We are focused on understanding neurovascular mechanisms by which cognitive decline occurs in healthy aging that is accelerated during chronic hypertension and cerebrovascular disease. Specifically, we investigate the novel role of the small arterioles perfusing the ischemic-prone hippocampus in healthy cognitive aging and vascular cognitive impairment and dementia using rodent models. We determine hemodynamic and cognitive consequences of age- and hypertension-induced hippocampal vascular dysfunction, including changes in basal blood flow, neurovascular coupling, neuroplasticity, learning and memory. We are interested in understanding sex differences in hippocampal vascular dysfunction, particularly in the post-menopausal state that may increase the susceptibility of the hippocampus and its vasculature to damage and promote vascular dementia. Combined in vivo and ex vivo methodologies include: studying the function of isolated and pressurized hippocampal arterioles via pressure myography, measuring absolute hippocampal perfusion using hydrogen clearance, assessing neurovascular coupling by measuring simultaneous changes in hippocampal blood flow during a spatial navigation task, determining neuroplasticity using hippocampal slice electrophysiology, and investigating the trajectory of cognitive decline using behavioral tests of learning and memory. The overall goal is to understand the function of hippocampal arterioles and hippocampal hemodynamics in order to develop strategies to protect the hippocampus from hypoxic/ischemic injury during aging and disease states associated with vascular dementia to slow cognitive decline and maintain neurocognitive health.