Robert Rozeske

Our research team investigates how traumatic experiences modify the neuronal circuits responsible for memory formation, and how these alterations oppose or promote flexible defensive behaviour during future challenges. To deduce the function of complex brain circuits, we use a multi-method approach to record behavioural and neurophysiological data streams in parallel. This vertical data organization allows us to link the temporal dynamics of fear behaviour with neuronal circuit activity at several levels. Our group combines fiber photometry, microendoscope calcium imaging, single unit electrophysiology, 3D behavioural tracking, and intersectional optogenetic techniques to understand how neuronal circuits interact to: (1) identify a context as either threatening or safe and (2) generate fear, avoidance, and anxiety behaviours in threatening contexts. This approach will reveal the neuronal circuit activity responsible for emotional behaviour and establish a path toward novel therapeutics for mental illnesses such as post-traumatic stress disorder.   

I received my PhD under the supervision of Dr. Steven F. Maier from the University of Colorado-Boulder. During this period, I studied how the psychological dimension of behavioural control over a stressor engaged the prefrontal cortex to produce resistance to subsequent challenges. While at INSERM (Bordeaux, FR) with Dr. Cyril Herry for my postdoctoral studies, I examined how activity within the prefrontal-periaqueductal gray circuit produced context fear discrimination. I continued to study context representations in Dr. Mark Brandon’s laboratory at McGill University, where I examined how the hippocampus dynamically builds spatial maps to represent threatening and safe contexts. In April 2021, I will open my systems neuroscience laboratory in the Department of Psychology at the University of Toronto Scarborough to investigate the neuronal origins of emotional behaviour.