Distinctive brain pattern helps habits form

Our daily lives include hundreds of routine habits. Brushing our teeth, driving to work, or putting away the dishes are just a few of the tasks that our brains have automated to the point that we hardly need to think about them.

Although we may think of each of these routines as a single task, they are usually made up of many smaller actions, such as picking up our toothbrush, squeezing toothpaste onto it, and then lifting the brush to our mouth. This process of grouping behaviors together into a single routine is known as “chunking,” but little is known about how the brain groups these behaviors together.

MIT neuroscientists have now found that certain neurons in the brain are responsible for marking the beginning and end of these chunked units of behavior. These neurons, located in a brain region highly involved in habit formation, fire at the outset of a learned routine, go quiet while it is carried out, then fire again once the routine has ended.

This task-bracketing appears to be important for initiating a routine and then notifying the brain once it is complete, says Ann Graybiel, an Institute Professor at MIT, a member of the McGovern Institute for Brain Research, and the senior author of the study.

Nuné Martiros, a recent MIT PhD recipient who is now a postdoc at Harvard University, is the lead author of the paper, which appears in the Feb. 8 issue of Current Biology. Alexandra Burgess, a recent MIT graduate and technical associate at the McGovern Institute, is also an author of the paper.

Routine activation

Graybiel has previously shown that a part of the brain called the striatum, which is found in the basal ganglia, plays a major role in habit formation. Several years ago, she and her group found that neuron firing patterns in the striatum change as animals learn a new habit, such as turning to the right or left in a maze upon hearing a certain tone.

When the animal is just starting to learn the maze, these neurons fire continuously throughout the task. However, as the animal becomes better at making the correct turn to receive a reward, the firing becomes clustered at the very beginning of the task and at the very end. Once these patterns form, it becomes extremely difficult to break the habit.

However, these previous studies did not rule out other explanations for the pattern, including the possibility that it might be related to the motor commands required for the maze-running behavior. In the new study, Martiros and Graybiel set out to determine whether this firing pattern could be conclusively linked with the chunking of habitual behavior.

The researchers trained rats to press two levers in a particular sequence, for example, 1-2-2 or 2-1-2. The rats had to figure out what the correct sequence was, and if they did, they received a chocolate milk reward. It took several weeks for them to learn the task, and as they became more accurate, the researchers saw the same beginning-and-end firing patterns develop in the striatum that they had seen in their previous habit studies.

Because each rat learned a different sequence, the researchers could rule out the possibility that the patterns correspond to the motor input required to preform a particular series of movements. This offers strong evidence that the firing pattern corresponds specifically to the initiation and termination of a learned routine, the researchers say.

“I think this more or less proves that the development of bracketing patterns serves to package up a behavior that the brain — and the animals — consider valuable and worth keeping in their repertoire. It really is a high-level signal that helps to release that habit, and we think the end signal says the routine has been done,” Graybiel says.

Distinctive patterns

The researchers also discovered a distinct pattern in a set of inhibitory neurons in the striatum. Activity in these neurons, known as interneurons, displayed a strong inverse relationship with the activity of the excitatory neurons that produce the bracketing pattern.

“The interneurons were activated during the time when the rats were in the middle of performing the learned sequence, and could possibly be preventing the principal neurons from initiating another routine until the current one was finished. The discovery of this opposite activity by the interneurons also gets us one step closer to understanding how brain circuits can actually produce this pattern of activity,” Martiros says.

Graybiel’s lab is now investigating further how the interaction between these two groups of neurons helps to encode habitual behavior in the striatum.

The research was funded by the National Institutes of Health/National Institute of Mental Health, the Office of Naval Research, and a McGovern Institute Mark Gorenberg Fellowship.

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Study reveals molecular mechanisms of memory formation

MIT neuroscientists have uncovered a cellular pathway that allows specific synapses to become stronger during memory formation. The findings provide the first glimpse of the molecular mechanism by which long-term memories are encoded in a region of the hippocampus called CA3.

The researchers found that a protein called Npas4, previously identified as a master controller of gene expression triggered by neuronal activity, controls the strength of connections between neurons in the CA3 and those in another part of the hippocampus called the dentate gyrus. Without Npas4, long-term memories cannot form.

“Our study identifies an experience-dependent synaptic mechanism for memory encoding in CA3, and provides the first evidence for a molecular pathway that selectively controls it,” says Yingxi Lin, an associate professor of brain and cognitive sciences and a member of MIT’s McGovern Institute for Brain Research.

Lin is the senior author of the study, which appears in the Feb. 8 issue of Neuron. The paper’s lead author is McGovern Institute research scientist Feng-Ju (Eddie) Weng.

Synaptic strength

Neuroscientists have long known that the brain encodes memories by altering the strength of synapses, or connections between neurons. This requires interactions of many proteins found in both presynaptic neurons, which send information about an event, and postsynaptic neurons, which receive the information.

Neurons in the CA3 region play a critical role in the formation of contextual memories, which are memories that link an event with the location where it took place, or with other contextual information such as timing or emotions. These neurons receive synaptic inputs from three different pathways, and scientists have hypothesized that one of these inputs, from the dentate gyrus, is critical for encoding new contextual memories. However, the mechanism of how this information is encoded was not known.

