We are teachers, leaders, researchers, advisors, business professionals and students. Welcome to Northeastern’s College of Science

More Filters




The layers of science behind every World Cup kick

The beginnings of the 2022 FIFA World Cup have been filled with dramatic moments, including shocking underdog victories by Saudi Arabia and Japan. Now, as focus settles on the 16 teams that advanced to the tournament’s knockout stage, every kick and every goal has the razor-sharp ability to cut a nation’s run just short of international soccer acclaim.

Every kick is filled with layers and layers of science – from the physics of the ball’s trajectory, to the neuroscience behind learning how to control and kick a ball, to the sports psychology of training and practice regiments that inform each decision a player makes on the field.

The basic idea of soccer flies in the face of millions of years of evolution. Evolutionary ancestors first standing up on two feet was a defining moment in human evolution. It freed our hands for other tasks beyond standing and moving. This allowed humans to develop a rich catalog of manual skills, including hunting, using tools, controlling fires, and playing modern sports like American football, hockey, basketball, tennis — but not soccer. Instead, soccer engages the feet in not only locomotory movements but specificallyin manipulating the ball.

“To now have a game where hands and arms are excluded from touching the ball is turningeverything upside-down,” said Dagmar Sternad, a Northeastern biology professor and the director of the Action Lab. “Playing soccer involves skills with their feet that a human being of this day and age has left behind and forgotten.”

Soccer players learn each ability in the foot skillset through years of practice. In the same way a child learns how to write the alphabet, soccer players learn to kick a soccer ball with perfect technique. Researchers in motor neuroscience, who study how the brain controls movement, aim to understand how a very specific skill is learned: The simple concept is that each sensorimotor behavior becomes somehow engrained in the neural network of the brain. But researchers in the field are still mystified by how that skill is adapted and generalized to different variations and contexts.

For example, Mario Pašalić of Croatia kicked a stationary ball past Japan’s goalkeeper, dashing Japan’s World Cup hopes in the tournament’s first tie-breaking round of penalties, by performing the extensively practiced motions of a penalty kick without any disturbances from other players. But in the thralls of dynamic mid-game goal attempts, Pašalić has to modify his kicking skill in the face of other players trying to interfere and adapt it to shoot more to the left or right, or even curve the trajectoryof the ball to land in the goal.

It’s called the Magnus effect — adding a spin to the ball to cause its trajectory to curve. As the ball spins while flying through the air, it whips air over the side spinning in the direction of the airflow. The other side slows the air as it spins against the airflow. Bernoulli’s principle states that faster-moving air has lower pressure than slower-moving air. (Daniel Bernoulli derived this from energy conservation: the more kinetic energy from motion, the less pressure energy). This means the faster-air side of the ball has a lower pressure than the slower-air side. Consequently, the higher-pressure side pushes the ball toward the lower-pressure side, causing the ball to curve.

It’s the same reason an airplane can fly, with faster-moving air above the wing and slower-moving air below it, creating higher pressure below the wing and pushing it up. It’s also the same reason that the high air speeds of a hurricane can blow out your windows, said Northeastern physics professor Arun Bansil.

“You can call it lift, you can call it the Magnus effect, but the basic physics is exactly the same,” said Bansil. “Whether the difference in speed is caused in the fluid by the object’s rotation, the shape of the object, like with an airplane, or just simply the air going fast outside a window.”

Players use the effect in all directions. Topspin sinks the ball downwards, backspin pushes it up, sidespin twists the ball to the side. The more years of practice a player has, the more these complex kicking skills feel like second nature, freeing up mental space to make tactical decisions on the field, adapt to extenuating circumstances, and assess risks to lower the chances of injury.

As professional soccer careers get longer and longer, athletes focus on reducing the risks of injury to extend the potential length of their careers. Beyond game-day decisions, this conscious health approach involves science-backed strict dietary practices (including that odd spitting thing), consistent sleep schedules, and individual fitness regimens with personal trainers. Focusing on injury-risk reduction requires full mental focus, uninterrupted by the psychological pressures of an important game, like those of the World Cup.

