By Michelle Jaffee; Photos by Nate Guidry
Freddyson Martínez-Rivera, Ph.D., is an assistant professor of neuroscience at the University of Florida’s College of Medicine. His research aims to broaden understanding of fundamental aspects of adaptive as well as dysfunctional behaviors in conditions such as substance abuse, impaired decision-making and mood-associated disorders.
Q. What inspired you to focus on this area of neuroscience?
A. As an undergrad at Inter American University of Puerto Rico, San German, I started out taking education classes to become a teacher. I was the first in my family to go to college. I had to decide what type of teacher I wanted to be, so I started taking biology classes because I liked science. I discovered I liked it so much I switched to a biology concentration. I was always very curious about the basic components of our living bodies. This led me to internships at UC San Diego and Harvard and eventually a Ph.D. program at the University of Puerto Rico School of Medicine. I rotated in different labs and was particularly drawn to pathways of neuropsychiatry and addiction.
Q. What’s the most exciting discovery you’ve made so far?
A. In my formative Ph.D. years, there was one in which we used deep brain stimulation in a rat model to reduce drug seeking. We found that when you use a specific low frequency of stimulation in a brain structure associated with pleasure, reward and addiction, you can reduce drug-seeking behavior and associated memories. However, when we set the parameters differently, as if treating Parkinson’s disease in people, it actually increased seeking behavior.
Q. How do you envision your research advancing neurological disease treatments?
A. Our lab is studying exposure-based therapy approaches called extinction training. In drug-seeking behavior, there is an association with cues and the environment. In a rodent model, we present those cues but in the absence of the drug. The animals start receiving ‘exposure therapy,’ and they start managing these urges triggered by the cues. And then we measure the activity of cells and genes in relevant brain regions and correlate genetic patterns with those specific phenotypes. We are also studying models of depression, for example using bullies and social distress. Some develop coping behaviors, while others develop social avoidance and self-isolation. And then we apply exposure-based training to mitigate neurobehavioral changes, analyze their genetic profiles and potentially identify targets that we can pharmacologically modulate to relieve these maladaptations.
Q. What makes working in your lab different than other research environments?
A. I have learned so much from my mentors and continue to learn from them. I try to take a little bit of everything that has or hasn’t worked for me and share that with my students. I challenge them, always asking, ‘what is the rationale behind that?’ ‘Why are you doing that?’ I tell them, ‘We are learning together. You are learning from me, and I am learning from you.’ My style is to set a very friendly tone. We have lab meetings and journal clubs to talk about science and critical thinking, where they also practice their writing skills, which is very important for young scientists.
Q. What do you enjoy doing outside of work?
A. Spending time with my wife and 7-year-old twins, a girl and a boy, and playing chess, biking, playing or watching basketball, having movie nights, talking on the phone with my dad, brother or friends and visiting family in Puerto Rico.