A - 97 Performance Variability in a Multitrial List-Learning Task in Differentiating between Fronto-Temporal Dementia, Alzheimer’s Disease, and Normal Healthy Controls

Abstract Objective Alzheimer’s Disease (ad) and Frontotemporal Dementia (FTD) are neurodegenerative diseases with differing cognitive profiles. This study explored word-list learning task performance differences between ad and FTD and from healthy older adults (NHC). Method This study utilized results of the CERAD-NAB Word List task, stored in a database by the OHSU Layton Aging and Alzheimer’s Disease Center. Outpatient subjects (n = 2099), ages 56+ (M = 83.61; SD = 11.44), tested from 1989 to 2020, were included, diagnosed as “NHC,” “ad,” or “FTD.” Participants included 88.8% Caucasian, 9.8% Black, 1% Asian, and 0.3% Native. Inclusion criteria involve the CERAD-NAB Word List task and a diagnosis of “NHC”, “ad”, or “FTD” at their last visit. Exclusion criteria apply to participants without diagnoses including ‘NHC, “ad”, or “FTD”. A factorial analysis of variance was conducted to compare raw scores of each group’s performances on Trials 1, 2, 3, delayed, and recognition retention. Results There was a significant impaired learning variability in each trial with poor encoding in adults with ad when compared to FTD. In Trial 3, the difference in performance between the FTD group and the ad group was statistically different, suggesting better recall in the FTD group. Conclusions Findings suggest a similar pattern of encoding difficulties with individuals diagnosed with ad and FTD. The FTD groups were able to better recall the list following a delay as compared to the ad group. Combined investigation of cognitive and neurobehavioral symptoms coupled with clear patterns in verbal memory deficits could provide a more accurate approach for differentiating between ad and FTD.