Research
For a full list of publications, please see my Curriculum Vitae
Inhibitory circuits in fear acquisition and memory expression
My postdoctoral research has been centered on discerning the cell- and circuit-based mechanisms of fear encoding in the medial prefrontal cortex (mPFC) in mice. Specifically, I was interested in how the dynamic activity of prefrontal interneurons, which have historically been considered to constrain memory, may paradoxically support memory processes. To do this, I combined optogenetics-assisted electrophysiology recordings in mouse brain slices, genetic and viral intersectional cell type-specific labeling, in vivo optogenetic manipulations in specific interneuron Cre-driver mouse lines, and in vivo calcium imaging using fiber photometry. I found that layer 2/3 somatostatin interneurons (SST-INs) play a potent disinhibitory role after fear learning and thus serve to gate fear-dependent rebalancing of prelimbic microcircuitry. Moreover, I found that this disinhibitory role is dictated by cell type-specific interneuron plasticity. Last, I found that prelimbic SST-IN activation not only disinhibits projection neurons in prelimbic cortex but also recruits a specific distributed brain-wide network associated with defensive behaviors.
Examining GABAergic engram neurons
Substantial effort has been invested in discerning the mechanisms governing principle projection neuron participation in memory allocation. However, how interneurons participate in learning and memory processes remains largely unclear. We therefore are investigating how different experiences can be encoded by distinct interneuron populations. We are currently combining activity-dependent neural tagging, intersectional genetics, and in vivo optogenetics to investigate the contributions of specific GABAergic cell types to learning and memory. We are additionally employing in vivo calcium imaging using head-mounted miniature microscopes (Miniscopes) in freely-behaving mice. Such analyses will enable us to observe the evolution of the activity of specific engram cell populations at single-cell resolution across learning, memory expression, and extinction.
Work supported by the Robin Chemers Neustein Fellowship Award
Investigation of prefrontal circuitry controlling the dual expression and inhibition of fear
One line of research I am currently pursuing is to elucidate the circuit mechanisms supporting the apparent fear suppressing/promoting dichotomy in the ventromedial prefrontal cortex. To investigate these functions, I will combine ex vivo electrophysiology, in vivo optogenetics, activity-dependent neural tagging, and in vivo calcium imaging (Miniscope and fiber photometry). The goal of the proposed research is to fully characterize and integrate this novel circuitry into existing models of emotional learning.
Funded by K99/R00 BRAIN Initiative Career Transition Award