Several studies have shown the promise of cognitive ERP (event-related potential) as a cost-effective and non-invasive modality for monitoring forms of pathological aging such as Alzheimer’s Disease. Specifically, ERP waveforms P600 and N400 have been shown to be sensitive to pathological aging and potentially predictive for development of Alzheimer’s Disease. In collaboration with UCSD, the Olichney Cognitive Electrophysiology and Neuroimaging (CEAN) lab has been conducting a multiyear longitudinal study to better understand and characterize Alzheimer’s Disease progression through ERP biomarker analysis. This study involves recruitment of four patient groups (control, “preclinical” Alzheimer’s Disease, mild cognitive impairment, and mild Alzheimer’s Dementia) that undergo initial ERP testing with repeat testing at 12 months and 24 months. Here, we assess the preliminary changes seen in ERP waveforms P600 and N400 for enrolled patients with AD progression at baseline when compared to a normal aging cohort. By using average z-scores for each patient group, we found that P600 amplitude was reduced significantly in all three AD groups when compared to the normal control. This suggests that P600 may be a sensitive marker of AD progression prior to clinical symptoms showing. We also found that the N400 congruous effect was increased in MCI and AD patients but not preclinical AD, suggesting that N400 changes may occur later in AD progression than P600. Due to small sample size, however, further statistical analysis must be conducted to confirm these trends when enrollment restarts in Spring 2021.