Category: Lecture Page 18 of 20

Probing our Internal Universe

On March 20, 2012

In Animals, Biomedical Engineering, Lecture, Neuroscience

By Prachiti Dalvi

Dr. Nicolelis was recently featured on the Daily Show with Jon Stewart to discuss his new book: Beyond Boundaries.

At the 2014 FIFA World Cup, Dr. Miguel Nicolelis hopes to see a quadriplegic child walk into the pitch and deliver the kickoff of the opening game. A pioneer in brain machine interface research and recent author of Beyond Boundaries, Nicolelis gave an evening talk on March 14 at the Nasher as a part of Brain Awareness Week. Dr. Nicolelis grew up in São Paulo and came to Duke in 1993. Since then, he has focused his research efforts on facilitating two-way dialogue between brains and machines.

Recent advancements in biomedical engineering allow us to use filaments implanted in several parts of the brain to obtain brain function readings: something that was impossible several decades ago. In one of Dr. Nicolelis’s first experiments, monkeys learned to use a joystick to catch a moving object on a screen. After the monkey was able to accurately catch the object 90% of the time, a brain-machine interface was turned on linking the robotic arm to the brain signals. The joystick was eliminated from the setup. The only way to obtain the reward (Brazilian orange juice) was to imagine catching the object.

The brain-machine interface allows for the translation of mental movements into digital commands while recording muscle activity. Using data collected from this experiment, on March 28, 2003, the Nicolelis team was able to design and operate the first robotic arm.

Until recently, neurons were considered the basic functional unit of the brain. More recently, scientists have focused their attention on populations of neurons as functional units instead.

Nicolelis and others are focusing on cell assembles as key functioning units of the brain, not simply neurons. “Populations of neurons across multiple brain structures are working together to make movement possible,” says Nicolelis. Thus, a holistic approach of looking at brain activation is necessary to understand and replicate movement in machines. Differences in the number of neurons activated have been observed when neurons are operating a robotic arm instead of a biological arm.

In a second set of studies, Nicolelis studied the effect of virtual simulations on the brain’s ability to assimilate other things as extensions of the human body. For example, if a professional tennis player is blindfolded and asked to point where his/her arm ends quickly after they have been playing tennis for an hour or so, they will point to the end of the racket as the end of the arm. In other words, the tennis player is assimilating the racket as an extension of the body. Similarly, if a monkey sees a knife approaching a rubber limb that is in the place where his arm should be, he will experience the anxiety, increase in heart rate, and even remove his real arm away from the perceived source of danger.

In an international collaboration with a team from Kyoto, Japan, researchers were able to send brain activity data of a monkey walking on a treadmill to a robot in Japan. The video of the robot walking was then transmitted back to the monkey. Even when the treadmill was stopped, and the monkey was rewarded for each step the robot took, the monkey began imagining that she was the one taking steps in order to be rewarded.

This brain-machine interface research has interesting implications in medicine, ranging from spinal lesions to Parkinson’s disease. When a spinal lesion forms, the brain continues to produce brainstorms to direct movement; however, the body does not have access to muscles. This is where the brain-machine interface comes into play: the brain can provide the directions that can be converted to digital commands, which can ultimately lead to functioning of the machine. To use the brain-machine interface to treat Parkinson’s, Dr. Nicolelis has been using a mouse model developed by Dr. Marc Caron in which 80% of the neurotransmitter dopamine is depleted. The rigid movements of Parkinson’s patients can be refined using brain-machine interface technology.

The brain-machine interface has the ability to alter medicine tremendously.

Dr. Nicolelis’s research implies that it is “possible to use brain activity beyond epithelial boundaries we have,” he says. Perhaps we will be able to do things using this technology, which we customarily cannot do because of the physical constraints of our body because there is no limit to what our minds are capable of doing. “There is a tremendous range of opportunities in this field.”

With the progress the Nicolelis lab is making, perhaps we will be able to see something truly unique at the 2014 FIFA World Cup in Brazil!

Animal emotions may mirror our own

By Becca Bayham

On March 19, 2012

In Animals, Behavior/Psychology, Lecture, Neuroscience, Science Communication & Education

Photo by Becky Phillips, WSU

By Becca Bayham

Did you know that rats can laugh?

