Study reveals how the brain tracks objects in motion

Catching a bouncing ball or hitting a ball with a racket requires estimating when the ball will arrive. Neuroscientists have long thought that the brain does this by calculating the speed of the moving object. However, a new study from MIT shows that the brain’s approach is more complex.

The new findings suggest that in addition to tracking speed, the brain incorporates information about the rhythmic patterns of an object’s movement: for example, how long it takes a ball to complete one bounce. In their new study, the researchers found that people make much more accurate estimates when they have access to information about both the speed of a moving object and the timing of its rhythmic patterns.

“People get really good at this when they have both types of information available,” says Mehrdad Jazayeri, the Robert A. Swanson Career Development Professor of Life Sciences and a member of MIT’s McGovern Institute for Brain Research. “It’s like having input from multiple senses. The statistical knowledge that we have about the world we’re interacting with is richer when we use multiple senses.”

Jazayeri is the senior author of the study, which appears in the Proceedings of the National Academy of Sciences the week of March 5. The paper’s lead author is MIT graduate student Chia-Jung Chang.

Objects in motion

Much of the information we process about objects moving around us comes from visual tracking of the objects. Our brains can use information about an object’s speed and the distance it has to cover to calculate when it will reach a certain point. Jazayeri, who studies how the brain keeps time, was intrigued by the fact that much of the movement we see also has a rhythmic element, such as the bouncing of a ball. 

“It occurred to us to ask, how can it be that the brain doesn’t use this information? It would seem very strange if all this richness of additional temporal structure is not part of the way we evaluate where things are around us and how things are going to happen,” Jazayeri says.

There are many other sensory processing tasks for which the brain uses multiple sources of input. For example, to interpret language, we use both the sound we hear and the movement of the speaker’s lips, if we can see them. When we touch an object, we estimate its size based on both what we see and what we feel with our fingers.

In the case of perceiving object motion, teasing out the role of rhythmic timing, as opposed to speed, can be difficult. “I can ask someone to do a task, but then how do I know if they’re using speed or they’re using time, if both of them are always available?” Jazayeri says.

To overcome that, the researchers devised a task in which they could control how much timing information was available. They measured performance in human volunteers as they performed the task.

During the task, the study participants watched a ball as it moved in a straight line. After traveling some distance, the ball went behind an obstacle, so the participants could no longer see it. They were asked to press a button at the time when they expected the ball to reappear.

Performance varied greatly depending on how much of the ball’s path was visible before it went behind the obstacle. If the participants saw the ball travel a very short distance before disappearing, they did not do well. As the distance before disappearance became longer, they were better able to calculate the ball’s speed, so their performance improved but eventually plateaued.

After that plateau, there was a significant jump in performance when the distance before disappearance grew until it was exactly the same as the width of the obstacle. In that case, when the path seen before disappearance was equal to the path the ball traveled behind the obstacle, the participants improved dramatically, because they knew that the time spent behind the obstacle would be the same as the time it took to reach the obstacle.

When the distance traveled to reach the obstacle became longer than the width of the obstacle, performance dropped again.

“It’s so important to have this extra information available, and when we have it, we use it,” Jazayeri says. “Temporal structure is so important that when you lose it, even at the expense of getting better visual information, people’s performance gets worse.”

Integrating information

The researchers also tested several computer models of how the brain performs this task, and found that the only model that could accurately replicate their experimental results was one in which the brain measures speed and timing in two different areas and then combines them.

Previous studies suggest that the brain performs timing estimates in premotor areas of the cortex, which plays a role in planning movement; speed, which usually requires visual input, is calculated in visual cortex. These inputs are likely combined in parts of the brain responsible for spatial attention and tracking objects in space, which occurs in the parietal cortex, Jazayeri says.

In future studies, Jazayeri hopes to measure brain activity in animals trained to perform the same task that human subjects did in this study. This could shed further light on where this processing takes place and could also reveal what happens in the brain when it makes incorrect estimates.

The research was funded by the McGovern Institute for Brain Research.

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Outstanding MIT students of French explore "Paris et la rue"

Think of Paris, and images materialize of sublime art and cosmopolitan sophistication. “We all romanticize the culture, and it’s fine to do that,” says Bruno Perreau, the Cynthia L. Reed Professor and associate professor of French studies. “But we also need to add different layers and rethink the connection between myth and reality,” he says.

In search of this connection, Perreau brought seven students to Paris for the annual January Scholars in France program, offered during MIT’s independent activities period. Chosen through a competitive process, the January Scholars students are among the best in MIT's French studies and language program, and spoke exclusively in French during their stay in Paris. For their travels, the students receive airfare, lodging in a youth hostel, transportation and meals, courtesy of the French Initiatives Endowment Fund.

