For the past 20 years, my research interests have centered on the neuroscience of learning and memory.   In the last decade, I have concentrated on understanding the mechanisms of extinction (reduction) of fear in mice, a form of learning particularly relevant to psychiatric treatments.  

Extinction is a procedure in which repeated exposure to something one fears reduces fear of it (as long as nothing bad happens!) Lots of experiments show that extinction does not erase fearful memories. Instead it suppresses their expression by countering them with new memories of safety. Extinction of fear in animals has been a model for the treatment of anxiety in humans for almost a century, and previous studies of extinction have guided the design of successful psychotherapy for most anxiety disorders.  

My most recent research has identified medications that appear to accelerate the process of extinction. These medications do not reduce fear directly. However, in mice, extinction of fear in the presence of these drugs is faster and sometimes more lasting than extinction in their absence. Most recently, I have been attempting to develop and collaborate in clinical trials to see whether these medications will work to facilitate treatment of human anxiety disorders, particularly of post-traumatic stress disorder (PTSD).