All you have to do is tickle them. Oh, and get a supersonic noise detector so that you can hear their happy chirps. [Click here for video]

“It’s one of the most remarkable phenomena I’ve seen in my life,” renowned researcher Jaak Panksepp said during a lecture at Duke, March 15. Panksepp spoke as part of Brain Awareness Week, a series of events dedicated to increasing public awareness about brain research.

Panksepp is well-known for his work in the field of affective neuroscience, or the study of the neural mechanisms that underlie emotion. He argues that important inferences about human emotions can be made from studying emotion in animals. However, this idea has met resistance in the neuroscience community.

“Most scientists are skeptical that animal feelings can ever be studied,” Panksepp said. At this, he gestured toward the audience.

“Well, I will never know what any of you feel, nor will you ever know what I feel,” he said. “But do we close discussion on this important topic, or do we try to work past it?”

Panksepp considers the idea worth investigating, and he has conducted many experiments to test the relationship between human and animal emotions. For example, he found that rats exposed to cat hair exhibited signs of fear, even when they’d never seen a cat before.

“I think you can identify a category of human feelings that correspond with animal feelings. There are going to be differences – there have to be … [But] if we understand their basic feelings, we will begin to understand our own.”

A Brain Food You Never Heard Of

By Karl Bates

On March 14, 2012

In Behavior/Psychology, Biology, Lecture, Neuroscience

Guest post by Sandra Ackerman, Duke Institute for Brain Sciences

Did you know that certain foods are good for your brain — especially if you can persuade your mom to eat them before you’re born?

Christina Williams, Ph.D.

In the second public lecture for Brain Awareness Week, this one given at the Duke Center for Living, Christina Williams, professor of psychology and neuroscience, made a strong case for the long-term benefits of good prenatal nutrition. Of course, all-around good nutrition is important for the health of both an expectant mother and her baby, but in her talk on Tuesday evening Williams focused on choline, “the essential nutrient you’ve probably never heard of.”

Choline is one of those innumerable B vitamins that rarely make it onto a nutrition label. But it deserves to become famous, because choline is important not only for the building of membranes and the proper working of the liver (both very useful in the human body) but also as a basis for the neurotransmitter acetylcholine—the chemical signal that lets us move our muscles. Oh, and it serves another purpose as well: acetylcholine is the main neurotransmitter used in the function of memory.

It is in the realm of memory that prenatal choline really shines. In extensive studies with rats at all stages of their lifespan, Williams and her colleagues have found that adding choline to the usual prenatal diet gives a major boost to the developing brain. As a result, the offspring have brains that not only prove more resilient to shock or trauma but also demonstrate healthy, high-functioning memory well into old age. In the hippocampus, the brain structure most responsible for memory, the prenatally-choline-supplemented rats even show an advantage in the proliferation of new neurons, which enable them to keep learning long after the normal rat retirement age (about 24 months).

A newborn infant, still tapped into her mother's bloodstream, for the moment. (Photo by Gengiskanhg via Wikimedia Commons)

All this is not to say that pregnant women should start gulping down choline, says Williams—least of all as a “supplement” purchased from a health store, because these non-drug compounds don’t undergo strict standardization and scrutiny from the FDA.

You may, however, want to beef up the choline in your regular diet, and in fact beef liver is one of the best dishes for this purpose. Tofu and other soy-based foods, legumes, eggs, and fish will also fill the bill. So lift high your fork, egg cup, or peanut butter-covered knife, and let us keep in mind the power of choline.

Catching the Space Bug

By Prachiti Dalvi

On March 13, 2012

In Biology, Biomedical Engineering, Lecture, Medicine, Nanotech

Prachiti Dalvi

Robert Satcher, MD, PhD –the first orthopedic oncologist to orbit the Earth –discussed his interest in telemedicine and telesurgery during a school of medicine seminar last month.

Growing up not to far from Duke in Denmark, South Carolina, Dr. Satcher developed a profound interest in science and chose to pursue chemical engineering at MIT. After graduating at the top of his class, he entered the MD/PhD program just across the river at Harvard Medical School and returned to MIT to complete his PhD in chemical engineering.