Led by expert local guides, the group pursued a theme, “Paris et la rue” (Paris and the street), which took them beyond the usual tourist spots and into lesser-known residential and business neighborhoods. During walking tours, the students peeled back layers of history, learned about city planning past and present, and glimpsed behind-the-scenes views of workaday, contemporary Paris. They explored the history of street revolutions in 18th and 19th century Paris, issues of public transportation, new architectural projects, and street art.  It was an itinerary that encouraged students “to encounter aspects of Parisian life they couldn’t have imagined,” says Perreau.
 
Another side of Paris

“We got to learn about things like the design process behind the trash cans and the type of barricades built by revolting Parisians from the 17th straight through to the 20th century,” recounts Anelise Newman, a junior majoring in electrical engineering and computer science.

“We saw parts of the city, like the business sector and the atelier and works of Raymond Moretti … and most importantly, we got to interact with Parisians not as tourists, but as students who were genuinely interested in learning the culture and mastering the language,” says Newman, who also wrote a blog post for MIT Admissions about the trip.

Unexpected episodes enlivened and enriched their daily tours. In a visit to the 13th arrondissement, which began in the 19th century as a factory district and is now home to public housing and a vibrant Asian population, the group took in the many giant murals plastered on the sides of buildings.

“We triggered reactions from locals, who argued with us about their favorite or most hated pieces of public art,” recalls Perreau. “Students were surprised about how attached people were to their personal visions of the city.”

At La Defense, a sprawling business district dotted by high-rises with a subterranean infrastructure for highways, parking, and the Metro, the group found unexpected adventure. The city’s chief archivist and a security detail opened a series of locked doors, and descending a stairway with flashlights, revealed a hidden area.

“We were taken underground to see the atelier and works of Raymond Moretti, a sculptor who passed away 13 years ago,” says Rebecca Grekin, a chemical engineering major. “We felt so privileged to be invited into a place that was normally off limits.”

Perreau, who likened the concealed cavern to “a cathedral or grotto,” was astonished to find himself face to face with a gigantic sculpture nicknamed “the monster” because of the roar from nearby subway trains.

“We had this feeling of being explorers,” he says. “I saw another side of Paris that had been concealed from me, even after having lived there for years.”

Pulling back the curtain

Even at some of the more glittery Parisian venues, MIT travelers were able to pull back the curtain and gain unusual perspectives. During a private tour of the Palais Garnier, home to the Paris Opera Ballet, the troupe’s star dancer, Germain Louvet, showed them spaces normally inaccessible to the public: a fake ceiling behind which gentleman from high society once chose dancers with whom to consort, and in the basement, a tank full of water intended in the 19th century to douse fires, but now full of koi fish.

“I grew up dancing in Accra, Ghana and was obsessed by the Paris ballet,” says Sefa Yakpo, a senior double majoring in management science and French. “So first I couldn’t believe I was standing backstage with the étoile (star), and later I was literally speechless when we went out to a café with him and learned about his life,” she says.

To top off this prized experience, the group attended a performance the following night of the ballet Don Quixote at the Bastille Opera, where they witnessed a once-in-a lifetime crowning of a female star dancer.

Yakpo, who had worked in Paris the previous summer for a consultant firm, felt as if she was seeing the city for the first time. “I walked on very familiar streets, but peeling off layers of history and understanding the politics and culture of these places showed me how a city can have many different faces,” she says.

One of Perreau’s goals was to “shift students’ perceptions of Paris and France, to build new understanding” while having fun together and enjoying the many riches the city has to offer. “There is something about pleasure at the heart of the program,” he says.

Perreau may have succeeded in ways he didn’t anticipate. Grekin returned to Boston determined to continue the French experience. “I am going to keep practicing the language with a friend I made on the trip, and start going to the Boston Symphony Orchestra,” she says.

Safpo found the Paris sojourn a balm for the soul. “At MIT, where at times facts and solving problems make life seem clinical, you can forget to embrace something just because it’s beautiful,” she says. “Music, dance, art — things that touch us — are like magic, and Paris reminded me of the importance of that.”

Story prepared by SHASS Communications
Editorial and Design Director: Emily Hiestand
Writer: Leda Zimmerman

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Insulator or superconductor? Physicists find graphene is both

It’s hard to believe that a single material can be described by as many superlatives as graphene can. Since its discovery in 2004, scientists have found that the lacy, honeycomb-like sheet of carbon atoms — essentially the most microscopic shaving of pencil lead you can imagine — is not just the thinnest material known in the world, but also incredibly light and flexible, hundreds of times stronger than steel, and more electrically conductive than copper.