In a study published in 2011, Lin and colleagues found that Npas4, a gene that is turned on immediately following new experiences, appears to act as a master controller of the program of gene expression required for long-term memory formation. They also found that Npas4 is most active in the CA3 region of the hippocampus during learning. This activity was already known to be required for fast contextual learning, such is required during a type of task known as contextual fear conditioning. During the conditioning, mice receive a mild electric shock when they enter and explore a specific chamber. Within minutes, the mice learn to fear the chamber, and the next time they enter it, they freeze.

When the researchers knocked out the Npas4 gene, they found that mice could not remember the fearful event. They also found the same effect when they knocked out the gene just in the CA3 region of the hippocampus. Knocking it out in other parts of the hippocampus, however, had no effect on memory.

In the new study, the researchers explored in further detail how Npas4 exerts its effects. Lin’s lab had previously developed a method that makes it possible to fluorescently label CA3 neurons that are activated during this fear conditioning. Using the same fear conditioning process, the researchers showed that during learning, certain synaptic inputs to CA3 neurons are strengthened, but not others. Furthermore, this strengthening requires Npas4.

The inputs that are selectively strengthened come from another part of the hippocampus called the dentate gyrus. These signals convey information about the location where the fearful experience took place.

Without Npas4, synapses coming from the dentate gyrus to CA3 failed to strengthen, and the mice could not form memories of the event. Further experiments revealed that this strengthening is required specifically for memory encoding, not for retrieving memories already formed. The researchers also found that Npas4 loss did not affect synaptic inputs that CA3 neurons receive from other sources.

Kimberly Raab-Graham, an associate professor of physiology and pharmacology at Wake Forest University School of Medicine, says the researchers used an impressive variety of techniques to unequivocally show that contextual memory formation is tightly controlled by Npas4.

“The major finding of the study is that contextual memory is driven by a single circuit and comes down to a single transcription factor,” says Raab-Graham, who was not involved in the study. “When they knocked out the transcription factor, they removed contextual memory formation, and they could restore it by adding the transcription factor.”

Synapse maintenance

The researchers also identified one of the genes that Npas4 controls to exert this effect on synapse strength. This gene, known as plk2, is involved in shrinking postsynaptic structures. Npas4 turns on plk2, thereby reducing synapse size and strength. This suggests that Npas4 itself does not strengthen synapses, but maintains synapses in a state that allows them to be strengthened when necessary. Without Npas4, synapses become too strong and therefore cannot be induced to encode memories by further strengthening them.

“When you take out Npas4, the synaptic strength is almost saturated,” Lin says. “And then when learning takes place, although the memory-encoding cells can be fluorescently labeled, you no longer see the strengthening of those connections.”

In future work, Lin hopes to study how the circuit connecting the dentate gyrus to CA3 interacts with other pathways required for memory retrieval. “Somehow there’s some crosstalk between different pathways so that once the information is stored, it can be retrieved by the other inputs,” she says.

The research was funded by the National Institutes of Health, the James H. Ferry Fund, and a Swedish Brain Foundation Research Fellowship.

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Progress continues toward a more diverse, inclusive MIT

Since a watershed meeting just over two years ago, when representatives from the Black Students’ Union and the Black Graduate Student Association met with President L. Rafael Reif, the administration has introduced a number of changes intended to enhance diversity and inclusion at MIT.

These changes have been guided by two sets of recommendations, one from the BSU and one from the BGSA, that emerged from this initial meeting. Many of the recommendations — particularly those involving orientation for incoming students, mental health services, implicit bias training, financial aid, and student surveys and data collection — have now been partially or completely implemented. Discussions are under way to address other recommendations for department-level actions, administration leaders have told MIT News.

The scope of individual recommendations has varied — from enhancing diversity orientation for incoming students to developing and implementing a 10-year plan to increase the number of graduate students from underrepresented minority groups — and thus so has the timeframe for responding to them, according to Vice President Kirk Kolenbrander.

“Many changes could be implemented relatively quickly, and they have been. Others must be addressed across departments that vary greatly in their size, organizational structure, and standard operating procedures, so these require creative thinking and a sustained effort,” Kolenbrander says.

A multifaceted response

Kolenbrander has convened an Academic Council working group, consisting of students, faculty, and senior officers, dedicated to addressing these recommendations. With DiOnetta Jones Crayton, the associate dean for undergraduate education and director of the Office of Minority Education, he has also convened another group to align staff who are advancing diversity and inclusion issues across the Institute. These groups have worked alongside Ed Bertschinger, the Institute’s community and equity officer, and Judy “JJ” Jackson, who joined MIT in 2016 as the diversity and inclusion officer.

The BSU and BGSA remain engaged in following up on their recommendations. The BSU’s political action committee, for example, is planning a survey to learn more about how the administration’s responses thus far have impacted students.

“MIT was very responsive and we’re very happy with the actions that have been taken, but we still want to make sure that the Institute remains accountable to the commitment that it’s made,” says third-year student Gabrielle Ballard, who co-chairs the BSU with third-year student Anthony Rolland and chairs the BSU political action committee.

