Fishman Lab | HSCRB

Mark C. Fishman, M.D.

Mark C. Fishman’s group studies the heart-brain connection. They employ a range of genetic, developmental, and neurobiological tools in zebrafish to understand what the heart tells the brain, and how critical internal sensory systems adjust homeostatic and somatic behaviors, including social interactions.

Emily Voce

Emily Voce is the Administrative Lab Manager for the Fishman and Hsu labs.

Postdoctoral Fellows

Sara Lelek-Greskovic, Ph.D.

In my current work as a postdoc in Fishman and Engert labs I will focus on the characterization of the brain-heart communication. Previously I was working on the zebrafish heart regeneration and the cellular response to the heart injury.

Shachar Sherman, Ph.D.

Nikolai Hoermann, Ph.D.

Soma Singareddy, Ph.D.

Did you know that the heart has its own “brain”? I didn’t! Given my doctoral training as a classical ion-channel electrophysiologist specializing in the cardiovascular system, I found this revelation more exhilarating than embarrassing. So, I joined the Fishman-Engert Group in March 2022 to investigate what (if) this intrinsic cardiac nervous system (ICNS) is sensing and how (if) it communicates. I use physiological and engineering techniques to explore the molecular and cellular intricacies of heart(-)brain communication. I mostly probe live baby fish hearts. Once in a while, I do ePhys on zebrafish cells in and ex vivo.

Kristian Herrera, Ph.D.

I am interested in how brains evolve to cope with new environments. An animal’s brain continuously integrates external sensory cues with information about the animal’s internal physiological state to generate behaviors matched toward the animal’s immediate needs. As they move into new environments across evolutionary timescales, natural selection leads to the emergence of new sensory and internal physiologies that are suited for their new conditions. For these changes to be truly adaptive, the brain must correspondingly change how it balances and integrates these evolving cues. Using various fish models, I am trying to identify any generalizable principles that might facilitate the coordinated evolution of these complex systems.

Luis Hernandez Nunez, Ph.D.

I am a postdoctoral fellow at the Fishman and Engert Labs. I study the heart-brain communication axis from a systems-level perspective in larval zebrafish. With a multidisciplinary approach that incorporates genetics, cellular physiology, control engineering, and computational neuroscience, I hope to uncover the neural circuit mechanisms underlying cardiac control. I also study how cardiac state modulates brain function and ultimately behavior.

Yasuko Isoe, Ph.D.

I am a post-doc in the lab of Florian Engert. My research interests are in the ontogeny and species-diversity in the social behavior. I am comparing the social behavior of zebrafish and medaka, fish which, as adults, show very different collective behaviors. I have found behavioral differences even as larvae. The relative simplicity and transparency of the embryos permit me to model the behaviors and to use cellular imaging to dissect the underlying neural activity. My hope is that these experiments will illuminate the mechanisms and evolutionary diversity of social decision-making.

Roy Harpaz, Ph.D.

My research at the Engert Lab focuses on understanding how brains generate natural and complex social behaviors. Specifically, I use behavioral analysis, functional imaging and mathematical modeling to study the neural circuits underlying social behavior in wildtype and mutant zebrafish over development. The results of my study will allow me to understand how complex social behaviors are represented in the brain and to link genetic mutations that effect social behaviors to changes in these neural representations.