Science three questions

Minding the Brain: Professor Mehrdad Jazayeri on brain models research, the HHMI award, and the growth of neuroscience

Jazayeri: “Neuroscience is a really big, interdisciplinary field, resembling a giant monster with many legs. Currently, it’s at a very interesting stage of development along several directions.”

Mehrdad Jazayeri, Professor of Brain and Cognitive Sciences at MIT, has recently been named an HHMI Investigator for his research on the mind-brain connection. Earlier in the year, he also received the Vannevar Bush Faculty Fellowship. Both awards are notable for allowing researchers to pursue ambitious projects. Having immigrated from Iran and pursued his academic journey at NYU and the University of Washington, Jazayeri's research at MIT combines cognitive science, neuroscience, and machine learning to connect the biological mechanisms of the brain to the computational capacities of the mind. 

Professor Jazayeri sat down with The Tech to share the story of his path to MIT and his visions for the future.

TT: How far back does your interest in neuroscience extend?

Jazayeri: Iran didn't have, at the time, faculty in neuroscience, so I didn't know anything about neuroscience. I was an electrical engineer as an undergrad, but at heart, I wasn't a pure engineer. After finishing my undergrad, I decided to leave the academic environment and go to work, and I had a few years of doing a variety of different things: a few years of carpentry, a few years of farming. The farming years were very formative. During those years, I was able to learn about neuroscience through books that my uncle and others sent from abroad. I didn't necessarily have a direct interest in biology, but I definitely was intrigued by the mind. I received a bunch of books from my uncle on the topics of neuroscience and consciousness, and that really was the hook. I fell in love.

Everything we do shapes our future experiences one way or the other, depending on the path we take. All of those engineering skills I acquired in Iran have come to really shape the way I think about scientific questions. I want concrete answers. I want quantitative, rigorous explanations. And that's an engineer's mind. I'm not saying it's only engineers that have this mind, but I definitely learned it through that path, and I think that's a really valuable skill. 

TT: What does your research process look like, and how does HHMI support it?

Jazayeri: The goal of our department, which is very much aligned with what my lab does, is to understand how the brain gives rise to the mind. We start with research questions such as, ‘How do we think?’ and ‘How do we make sense of the complex world around us?’ Tackling these questions is hard. A key requirement is to do experiments on animals where we can answer these questions mechanistically. But working with animals is challenging. First, there must be a good justification. Second, even when there is good justification, it is hard to know what animals are thinking since we cannot talk to them. So we come up with creative ways to teach them how to communicate their thoughts. When we have a suitable animal model, we start looking into what the brain does by recording the activity of tiny neurons inside their brain. The most challenging step comes next when we try to connect signals in the brain to the computations of the mind. Neurons communicate with one another using obscure electrochemical signals. Trying to understand what they say is like breaking a secret code. We tackle this problem by building computational models. These models let us use the language of mathematics to decipher the code. Finally, we must validate our models and hypotheses. Sometimes, things work out nicely. Most other times, the validation step proves us wrong and forces us to go back to the drawing board. And that cycle continues.We are getting now to some really deep and interesting cognitive aspects of behavior at the level of neurons. Some of these problems are really hard to solve and require that you don't have to be bound by day-to-day productivity. It requires white space. HHMI has always been amazing at recognizing this need and giving the support, community, and infrastructure to answer difficult scientific questions.

TT: What are you looking forward to in this field?

Jazayeri: Neuroscience is a really big, interdisciplinary field. It's one giant monster with many legs and it’s at a very interesting stage along several directions. The need for modeling is very, very clear now. People who think from an engineering or mathematical perspective, including many of my colleagues at MIT, think deeply from that perspective.

When I was a PhD and postdoc, the existing technology allowed us to record two, three, four neurons a week. Now, any student in my lab can record hundreds of neurons a day. So that means that you now can ask really difficult questions and have the data to test complex models and hypotheses.

Another big advance is our ability to build models at scales that they can mimic behavior, thanks to the advances in the past decade in machine learning and artificial intelligence. Making measurements inside the brain is challenging, so if you have a good model of the system, then you can pressure test your analyses and investigations using those models. The advances in technology and our ability to build realistic, large-scale models that display natural behaviors are key to helping mathematics do its magic.

I remain deeply curious, and there's a ton of questions that I want to answer. But as I'm getting older, I'm also realizing that my life is limited. I feel inspired to motivate others and train others to keep the flag going, because I feel like they can multiply the objective in a much more effective way than I can do personally.

One thing at the core of my DNA is that I enjoy the process of discovery more than the goal. The key is to have a curious mind that wants to find the truth more than the truth itself. You know you have it if you go to bed thinking about it, wake up thinking about it, and you don’t get tired. These people get their teeth into the heart of the problem and they really enjoy what they're doing.