This study used **data** from the Wisconsin Registry for Alzheimer's Prevention (WRAP) cohort (Table 1), a longitudinal registry of > 1500 cognitively healthy adults recruited in middleage and enriched for AD risk factors of APOE e4 carriage and parental family history of AD (Sager et al., 2005). Determination of APOE e4 and FH status in this sample has been previously described (Jonaitis et al., 2013;Koscik et al., 2014).