Now physicists at MIT and Harvard University have found the wonder material can exhibit even more curious electronic properties. In two papers published today in Nature, the team reports it can tune graphene to behave at two electrical extremes: as an insulator, in which electrons are completely blocked from flowing; and as a superconductor, in which electrical current can stream through without resistance.

Researchers in the past, including this team, have been able to synthesize graphene superconductors by placing the material in contact with other superconducting metals — an arrangement that allows graphene to inherit some superconducting behaviors. This time around, the team found a way to make graphene superconduct on its own, demonstrating that superconductivity can be an intrinsic quality in the purely carbon-based material.

The physicists accomplished this by creating a “superlattice” of two graphene sheets stacked together — not precisely on top of each other, but rotated ever so slightly, at a “magic angle” of 1.1 degrees. As a result, the overlaying, hexagonal honeycomb pattern is offset slightly, creating a precise moiré configuration that is predicted to induce strange, “strongly correlated interactions” between the electrons in the graphene sheets. In any other stacked configuration, graphene prefers to remain distinct, interacting very little, electronically or otherwise, with its neighboring layers.

The team, led by Pablo Jarillo-Herrero, an associate professor of physics at MIT, found that when rotated at the magic angle, the two sheets of graphene exhibit nonconducting behavior, similar to an exotic class of materials known as Mott insulators. When the researchers then applied voltage, adding small amounts of electrons to the graphene superlattice, they found that, at a certain level, the electrons broke out of the initial insulating state and flowed without resistance, as if through a superconductor.

“We can now use graphene as a new platform for investigating unconventional superconductivity,” Jarillo-Herrero says. “One can also imagine making a superconducting transistor out of graphene, which you can switch on and off, from superconducting to insulating. That opens many possibilities for quantum devices.”

A 30-year gap

A material’s ability to conduct electricity is normally represented in terms of energy bands. A single band represents a range of energies that a material’s electrons can have. There is an energy gap between bands, and when one band is filled, an electron must embody extra energy to overcome this gap, in order to occupy the next empty band.

A material is considered an insulator if the last occupied energy band is completely filled with electrons. Electrical conductors such as metals, on the other hand, exhibit partially filled energy bands, with empty energy states which the electrons can fill to freely move.

Mott insulators, however, are a class of materials that appear from their band structure to conduct electricity, but when measured, they behave as insulators. Specifically, their energy bands are half-filled, but because of strong electrostatic interactions between electrons (such as charges of equal sign repelling each other), the material does not conduct electricity. The half-filled band essentially splits into two miniature, almost-flat bands, with electrons completely occupying one band and leaving the other empty, and hence behaving as an insulator.

“This means all the electrons are blocked, so it’s an insulator because of this strong repulsion between the electrons, so nothing can flow,” Jarillo-Herrero explains. “Why are Mott insulators important? It turns out the parent compound of most high-temperature superconductors is a Mott insulator.”

In other words, scientists have found ways to manipulate the electronic properties of Mott insulators to turn them into superconductors, at relatively high temperatures of about 100 Kelvin. To do this, they chemically “dope” the material with oxygen, the atoms of which attract electrons out of the Mott insulator, leaving more room for remaining electrons to flow. When enough oxygen is added, the insulator morphs into a superconductor. How exactly this transition occurs, Jarillo-Herrero says, has been a 30-year mystery.

“This is a problem that is 30 years and counting, unsolved,” Jarillo-Herrero says. “These high-temperature superconductors have been studied to death, and they have many interesting behaviors. But we don’t know how to explain them.”

A precise rotation

Jarillo-Herrero and his colleagues looked for a simpler platform to study such unconventional physics. In studying the electronic properties in graphene, the team began to play around with simple stacks of graphene sheets. The researchers created two-sheet superlattices by first exfoliating a single flake of graphene from graphite, then carefully picking up half the flake with a glass slide coated with a sticky polymer and an insulating material of boron nitride.

They then rotated the glass slide very slightly and picked up the second half of the graphene flake, adhering it to the first half. In this way, they created a superlattice with an offset pattern that is distinct from graphene’s original honeycomb lattice.

The team repeated this experiment, creating several “devices,” or graphene superlattices, with various angles of rotation, between 0 and 3 degrees. They attached electrodes to each device and measured an electrical current passing through, then plotted the device’s resistance, given the amount of the original current that passed through.

“If you are off in your rotation angle by 0.2 degrees, all the physics is gone,” Jarillo-Herrero says. “No superconductivity or Mott insulator appears. So you have to be very precise with the alignment angle.”

At 1.1 degrees — a rotation that has been predicted to be a “magic angle” — the researchers found the graphene superlattice electronically resembled a flat band structure, similar to a Mott insulator, in which all electrons carry the same energy regardless of their momentum.

