Group Leaders: Dr. Victoria Risbrough, Ph.D. and Dr. Tanja Jovanovic, Ph.D.

PTSD is a complex disorder, and there is a need for development of rapid, quantifiable and objective measures associated with this diagnosis and symptom severity to improve both basic mechanisms studies of PTSD as well as development of markers of treatment response. The PGC PTSD psychophysiology group aims to understand the heritability and shared genetic risk between psychophysiological phenotypes associated with PTSD and PTSD diagnosis. Our group focuses on psychophysiological phenotypes including cardiovascular measures, acoustic startle reflex, affective modulation of startle, conditioned fear and extinction, as well as skin conductance response. Across 3 sites we have amassed ~2000 subjects with acoustic startle and cardiovascular variables and aim to expand this collection. We will characterize genes and pathways associated with these intermediate phenotypes and examine if genetic risk profiles of these traits predict genetic risk for PTSD. Importantly, these phenotypes are cross-species markers of enduring stress response and thus gene hits can be rapidly “back-translated” to animal models using these phenotypes for validation and assessment of mechanism. Conversely, genes implicated in animal studies using these homologues measures will be validated in our human samples.

Dr. Victoria Risbrough, Ph.D.

Dr. Risbrough’s research is centered on translational mechanisms and treatments of anxiety disorders using preclinical and clinical approaches. Her primary focus is understanding mechanisms of risk and resilience to anxiety disorders, particularly post-traumatic stress disorder. For example, she examines the contribution of corticotropin releasing factor to stress and anxiety responses using pharmacological and genetic techniques in mice. Her program also identifies genetic and environmental contributions to stress behavior and fear learning. By measuring physiological responses to stress (including heart rate and startle reactivity) in animal models and in clinic, her research develops translational probes of anxiety responding and treatment efficacy. The goal of her work is to understand the basic mechanisms underlying anxiety and fear responses, as well as to identify biological factors contributing to the risk of and resilience to development of anxiety disorders. With this information her lab hopes to develop better measures of treatment response in anxiety disorders and identify novel targets of pharmacotherapeutics.

Dr. Tanja Jovanovic, Ph.D.

Tanja Jovanovic, PhD, is an Associate Professor in the Department of Psychiatry and Behavioral Sciences at the Emory University School of Medicine. Dr. Jovanovic has significant expertise in psychophysiological research with traumatized populations, as the focus of her National Institutes of Health postdoctoral fellowship was startle responses in combat-related PTSD. For the last 10 years she has been investigating neurobiological underpinning of PTSD in Vietnam veterans, as well as victims of inner-city violence. Dr. Jovanovic research program focuses on the interaction of traumatic experiences, neurophysiology, neuroendocrinology, and genetics in mental disorders in adults and children in high-risk populations. Her research employs psychophysiological (e.g. acoustic startle response, skin conductance response, heart-rate variability)and neuroimaging (e.g. structural and functional MRI) methods.