Stem cell research in my lab is focused on the mechanisms regulating stress responses in compromised tissue beds, and how stem cells can be used to lessen the severity of radiation- and chemotherapy-induced normal tissue injury in the brain. Current research has evolved from a formal training in radiation biology and from past studies investigating radiation-induced genomic instability and redox stress biology. Significant effort is focused on elucidating the molecular and biochemical mechanisms regulating the response of stem cells within the irradiated microenvironment. Current research seeks to define the mechanisms underlying the beneficial effects of stem cell transplants on radiation-induced cognitive dysfunction. This work has also expanded to define the mechanisms underlying chemotherapy-induced cognitive decrements, a condition commonly referred to as “chemobrain.” Significant research is focused on determining how transplanted stem cells improve cognition after irradiation and chemotherapy, efforts designed to ameliorate the adverse cognitive side effects suffered in millions of cancer survivors subjected to various irradiation and chemotherapeutic regimes. Correspondingly, significant work in my lab is now focused on stem cell strategies as potentially useful and novel clinical interventions for improving long-term cognitive health following cytotoxic cancer treatments. Long-standing interests continue to explore the adverse effects of exposure to the space radiation environment, where in vitro and in vivo models are used to define biological responses to charged particle irradiation. These efforts have defined the importance of radiation-induced oxidative stress as a biochemical mechanism regulating the functionality of neural stem cells. Much of this work is also applied to the field of low dose radiobiology, where the impact of environmentally relevant exposures to the CNS of sparsely ionizing radiation are evaluated. Projects focused on understanding radiation effects of charged particles in space or low dose terrestrial exposures are aimed at defining specific risks to human health, such as carcinogenesis, neurodegeneration, and cognitive performance.