Mass General Research Institute
Associate Professor of Psychiatry
Harvard Medical School
cocaine-related disorders; dreams; extinction, psychological; fear; memory; sleep; sleep, rem; substance withdrawal syndrome; wakefulness
In the Sleep and Anxiety Disorders Laboratory, we use polysomnography, fMRI, psychophysiology, self-report and related techniques to investigate how sleep helps humans regulate their emotions. Specifically, we study the influence of sleep disturbance on the development of anxiety and traumatic-stress related disorders. Preexisting sleep disturbance increases the odds of incident anxiety disorders and of PTSD following a traumatic stressor. Sleep plays an important role in the consolidation of emotional memory. I am particularly interested in how sleep influences evolutionarily ancient learning and memory processes that contribute to human emotion regulation and are deficient in anxiety disorders and PTSD. Such processes include fear extinction--learning that a once feared object or event is no longer dangerous--and habituation whereby we become less reactive to frequently encountered stimuli. My research strives to identify the effects of sleep on these elemental forms of emotional memory at the levels of behavior, physiology and neural circuits. Extinction and habituation are key components of a first-line treatment for anxiety disorders and PTSD, exposure therapy, a process whereby therapeutically introduced extinction and habituation memories aid in overcoming debilitating fears. We examine sleep and brain activity using experimental models of extinction and habituation. Additionally, we examine sleep effects in clinical applications of extinction learning such those that occur during exposure therapy for anxiety disorders.