César Javier Hernández, B.S., M.S., Physiological Systems (PSYS) Graduate Student
Since earning both my bachelor degree in Psychology and my master degree in Neuroscience from Universidad Nacional de Colombia in Bogotá, I have been interested in synaptic plasticity mechanisms. In my masters work, I researched regulation of dendritic spine morphogenesis by PINK1 in mouse hippocampal cultures. Now, I am pursuing a doctoral degree at UMD thanks to one of the Fulbright Colombia Commission Scholarships awarded in 2020. In the Speer lab, I focus my research on the synaptic organization of inhibitory amacrine cell input to ON⍺ retinal ganglion cells. My experimental approach to studying retinal circuit inhibition takes advantage of conditional knockouts of scaffolding proteins that cluster glycine or GABA(A) receptor subunits together with expansion microscopy (ExM) for high-resolution fluorescence imaging.
Tarlan Vatan, B.S., Neuroscience and Cognitive Science (NACS) Graduate Student
I obtained my Bachelor of Science in Biology from the University of Maryland in 2020. As an undergraduate research assistant in the Speer lab, I successfully tested and implemented a protocol to perform tissue imaging using Expansion Microscopy (ExM). My research interest is understanding how spontaneous activity during development drives proper wiring of neural circuits. I am interested in studying the underlying molecular mechanism of this spontaneous activity-dependent eye-specific segregation by looking at synaptic organelles, specifically mitochondria and ribosomes. I am using super-resolution imaging (STORM) of synapses and live imaging of axon trafficking to characterize how mitochondria and ribosomes are affected by disruptions in retinal wave activity.
Collin Lee, Undergraduate Student in Neurobiology and Physiology
I am currently a sophomore majoring in Biology with a specialization in Physiology and Neurobiology. I am also in the University Honors program. My research interests include using imaging techniques to see how the synapses connecting each eye to the brain develop in mice. Currently, I am studying how different drugs, like epibatidine and forskolin, impact activity-dependent plasticity of synapses in the dorsal lateral geniculate nucleus of the brain.
Rebecca Pomerat, Undergraduate Student in Neuroscience
I am currently a senior majoring in Neuroscience with a focus on the Molecular, Cellular, and Physiological track and am a member of the Neuroscience Honors Program. My research interests focus on how intrinsic cellular properties and signaling pathways guide the development of visual circuits. My current thesis project investigates how intrinsic light sensitivity and PACAP signaling regulate the development of intrinsically photosensitive retinal ganglion cell (ipRGC) axon projections. I plan to examine axon projection patterns at both the population and single-cell levels, providing insight into how specific molecular signals influence the wiring of visual pathways during development.
Principal Investigator
Colenso M. Speer
Associate Professor, Department of Biology
Director, BISI Graduate Program Physiological Systems Concentration Area
Faculty member:
Brain and Behavior Institute (BBI)
Biological Sciences Graduate Program (BISI)
Program in Neuroscience and Cognitive Science (NACS)
I am privileged to pursue my passions for structural imaging, neuroscience research, and teaching. I am excited to support the next generation of neuroscientists and help them achieve success in their independent careers. Together, we are working toward exciting new discoveries that advance our understanding of visual circuit development, plasticity, and dysfunction in blinding diseases.
PREVIOUS Members
Postdoctoral fellows
3.) Rashmi Rashmi, Postdoctoral Fellow (2021-2025)- Research Associate, Northwestern Medical School
2.) Joe Pottackal, Postdoctoral Fellow (2021-2022)- Health Specialist, National Institute on Aging at the NIH
1.) Swapnil Yadav, Postdoctoral Fellow (2021-2022)- Senior Data Scientist, Walmart Global Technologies
Graduate students
5.) Chenghang Zhang, Biophysics (BIPH) (Ph.D., 2023)- Postdoc with Anitha Pasupathy, University of Washington
4.) Jaqueline Minehart, Neuroscience and Cognitive Sciences (NACS) (M.S., 2023)- Account Manager at Zeiss Microscopy
3.) Theresa Alexander, Computation Biology, Bioinformatics, and Genomics (CBMG) (Ph.D., 2023)- Quantitative Biologist at Amgen
2.) Shyrice Mitchell, Molecular and Cellular Biology (MOCB) (M.S., 2021) - Associate Director at Aragen Life Sciences
1.) Kyle Fisk, Neuroscience and Cognitive Sciences (NACS) (M.S., 2020)- Imaging and Sales Specialist at BioVision Technologies