This installment of Dissertation Diaries highlights Jodee Frias, a fifth-year Ph.D. candidate in biomedical engineering.
Frias studies the brain using near-infrared spectroscopy, a technique that uses red and near-infrared light to measure blood flow in the brain and measure its responses to stimuli. She describes the technology as “an Apple Watch for your brain.”
Frias’ research focuses on one of the challenges that comes with this approach to technology. Light must travel through the scalp and skull before reaching the brain, meaning the measurements can contain signals from all three. Her dissertation asks how researchers can separate those signals to obtain a more targeted measurement.
“The big question that I’m trying to answer with my research is what is the best and the most robust way that we can separate the contributions from the scalp and the skull and the brain,” she said.
Frias did not originally plan to work in optics. During her sophomore year, COVID-19 made lab work difficult. She reached out to Darren Roblyer, a biomedical engineering professor at Boston University who worked in diffuse optical imaging, and was offered a remote position analyzing existing data.
“I didn’t really know too much,” Frias said. “I just wanted to be involved as an undergrad, and then I started to really fall in love with it.”
By her senior year, Frias was considering pursuing a Ph.D. Roblyer connected her with Sergio Fantini, professor of biomedical engineering, and she eventually joined his lab.
The transition from undergraduate to Ph.D. student was different from what Frias expected. As an undergraduate, much of her time was spent taking classes. In a Ph.D. program, she said, the focus is much more on research, teaching and “creating new knowledge.”
In Frias’ lab, test subjects might complete a short math test, look at a rotating checkerboard or have their blood pressure temporarily changed using blood pressure cuffs. The measurements themselves can take about 20 minutes. Frias then analyzes the resulting measurements using mathematical models and digital signal processing. The instruments record changes in the intensity and phase of light, which can then be used to estimate changes in oxygenated and deoxygenated hemoglobin. Those changes provide information about blood flow in the brain.
Frias has also served as a teaching assistant seven times during her Ph.D. and worked with undergraduates in several different courses, which have become some of her favorite graduate school experiences.
Mentors have also been important to her own experience, particularly as a first-generation, low-income student who did not have a straightforward path to academia.
“I didn’t really have any adults in my life that have taken an academic path at all. So I really found that I leaned on my advisors and my mentors a lot, and that really really helped me,” she said.
At Tufts, she has several people she turns to for different parts of her work. Fantini helps her with larger research questions and planning. Angelo Sassaroli, a biomedical engineering research assistant professor, helps with the technical details of her work. Giles Blaney, a postdoctoral scholar at the Graduate School of Biomedical Sciences, has been another source of advice.
“I lean on as many people as I can,” Frias stated.
Frias also aims to create opportunities for students who are just beginning to explore research. She works with the Tufts University Biomedical Engineering Research Scholars program, which brings high school students to Tufts for a summer research experience. After noting that students tended to arrive with very different levels of laboratory experience, she and other colleagues created a week-long course prior to the program to teach basic laboratory skills and safety. For Frias, the program is partly about giving students enough experience to feel comfortable in a laboratory setting.
Frias’ advice to undergraduates interested in research is to reach out. According to her, graduate students and postdoctoral researchers are often the most useful contacts, because they tend to be the people working directly with students in the lab.
She also encouraged students not to worry too much about bothering graduate students or TAs with questions.
“As someone who has literally been a TA seven times, the students that come and ask me about my research or what I’m doing or what my days look like — it is just above and beyond. I absolutely love it,” she said.
