Abstract of the proposed supplement highlighting the relevance to AD/ADRD Financial loss due to reduced decision-making capacity and increased risk of deception constitutes a burgeoning public health crisis. A digitally connected world has shifted financial fraud into the online realm. Healthy older adults and those with dementia (e.g., Alzheimer’s disease) may be at particular risk for financial exploitation in an online context, as they must navigate the complexities and ambiguity of internet decision making while also dealing with cognitive, socioemotional, and neurobiological changes associated with age and the disease. These individuals at heightened exploitation risk, however, are neglected in research on cyberattacks. One strategy for closing this knowledge gap, in alignment with the parent grant’s goal of determining financial deception risk profiling, is to uncover the impact of higher risk for accelerated cognitive decline and Alzheimer’s disease on online decision making. From this perspective, under the umbrella of the parent grant, the goal of the supplement is to determine in the parent grant cohort apolipoprotein E4 (APOE4) allele status, which increases risk for Alzheimer’s disease. The supplement will further extend risk surveillance and profiling into the MindCrowd project, which comprises a larger adult lifespan sample previously genotyped for APOE4 status, cognitively phenotyped, and for whom first-degree family history of Alzheimer’s disease is known. The supplement will (i) determine whether APOE4 carriers are at increased susceptibility to financial exploitation in aging (AIM 1); (ii) investigate APOE4 impact on the link between cognitive/socioemotional functions and financial exploitation risk in aging (AIM 2); and (iii) determine the role of APOE4 status on associations between brain structure, brain function, and financial exploitation risk in aging (AIM 3). These novel AD/ADRD supplement aims are embedded in our Cognitive/Socioemotional Neuroscience Model of Financial Decision-Making and Deception Risk in Aging and build on preliminary data from the parent grant supporting high susceptibility to online deception among older adults in our ecologically valid, behavior-based field experiment (PHishing Internet Task; PHIT) and particular risk susceptibility among APOE4 allele carriers in our newly developed Phishing Email Suspicion Test (PEST); especially among APOE4 carriers with low cognitive function. This supplement will leverage the established infrastructure of the parent grant to genotype the parent grant cohort of N=280 young, middle-aged, and older adults on APOE4 status (Study 1); and uniquely broaden data collection by administering our two new online fraud susceptibility paradigms (PHIT, PEST) as well as a short socioemotional/financial decision making battery in the MindCrowd cohort (N=1,000; 20-95 years; Study 2). Results from this supplement will allow extension of our integrated, conceptually driven approach...