The brain is the most complex organ in the human body. It makes up two percent of a body’s mass yet uses 20 percent of its blood and oxygen supplies. It controls the way we think. It controls our movements. It dictates the way we make decisions. And it determines how we recall memories. It is powerful yet fragile.
FIU scientists from across the disciplines — medicine, engineering, arts and sciences — have dedicated their careers to studying mental processes in the healthy and the diseased human brain. They study brain activity, including language, cognition, emotion, action, sensory perception and mental health, while working to develop new technologies in cognitive neuroimaging.
Understanding how the pathways within the brain work to enable the functionality of its connections—electrical, anatomical and physiological — has long eluded us, in part because they could not be easily seen or observed. Until now.
“There’s been an incredible explosion in scientific data that allows us to understand the brain better as genetics, research, physics, imaging and cognitive research have all collided to present an unprecedented opportunity of multimodality and multidisciplinary research,” says Sergio Gonzalez-Arias, M.D., Ph.D., chairman of the Department of Neuroscience at the Herbert Wertheim College of Medicine. “Our ability to deliver a multidisciplinary environment for research and integrative research allows us to participate in much more relevant research and shortened path to clinical trials and then to treatment.”
Collaboration is making possible advances unheard of just a few years ago. “We at FIU have an incredible group of well-respected and renowned neuroscience researchers coming together, and this provides endless opportunities in today’s research world,” Gonzalez-Arias says. And, he adds, FIU’s location in culturally diverse South Florida further enhances its capacity to contribute to the field. “There are very few regions that have the ability to study one or more different demographics from so many different aspects — cultural, social determinants and early interventions.”
FIU’s strength in neuroscience has not happened by chance. “Our university leadership has put us in an enviable position with our strategic hires and our community partnerships. The first half of the 21st century will result in so much more knowledge about the brain than was discovered in the last half of the 20th century.”
A snapshot of cognitive learning
When Angela Laird, director of the Cognitive Neuroscience and Imaging Center, arrived at FIU, she was presented with something she had not seen in more than a decade: introductory physics students that she was expected to teach. Most recently engaged in intensive biomedical research, she decided to find a way to both teach and undertake a study on the young people in her classes at the same time.
“I solved problems with them and I worked with them all semester long and I watched their brains do this magnificent thing where they would struggle and struggle and struggle and get mad at me and then all of a sudden the light bulb would come on and they would get it and they were overjoyed,” Laird says. “And I said, ‘This is fascinating from a brain perspective.’”
A cognitive neuroscientist with a physics background, Laird began imaging students’ brains before and after they took the course to see how undergraduate STEM majors develop critical thinking skills. She had students complete a computer-based multiple-choice task while she and her team studied what the brain was doing.
“When they first start this course,” Laird explained, “these students activate the fronto-parietal network to solve a problem. After the course, they still require the fronto-parietal network.” So while it appeared that nothing had changed, the researchers found something interesting upon looking more closely: One area in the back center of the brain was more active in the post-class students. Oddly, that region, known as the default node network, is commonly associated with non-goal behavior and a resting state.
That prompted a hypothesis: Could this region also be activated when the brain is integrating a lot of information and putting together everything that has been learned within a specific context?
The study results will assist not only those who teach budding scientists and engineers, it may also help clinicians identify the sources of disruption in functional brain networks that lead to conditions like depression, schizophrenia and autism.
Understanding language acquisition
Children develop language first by learning the speech sounds of their native tongue. In a surprisingly short time they begin to understand speech, and a short time later they produce words and combine them to form sentences. All of this takes place in the context of other kinds of communicative information, which forms the foundation for developing speech, language and literacy.
Although we know a lot about the trajectory of this development, we know a lot less about how the young brain acquires these uniquely human abilities, and how these abilities are impaired in the brain in disordered populations. Anthony Dick, an assistant professor of psychology and director of the Cognitive Neuroscience Program, conducts leading research to answer these questions.
His work focuses on the fiber pathways that support speech, language and literacy and how these are affected by various developmental disorders, such as ADHD, or nutritional deficits such as iron deficiency.
“Medical science desperately needs new models and theories of how the brain functions to support higher-level cognition. With the advent of new methodologies such as functional magnetic resonance imaging and diffusion-weighted imaging, we can now explore how the brain functions in living people,” he says. Dick’s research uses these approaches to see how the living brain accomplishes a variety of tasks, with a focus on language and literacy. And in the case of the developing brain, he emphasizes the importance of early intervention in treating a variety of disorders such as pathology, ADHD and autism. “The availability of novel neuroimaging techniques gives researchers unprecedented opportunities to design focused interventions to take advantage of that early window of intervention.”
The addicted brain
Assistant professor of psychology Matthew Sutherland’s work focuses on the impact of drug abuse on the human brain, specifically nicotine and marijuana.
With funding from the National Institute on Drug Abuse, Sutherland uses multiple neuroimaging tools to look at the function, structure and chemical composition of the “addicted brain.” Functional magnetic resonance imaging and electroencephalography helps him identify “brain signatures,” or unique patterns of brain activity. An understanding of such signatures could one day help researchers create personalized therapies for mental health conditions.
“When thinking about treatment decisions, it becomes important to understand the brain processes involved in order to provide precise targets for interventions, to identify the best intervention for a specific person and to determine if an intervention is working rather than just relying on a trial-and-error approach,” Sutherland says.
