P2‐603: MEAN ARTERIAL BLOOD PRESSURE (MABP) IS ASSOCIATED WITH SPATIAL WORKING MEMORY PERFORMANCE VIA AN EFFECT UPON FORNIX MICROSTRUCTURE IN OLDER ADULTS WITH AGE‐ASSOCIATED MEMORY IMPAIRMENT (AAMI). (1st July 2019) - Reddan, Jeffery Michael; White, David; Kurani, Ajay S.; Pipingas, Andrew; Macpherson, Helen; Rowsell, Renee; Parrish, Todd; Scholey, Andrew