“If people become very tense because they play England or Germany, there is this additional adrenaline that can have a positive or not-so-positive effect depending on its intensity,” said Sternad. “That also can makepeople more prone to injury because their decisions are not as much guided by what they’ve practiced in training but rather what that special moment brings about.”

But the adrenaline is not likely a barrier for World Cup players, Sternad and Salah Bazzi, a research scientist at theInstitute for Experiential Robotics and the Action Lab, hypothesize. All of these players are “good test-takers,” able to take what they have learned on the practice field and apply it consistently when tested on the international stage of the World Cup.

“I think as the tournament continues to proceed toward the final stages, what separates the superstars from the stars are those that rise to the occasion. They can score the decisive goal in those important moments. They don’t choke under pressure,” said Bazzi.

December 08, 2022

Research shows idea that mind and body are separate is natural — for neurotypical people

A new research paper by Northeastern professor Iris Berent demonstrates that the idea that the mind and body are separate and distinct rises naturally in people who are neurotypical and is not just the result of culture or environment.

People with autism are more likely to see the body and mind as one, according to the study in the Nov. 30 issue of the Proceedings of the National Academy of Sciences, which Berent conducted with Rachel Theodore,  a professor from the University of Connecticut and a Northeastern graduate.

Berent, who has a Ph.D. in cognitive psychology,  says the results have profound implications for how people think about science, religion and psychiatric disorders.

“It really affects how we think about everything,” she says.

Berent called the distinction between body and mind dualism.

“Dualism is the belief that the mind is somehow separate from the body, that the body’s physical but the mind is something else,” she says.

“It turns out that even young children have these beliefs, and it doesn’t look like something that is just in Western culture. We find it across cultures.”

Berent says the paper is the first to show that a basic psychological mechanism that is critical for social interactions, called “theory of mind,” is responsible for neurotypical people viewing the mind as separate from the body.

Theory of mind gives people the ability to recognize emotions, desires, beliefs and knowledge in themselves and other people and infer others’ intentions.

“You kind of infer what the other person is thinking or feeling by watching their actions,” Berent says.

Even young infants demonstrate theory of mind, she says.

“Three-month-olds, for instance, prefer a creature that helps another climb a hill to a creature that hinders the climber’s action. This suggests that infants perceive creatures in terms of their goals, such as seeking to climb a hill, or helping/hindering others,” Berent says.

Autistic people score lower on theory of mind social-cognitive skills, which is why they are often perceived as having social  problems, Berent says. And these problems in “reading” the minds of others lead autistic people to view other people’s minds as less distinct from their bodies.

In her study, researchers asked autistic and neurotypical people to imagine it would be possible to create a replica of their body in the future. Participants were asked which of a person’s psychological characteristics would likely emerge in the replica—their thoughts or their actions.

“Autistic participants believed that thoughts would transfer to the replica more than neurotypicals,” Berent says.

In a second experiment, participants were asked to imagine which of the person’s traits will persist in the afterlife—after the body’s demise. In this case, only neurotypical, but not autistic people, thought that the person’s thoughts would persist.

“Autistic people tend to view thoughts as more strongly anchored in the body,” Berent says.

“Neurotypicals, by contrast, are more dualists—they consider thoughts as separate from the body” and, therefore, they believe thoughts can persist without the body, in the afterlife—but not in the person’s body and its replica, Berent says.

Dualism can be connected to the idea that there is life after death and that a soul exists separately from the body, she says.

But dualism also results in problems understanding science and treating psychiatric disorders, for which patients are often stigmatized and blamed even though the disorders originate in the brain, Berent says.

“This is the first study to link this thinking about bodies and minds to something that is core to the human psyche, to theory of mind.”

It may be natural, but there’s a cost to society and scientific understanding when body and mind are unyoked, Berent says.

Dualism is part of the reason people view mental health differently from what they consider physical health, she says.

But “science tells us that psychiatric disorders are diseases. Like all other diseases, they are part of the body.”

