From electrical engineering to the inner ear: how Radha Kalluri, PhD, uses the physical sciences to address otolaryngology’s most pressing issues

“What do you want to be when you grow up?” Parents, teachers, relatives, and friends ask this question over and over as one transitions from childhood to adolescence, from adolescence to adulthood, like the refrain in a song that plays again and again on the radio. But for Radha Kalluri, PhD, this question often was not external but internal, a litmus test for each decision she made as her studies and career advanced. She was driven by a passion for learning and an interdisciplinary set of interests that have come to define her approach to the cutting-edge research in her laboratory.

Kalluri grew up in a loving family in Lowell, MA after her parents emigrated from India when she was eight years old, and though her father was a professor in electrical engineering, she initially thought that she wanted to be a lawyer, competing in mock trial in high school. She was undecided on her major when she entered college and ultimately entered the college of engineering at the University of Massachusetts at Amherst in large part because it would leave most doors open for her after college (not to mention that it was one of the few majors where students could begin working with their hands in project-based labs as early as freshman year). After college, when Kalluri was interviewing for jobs as an electrical engineer, she still found herself wondering what she wanted to be when she grew up, realizing that she wanted to study more and learn more before she made that decision.

As Kalluri completed her MS in Electrical Engineering/Electrophysics at the University of Southern California and then her PhD in Health Sciences and Technology at the Massachusetts Institute of Technology, she began delving into readings about neuroscience, biology, and retinal implants, and as a postdoctoral fellow in Cellular Biophysics at Harvard Medical School, she shifted her focus once more, participating in a program where physically-trained scientists explored biologically-relevant questions. “If only I could study a little longer, I would know enough to be useful,” she kept thinking at each step, eventually falling in love with the intricacies of the inner ear. Thankfully, given that Kalluri’s older brothers had already pursued their PhDs, her parents understood that the process would be long and arduous, giving their daughter their full support.

Kalluri’s seemingly unconventional trajectory into the field of otolaryngology actually makes perfect sense, as the ear is perhaps the most engineering-friendly organ in the sensory system, with the exterior ear’s intricate acoustics impacting how sound propagates into the inner ear, which itself functions by using a hydro-mechanical system. Thus, the study of the ear offers a sort of ideal compromise for someone intrigued by the nexus of the physical and biological sciences, combining mechanical engineering and electrical engineering in a biological system. More specifically, Kalluri’s research centers on hair cells in the inner ear, which take mechanical information about sound and balance and convert that into signals that can be received by neurons. These neurons then communicate those signals to the brain, which interprets the information. There are several different types of hair cells and neurons that are responsible for translating these mechanical signals into neural signals, but not all neurons are created equal–some are particularly vulnerable to damage (which can negatively impact hearing and balance), while others are much tougher and more resilient to damage. Kalluri hopes to identify the signaling pathways that protect neurons from damage, and by applying her knowledge of the mechanical and physical sciences to this specific biological issue, she aims to contribute to developing innovative approaches to addressing hearing loss and balance problems that do not currently have a solution.

To this end, Kalluri’s lab emphasizes the interplay between quantitative analysis, theoretical modeling, and experimental neuroscience as one of the most promising ways to approach these issues. This synthesis of approaches is especially important to her since “theoretical modeling not grounded in real data can lead you wherever you want to go…in the end, our desire as a field is to understand the field as it is or is not working in reality, not just theoretically.” Meanwhile, experimental neuroscience is constrained by what one can realistically accomplish in the lab and by errors that are an inevitable part of experimentation, but that’s where theoretical modeling comes in, as it can allow for extrapolation of information that would not be achievable just through experimental neuroscience alone. Kalluri’s three-pronged approach means that her lab is able to understand how their data is collected, which gives better context for which parts of the data may be worth analyzing and which might simply be the result of an experimental error.

On a broader scope, Kalluri prioritizes the intersection between basic research and clinical practice, an intersection that is a significant strength within the USC Caruso Department of Otolaryngology-Head and Neck Surgery. Through her connection with the clinical department and her physician-scientist colleagues as well as the many talented graduate students who have worked in her laboratory, Kalluri is able to appreciate how findings in the lab are translated into the clinical setting–she notes that “the passion of the students coming to study with us and being housed in a clinical department keeps the rigor of the basic science well-grounded. In the long run, our work should be impactful to patients, and not all basic science laboratories have that component.” Kalluri believes that her interactions with students help to achieve this mission: “If I just had trained scientists working on my vision, my lab would be unidimensional.” Conversely, with students, the mission of the lab changes, as the goal is to train students to have their own ideas and therefore the lab’s principal investigator needs to be open to novel approaches.

When Kalluri was asked about what advice she would give to students from underrepresented backgrounds who may be interested in pursuing a career in scientific research but feel intimidated or worried about imposter syndrome, she passed along a few pieces of wisdom that her father had shared with her early on: “Don’t tell yourself you can’t do something–let others put up those barriers for you. And if there’s something you’re interested in, reach out to somebody and ask them about it. In fact, reach out to them twice, at least.”