“Imagine the momentum for a car is mass times velocity,” Jarillo-Herrero says. “If you’re driving at 30 miles per hour, you have a certain amount of kinetic energy. If you drive at 60 miles per hour, you have much higher energy, and if you crash, you could deform a much bigger object. This thing is saying, no matter if you go 30 or 60 or 100 miles per hour, they would all have the same energy.”

“Current for free”

For electrons, this means that, even if they are occupying a half-filled energy band, one electron does not have any more energy than any other electron, to enable it to move around in that band. Therefore, even though such a half-filled band structure should act like a conductor, it instead behaves as an insulator — and more precisely, a Mott insulator.

This gave the team an idea: What if they could add electrons to these Mott-like superlattices, similar to how scientists doped Mott insulators with oxygen to turn them into superconductors? Would graphene assume superconducting qualities in turn?

To find out, they applied a small gate voltage to the “magic-angle graphene superlattice,” adding small amounts of electrons to the structure. As a result, individual electrons bound together with other electrons in graphene, allowing them to flow where before they could not. Throughout, the researchers continued to measure the electrical resistance of the material, and found that when they added a certain, small amount of electrons, the electrical current flowed without dissipating energy — just like a superconductor.

“You can flow current for free, no energy wasted, and this is showing graphene can be a superconductor,” Jarillo-Herrero says.

Perhaps more importantly, he says the researchers are able to tune graphene to behave as an insulator or a superconductor, and any phase in between, exhibiting all these diverse properties in one single device. This is in contrast to other methods, in which scientists have had to grow and manipulate hundreds of individual crystals, each of which can be made to behave in just one electronic phase.

“Usually, you have to grow different classes of materials to explore each phase,” Jarillo-Herrero says. “We’re doing this in-situ, in one shot, in a purely carbon device. We can explore all those physics in one device electrically, rather than having to make hundreds of devices. It couldn’t get any simpler.”

This research was supported in part by the Gordon and Betty Moore Foundation and ther National Science Foundation.

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Viral tool traces long-term neuron activity

For the past decade, neuroscientists have been using a modified version of the rabies virus to label neurons and trace the connections between them. Although this technique has proven very useful, it has one major drawback: The virus is toxic to cells and can’t be used for studies longer than about two weeks.

Researchers at MIT and the Allen Institute for Brain Science have now developed a new version of this virus that stops replicating once it infects a cell, allowing it to deliver its genetic cargo without harming the cell. Using this technique, scientists should be able to study the infected neurons for several months, enabling longer-term studies of neuron functions and connections.

“With the first-generation vectors, the virus is replicating like crazy in the infected neurons, and that’s not good for them,” says Ian Wickersham, a principal research scientist at MIT’s McGovern Institute for Brain Research and the senior author of the new study. “With the second generation, infected cells look normal and act normal for at least four months — which was as long as we tracked them — and probably for the lifetime of the animal.”

Soumya Chatterjee of the Allen Institute is the lead author of the paper, which appears in the March 5 issue of Nature Neuroscience.

Using two-photon microscopy, researchers can image fluorescent cells in the brains of live mice. These two images were taken of the same group of neurons in visual cortex at nine days (left) and 22 days (right) following injection of a first-generation rabies viral vector encoding a red fluorescent protein. The vast majority of infected neurons visible at the earlier time point are gone by the later imaging session.

These two images show the same group of neurons in visual cortex at four weeks (left) and eight weeks (right) following injection of a second-generation rabies viral vector encoding Cre recombinase, which causes cells in these transgenic mice to express a red fluorescent protein. All neurons visible at the earlier time point are still present at the later one.

Viral tracing

Rabies viruses are well-suited for tracing neural connections because they have evolved to spread from neuron to neuron through junctions known as synapses. The viruses can also spread from the terminals of axons back to the cell body of the same neuron. Neuroscientists can engineer the viruses to carry genes for fluorescent proteins, which are useful for imaging, or for light-sensitive proteins that can be used to manipulate neuron activity.

In 2007, Wickersham demonstrated that a modified version of the rabies virus could be used to trace synapses between only directly connected neurons. Before that, researchers had been using the rabies virus for similar studies, but they were unable to keep it from spreading throughout the entire brain.

By deleting one of the virus’ five genes, which codes for a glycoprotein normally found on the surface of infected cells, Wickersham was able to create a version that can only spread to neurons in direct contact with the initially infected cell. This 2007 modification enabled scientists to perform “monosynaptic tracing,” a technique that allows them to identify connections between the infected neuron and any neuron that provides input to it.

