The human brain is only three-pounds of biological tissue, yet it is the source of all our perceptions, thoughts and movements. Every word spoken, every invention realized, every touch of a soccer ball – is a testament to the great capacity of the human brain.
The brain remains profoundly mysterious. From how it processes pain to why it becomes diseased to the origins of consciousness, questions remain about virtually all of its structures and functions, which continue to perplex scientists.
In recognition of the immensity and importance of this challenge, the University of Chicago has launched the Grossman Institute for Neuroscience, Quantitative Biology and Human Behavior, which aims to build new cross-disciplinary collaborations focused on understanding the brain and human behavior.
We previously spoke with John Maunsell, PhD, distinguished neuroscientist and inaugural director of the Grossman Institute, to learn more about his vision for neuroscience research at the University of Chicago. In the second part of our Q&A, we discuss his motivations as a young neuroscientist and the one question about the brain he’d really like to know the answer to.
So what made you want to study the brain?
I’ve been interested in biology and research since middle school. When I was growing up, there was a lot of emphasis was on ecology. I went to Duke University in part because they had a marine laboratory with an emphasis on marine ecology. I loved the setting, but I felt that it was perhaps not the most challenging biology that I could do. The more I was at this beach atmosphere, the more I started thinking, what are the other opportunities in biology?
When you start thinking about the big challenges in science, it doesn’t take long before you realize that the brain is one of the few really immense questions. What could be more challenging and more interesting and more important than understanding the human brain? It’s got it all. It’s got computational processes, it’s got biological mechanisms, it’s got genetics; any aspect of biology you’re interested in, it’s important to brain function and it needs to be mastered before we will understand how it all works together. It’s the perfect puzzle. Once I started thinking about the issues, the challenges, the potential payoff, the brain was an obvious choice for me. I haven’t changed direction since.
Why study vision and perception and attention?
When I was in grad school at Caltech, most of the labs researching brain systems and circuits were studying vision. It wasn’t a coincidence. The visual system is a good choice for several reasons. Vision is important to humans. We rely greatly on vision, and far more of our brain is devoted to vision than to any other sense. Because we are visual animals we understand vision better in some ways than we do the other sensory modalities. It’s also relatively convenient to produce precise visual stimuli for experiments. For a few hundred dollars you can buy a visual display with millions of pixels that you can update 100 times a second. If you study the somatosensory system, there is no device you can buy that allows you to control a million points of contact on the skin, let alone with high precision. When I started in neuroscience, vision was the sensory system where a lot of progress was being made, and I fell into that progress.
What are some of your favorite discoveries that you’ve made?
In graduate school, I really liked when we stumbled on the fact that the areas in cerebral cortex that process signals coming from the eyes are arranged in a formal hierarchy. There was a lot of surprise and pleasure of seeing the order emerging from a mass of anatomical and physiological data. Similarly, I really enjoyed our experiments showing that attention to a visual stimulus primarily increases the responses of the cells in cerebral cortex that represent that stimulus, without changing the number of cells representing that stimulus. But some of my favorite experiments didn’t have simple outcomes at all; they were just fun to do. When I was first starting my own lab, we did experiments in which we would inactivate one subcortical visual pathway or another to measure how much signals in different pathway mixed when they get to cortex. The outcome was complicated, but it was always impressive to see how a tiny perturbation at one brain site could profoundly affect activity in another site many stages removed.
Not really regrets, but science has a way of humbling you. Every time we finally figure something out and reach some clarity and understanding, it almost always seems we could have gotten there much faster if we had just had the right insight or had thought about the question just a little bit differently.
What’s the one question you’d really like to know the answer to?
If you it down to the ultimate challenge in neuroscience, I’d say it’s the question of how we achieve unified action and unified experiences from hundreds of billions of individual brain cells. You feel like you’re one person. You don’t feel like you’re two cerebral hemispheres, you don’t feel like you’re 200 cortical areas, and you don’t feel like you’re 10,000 brain nuclei. But that’s what you are. In fact you’re hundreds of billions of neurons. Yet you experience being one person, with one set of goals , and one plan of action. We don’t have any solid computational or conceptual framework for how that takes place, what sort of mechanisms and computations can produce that.
What’s your least favorite thing about the brain?
It’s intimidating to face a problem as daunting as understanding the brain. It has more complexity than the rest of the body put together. We have to accept that the answers we’re seeking might be many years off. But this is a great time for neuroscience. With the new tools available, there is real promise for substantial progress in the near future.
How did you have the time to be editor-in-chief of The Journal of Neuroscience and still run a lab?
Being editor-in-chief of The Journal of Neuroscience could easily be a fulltime job. It is the largest and most cited journal in neuroscience by a wide margin. You just have to be disciplined about setting limits. I set aside a fixed block of time for journal work, and did my absolute best to pull the plug on it when the time was up. It’s reasonably straightforward to keep balance if you compartmentalize in that way.
Give one piece of advice to anyone that wants to study neuroscience.
Keep a broad perspective. What sets neuroscience apart is the range of topics it spans. It’s too easy to spiral in and focus on one particular topic. Understanding is likely to depend on embracing the breadth of neuroscience. We’re lucky to have a field that gives us an excuse to engage in so many interesting approaches and levels of organization.