This article originally appeared on [email protected]

Photo by Getty Images.

December 07, 2022

Republicans had higher COVID-19 death rates in the first year of the pandemic, new research says

The COVID-19 pandemic has been defined not only by its outsized impact on the lives of people all over the world. In the U.S. the global pandemic has become a polarizing political issue, with misinformation flying far and wide on social media.

Now, new research suggests that politics played a significant role in who was dying early in the pandemic.

Mauricio Santillana, a professor of physics at Northeastern who specializes in epidemiology, and a team of researchers tracked trends in COVID-19 death rates during the first year of the pandemic. What they found was that deaths spiked in well-connected, Democrat-heavy cities early in 2020, but that by the first pandemic winter, deaths were about three times higher in Republican leaning—and specifically Trump-leaning—areas of the country.

“In epidemiology, when you see 10% or 20% higher, you worry, but when you see threefold differences, then you panic,” Santillana says.

Strikingly, the researchers found that the median death rate for counties with the strongest Republican leaning was between 40% and 300% higher than the counties that leaned Democrat. Santillana says the stark differences are symptomatic of a public health crisis that has been heavily politicized.

“Something that became clear very early on in the pandemic was that people were listening to different voices,” Santillana says. “As a consequence, what started as a public health crisis started becoming a crisis that was determined more by the political affiliation that people had.”

In that way, the COVID-19 pandemic is different from past pandemics, he says. Typically, epidemiological models don’t even take into account the political leaning of communities. In this case, Santillana and the rest of the research team set out to document the vital role that political affiliation played in the devastation of the pandemic.

As part of their research, the team created models based on death counts from the country’s 2,000 counties that looked at factors ranging from socioeconomic status to obesity. Even when controlling for every other variable, the team found that political affiliation factored heavily in the death rate.

“We started monitoring how the different communities that aligned better with certain political affiliations started showing big differences in the way they were behaving, and we were concerned that would lead to different outcomes, some outcomes that would be regrettable, namely higher rates of mortality,” Santillana says. “We started realizing that political affiliation was an important factor in an epidemic outbreak, something that in prior outbreaks hadn’t been as explicit as it was during COVID-19.”

Between February 2020 and February 2021, the focus of this research, 462,475 people died from COVID-19 nationwide. Regionally, the story looks different in that time period.

In the Northeast, the majority of deaths, 51%, were in the first four months, when COVID-19 first arrived in the states and spread rapidly. Deaths decreased during summer 2020 as the CDC recommended mask wearing and states adopted mask mandates and social distancing policies were put in place. Meanwhile in the South, in the same period, deaths rose in the summer and peaked in the winter, with 57% of deaths occurring between October 2020 and February 2021. Deaths in the Northeast also rose slightly in winter 2020, but not to the same degree as the South. Santillana says this is when the link between behavior, inspired by information and misinformation, and its impact on COVID-19 outcomes can be most clearly seen. (The research draws on Johns Hopkins University’s COVID-19 data portal.)

“We realized that people who were listening to the stronger voices coming from the Republican party, specifically from Donald Trump, were dismissing the gravity of contracting COVID-19 and were dismissing the usefulness of masks and social distancing,” Santillana says. “Sadly, that led to much worse outcomes in those communities.”

Justin Kaashoek, the lead author on the research, says that based on the discourse around vaccines and boosters, the pandemic is still heavily politicized. However, he hopes this research can help avoid a similar story in the future.

There are still people who are dying from this disease, and there’s going to potentially, hopefully not in our lifetimes, be another pandemic,” Kaashoek says. “How do we make sure our political differences don’t get in the way of something that is strictly not political and shouldn’t be?”

During a panel organized by the University of Cambridge’s philosophy panel, Santillana admits his usual optimism was shaken when a member of the audience suggested that “what happened during COVID is intrinsic to societies working as political systems.”

“I have this optimistic perspective … that if we were only able to share the consequences in a transparent way, everyone should be able to digest the information and conclude that we should behave differently,” Santillana says. “But in our current system, when vaccines were rolled out, even though we were presenting the studies showing their advantages … still people were choosing to believe or not believe. Can we really hope for a better outcome in the next [pandemic], which will occur at some point?”