This first generation of the modified rabies virus is also used for a related technique known as retrograde targeting, in which the virus can be injected into a cluster of axon terminals and then travel back to the cell bodies of those axons. This can help researchers discover the location of neurons that send impulses to the site of the virus injection.

Researchers at MIT have used retrograde targeting to identify populations of neurons of the basolateral amygdala that project to either the nucleus accumbens or the central medial amygdala. In that type of study, researchers can deliver optogenetic proteins that allow them to manipulate the activity of each population of cells. By selectively stimulating or shutting off these two separate cell populations, researchers can determine their functions.

Reduced toxicity

To create the second-generation version of this viral tool, Wickersham and his colleagues deleted the gene for the polymerase enzyme, which is necessary for transcribing viral genes. Without this gene, the virus becomes less harmful and infected cells can survive much longer. In the new study, the researchers found that neurons were still functioning normally for up to four months after infection.

“The second-generation virus enters a cell with its own few copies of the polymerase protein and is able to start transcribing its genes, including the transgene that we put into it. But then because it’s not able to make more copies of the polymerase, it doesn’t have this exponential takeover of the cell, and in practice it seems to be totally nontoxic,” Wickersham says.

The lack of polymerase also greatly reduces the expression of whichever gene the researchers engineer into the virus, so they need to employ a little extra genetic trickery to achieve their desired outcome. Instead of having the virus deliver a gene for a fluorescent or optogenetic protein, they engineer it to deliver a gene for an enzyme called Cre recombinase, which can delete target DNA sequences in the host cell’s genome.

This virus can then be used to study neurons in mice whose genomes have been engineered to include a gene that is turned on when the recombinase cuts out a small segment of DNA. Only a small amount of recombinase enzyme is needed to turn on the target gene, which could code for a fluorescent protein or another type of labeling molecule. The second-generation viruses can also work in regular mice if the researchers simultaneously inject another virus carrying a recombinase-activated gene for a fluorescent protein.

The new paper shows that the second-generation virus works well for retrograde labeling, not tracing synapses between cells, but the researchers have also now begun using it for monosynaptic tracing.

The research was funded by the National Institute of Mental Health, the National Institute on Aging, and the National Eye Institute.

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Edward Boyden named inaugural Y. Eva Tan Professor in Neurotechnology

Edward S. Boyden, a member of MIT’s McGovern Institute for Brain Research and the Media Lab, and an associate professor of brain and cognitive sciences and biological engineering at MIT, has been appointed the inaugural Y. Eva Tan Professor in Neurotechnology. The new professorship has been established at the McGovern Institute by K. Lisa Yang in honor of her daughter Y. Eva Tan.

“We are thrilled Lisa has made a generous investment in neurotechnology and the McGovern Institute by creating this new chair,” says Robert Desimone, director of the McGovern Institute. “Ed’s body of work has already transformed neuroscience and biomedicine, and this chair will help his team to further develop revolutionary tools that will have a profound impact on research worldwide.”

In 2017, Yang co-founded the Hock E. Tan and K. Lisa Yang Center for Autism Research at the McGovern Institute. The center catalyzes interdisciplinary and cutting-edge research into the genetic, biological, and brain bases of autism spectrum disorders. In late 2017, Yang grew the center with the establishment of the endowed J. Douglas Tan Postdoctoral Research Fund, which supports talented postdocs in the lab of Poitras Professor of Neuroscience Guoping Feng.

“I am excited to further expand the Hock E. Tan and K. Lisa Yang Center for Autism Research and to support Ed and his team’s critical work,” says Yang. “Novel technology is the driving force behind much-needed breakthroughs in brain research — not just for individuals with autism, but for those living with all brain disorders. My daughter Eva and I are greatly pleased to recognize Ed’s talent and to contribute toward his future successes.”

Yang’s daughter agrees. “I’m so pleased this professorship will have a significant and lasting impact on MIT’s pioneering work in neurotechnology,” says Tan. “My family and I have always believed that advances in technology are what make all scientific progress possible, and I’m overjoyed that we can help enable amazing discoveries in the Boyden Lab through Ed’s appointment to this chair.”

Boyden has pioneered the development of many transformative technologies that image, record, and manipulate complex systems, including optogenetics, expansion microscopy, and robotic patch clamping. He has received numerous awards for this work, including the Breakthrough Prize in Life Sciences (2016), the BBVA Foundation Frontiers of Knowledge Award (2015), the Carnegie Prize in Mind and Body Sciences (2015), the Grete Lundbeck European Brain Prize (2013), and the Perl-UNC Neuroscience prize (2011). Boyden is an elected member of the American Academy of Arts and Sciences and the National Academy of Inventors.

