONORS. (1st July 2019) - Malek-Ahmadi, Michael; Belden, Christine; Powell, Jessica; Zamrini, Edward; Adler, Charles; Sabbagh, Marwan N.; Shill, Holly; Jacobson, Sandra; Caselli, Richard J.; Woodruff, Bryan K.; Rapscak, Steven Z.; Ahern, Geoffrey L.; et al.