Founded by a mechanical engineer and historically known as the first American university to offer mechanical engineering as a degree, Stevens Institute of Technology has fostered researchers in the Department of Mechanical Engineering as they have devised solutions to industrial and mechanical problems in areas ranging from railroad transportation to manufacturing to robotics over the course of the school’s long history. This year, as the university approaches the 150th anniversary of its founding, a new research center is using its faculty’s expertise in the field to launch into a new arena: the study of mechanical engineering as it applies to the brain. Their multidisciplinary approach may prove groundbreaking in advancing our understanding of diverse topics ranging from concussions to Alzheimer’s disease.
Stevens Institute of Technology recently launched the Center for Neuromechanics, a first-of-its-kind facility in the U.S., to apply the fundamental principles of mechanics and engineering to understanding the function, structure, and health of the brain, spinal cord, and peripheral nervous system. Stevens assistant mechanical engineering professor Mehmet Kurt founded and serves as director of the center.
“Mechanics is the theory of how forces and deformations relate to each other, and it tries to represent and quantify those changes mathematically,” explained Stevens assistant professor of mechanical engineering Johannes Weickenmeier, a member of the center.
Antonia Zaferiou, assistant professor of biomedical engineering, offers an additional perspective. “Biomechanics is focused on understanding biological systems from a mechanical perspective, and investigating the relationship between structure and function of biological systems. Some biomechanists study things as small as individual cells, while others study whole organisms. The field incorporates prostheses, exoskeletons, sports performance, assistive devices, exercise, gaming, and so on. Therefore, it's a very diverse field that benefits from multidisciplinary perspectives and engagement. ”
The center is driven to better understand the role of mechanics in the brain and nervous system.
“There’s a lot of biological and chemical knowledge of the brain at very small scales such as the cell, but it takes mechanics to project what we know on that small, spatial level to the larger scales of tissues and organs,” Weickenmeier said. “We know that cells respond to forces, and that every cell takes on a special shape informed by its mechanical environment.”
This understanding can inform the study of the impact of traumatic brain injuries on a single brain cell, and the implications of shape changes during neurodegenerative diseases such as Alzheimer’s.
The Opportunities Are Endless
The members of the new Center for Neuromechanics are each approaching the study of the brain with their unique specializations and research experience.
Kurt’s fascination with the biomechanics of the brain, traumatic brain injury, and other areas of neuromechanics stems from his post-doctorate days at Stanford University.
“I’ve always wanted to research human health and help humans live better,” he said. “At Stanford, it struck me that mechanical principles could be useful in concussions and other traumatic brain injuries.” Because the brain is the softest organ in the human body, when it experiences a trauma, the resulting deformations and damage can be surprising.
“I wanted to understand how the brain responds to such external impacts,” Kurt said, “and how to reduce the damage with everything from better helmets, to better imaging to track the motion of the brain inside the skull, to better therapeutic strategies.”
He also sees significant potential in studying how natural changes to the brain are related to diseases such as Alzheimer’s, Parkinson’s, multiple sclerosis, and stroke.
“The human brain is a really dynamic material,” Kurt said. “From infancy, mechanics drives the cortical folding in the brain. As we age, microstructural changes happen that we’re learning can indicate developmental changes. As we improve our understanding of the mechanics of neural degeneration and the forces that guide those changes, we may be able to find ways to allow early diagnosis and prognosis of these life-altering conditions. The opportunities are endless.”
Using Mechanics to Benefit Healthcare
Faculty members have received nearly $4 million in grants from the National Science Foundation, National Institutes of Health, Department of Defense, and New Jersey Health Foundation to apply mechanical engineering principles to biomedical areas in four key areas:
Computational Biomechanics and Tissue Characterization
Through advanced research modeling and real-life experimentation, the center studies the mechanical behavior of the brain and neuronal tissue. Researchers are working with the Stevens soccer team and other athletes to understand the biomechanics of head movements and concussions, then conducting computational simulations of the brain to understand how it deforms, how an impact results in mechanical changes to the brain, and whether certain regions are more vulnerable to impact than others.
A widely accepted technique involves poking the brain to cause an indentation, and observing how the mechanical properties change. Because live human brains are not generally available for direct prodding, the team uses magnetic resonance of the brains of living humans, pigs, and sheep, as well as models of the brain, and samples from cadavers.
The team is also studying the accumulation of proteins and the resulting loss of brain volume.
“Computational biomechanics allows me to model and develop mathematical equations that model both how the proteins are spreading and how the brain is changing,” Weickenmeier said. “There’s such a wealth of data in medical imaging, and as an engineer, I can use engineering tools to help the medical community pinpoint changes between images to track changes over time.”
