Inclusion Criteria:  Cognitive impairment/decline, memory impairment/loss, or Alzheimer's disease or dementia and bariatric surgery • Cognitive impairment/decline, memory impairment/loss, or Alzheimer's disease or dementia and obesity, and no bariatric surgery history  Exclusion Criteria:  Patients without a history of memory impairment/loss, bariatric surgery, or obesity  Patients outside of University of California Davis Health System Patients unable to provide consent