“A cardiologist can put someone on a treadmill and make treatment decisions based on the results of that cardiac stress test. Currently, we don’t have any similar brain-based signatures for addiction or other mental health conditions to inform treatment,” he explains. “And there’s no reason why we shouldn’t work towards that ultimate goal.”
Sutherland is part of a research team working on the multi-year national landmark study on substance use and adolescent brain development. The project will follow 10,000 children through adolescence, considered the developmental stage of highest risk for substance use and other mental health disorders. The goal is to inform prevention and treatment research priorities, public health strategies and policy decisions.
Consequences of toxic poisoning
During 30 years at Johns Hopkins University’s Bloomberg School of Public Health and five as chair of the Department of Environmental Health Sciences at Columbia University’s Mailman School of Public Health, Tomás R. Guilarte studied the effects of chronic, early-life exposure to lead on brain function and behavior.
Today, the new dean of the Robert Stempel College of Public Health & Social Work continues his work on the subject with more than $7.5 million in active grant funding around his specializations in neurotoxicology, neuroimaging and environmentally induced neurological diseases. He uses behavioral, cellular and molecular approaches to reveal the effects of heavy metal exposure on the developing brain, focusing specifically on the molecular mechanisms by which lead poisoning impairs cognitive function.
Childhood lead intoxication currently presents a significant public health problem, not only in the United States—where the Centers for Disease Control estimate more than four million U.S. households could be affected—but around the world. The recent stories of lead-tainted water in Flint, Mich., make clear that dangers persist even after decades of concerted efforts in this country to remove sources of the toxin, among them lead-based paints and leaded gasoline.
“Lead is still found in homes and other buildings around us, affecting the people who are exposed, especially children,” Guilarte said. “Lead exposure still needs to be addressed because it can affect children throughout their lives, with consequences for them, their families, our schools and our communities.”
And while it’s understood that childhood lead exposure results in cognitive function deficits, much less is known about the neurological and mental health consequences. Guilarte’s most recent studies indicate it could result in everything from lower IQ scores to schizophrenia in adolescence and adulthood.
High-tech tools for the neurologist
Malek Adjouadi, a professor of electrical and computer engineering and director of FIU’s Center for Advanced Technology and Education, and his team have created a number of tools to help physicians pinpoint damaged areas in the brain and optimize surgical outcomes.
To better understand and treat epilepsy, the researchers designed computer software that analyzes the data from electroencephalograms, or EEGs, which take electrical readings from several places along the skull. Much like a seismograph measures earthquake waves, the EEG detects the subtle “spike waves” in the brain that could guide the process for locating source of seizures, information that can be used for surgical planning or for MRI-guided therapeutic interventions. The software can both calculate from where the seizures are originating, based on the readings from several electrodes, and accurately trigger the MRI at the opportune time.
“When the detected spike happens, we trigger the MRI to take a picture of the brain in 3-D,” Adjouadi says. “So now we have two modalities telling us exactly the same location that is causing the seizure, and doctors are reassured that the action they will take in surgery is the correct one,” he says. The same protocol holds promise for some patients presenting with depression.
Other collaborations in which Adjouadi is involved include examining ways to potentially stop or slow down the progression of Alzheimer’s Disease in its earliest manifestation through interventions using a transcranial magnetic stimulator. Acquired with the support of the National Science Foundation, the equipment, located in Adjouadi’s campus lab, is the first in the state and performs brain stimulation as a curative intervention for patients with various neurological disorders.
One of medicine’s most frustrating mysteries is why an ailing brain will rebuff the treatments meant to help it. The blood-brain barrier will allow some particles to pass through, but “The brain balks at attempts to deliver specific drugs,” says Sakhrat Khizroev, a physicist and electrical engineer who has dual appointments in the College of Engineering and Computing and the Herbert Wertheim College of Medicine. “It is absolutely incredible how the brain seems to understand and to quickly develop multidrug resistance.”
So in 2011, Khizroev helped create a new, non-invasive technology that uses magneto-electric nanoparticles, or MENs, that are able to march through the blood-brain membrane to direct therapies to specific targets.
MENs also enable unprecedented imaging of neural activity in the brain in real time. The brain, notes Khizroev, is essentially a wireless network with 80 billion neurons. “We can go deep inside to pick up those wireless signals.”
In a study that was named one of the 2015 “Top Science Stories of the Year,” Khizroev’s team did just that. They used MENs to wirelessly stimulate selective regions in the brains of mice. The nanoparticles were used to “read” electric fields at a sub-neuronal level, explains Khizroev, who adds that the breakthrough “paves a way to reverse-engineer the brain.” It also has the potential to treat neurodegenerative diseases such as Parkinson’s and Alzheimer’s.
In addition to collaborating with colleagues in the medical school such as Dr. Carolyn Runowicz and fellow engineers, Khizroev is working closely with Dr. Andrew Schally, the Nobel Prize-winning director of The Endocrine, Polypeptide and Cancer Institute, to deliver cancer-fighting peptides to currently incurable gliobastoma tumors in the brain, a pinpoint treatment that minimizes collateral damage to healthy cells. ♦
Hungry for more “brain food”? Click here to read about other brain research being done at FIU.