Abstract of the proposed research that shows the relevance to AD/ADRD Chronic pain and Alzheimer's disease and related dementias (AD/ADRD) are common in older age and emerging evidence links pain as a significant risk factor for subsequent cognitive decline and dementia. However, the up-to-10-year preclinical phase of AD/ADRD with no objective cognitive deficits significantly limits the study of pain’s potential impact on cognition, and once diagnosed, there are significant limitations assessing the multidimensional pain experience using verbal reports. Given the complexity of chronic pain in aging, there are likely a combination of mechanisms contributing to pain-cognitive decline interactions. Our own previous work has demonstrated accelerated biological aging in persons with chronic pain including accelerated brain aging using brain aging biomarkers known to predict cognitive decline and AD. Thus, the current study aims to determine the association between brain tissue and blood-derived epigenetic aging biomarkers along with determination of brain aging from the clinical MRIs within the same individual to further understand biological aging interactions and potential underlying neurobiological mechanisms. The proposed research addresses a significant gap in the literature and would be the first to evaluate pain-related differences in multi-tissue-derived epigenetic aging and associations with brain aging biomarkers derived from clinical MRIs.