Weickenmeier believes that by offering those additional tools to discover and analyze data obtained through established imaging methods, the Center will be able to help transform how those methods are used—and also help transform people’s lives.
“Since people can live with dementia, Parkinson’s, and related diseases for a long time, the entire family that needs to support these people will inevitably be affected as well,” he said. “Finding indicators to support earlier diagnosis could potentially save a lot of money and, moreover, stress. If a patient knows he or she may be debilitated due to Parkinson’s disease, he or she can better advocate for themselves and make decisions about where to live and how to anticipate caregiving needs. It goes far beyond medicine into the whole social life. I’m proud that we’re using mechanics to benefit healthcare and a very large patient population.”
Currently funded projects include developing a system to characterize and model soft, hydrated materials such as brain tissue to support areas such as robotics design and health monitoring during surgery, and improving the measurement of the mechanical properties of living body tissues to more accurately measure the interfaces between tumors and normal tissue to detect small tumors sooner.
To better measure the motion and other mechanical properties of the brain in living humans, the team is developing imaging techniques to simplify diagnostics; improve understanding of neurodegenerative diseases; monitor recovery after traumatic events or degenerative pathologies; and reduce the time, cost, and risks associated with surgery.
One project underway involves using dynamic magnetic resonance imaging (MRI) techniques to investigate the structural cerebellum defects and brain motion associated with Chiari malformation I, a condition with symptoms ranging from recurrent headaches to paralysis. It’s challenging to diagnose, but early intervention and treatment can significantly improve clinical outcomes.
Biofabrication and Bionics
Biofabrication, at its simplest, means “making life.” Bionics, first brought to the public eye with the iconic Bionic Man of the 1970s, refers to the study of mechanical systems that function like living things. The Stevens Center for Neuromechanics is bringing both specialties to life, conjuring human tissue with state-of-the-art 3D printing techniques that combine molecular, cellular, and cognitive neurosciences and developmental neurobiology with electrical, mechanical, biomedical, and material sciences and engineering. The resulting models are helping increase understanding of neurosciences and nervous development, and supporting new treatments and rehabilitation strategies for people dealing with neurological disorders and disabilities.
“Mechanical engineering is traditionally interested in designing and building things,” said Stevens assistant professor of mechanical engineering Robert Chang. “In our lab, we’re designing and building novel 3D printing processes to consistently model nervous cells and tissues and their behavior to more closely mimic the body’s neural responses.”
One area Chang and his team are studying is the blood–brain barrier, a selectively permeable barrier to toxins and pharmaceuticals, for better understanding of how new drug offerings would penetrate not just anyone’s brain, but a specific individual’s brain. They are also collaborating with the Hackensack Medical Center to study placentas and model normal and disease systems.
“I appreciate that we’re not leveraging our core competencies in a vacuum,” Chang said, “but rather, we’re relying on and consulting with experts in biology as well.”
Through biomechatronics, the Center for Neuromechanics team is developing devices for patients dealing with neurological disorders, such as robotic exoskeletons to help rehabilitate stroke patients, as well as wearable devices to support diagnostic work. Other studies underway include using a mobile robot and smart insole sensors to help older adults live and socialize independently.
“Biomechatronics is an interdisciplinary area of research that brings together knowledge in biology, mechanics, and electronics to study wearable or implantable electromechanical systems for assistive, therapeutic, or diagnostic purposes,” said Damiano Zanotto, assistant professor of mechanical engineering. “For example, powered orthoses and exoskeletons can work as mobility aids for individuals with motor impairments, or augment traditional rehabilitation therapy programs for people who have suffered a neurological injury. Wearable biosensors can capture subtle motor behaviors that are imperceptible to the naked eye but may indicate underlying motor disturbances.”
Engineering the Best Possible Outcomes
The Center for Neuromechanics is also giving a voice to this emerging field of study.
The center’s team is advocating both within the Stevens community and among the broader public for the role of mechanics in understanding the brain. Because neuromechanics is interdisciplinary, the center will bring together complementary skill sets and areas of expertise to support a very advanced understanding of the brain.
“This is a highly emerging field, and to the best of our knowledge, Stevens is leading the way in bringing together faculty members from diverse disciplines to focus on the mechanics of the human brain,” said Kurt. “We approach our studies from multiple angles, from fabrication to development to imaging to mechanical characterization to computational models.”
“By looking into the human brain from these different perspectives, we’re bringing insights that have so far been underestimated,” he continued.“Through our collaboration with schools of medicine in the tristate area, we’re also bridging a gap and finding a common language between engineers and clinicians so that together, as scientists, we can have a direct impact on human lives. That’s what makes me excited about this center.”
The center will hold a launch event and reception on Monday, December 9.