Meet the PSI Leadership:
Program Directors
Sam King
Program Co-Director
Sam King (he/him) is a 3rd-year MD/PhD student in the OHSU School of Medicine. His research applies computational methods to reproductive biology and the genetic causes of male infertility at the Oregon National Primate Research Center (ONPRC).Sam has mentoring and teaching experience as a lab mentor at Purdue University, a Supplemental Instruction Leader for anatomy and physiology, and a tutor in science and math. He is passionate about encouraging students to explore careers in science and medicine, aiming to make these fields more accessible.
Sofia Vignolo
Program Co-Director
Sofia Vignolo (she/her) is a 6th-year MD/PhD student in the OHSU Biomedical Engineering Graduate Program. Her research focus is on bone regeneration with a clinical application in reconstructive surgery. She has experience in teaching under the Science Made Sensible program at the University of Miami as well as involvement in tutoring and mentorship throughout her career development. She aims to take an active role in inspiring the future generation of researchers to advance their scientific curiosity.
Teaching Assistants
Erin Santos
Senior Teaching Assistant
Erin Santos (she/her) is a 4th-year PhD student in the OHSU Neuroscience Graduate Program. Her research focus is on studying the role of glial cells in regulating neural circuits and their impact on brain function. With an academic background in education, she collaborates nationally to provide mentorship and academic support to underserved communities. Passionate about increasing the accessibility of STEM opportunities, Erin encourages lifelong learning and enthusiasm for science.
Alyssa Granados
Teaching Assistant
Alyssa Granados (she/her) is a 3rd-year PhD student in the OHSU Biomedical Sciences Graduate Program, focusing on immune-cancer interactions in lung cancer. She brings extensive mentoring and outreach experience, from virtual tutoring during COVID to guiding undergraduate researchers and volunteering with OnTrack and PSI’s mentor team. Alyssa is passionate about supporting students on their path to reach their goals, fostering interest in science among young learners, and breaking down barriers to scientific careers.
Ruhika Prasad
Teaching Assistant
Ruhika Prasad (she/her) is a 3rd-year medical student at the OHSU School of Medicine and an alumna of the PSI program, where she was first introduced to research in high school. She later studied Alzheimer’s disease in mouse models during college, and most recently was a 2024–2025 NIH Medical Research Scholar, where she focused on how maternal factors influence microbiome transfer at birth. Ruhika has also supported first-year medical students as a tutor and is deeply committed to mentorship, health equity, and uplifting the next generation, especially through programs like PSI that helped shape her own path.
Kevin Elk
Teaching Assistant
Kevin Elk (he/him) is a 3rd-year PhD student in the OHSU Neuroscience Graduate Program. As a member of the Mishra Lab, he is currently studying the molecular mechanisms underpinning the regulation of blood flow to the brain. Kevin is passionate about teaching and is committed to increasing the presence of underrepresented voices in STEM. He believes that in addition to providing information about our natural world, effective science education can develop skills in collaboration and critical thinking, and foster curiosity for life.
Hoa Trinh
Teaching Assistant
Hoa Trinh (she/her) is a 4th-year PhD candidate in the OHSU Neuroscience Graduate Program, working in Dr. Marc Freeman's lab at the Vollum Institute. Her research focus is on understanding how neurons undergo developmental remodeling through retrograde death signaling, and how perturbing this signaling affects neuronal survival during development. As a first-generation student, Hoa is passionate about mentoring high school and young scientists and building inclusive scientific communities, drawing on her own experience to help others navigate the field without a built-in roadmap
Ashley Anderson
Teaching Assistant
Ashley Anderson (she/her) is a 2nd-year PhD student in the OHSU Neuroscience Graduate Program. Her research focus is on understanding how different neuronal cell types form and maintain synapses in healthy and disease states. She has previous mentorship and teaching experience in science fields such as chemistry, psychology, and neuroscience, and she continues to mentor peer graduate and high school students throughout her graduate training. As a future educator, Ashleyis dedicated to helping pave the road for young trainees to reach their personal and professional goals, and to increasing participation from underheard communities in STEM.
Navah Eshragahi
Teaching Assistant
Navah Eshraghi (she/her) is a 2nd-year medical student at the OHSU School of Medicine. She brings research experience with focuses such as therapies for pediatric sarcoma, vision care for glaucoma patients, and climate studies. During her undergraduate years at the University of San Diego, Navah chaired the Learning Communities program and enjoyed providing mentorship for students transitioning into their college curriculums. As a PSI alumna, she is excited to return and support high school students in gaining early exposure to sc
Kate
Halverson-Kolkind
Teaching Assistant
Kate Halverson-Kolkind (she/her) is 2nd-year MD/MCR student at OHSU and a former PSI student. Prior to medical school, she spent nearly seven years studying cataract formation and lens protein biology, contributing to multiple peer-reviewed publications. In addition to her research experience, Kate has worked in clinical care and has extensive experience tutoring and mentoring students across a wide range of subjects and educational levels. She is passionate about fostering scientific curiosity and supporting the next generation of researchers.
Faculty Support
Ramon Barajas, M.D.
Faculty Sponsor
A neuroradiologist and physician-scientist, Dr. Barajas now co-leads the BBB Program with Dr. Muldoon following Dr. Neuwelt’s retirement. His research focuses on advancing tumor-specific drug delivery through innovations in imaging and a deeper understanding of the tumor immune-metabolic microenvironment. Dr. Barajas is committed to fostering an inclusive research environment and mentoring the next generation of physician-scientists.
Leslie L. Muldoon, Ph.D.
Faculty Sponsor
An Associate Professor of Neurology and Cell, Developmental and Cancer Biology, Dr. Muldoon has directed the BBB program’s preclinical research labs since 1990. Her collaborative work continues with Dr. Ramon Barajas on novel MRI-based strategies to better understand and treat brain tumors. Dr. Muldoon has been a longtime supporter of the PSI program with the goal of making scientific careers more accessible.
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Lisa Muir, MPA:HA, CCRP
Program Support Coordinator
A Certified Clinical Research Professional with a B.S. in Molecular Biology and a Master’s in Public Health Administration, Lisa has been with the Blood-Brain Barrier Program for over two decades. She oversees the grants, contracts, and finances supporting the program’s NIH- and VA- funded preclinical and clinical research. She also provides essential administrative support for the PSI Program, helping coordinate the many moving pieces that keep the program running successfully each year.
Previous leadership:
The PSI program has an extensive history spanning over two decades, previously directed by a distinguished line of individuals: James Rosenbaum, MD, Edward Neuwelt, MD, Richard Rosenbaum, MD, Tammy Martin, PhD, Leslie Muldoon, PhD, DreeAnna Morris, BS, CPIA, & Hayleigh Ast, ND.
Past Teaching Assistants (TAs):
We also want to acknowledge the contributions of our past TAs who played a vital role in shaping the program's success: Viviane Cahen, MD, Brittny Flynn, MD, Lola Sosanya, Madison Hupp, Peter Tran, Arthi Inagandla and Kareem Woods.
We are always looking for more TAs and
support, so email us if you are interested!