Mriganka Sur Reveals the Mysteries of The Brain

Image: Justin Knight fo Forebs India

Neuroscientist Mriganka Sur

How is the brain wired? How does it code and decode information? What causes developmental disorders like autism and diseases like Alzheimer’s? These are the questions that have occupied neuroscientist Mriganka Sur over the past 30 years.

By studying the connections in the brain—and by making connections in the lab through an interdisciplinary approach—he has transformed not only his own work, but neuroscience as well.

It was in the late ’80s that Sur rose to fame when he ‘rewired’ the brain of a small animal, a ferret, at Yale University.

In that experiment he showed, for the first time, that the brain is ‘plastic’. He demonstrated how the brain changes in response to the external environment even as it continues to develop.

“That result was stunning; it beautifully combined physiology and behaviour and demonstrated his outstanding ability to hit the big questions without any fear,” says K. Vijayraghavan, director of the National Centre for Biological Sciences, who was Sur’s junior at IIT Kanpur.

After finishing at IIT, Sur moved to MIT; he wanted to combine technology and science.

At MIT, he ensured that other labs got interested in pursuing this goal. The result, in the 1990s, was the development of extensive toolkits that allowed researchers to image the brain at its barest: A single neuron.

In the following decade, Sur and his team went on to resolve this further with even higher resolution imaging. They could now see a single neuron and all its processes, even at the level of a single synapse, in the living, intact brain.

Now he’s shedding light on what happens if the brain gets “mis-wired”. The holistic understanding of plasticity has allowed Sur to bring a magnificent shift in how people study mental disorders.

In 2009, he shot into fame again when he showed that it’s the immaturity of brain circuitry that causes Rett Syndrome, a subset of autism. A disease that is on the rise, autism ranges from mild communication difficulties to severe conditions, even mental retardation, and affects about one
in 150 children anywhere in the world.

Sur represents a new class of molecular neuroscientists who, equipped with a powerful understanding of the brain, are now applying that knowledge to diseases, says Sumantra Chattarji, a neuroscientist at NCBS, who studies Fragile X, a subset of autism.

It’s strange that pharma companies never studied plasticity at its most basic. The result has been several failed trials and no breakthroughs in diseases like schizophrenia, bi-polar disorder and Alzheimer’s.

“If you now look at what these companies are doing, they are hiring some of the people in the forefront of plasticity, be it Roche or Pfizer,” says Chattarji.

Lest we start reading too much into this, Sur is quick to add that brain disorders, developmental disorders in particular, are complex; more so because children cannot be administered new drugs. His goal is to try existing drugs.

Will the problem be solved anytime soon? He doesn’t think so.

Will we make progress? You bet.
 
“We already have begun to, given that there was nothing available until now,” says Sur.

He is helping a group at the All India Institute of Medical Sciences in New Delhi to start a similar study in India where no data exists on the incidence of autism.

In January, Sur stepped down as head of the department of brain and cognitive sciences at MIT to lead a new Simon’s Center for Social Brain at MIT that became possible with a $26 million grant in December.

“We think that just as the brain has modules for vision, audition and action—which function seamlessly—there is a social module, one that mediates
different components of social interactions.” Understanding what it is and how autism makes it go wrong is a very big frontier of neuroscience, says Sur.

Sur has always sought new frontiers, even as a school boy. In Class XI at St. Joseph’s High School in Allahabad, when every student had to choose
either the math or the biology stream, he decided to do both—he was the only student in the school to do so.

Later, at IIT Kanpur, he studied electrical engineering as there wasn’t any life science course. But when he was doing his Ph.D at the University of Vanderbilt, in Nashville, Tennessee, he made sure he did his thesis research with somebody who studied the brain. “The American system allows you to do that,” he says.

The ethos of interdisciplinary work that he picked up at Vanderbilt has been carried forward through his discovery-filled career. His philosophy: All interdisciplinary work first begins in the mind.

“It’s possible to work in different subjects and link them all in the brain,” says Sur.

That belief, he says, was inculcated in him in childhood, particularly by his mathematician grandfather, who worked in the education department in Allahabad.

Over 30 years of active research, Sur has made several discoveries that link engineering, computation, imaging, molecular biology, genetics and a host of other disciplines.

For example, the first computer that he programmed was a PDP-8 with 8 kilobytes of memory at Vanderbilt, for lab work. “I was the only one around who could analyse the data using principles of engineering,” he recalls.

More than 30 years ago, Sur refused a job in India, the only one offered then, by the Tata Institute of Fundamental Research. But in the last 15 years, he has been associated with Indian science and institutions in ways that sometimes surprise him.

His association deepened in the ’90s when the government wanted to set up the National Brain Research Center (NBRC) in Haryana. The relationship was formalised in 2010 when the department of biotechnology (DBT) offered him distinguished professorship at NBRC, an institution he is keen to handhold to international standards.  

“Sur is one of those classy Indian scientists who are thriving in the US, but want to deeply engage with India now,” says M.K. Bhan, secretary, DBT.
 
Given his involvement in various Indian institutions, and his passion for active research at MIT, the pull of India could get overwhelming. “It’s fun. You never stop being Indian,” he says.