“I hope that MIT will continue to engage with the students in order to figure out what the best plan is moving forward,” says Tsehai Grell, a BGSA member who has served on the group’s executive board and helped to draft the recommendations in 2015. “I’d like to see [Institute leadership] make sure student involvement continues. It has to be a unified effort. Everybody needs to be involved.”

Still other members of the MIT community have responded to the black student groups’ recommendations as well. For example, graduate student Ty Austin leads the diversity and inclusion subcommittee of the Graduate Student Council, which recently organized a network of students whose goal is to further diversity and inclusion efforts in academic departments.

When the BSU and BGSA presented their recommendations, the administration also invited other members of the MIT community to share additional ideas for making MIT a more welcoming, inclusive place. More than 90 are now under consideration or being actively addressed. For example, the Institute recently received permission from state authorities to launch a pilot program with four all-gender bathrooms on campus.

Enhancing mental health and counseling services

Both the BSU and BGSA have put forward recommendations for enhancing mental health and counseling services and hiring staff with expertise in race-based traumatic stress.

In October 2016, MIT hired Karen Singleton, who specializes in multicultural psychology and trauma, as chief of Mental Health and Counseling and associate medical director at MIT Medical. Three clinicians with expertise in race-based trauma have also been appointed: Cecil Webster Jr., Leslie Langston, and Erik Marks.

Recent activities by Mental Health and Counseling staff have included antioppression training for staff; the formation of a multicultural competency counseling team; development of a workshop series on the imposter phenomenon; a biweekly event called Let’s Chat@OME, which allows students to drop into the Office of Minority Education and talk with mental health and counseling staff; and biweekly therapy groups for graduate students of color. 

Orientation and implicit bias training

The Office of Multicultural Programs and the Office of Graduate Education (OGE) made a number of changes to the orientation programs for undergraduate and graduate students in the last two years.

In fall 2016 and 2017, incoming first-year students participated in small focus-group conversations on diversity and inclusion, facilitated by a trained conversation leader. MIT also began making modifications in fall 2016 to the graduate student orientation, including a dedicated networking reception for graduate students from underrepresented minority groups to meet senior leaders, faculty, and returning graduate students, and to learn about campus resources. The graduate students of color welcome planning committee is composed of graduate students, and OGE staff are beginning to discuss additional changes for 2018.

Implicit bias training, which the BGSA recommended for faculty, staff, and students, was launched in 2017 in several areas of the Institute, including the Institute Community and Equity Office, the Teaching and Learning Lab, Human Resources, Academic Council, and some academic departments.

Surveys and data collection

Other student recommendations related to collecting and sharing data about the MIT student body, broken down by race and other identity groups, could inform other efforts to further diversity and inclusion at the Institute.

These recommendations have led, for example, to the publication of a diversity dashboard, in cooperation with the Institutional Research section of the Office of the Provost. Targeted questions have also been added to key student surveys and the results made public. And, the Office of the Registrar is publishing a report on the number of underrepresented minority students by course and year on its enrollment page, which is available to members of the MIT community.

The BSU has also met with Stu Schmill, the dean of admissions and student financial services, to review data collected by that office and work together to plan new efforts to increase acceptance rates for students from underrepresented minority groups.

Financial aid

The BSU recommended increasing financial aid commitments to at least match peer institutions, reaffirming MIT’s commitment to keeping MIT education accessible through need-blind admission and a generous need-based financial system.

Over the last two years, MIT has increased financial aid expenditures by $23.4 million, from $97.3 million in FY16 to $120.7 million projected for FY18. The Institute has also reduced student self-help levels from $5,500 to $3,400 a year.

MIT continues to be unique in allowing low-income students to use Pell Grants to reduce or eliminate their self-help and summer savings expectations, and it guarantees that any family earning $90,000 or less will have scholarships that at least cover tuition. This guarantee serves more than one-third of MIT’s students.

Recruitment and retention

Both student groups have made recommendations around increasing diversity among graduate students and faculty, which involve a longer timeline. The BGSA, for example, recommended developing and implementing a 10-year plan to increase the number of underrepresented minority graduate students, in particular black graduate students.

“One thing that stands out to me is that to really increase the number of faculty members of color, we have to increase the number of graduate students of color. In the 2016-17 academic year, for example, only about 1 percent of MIT’s graduate students were black. We’d like to see a very concerted, coordinated effort to recruit graduate students of color,” says Candace Ross, a member and former president of the BGSA.

Thus far, every academic department has posted an online statement affirming its commitment to students’ health, diversity, and inclusion. Jackson and others have considered appointing diversity representatives who would implement such a 10-year plan, but MIT departments range widely in terms of size, organization, and recruitment and retention practices, so no uniform structure for all departments has been identified yet. A review of personnel in each department, to assess what may be feasible, is being considered, according to Jackson.

The BSU is keen to see how the departmental statements are put into practice, says Ballard: “Holistically, the goal would be seeing more students and faculty from underrepresented groups in those departments, and seeing [inclusionary practices extend even further], for example when professors are talking about people who have contributed to the field. It’s important for everyone to see that there’s a diverse range of voices that are in the STEM and humanities fields.”

“This is something that going forward we want to keep in mind, that diversity and inclusion doesn’t just stop at who you see. It’s what you’re talking about, the conversations you’re having,” she adds.