“I deeply appreciate the honor that comes with being named the first Y. Eva Tan Professor in Neurotechnology,” says Boyden. “This is a tremendous recognition of not only my team’s work, but the groundbreaking impact of the neurotechnology field.”

Boyden joined MIT in 2007 as an assistant professor at the Media Lab, and later was appointed as a joint professor in the departments of Brain and Cognitive Sciences and Biological Engineering and an investigator in the McGovern Institute. In 2011, he was named the Benesse Career Development Professor, and in 2013 he was awarded the AT&T Career Development Professorship. Seven years after arriving at MIT, he was awarded tenure. Boyden earned his BS and MEng from MIT in 1999 and his PhD in Neuroscience from Stanford University in 2005.

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Four professors named 2018 MacVicar Fellows

This Friday, the MIT community will gather to celebrate exceptional undergraduate teaching and discuss inclusive classroom practices and strategies as part of the 26th annual MacVicar Day.

The 2018 MacVicar Faculty fellows are: David Autor, the Ford Professor of Economics and associate head of the Department of Economics; Christopher Capozzola, an associate professor of history; Shankar Raman, a professor of literature; and Merritt Roe Smith, the
Leverett and William Cutten Professor of the History of Technology in the Department of History and the Program in Science, Technology, and Society (STS).

MacVicar Day is named after the late professor Margaret MacVicar, founder of MIT’s renowned Undergraduate Research Opportunities Program (UROP) and the first dean for undergraduate education. She revolutionized the undergraduate experience by refusing to accept the status quo. With a fierce belief in her students’ ability, she expanded research opportunities, revised academic requirements, and fostered a welcoming and innovative community. The MacVicar Faculty Fellows Program recognizes professors who continue her work as a champion of teaching and advising, and who engage with students to advance the mission of the Institute.

Fellows are selected through an annual merit-based nomination process. An advisory committee — comprised of the vice chancellor, faculty from each of the five schools, and current undergraduate students — review the nominations and recommend candidates to the provost. Each fellow receives $10,000 per year, over a 10-year term, for educational activities, research, travel, and other scholarly expenses.

This year’s MacVicar Day symposium is titled “Inclusive Pedagogies: Building a Vibrant Community of Learners at MIT.” Vice Chancellor Ian A. Waitz will host the event. A panel of MIT faculty — including Catherine Drennan, Eric Klopfer, Katrina LaCurts, Christine Ortiz, and Meredith Thompson — will share the ways in which they have cultivated inclusive learning environments. A special introduction will honor former president Paul Gray’s contributions to undergraduate education and, in particular, his commitment to making MIT more diverse and representative.

The symposium will take place on Friday, March 9, from 2 to 4 p.m. in Room 6-120. A reception will follow in the Chipman Room (Room 6-104). The entire MIT community is welcome.

David Autor

Autor received a bachelor's degree in psychology from Tufts University and a master's degree and PhD in public policy from Harvard University’s Kennedy School of Government. He joined the MIT community in 1999.

Autor is a co-director of the MIT School Effectiveness and Inequality Initiative (SEII), which studies the economics of education and the connections between human capital and the American income distribution. Recent subjects taught include Labor Economics and Microeconomic Theory and Public Policy.

“I’m utterly thrilled to be selected as a MacVicar fellow,” Autor says. “MIT undergraduates are simply the best students a professor could ever hope to encounter. They’re incredibly capable, brutally hardworking, and, most of all, endlessly intellectually inquisitive. Some of the best questions I’ve ever encountered at MIT have come from my undergraduates. It’s an honor to be in a classroom with them.”

Autor also reflected on his own experience as a student and how it has shaped his teaching: “I didn’t study economics at all as an undergraduate. I discovered it by accident from an inspiring professor who enabled students to grasp the value of economics. Likewise, I hope to convey to MIT students why economics is such a powerful lens for understanding the world, how economics research is done, and how researchers, policymakers, and engaged citizens use economics to make astute decisions.”

Advising was highlighted as one of Autor’s greatest strengths by his nominators. “At my own crossroads when I deliberated between different careers, Prof. Autor cared to find an array of values that motivated me and helped me appreciate how they harmonize. I believe that building these kinds of bridges is at the heart of maintaining diversity and being an agent for it,” one student wrote.

“David is one of the most sought-after undergraduate research supervisors, and he is particularly well-known for involving his undergraduate students in research projects that provide them with an introduction to cutting-edge research,” says Nancy Rose, the Charles P. Kindleberger Professor of Applied Economics and head of the Department of Economics.

