By Michelle Jaffee; photos by Jackie Hart
Tracy Centanni Rosen, Ph.D., is an associate professor of speech, language and hearing sciences at the University of Florida’s College of Public Health and Health Professions. Her research aims to better understand the root causes of dyslexia and spur neural plasticity, or the brain’s ability to adapt, using noninvasive vagus nerve stimulation to improve reading and language skills.
Q: What is the most exciting discovery you’ve made so far?
A. I’m most excited about my lab’s progress in testing vagus nerve stimulation as a potential future therapy for dyslexia. In a roundabout way, this stems from my Ph.D. studies. My mentor at the University of Texas at Dallas, Dr. Michael Kilgard, is a pioneer in the field of vagus nerve stimulation, and I was fascinated by the ability to rewire the brain, even post-injury, even in adult animals, with just a little bit of electrical stimulation and training. At the time, I was learning about a surgical form of VNS being tested for tinnitus and motor impairments. We were also looking at how the rat brain encodes sounds, and at one point, we had a guest lecturer from the University of Connecticut, Dr. Joe LoTurco, who was studying genes associated with dyslexia and brain development. I asked him, ‘what does this mean functionally? If the neurons are not where they’re supposed to be, what does this mean for behavior and perception?’ He offered to send me animals to run behavior experiments, and this became my dissertation. For many years, researchers had been hunting for a single gene for dyslexia, but we demonstrated it’s not just one gene: There are two neural-migration genes on the same chromosome that have different impacts. During my two postdocs, at MIT and the MGH Institute of Health Professions, I replicated this work in humans and found the same relationships. Then, as noninvasive vagus nerve stimulation approaches became available, I was able to apply my knowledge to a new population. This has paved the way for our upcoming clinical trial testing noninvasive vagus nerve stimulation in dyslexia.
Q: What inspired you to focus on this area of neuroscience?
A. At Penn State, where I went to undergrad, I originally thought I wanted to study forensic psychology and criminal profiling. As a psychology major, I was looking for research experience, but the only lab with openings at the time was focused on brain recordings and vision perception. I remember feeling intimidated, having come off a not-great experience with chemistry and calculus. I told the professor I thought it might be too much. But with his encouragement, I joined a newly launched project, aimed at replicating a music-training study using EEG. Music was something I knew: I was in both drum and bugle corps and also marching band all four years, playing French horn and mellophone. I thought, ‘I can do this.’ I’ll never forget the moment I first saw the little squiggles go across the screen and thought, ‘this is someone’s brain.’ It was the coolest thing I’d ever seen. So I switched to neuroscience. Then, my senior year, my paternal grandmother had a stroke and experienced severe aphasia. She was frustrated trying to communicate. So I returned to college thinking, ‘I’m going to figure out how we can use music to rehab language post-stroke, because we know language and music are connected.’ Fast forward to my Ph.D. program: The lab I joined was an animal model lab, so studying aphasia wasn’t an option since rats don’t have language. But with the serendipitous visit from the UConn professor, I found my way to dyslexia.
Q: How do you envision your research advancing neurological disease treatments?
A. We have seven active projects in our lab, from the brain basis of dyslexia to speech and noise perception in veterans with traumatic brain injury. We’re testing treatments for age-related hearing loss in older adults, and we’re also collaborating with Brooks Rehabilitation on post-stroke aphasia, a project that’s brought me full circle to my original goals. And this fall, we’re enrolling young adults with dyslexia in a clinical trial testing noninvasive vagus nerve stimulation as a potential therapy.
Q: What makes working in your lab different from other research environments?
A. I’m most proud of our array of techniques in tackling research questions. We use EEG and functional MRI, and I’ve been trained in MEG (magnetoencephalography) and microelectrode recordings as well. We do work in young kids, young adults and now older adults too. So students in my lab are exposed to various clinical populations as well as various neural imaging techniques. Currently, we have two postdocs and three Ph.D. students, and at any given time, we have about 10 undergrads. One undergrad honors student who is dual-majoring in psychology and music is preparing to test vagus nerve stimulation to improve pitch perception or rhythm entrainment, which is your ability to tap along with a beat. These are super fundamental skills that are important not only for music but also for speech and language.
Q: What do you enjoy doing outside of work? A. I grew up riding horses, and this has come back to me recently. I also love to travel, and to me, travel means adventurous eating. At conferences, if you come to dinner with me, be prepared: You’re going to eat the craziest thing the local town has to offer. The only thing I won’t eat? Live bugs.