OGE has addressed the BGSA recommendations on multiple fronts. Staff have implemented a Graduate Diversity Ambassador program, increasing MIT’s presence at recruitment conferences across the country and providing personalized advice on MIT graduate applications to alumni of the MIT Summer Research Program (MSRP General) and CONVERGE. 

With input from the Office of the General Counsel, OGE implemented an expanded fee waiver policy during the 2016 application cycle to remove potential financial barriers for applicants who may not have considered MIT.

OGE is also renewing its commitment to the University Center for Exemplary Mentoring, which provides professional development activities to prepare doctoral students from underrepresented minorities for careers in academia. The OGE’s “Ignite Your Vision,” a monthly discussion series facilitated primarily by MIT faculty and alumni of color, touches upon general professional-development topics and provides an opportunity for graduate students to learn from the experiences of representatives from diverse career paths in industry, education, health care, and government.  

Most recently, OGE filled two diversity staff positions focused on maintaining MIT’s diversity recruitment efforts and providing bandwidth for the office to revamp its involvement in professional development. OGE plans to continue its collaboration with several academic departments and administrative offices at MIT, including Global Education and Career Development, to devise a targeted approach to addressing the BGSA’s recommendation that the Institute provide tailored resources to help graduate students from underrepresented minority groups compete successfully on academic and professional job markets.

A sustained effort

Members of the MIT community who have been engaged in furthering diversity and inclusion at the Institute agree that this work will need to continue for years to come.

“The students have not given up on these recommendations; they are not going to let them disappear,” Crayton says. “We have to continue to be thoughtful about them. If there are things we cannot do, or cannot do right away, we have to be very transparent about sharing that information. That’s what will build stronger relationships.”

Work on inclusion is inherently a constant process, Jackson says.

“When I look at these recommendations, what I see the students are looking for is an equitable opportunity for everyone to be free and unfettered to do their best at MIT and make a contribution to the community,” she says. “Inclusion does not first demand that you be like somebody else. It says whoever you are, bring the best of you into the community and let’s together help to make MIT a better place if MIT is going to help make a better world.”

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EAPS welcomes Heising-Simons fellow Ian Wong

The Department of Earth, Atmospheric and Planetary Sciences (EAPS) is looking forward to welcoming planetary scientist Ian Wong, one of the 51 Pegasi b Postdoctoral Fellows for 2018 announced this week by the Heising-Simons Foundation.

Named for the first exoplanet discovered orbiting a Sun-like star, the new 51 Pegasi b Fellowships are intended to give exceptional postdoctoral scientists the opportunity to conduct theoretical, observational, and experimental research in planetary astronomy.

Wong will be hosted at MIT by the Binzel Group in EAPS. Led by Margaret MacVicar Faculty Fellow and Professor of Planetary Sciences Richard P. Binzel, who is one of the world’s leading scientists in the study of asteroids and Pluto, the group’s research focuses on theory, computation, and data analysis of planetary bodies throughout the solar system.

Wong’s work seeks to decipher the history of our solar system by studying its most primitive bodies. 

A visit to the Palomar Observatory as a first-year graduate student cemented Wong’s commitment to observation and hands-on data collection. His observational research focuses on small, icy asteroids in the middle and outer regions of our solar system. Astronomers consider these primitive bodies to be the building blocks of planets, providing a window into the earliest stages of our solar system — and perhaps even into the origins of life on Earth.

By studying the physical and chemical properties of these objects, Wong is working to infer details about the environment in which they formed, and uncover evidence that may support recent theories suggesting that the entire solar system once rearranged itself through a chaotic, dynamical event. Enhancing knowledge of our own solar system’s history in these ways can also help explain the observed diversity among exoplanet systems.

During his fellowship, Wong will investigate Kuiper Belt objects beyond the giant planets, as well as the Trojan and Hilda asteroids near Jupiter. He will compare the composition of these bodies to test theories of solar system formation and evolution. His planned research coincides withe the 2021 launch of Lucy, NASA’s first space mission to study Jupiter Trojans. 

The Trojans are a population of primitive asteroids that orbit in tandem with Jupiter in two loose groups around the Sun, with one group always ahead of Jupiter in its path, the other always behind. At these two so-called Lagrange points, the bodies are stabilized by a gravitational balancing act between the Sun and Jupiter. Lucy’s complex path will take it to both clusters. Over 12 years, with boosts from Earth’s gravity, the spacecraft will journey to seven different asteroids in total — six Trojans and one from the Main Belt. 

“These exciting worlds are remnants of the primordial material that formed the outer planets, and therefore hold vital clues to deciphering the history of the solar system,” Binzel says. Scientists hope that Lucy, like the human fossil for which the mission is named, will revolutionize the understanding of our origins.

“No other space mission in history has been launched to as many different destinations in independent orbits around our Sun. Lucy will show us, for the first time, the diversity of the primordial bodies that built the planets, opening up new insights into the origins of our Earth and ourselves,” Binzel says.

Wong explains that NASA’s Lucy mission “is a really big boon for my particular sub-field. On a fundamental level, it shows the importance of these not commonly studied objects. Throughout my fellowship, I hope to contribute important groundwork for interpreting the results of this probe.” 