This article originally appeared on [email protected]

Photo by Anthony Behar/Sipa via AP Images

December 05, 2022

Are volcanoes impacted by climate change? Or is it the other way around?

The eruption of Mauna Loa for the first time in 40 years on the Big Island of Hawaii follows a summer and fall that saw record-high temperatures around the world.

Is there a connection between climate change and volcanic eruptions?

While a study of Iceland proposes a possible link, scientists at Northeastern University say the effect of volcanic activity on global warming is minimal.

Daniel Douglass and Samuel Munoz of Northeastern’s Marine Science Center and Coastal Sustainability Institute say the impact operates in reverse: major explosions of volcanoes in the past have decreased global temperatures by a degree or two for months.

The effect is so pronounced that some scientists want humans to duplicate the effect through geoengineering; but Douglass and Munoz say that scenario is nowhere near reality at this time.

“People do say this is something we should research and think about,” says Douglass, an associate professor of geology. “A bunch of other people say that seems really dangerous.”

The idea is to create a sort of umbrella over the earth that would block solar radiation from reaching the ground.

“The sunlight bounces back into space,” Douglass says.

Major volcanic explosions have created this effect naturally by shooting giant plumes of ash and sulfuric acid into the atmosphere, where the latter forms aerosol particles or little droplets that reflect sunlight away from the earth’s surface, Munoz says.

“That effect is actually a cooling effect,” he says. “If it’s a really big eruption, that cooling effect can last for a year,” Munoz says.

“They create clouds where there would not otherwise have been clouds,” Douglass says.

But it is a genie many scientists say should remain in the test tube bottle.

For one, sulfur dioxide “is the same stuff that causes acid rain,” Douglass says.

And secondly, “there’s some climate modeling that suggests that (the exercise) might decrease the amount of rains that come to India during the monsoon season,” which could impact crop productivity, he says.

“There’s this kind of geopolitical question that would come up about control of that—who puts their finger on the thermostat, essentially,” says Munoz, an assistant professor and expert in hydrology.

Plus, the cooling effect doesn’t last long, he says. “The moment you stop emitting sulfur dioxide, the climate will very quickly warm.”

Volcanoes do contribute some carbon dioxide into the atmosphere, but there would have to be a lot of tectonic activity to even come close to greenhouse gas levels emitted by human activity, Munoz says.

Think back to 70 million years ago, when dinosaurs roamed the Earth and “there was a lot of volcanism,” he says.

But what about climate change’s impact on volcanoes?

A research paper published in 2013 raised the issue of whether glacial melt was contributing to volcanic activity in Iceland.

“The thought process is that if you melt all the glaciers of Iceland, that would decrease pressure” on rocks being brought to the surface from deep inside the earth, Douglass says.

“As they get into shallower depths, the pressure on the material goes down and (that) allows the rocks to melt and turn into magma,” he says.

“I don’t think the glaciers are melting that fast,” Douglass says. “It may cause a minor increase in volcanic eruptions, but I can’t imagine that’s going to be a big driver.”

As far as Mauna Loa is concerned, it’s not the type of volcano that causes massive, nuclear-like explosions with towering mushroom clouds that send materials into the stratosphere, potentially creating cooling, umbrella-like effects, Douglass and Munoz say.

The Hawaiian volcano’s activity has affected climate change in one way, by disrupting key equipment used to measure carbon dioxide levels in the atmosphere, according to media sites such as CNN.

But its eruption for the first time in 38 years is in essence an Earth-building, not atmosphere-impacting, event, Munoz and Douglass say.

Mauna Loa is a lava-oozing shield volcano, Munoz says. “I tell students (shield volcanoes) don’t go boom. They’re pretty cool to watch, though.’

This article originally appeared on [email protected]

Photo by AP Photo/Gregory Bull

December 02, 2022

No events found.

More Questions? Contact our Academic Departments