Bahati Nkera

Bahati Nkera

Graduate Student

Bahati Nkera

Joshua Speiser

Bahati Nkera is a 5th year graduate student working in the Barnea lab

Carney Institute (CI): Tell us a bit about yourself.    

Bahati Nkera (BN): I was born in the Democratic Republic of Congo. Due to the war, my family and I immigrated to the United States when I was about four, staying in the Boston area. From the time I was young, my parents - particularly my dad, who worked in healthcare in Africa but had to start all over when he arrived in the states - always instilled in me the value of having a good education. In his free time, he used to take us to libraries, so my siblings and I gravitated towards knowledge, books and learning in general. Now, whenever I go to a new city, I always try to check out their library. 

At the same time, my parents were both very social people and welcomed a lot of family into their home. I remember just being around a lot of people at a young age, family and friends, and I was always a very curious and social person, wanting to talk to everyone. I think that instilled in me a passion for psychology because I was always asking "Why do people act the way they do? What drives them? What motivates them? What makes them tick?" 

This curiosity and a love of science eventually led me to study neuroscience. I went to the University of Massachusetts, Amherst for undergrad where I double majored in biochemistry and psychology in a neuroscience track. At UMass, I was able to bridge the gaps of hard science - like the molecular side of things, proteins with biochemistry - with neuroscience and behavior. And I'm still pursuing those abstract concepts, such as motivational drives and behavior, but from a scientific biological viewpoint.   

In my sophomore year, I joined a neuroscience lab through a STEM diversity program that provided research opportunities for undergraduates. Then, in the summer after my junior year, I went to Purdue University to do research in a Parkinson's disease lab where I discovered neurodegeneration and its connection to mood and affect. After graduation, I landed another research internship, this time at Oregon Health and Sciences University’s Vollum Institute. My research there was more focused around behavioral neuroscience, specifically looking at delayed discounting and impulsivity in rats through behavioral paradigms.  

After graduating, I applied to the neuroscience program at Brown in part because the university has a great diversity recruitment program for POC Ph.D. students. When I visited the university, I was blown away by the amazing science being done here.  

CI: Upon arriving at Brown, did you immediately settle into a research path, or did it take some experimentation?  

BN: When I was applying to neuroscience programs, I told myself the two areas of research that I didn't want to do: vision and olfaction, because I thought that they'd been well studied and well characterized. I really wanted to focus more on cognitive and clinical neuroscience. However, a cohort mate who was rotating in Gilad Barnea’s lab – an olfaction centered lab – said, "You should think about rotating in the Barnea lab. They’re asking many cool, interesting questions that go far beyond in a way that you might be interested in."  

So, I took a leap of faith, and I ended up joining the lab and loving it! The environment is electric. I'm working on establishing trans tango in mice and really thinking about circuits in the brain. My other main project is studying pheromone signaling in mice and how knocking down a specific pheromone receptor affects innate behaviors. So, it's olfaction in that way, but it's still in the realms of behavioral and circuit neuroscience. And the lab has been so supportive. I've been able to grow both as a scientist and as a person.   

CI: How has your research on pheromone signaling overlapped with the work that the Barnea lab has done on retro-Tango? 

BN: For now, they're running on different tracks but more and more I do foresee overlap. I think the goal would be to see if we can establish retro tango in mice - which allows us to visualize a circuit in a way that we haven't been able to do until recently - to map some of the circuits that are involved in pheromone signaling. I think the thing that does currently overlap are the techniques that I’m employing, e.g. using  immunochemistry, perfusion, or dissections. And the overall intellectual thought and the critical thinking, in terms of planning experiments or determining what assay to utilize, is fully applicable to my work. 

CI: When you look at animal studies, how much of these are relatable to the human system?  

BH: I think it depends on what kind of field of neuroscience you're in. In animal research there’s what may be called a "translatability crisis." I think less than 50% of animal findings translate to humans. I study olfaction and in humans, olfaction is one of the least used senses. Mice, for example, have a chemosensory system with a specialized organ - the vomeronasal organ - that perceives, and processes stimuli related to social and reproductive behaviors. In humans, this organ is vestigial. 

So, this begs the question of what inferences can I actually take from my research on pheromones where mice are the test subjects? You can definitely learn how sensory systems work and how sensory stimuli are processed. But this creates new lines of questioning like "How is the information gleaned from olfactory stimuli, relayed and propagated to higher order of brain regions?" That’s in part why I’m studying what happens when you disturb one part or one node in this sensory circuit and then, in turn, the downstream behavioral or physiological ramifications.  

I’m seeing some super cool stuff with my research so far. Specifically how deleting a receptor important for pheromone signaling leads to downstream behavioral changes in parenting. For example, in male knockout animals - which are mice that carry two copies of the deletion - there is a switch in parenting behavior. Wild-type males, typically attack and kill pups that aren’t their own but our knockout mutants seem to retrieve and crouch over these pups, which is something they normally don’t do. Further, we see differences in our mutants when we vary the quality of the parents that raised them.

A lot of this work is relatable to the nature versus nurture inferences that have long been discussed in human biology, specifically looking at innate behaviors that are hardwired into us but then begin to shift as the environment changes. It goes back to some of the studies of twins - how twins reared apart end up having similar IQs - that piqued my interest and made me fall in love with psychology and neuroscience early on. 

CI: As you look longer term, what shape do you see your career taking?  

BN: I have an answer that always surprises people in a way. I'm planning to go to medical school to study psychiatry. I think I realized midway through my Ph.D. that I wanted to have a clinical component of treating people and helping them out, alleviating their burdens, but also studying psychiatric disorders. And luckily, I've talked to my mentor and he's super supportive about that. 

People often ask me "Are you sure you want to do this?" but there are more and more programs popping up for medical school programs for people who just finished their Ph.D.'s. Circling back to the beginning of our conversation, I think that ties back into my parents. My dad, when we immigrated here, he had to restart his career. He was in his early thirties and then it took eight years or so to get reestablished. I'm only 28 so what's four more years of school? My dad did it, worked hard and made so many sacrifices so I could have all these opportunities. I think it's important to strive for your professional goals and not settle, because it’s familiar or easy. I know I have the time. I know I have the resources, and I'm just going to keep on fighting for my dream.