The big scientific question Wong will be chasing over the next three years is whether these asteroid populations are related to each other. While the traditional model of solar system evolution holds that these objects formed where they are, new insights have led scientists to theorize that an episode of dynamical instability completely rearranged the solar system.

“If that is the case, then all of the middle and outer solar system minor bodies should have formed within a single primordial population of asteroids beyond the ice giants, before being scattered into their current locations by the dynamical instability,” Wong says. “Exploring this is crucial to explaining details of solar system architecture that are left unanswered by the traditional model.”

Wong graduates from the California Institute of Technology in February 2018 with a PhD in planetary science. He holds a BA in linguistics from Princeton University.

The seven other 2018 51 Pegasi b Fellows and their host institutions are: Marta Bryan, University of California at Berkeley; Sivan Ginzburg, University of California at Berkeley; Thaddeus Komacek, University of Chicago; Aaron Rizzuto, University of Texas at Austin; Christopher Spalding, Yale University; Jason Wang, California Institute of Technology; and Ya-Lin Wu, University of Texas at Austin.

Each award provides up to $375,000 of support for independent research over three years, the time and freedom to establish distinction and leadership in the field, mentorship by an established faculty member at the host institution, and participation in an annual summit to develop professional networks, to exchange ideas, and to foster collaboration.

EAPS department head Robert van der Hilst says he is delighted that the Heising-Simons Foundation chose MIT as one of the five institutions to host the fellowship: “We are excited to welcome Ian to MIT. We are sure that his research will have an impact on our understanding of our solar system, and are honored and proud for EAPS to have been invited to host a Heising-Simons Foundation 51 Pegasi b Postdoctoral Fellow again this year.”

The Heising-Simons Foundation is a family foundation based in Los Altos, California. The foundation works with its many partners to advance sustainable solutions in climate and clean energy, enable groundbreaking research in science, enhance the education of our youngest learners, and support human rights for all people. More information about the foundation is available at www.heisingsimons.org. To learn more about the fellowship, and its four inaugural fellows, please visit www.51pegasib.org.

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Lessons in learning

Instead of flipping the classroom — viewing lectures in advance and using class time to solve problems — Carl Wieman ’73 flipped the audience at the second annual MIT Festival of Learning. To reach students, the kickoff speaker said he retooled his standard faculty talk about new approaches to teaching.

After all, they “often have more expertise on learning than most faculty do,” he said.

Wieman, a Nobel Prize-winning Stanford physicist, urged the hundreds of students in the audience to take control of their own education at the Jan. 29 event. In other words, he added, “hold faculty and administrators more accountable” when teaching is not up to snuff.

Wieman knows of what he speaks. When he realized the students in one of his atomic physics classes were not mastering fundamental concepts, he investigated ways to improve his teaching — a journey he describes further in his book, “Improving How Universities Teach Science.” Decades of research in cognitive and learning sciences, he discovered, revealed that having students take notes based upon lectures (what Wieman calls “filling the brain”) is one of the least effective ways to learn. So, he abandoned traditional classroom lecturing.

Instead, active learning, or group and problem-based teaching with a focus on timely feedback, works better. He has seen the positive results in his own classes, as well as via longitudinal studies he has co-authored. Wieman feels that the goal should be to teach students “how to be experts” by helping them understand what tools, resources, and knowledge to use when tackling real problems. After all, that’s what experts like him, and other faculty and researchers, do in their labs.

Asking students to solve typical exam problems without calculators, notes, or instruments, “as if they were shipwrecked on an island,” is both artificial and arbitrary. Moreover, Wieman added, “real knowledge does not come with chapter numbers,” so teaching to the test does not provide students with ways to cope with novel situations.

Like learning, teaching requires expertise. Too often, he said, faculty are not given the time, opportunity, or right incentives to develop their teaching skills. This leads to learning environments akin to medicine in the mid-19th century, when “anyone who simply did things to people” could be considered a doctor. Switching his tone at the end of this talk and eyeing the administrators in the room, Wieman said that universities need to move away from the “pedagogical equivalent of bloodletting” and take steps to put effective and evidence-based teaching front and center.

After his lecture (or “sermon,” as he called it), Wieman’s message was amplified by a series of lightning-round talks by MIT faculty who have embraced innovative teaching. Anette “Peko” Hosoi, associate dean of engineering and the Neil and Jane Pappalardo Professor of Mechanical Engineering, provided an update on the New Engineering Education Transformation (NEET) pilot initiative, centered around interdisciplinary projects to prepare students for the practice of engineering, specifically in emerging areas such as autonomy and living machines. Each speaker talked about the dual benefit of such experiments: enhancing the student experience as well as reinvigorating their own on-campus teaching in different ways by making their students’ learning much more active.

Inspired by the goody bags his 6-year-old daughter receives at friends’ birthday parties, Jeffery Grossman, the Morton and Claire Goulder and Family Professor in Environmental Systems, created hands-on experimental kits for 3.001 (Introduction to Materials Science and Engineering). Filled with simple components, common agents like vinegar, and instructions, students were given an opportunity to explore even the most theoretical topics in tangible ways, from the makeup of metals to chemical structures. “I was thrilled when I saw a group of students dousing various metals in the Infinite Corridor with vinegar,” Grossman said. (For those who are curious, example bags are on display in the Infinite Corridor).

