My research work is focused primarily on the use of magnetic resonance imaging to investigate cerebral physiology and brain activation by psychostimulants. I am the Principal Investigator of a project with the specific aim to use functional magnetic resonance imaging technology to investigate development of acute tolerance to the cerebral stimulating effects of cocaine that occurs with prolonged drug exposure. A new awake behaving model permits longitudinal studies of long-term drug exposure without the confounding effect of anesthesia. Our efforts are focused on elucidating the neuroadaptations associated with long as well as short-term exposure to cocaine and nitrous oxide, an inhaled gas producing both analgesia and anesthesia, on brain activation. We have investigated the cerebral stimulating effects of inhaling nitrous oxide and, similar to cocaine, the ability to induce release of dopamine in the brain reward circuitry.

In parallel with this effort is a collaboration with Dr. Joseph B. Mandeville of the Mass General NMR center to investigate the relationship between cerebral blood flow, blood volume, and oxygen consumption during neural activation. The goal of this work is to better understand the mechanism by which the brain couples cerebral vascular hemodynamics to metabolism; a concept fundamental to the basis of almost all techniques to image functional activity of the central nervous system. My interest is to investigate how this process of coupling of cerebral vascular responses is altered by pathological states including cocaine exposure, as well as angiogenesis and acute ischemia.