The creation of a new major, called computer science, economics and data science (Course 6-14), in fall 2017, was due in large part to Autor’s resolve. “Had it not been for the excitement, engagement, vision, and steady hand of David, this major would not have happened,” wrote Konstantinos Daskalakis, an associate professor of electrical engineering and computer science.

Christopher Capozzola

Capozzola is an associate professor of history, focusing on the political and cultural history of the United States from the late-19th century to the present. He received a bachelor's degree from Harvard College and a master's degree, MPhil, and PhD from Columbia University. In 2002, he joined the MIT faculty as an assistant professor. He was promoted to Lister Brother Career Development Associate Professor of History in 2006, and then to associate professor with tenure in 2009. From 2011 to 2012, he served as the acting associate dean of the School of Humanities, Arts, and Social Sciences.

Capozzola says that the MacVicar fellowship is, first and foremost, “an award that honors MIT undergraduates, who are such an exciting challenge to teach. They’re hardworking, no-nonsense, and unimaginably curious. They are willing to hear about the history of time zones or neckties and how it relates to American history; ready to wander around the Lower East Side in the rain or the Salem waterfront in the heat; and always eager to challenge their own assumptions … and mine, too.”

“I’ve had the good fortune to share the classroom with gifted teaching assistants, writing instructors, and fellow professors, and I share this award with them. Along the way, many offices at MIT have supported teaching experiments, from first-year focus subjects to MOOCs. It has meant a lot to me to teach at a place that truly values trying something new in the classroom every day.”

Examples of Capozzola’s innovative and hands-on approach to teaching filled the nomination materials. “Every class was an adventure,” one student wrote. “He pushed us to think outside the historical narratives we had been given in previous history classes or popular culture, and to develop our own viewpoints on the events we studied based on the facts and stories from primary sources.”

Capozzola’s background in museum and public history informs the importance he places on primary sources in his lessons. He enlists a wide range of contemporaneous documents — such as articles, cartoons, short films, letters, and novels from the era — in his teaching. When he taught a seminar on the history of the immigrant experience, he arranged for students to travel to New York City, where they walked through prominent immigrant neighborhoods, ate foods from other cultures, and visited historical sites.

Craig Steven Wilder, the Barton L. Weller Professor of History wrote: “[Capozzola’s] commitment to education and learning does not begin and end at the classroom door; rather, he brings students to spaces where they get to see and reinterpret the past, and where they discover how history informs and encompasses their lives.”

Students agreed. “Professor Capozzola,” one said, “challenged [us] to push beyond our preconceived notions and assumptions, and to engage with historical evidence with an open mind. … His guidance led to a fascinating and thought-provoking discussion of ethics, responsibility, statehood, and citizenship — one that profoundly shaped my future academic work and thought.”

Shankar Raman

Raman is a professor of literature. His research ranges from Renaissance and late-Medieval literature and culture to post-colonialism and literary theory. After receiving bachelor's degrees in electrical engineering and architecture at MIT and a master's degree in electrical engineering from the University of California at Berkeley, Raman changed fields and received a master's and PhD in English literature from Stanford University. He began teaching at MIT in 1995, gained tenure in 2002, and received full professor status in 2012.

Raman’s unconventional path has proven particularly beneficial to his students. “One of the most unique and helpful aspects of Prof. Raman’s advising,” one former student wrote, “was his ability to leverage his own unique life trajectory, which enables him to connect with MIT students on their own technically-minded terms better than most.”

Colleagues praise Raman’s “pedagogically insightful, generously collective” personality. Head of the literature section, Mary C. Fuller, says, “Shankar transmits to students his own appetite for thinking beyond the classroom.”

This sentiment was echoed in many of the student nominations. “It’s hard not to be intoxicated by the kind of intellectual energy Prof. Raman fosters in his classes. It’s why I chose to take another class with him, why I recommend his classes to my friends, and why he is one of my favorite professors at the Institute,” one wrote.

“His capacity for explaining abstruse philosophy is unrivaled, and his excitement about ideas is infectious. Twelve years later, I still have and refer to the handouts from [his literary theory] course,” another wrote.

As curriculum committee chair, Raman was influential in the creation of popular six-unit literature subjects called samplings, which focus on reading and discussion. “The samplings subjects are now a permanent fixture in the literature curriculum and have brought in many students who may not otherwise have taken a literature class at MIT. That these subjects exist at all is due to Shankar’s vision and initiative,” says Noel Jackson, an associate professor of literature.

Raman was humbled upon learning that he would be a MacVicar fellow. “My first reaction was one of gratitude towards friends and colleagues in my department and at MIT. I am fortunate to have a number of colleagues who have functioned as pedagogical models over the years, leading me to think more deeply about what works in the classroom. I am grateful to those who got me interested in educational policy at MIT, getting me involved in pedagogical issues whose impact extends beyond the classroom. I am still a little surprised that I was chosen, but am honored by the award, and look forward to contributing further to teaching here at MIT in years to come.”