Three faculty, Shigeru Miyagawa, Thomas Kochan, and Barton Zweibach, all zeroed in on ways they have used technology to go beyond the walls of the classroom. Miyagawa, a professor of linguistics and the Kochi-Manjiro Professor of Japanese Language and Culture, incorporates digital images from dozens of museums and collections and draws upon worldwide experts in Visualizing Japan, a flipped-format online and residential experience.

For an assignment to develop a new employment bill of rights that reflects the changing economy, Kochan, the George Maverick Bunker Professor of Management, uses social platforms to virtually mix MBA students with workers in the field, adding an eye-opening real-life dimension to their training. Finally, Zweibach, a professor of physics, has retooled a sequence of courses in quantum physics (8.04, 8.05, and 8.06) via MITx to allow students more flexibility about how and when to take them.

Vice Chancellor Ian A. Waitz, who oversees undergraduate and graduate education at MIT, wrapped up the round. He spoke about an effort to improve the first year experience for undergraduates through a design class where the topic students will tackle is the first year itself. At the end of the course, they will present rigorous, evidence-based recommendations to MIT’s senior leadership. Waitz is pleased about students’ eagerness to take on the challenge, adding, “We were hoping for at least 20 students, booked a classroom for 55, and are now anticipating around 100.”

The rest of the festival, which was sponsored by the Office of Digital Learning and the Office of the Vice Chancellor, was less formal. Participants had a chance to mill around Lobby 10 and Lobby 13 to view 29 exhibits about current efforts, including digital teaching tools, a lightboard to capture video lectures, and even comic books for graduate researchers.

Susan Silbey, chair of the faculty and the Leon and Anne Goldberg Professor of Humanities, professor of sociology and anthropology, and professor of behavioral and policy sciences at the Sloan School of Management, found the festival “just marvelous.” She said she senses that a “revolution” is taking hold at MIT. “It seems that everyone is stepping up, and this is just a snapshot of what’s happening across campus,” she said.

Woodie Flowers, the Pappalardo Professsor Emeritus of Mechanical Engineering, closed the daylong event with a playful talk titled “Nerd Epistemology,” noting that faculty have actually been stepping up for decades. The creator of 2.007 (Design and Manufacturing) — often considered the first design class at MIT and the inspiration for another iconic class, 2.009 (Product Engineering Processes) — punctuated his remarks, in true MIT fashion, with examples and data. Among them were a video clip featuring Megan Smith ’86 and SM ’88, the former chief technology officer of the United States, describing how 2.007 inspired her to pursue engineering.

Another example he cited, which extends well beyond MIT, is the FIRST robotics competition for elementary and high school students. Founded by Flowers and Dean Kamen in 1989, the competition draws on the magic of 2.007 and 2.009 and shows how it can be scaled; the FIRST competition now engages over 500,000 elementary and high school students each year.

A true trailblazer, Flowers wrote about flipped learning with multimedia back in the 1980s. He shared that he hoped that by now traditional teaching would be a thing of the past and active, hands-on learning would be standard. Nonetheless, he sees that continued advances in areas such as artificial intelligence will move the needle forward.

Above all, Flowers said, meeting Wieman’s litmus test requires not only technology or techniques, but an attitude shift. An advocate of “gracious professionalism,” Flowers stressed that respecting the planet and other people needs to ground all teaching and learning.

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Cities of the future may be built with locally available volcanic ash

MIT engineers working with scientists in Kuwait have found that volcanic rocks, when pulverized into a fine ash, can be used as a sustainable additive in concrete structures.

In a paper published online in the Journal of Cleaner Production, the researchers report that, by replacing a certain percentage of traditional cement with volcanic ash, they can reduce a concrete structure’s “embodied energy,” or the total energy that goes into making concrete. According to their calculations, it takes 16 percent less energy to construct a pilot neighborhood with 26 concrete buildings made with 50 percent volcanic ash, compared with the energy it takes to make the same structures entirely of traditional Portland cement.

When they ground volcanic ash down to increasingly small particle sizes, the researchers found that a mixture of the finer powder and Portland cement produced stronger concrete structures, compared with those made from cement alone. However, the process of grinding volcanic ash down to such fine particles requires energy, which in turn increases the resulting structure’s embodied energy. There is, then, a tradeoff between a concrete structure’s strength and its embodied energy, when volcanic ash is used.

Based on experiments with various concrete and volcanic ash mixtures, and calculations of the resulting structure’s embodied energy, the researchers have mapped out the relationship between strength and embodied energy. They say engineers can use this relationship as a blueprint of sorts to help them choose, for instance, the percent of cement they would want to replace with volcanic ash to produce a given structure.

“You can customize this,” says Oral Buyukozturk, a professor in MIT’s Department of Civil and Environmental Engineering (CEE). “If it is for a traffic block, for example, where you may not need as much strength as, say, for a high-rise building. So you could produce those things with much less energy. That is huge if you think of the amount of concrete that’s used over the world.”

Buyukozturk is joined on a  paper by an interdisciplinary team of researchers, including research scientist Kunal Kupwade-Patil and undergraduate Stephanie Chin of CEE, former doctoral student Catherine De Wolf and Professor John Ochsendorf of MIT’s Department of Architecture, Ali Hajiah of the Kuwait Institute for Scientific Research, and Adil Al-Mumin of Kuwait University.

A natural additive

Concrete is the most abundantly used material in the world, second only to water. The manufacturing of concrete involves first blasting rocks such as limestone out from quarries, then transporting the rocks to mills, where they are further crushed and treated under high temperature through various processes resulting in the production of cement.

Such energy-intensive processes create a significant environmental footprint; the production of traditional Portland cement accounts for about 5 percent of the world’s carbon dioxide emissions. To cut down on these emissions, Buyukozturk and others have been looking for sustainable additives and alternatives to cement.

Volcanic ash has several sustainable advantages as an additive in manufacturing concrete: The rocky material, which lies in ample supply around active and inactive volcanoes around the world, is naturally available; it is typically considered a waste material, as people typically do not use it for any widespread purpose; some volcanic ashes have intrinsic, “pozzolonic” properties, meaning that, in powder form, the ash with a reduced amount of cement can naturally bind with water and other materials to form cement-like pastes.

“Cement production takes a lot of energy because there are high temperatures involved, and it’s a multistage process,” says Chin, who with Kupwade-Patil led much of the group’s experimental work as a student in the Undergraduate Research Opportunities Program (UROP) with Buyukozturk. “That’s the main motivation for trying to find an alternative. Volcanic ash forms under high heat and high pressure, and nature kind of does all those chemical reactions for us.”

The team looked first at how much energy it would take to make concrete from a mixture of cement and volcanic ash, versus cement alone. To do this, the researchers consulted several databases in which others had calculated the embodied energy associated with various industrial processes, such as the energy that goes into crushing rock or curing cement. The researchers picked through the databases to assemble the individual processes associated with producing traditional cement and cement containing 10 to 50 percent volcanic ash.

They then went into the lab, where they manufactured small samples of concrete with various percentages of volcanic ash, as well as samples made only of Portland cement. Chin and her colleagues subjected each sample to standard tests of strength, such as compressing the structures until they began to crack. Then they mapped out each sample’s strength against its calculated embodied energy.

According to their results, replacing 50 percent of traditional cement with volcanic ash with an average particle size of 17 micrometers can bring down concrete’s embodied energy by 16 percent. However, at this particle size, volcanic ash can compromise concrete’s overall strength. Grinding the ash down to a particle size of about 6 micrometers significantly increases concrete’s strength, as smaller particles provide more surface area with which water and cement can chemically bind.

Cities of ash

The team extrapolated its results to see how structures made partly with volcanic ash would affect concrete’s embodied energy at the scale of entire buildings and neighborhoods.

The researchers focused on a neighborhood in Kuwait with 13 residential and 13 commercial buildings, all made with traditional Portland cement, mostly imported from Europe. With the help of their collaborators in Kuwait, they flew a drone over the neighborhood to collect images and measurements. They also consulted local authorities, who provided them with additional information on each building system.

Using all this information, the team calculated the neighborhood’s existing embodied energy, and then calculated how that embodied energy would change if buildings were made with concrete composed of various percentages of volcanic ash, which is in ample supply in the Middle East.

As with their experiments in the lab, they found that a neighborhood’s infrastructure can be made with considerably less energy if the same buildings are built with concrete made from a cement mixture that is 30 percent volcanic ash.

“What we’ve found out is that concrete can be manufactured with natural additives with desired properties, and reduced embodied energy, which can be translated into significant energy savings when you are creating a neighborhood or a city,” Buyukozturk says.

This research was supported in part by the Kuwait Foundation for the Advancement of Sciences. The project was conducted as part of the Kuwait-MIT signature project on sustainability of Kuwait’s built environment for which Buyukozturk was the principal investigator.

Undergraduates share authorship

In a second paper, which will soon appear in the ASCE Journal of Materials in Civil Engineering, co-authors Chin and Maranda L. Johnston, also a former UROP student, explore the binding mechanism involved when Portland cement is replaced with finely ground volcanic ash. The team used various techniques including synchrotron X-Ray diffraction at Argonne National Laboratory to examine the microstructure of hardened cement pastes.

They found the finer-sized volcanic ash particles produced nanometer-scale products within the cement paste as it hardened, which helped to densify the matrix as it cured. “Our work provides a basis for the engineers to optimize their mixes with natural additives according to their specified requirements,” Kupwade-Patil says.

“It has become in a way a tradition in my laboratory to involve freshman and other UROP students in high-level multidisciplinary research leading to journal publications,” Buyukozturk says. “This learning experience is an important part of our educational system.”

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Undergrads gain experience in energy sector with MITEI member companies

MIT undergraduates who interned with MIT Energy Initiative (MITEI) member companies in summer 2017 had the chance to work abroad on a wide range of energy projects, from analyzing fuel additives to evaluating how new technologies might transform energy markets.

Along the way, the interns — all participants the MIT International Science and Technology Initiatives (MISTI) program — learned basic life lessons, experienced other cultures firsthand, and gained insights into the energy industry. This deep dive into the working world overseas is a hallmark of MISTI, the Institute’s renowned program in applied international studies.