Merritt Roe Smith

Smith completed his undergraduate studies in history at Georgetown University, and then went on to receive a master's degree and PhD in history from Pennsylvania State University. During his incredible 40-year tenure at MIT, Smith has served as STS program director and housemaster of Burton-Conner House. He teaches a range of subjects in STS and history, including STS.026 (History of Manufacturing in America) and 21H.205 (Civil War and Modern America).

Smith is a “model of best practices” who is beloved for his “practical compassion” and the way he “treats everyone with dignity and generosity,” according to his nominators. He has a loyal following of students who describe themselves as “concentrating in Roe.”

Smith emboldens his students to come to their own conclusions by asking questions and listening to others. As one student explained: “When Prof. Smith gives a lecture, he doesn’t simply teach. He makes sure that each and every student in the class is empowered to state their unique opinion. He challenges our existing preconceptions and compels us to see history from different perspectives.”

Deborah Douglas, director of collections at the MIT Museum, witnessed Smith’s exemplary teaching firsthand when she co-taught STS.050 (The History of MIT) with him. As students introduced themselves on the first day of class, at least a third of them said that they were there expressly because of Smith. “Every teacher has a few students who become quite devoted,” Douglas says, “but I had never seen quite so many before.”

Smith credits his role as housemaster as a major factor in his success. “I’m very honored to be named a MacVicar Faculty fellow. Undergraduate education means a great deal to me. I feel optimistic about the future because I have met and interacted with so many remarkable young adults.”

“As a housemaster, I learned how undergraduates thought about their classes and prioritized things, and I learned to better appreciate student schedules and adjust my teaching commitments. I tried to become more flexible in my demands while maintaining high academic standards and, as a result, saw the work my students submitted improve significantly. I’ve learned as much from these students as they’ve learned from me.”

Rosalind Williams, the Bern Dibner Professor of the History of Science and Technology says of her colleague: “He shows his students how to learn, how to listen, how to discuss, and why it all matters. One of the students told me that Professor Smith was not trying to be a star performer but a conductor, showing them how to create a symphony of ideas.”

de MIT News http://ift.tt/2thw5vd

Human factors engineering class tackles design for aging

Human Factors Engineering: Designing for the Human, a class offered during MIT’s 2018 Independent Activities Period, challenged teams to redesign everyday things for older adults. In a garage-style classroom at MIT’s International Design Center (IDC), teams alternated between lectures by experts in human-centered design and human factors, and hackathon-style brainstorming and building in IDC’s maker spaces.

Judges of the final projects delivered a tie: team Liftoff’s portable, pneumatic, accessible car seat and team SafeSlice’s 3-D food-stabilizing cutting board. Other projects included a voice-activated virtual cooking assistant, an app matching skilled older adults with young adults eager to learn, and a home dashboard shared with caregivers and medical experts.

Ben Sawyer, AgeLab researcher and instructor, explains the popularity of the class, “Reviews told us repeatedly that students knew employers wanted this skill set, but they had not had much exposure,” says Sawyer. “Human factors gives engineers a recognized tool set through which to understand the population their work will help.” SafeSlice’s Evan Brown agrees: “These things apply no matter what you’re designing.”

Liftoff’s accessible, portable, USB-chargeable seat was inspired by the team’s experiences with their own grandparents. “The first ... problem that came into my mind was standing up,” says Amy Umaretiya, a graduate student with MIT’s Future of Nuclear Energy group. “The hardest thing ... is developing the idea. When it came together ... we said ‘Yes! We found it!’”

Liftoff’s USB-chargeable seat allows passengers to easily rotate and boost themselves out of a vehicle. The group consulted grandparents throughout the design process and used task analysis, a technique they learned in the class lectures. “Actually acting it out helps, because you realize you’re doing movements you would never have thought of,” says Dustin Weigl, a graduate student with MIT’s Mobility of the Future group.

SafeSlice’s stabilizing cutting board, with a toy-inspired design, went through many iterations. “We started off with a pair of scissors, found there was a lot ... already on the market, and then shifted” says William Li. “We tried to make it as intuitive as possible,” says Hannah Hoffmann, graduate student at MIT’s Plasma Science and Fusion Center. Brown thought the human factors and human-centered design concepts from the class would be useful in industry engineering settings: “There’s certainly lots of things that I’ve worked on where you’re scratching you’re head,” says Brown. “Why did someone put this here?”

More information on the teams and class, as well as the winning redesigns can be found on the class website.

de MIT News http://ift.tt/2FQ3r7b