“MISTI helped me explore the world and get a global perspective,” says Ignacio Ortega, who spent eight weeks interning at Iberdrola in Madrid. “That’s something I want to have because in the future I want to start my own company,” says the second-year mechanical engineering major, who plans to complete an energy studies minor and enter the energy industry.

This is the fifth straight year that MITEI and MISTI have teamed up to provide interested students with energy internships abroad. This summer, the partnership sent eight students abroad to MITEI members: six to Shell in India, one to Shell in Germany, and one to Iberdrola in Spain.

“MISTI opens the world to MIT students by offering a robust portfolio of possibilities in energy — from looking at solar energy in remote Himalayan villages that have no electricity to working in the research and development heart of Bangalore with global companies such as Shell,” says Mala Ghosh, managing director of MIT-India and MIT-South Asia, and MISTI liaison for the MISTI-MITEI internship program.

Ghosh notes that the MITEI interns were among roughly 50 MIT students who did energy-related work overseas during summer 2017 through MISTI. Overall, MISTI placed 1,250 students — 469 graduate students and 781 undergraduates — in internships and research posts around the world this year.

Professional skills for students

“It’s been an adventure,” says Carissa Skye, a third-year physics major working at Shell in Hamburg, Germany. Skye says the MISTI internship provided “a crash course on adult life” — from finding an apartment to filling out German bank forms — and also made it possible to gain professional experience applying machine learning algorithms to the task of predicting the fluctuation of energy-related stock prices.

The data analysis skills acquired for that project will be crucial for a career in physics, Skye says. “Data analysis is more and more important in the world of physics as physics experiments get bigger and more technical,” says Skye, noting that a wealth of data is pouring in from CERN and other particle accelerators. “Physics education on the undergraduate level doesn’t have a good way of giving us that.”

Amy Zhang, a second-year computer science major, says working for Shell in Bangalore, India, gave her a new view on her career options. “It was interesting to work in a really interdisciplinary field — using data mining for a company not thought of as a computer science company,” says Zhang.

Zhang’s main project for Shell was developing a computer program that can identify potential fuel additives. “Long-term screening for fuel additives is really expensive, both in financial terms and in terms of time,” she says. “I was part of the computational chemistry team using machine learning to classify molecules on the computer so they wouldn’t have to test each fuel with every additive.”

Zhang says she enjoyed the MISTI internship in part because she got to work on a project with real-world applications. Since the fuel additives may one day show up in consumers’ gas tanks, she says, “what I was working on has the potential to impact a lot of people.”

Fresh perspectives

Internships such as these show students that it’s possible to work for a corporation and still do experimental research, says Ghosh. And, while students gain new skills and international experience, sponsors gain fresh insights into their own energy challenges.

“MIT students bring their knowledge and intellectual capacity, as well as their innovative spirit, to Shell. This is very much appreciated by our Shell colleagues, who are also innovating on a daily basis for more and cleaner energy resources,” says Haibin Xu, external research and innovation manager for Shell in the United States.

“We rely on programs like MISTI to help connect us with students from across the globe to not just intern for us but also to teach us their views,” says Beatriz Crisóstomo Merino, head of innovation management at Iberdrola. “Iberdrola enjoys the fresh perspective, ideas, hands-on skills, and enthusiasm of MIT students. Students and hosts can contribute to innovative solutions together.”

For example, Ortega spent much of his internship working with Iberdrola researchers on a white paper exploring how Iberdrola could use blockchain — a digital ledger technology — for such energy-related transactions as buying and selling energy to the grid. “This would enable the utility to better price energy they’re selling based on demand and supply in the market,” says Ortega. “It furthers the efficient use of energy.”

Skye, meanwhile, found that Shell in Germany is working to meet government regulations that call for an 80 percent cut to carbon dioxide emissions from the home heating sector by 2050. To that end, Skye worked on a project (in addition to the one that involved data analysis) to standardize the reporting of experimental data related to the efficiency of solar panels.

Notably, Skye was surprised to learn that Germans seemed to accept climate change and the need for alternative sources of energy as indisputable facts; in the United States, Skye finds that people are less convinced. “In Germany, they know solar needs to start now, wind power needs to start now. It’s interesting to see that cultural difference,” says Skye.

While her main project centered on traditional fuels, Zhang was also involved in a smaller project modeling how lithium-sulfur batteries charge and discharge over time — work applicable to the storage needs of such renewable energy sources as wind and solar. “Working in an area that’s making the possibility of sustainable energy a reality was pretty cool,” says Zhang.

For the companies, sponsoring interns not only advances projects like these, but also provides a platform for recruiting, access to MIT’s research community, and opportunities to develop collaborative ventures with MIT faculty and students. “Our host companies are excited to work with our students,” says Ghosh. “Our MITEI interns have outperformed expectations.”

That’s why plans are already under way for MISTI-MITEI to support more internships next year. “Companies are looking to increase their numbers and expand into a variety of countries, including Brazil, China, Mexico, and the U.K.,” says Ghosh.

The bottom line, she says, is: “Senior researchers come back asking for students to continue research remotely while back at MIT, co-author papers, join as full-time hires, and to send more student interns each year. They are impressed with the caliber of work.”

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