Then, he followed the more conventional route of interning in general surgery and spending his time as a resident at UCLA. Deciding to further specialize, Dr. Satcher proceeded with an orthopedic oncology fellowship at the University of Florida. For a short time period, Dr. Satcher was an assistant professor at Northwestern before he caught the space bug. Satcher successfully completed a rigorous application and interview process and was elected to begin space training at NASA.

Although his interests span chemical engineering and orthopedic oncology, he is particularly interested in bone mineralization, nanomaterials, and bone metastasis in cancer. At the MD Anderson Cancer Center he is exploring telesurgery and telemedicine. In November 2009, Dr. Satcher went into space as a mission specialist on Atlantis, spending more than 200 hours in space and engaging in more than twelve hours of spacewalk.

“Medical knowledge comes into play when people are going through adaptation in aerospace,” Satcher said. While in space, Satcher performed maintenance and conducted research on how the human body reacts in space. His own research interests resonated through when he was able to study how bone density and skeletal muscles are affected by zero gravity. Dr. Satcher likened walking in space while inspecting the station’s outside equipment to surgery: attention to precision is vital. To complete this task, he was able to use his surgical skills to navigate a robotic arm to scan the shuttle for damage.

Although space exploration comes with some dangers and difficulties, Satcher believes space exploration is important because there is a lot we still do not know. According to Dr. Robert Satcher, the common thread of curiosity for the unknown ties space exploration and medicine.

Neutrinos change their flavors, again

By Ashley Yeager

On March 8, 2012

In Lecture, Physics, Science Communication & Education

By Ashley Yeager

Two anti-neutrino detectors at Daya Bay, shown here prior to the pool being filled with ultrapure water. Courtesy of Roy Kaltschmidt, Lawrence Berkeley National Laboratory.

Elusive particles called neutrinos can change their flavors, just like the Wrigley Company trying out a new taste of Starburst candy.

Now, physicists say they have gotten the best glimpse yet of the most elusive change in neutrino flavors. The result is the “missing piece in the puzzle to understand the phenomenon of how the particles transform,” said University of Wisconsin-Madison physicist Karsten Heeger, a collaborator at the Daya Bay experiment.

He announced the new result at a symposium at Duke on March 8. The team has also submitted a paper on the result to Physical Review Letters.

Neutrinos are elementary particles that come in three flavors — muon, electron and tau. In past experiments, physicists have measured two of the ways that neutrinos can change flavors.

But no one had seen the third transformation yet. “It revealed itself in the disappearance of electron-flavored antineutrinos over a distance of only two kilometers at the Daya Bay experiment,” Heeger said. An anti-neutrino is the anti-matter counterpart of a neutrino.

By observing the change over short distances, the physicists have measured the “mixing angle,” called theta one-three. Measuring the angle will help them design new experiments to better understand why matter predominates over antimatter in the universe.

Last year, physicists at the T2K neutrino experiment in Japan said they had seen hints of neutrinos flipping flavors in a way to give them theta one-three. But the experiment was interrupted when Japan was hit by an earthquake and tsunami on March 11, 2011. Their results at that point did not have enough significance to constitute a discovery in particle physics.

In the new neutrino experiment, Heeger and his collaborators looked for anti-neutrinos coming from the six nuclear reactors at the Daya Bay Nuclear Power Plant in southern China. The team built and installed six anti-neutrino detectors in the mountains near the plant. Three of the detectors sit only about 500 meters from the plant, while the other three sit 1700 meters from it.

The nuclear reactors produced tens of thousands of electron antineutrinos. Recording the particles’ signals, the scientists found that the far detector registered six percent fewer electron-flavored particles. The deficit, according to Heeger and his collaborators, is the signal for the elusive neutrino flavor changes in neutrinos. He thinks there is less than a 1 in 3.5 million chance that the result happened by random chance.

Leading nuclear physicists to speak at Duke

By Ashley Yeager

On March 7, 2012

In Lecture, Physics, Science Communication & Education

By Ashley Yeager

Physics grad student Georgios Laskaris, left, and Haiyan Gao, the chair of Duke's physics department, right, work on an experiment to look for a new force of nature. Credit: Megan Morr, Duke Photography.

More than 20 years after Haiyan Gao began her work on the neutron, she is hosting the Symposium on Electroweak Nuclear Physics at Duke to celebrate Caltech physicist Robert McKeown’s influence on her and others in nuclear physics.

The event will also honor his achievements in the field and celebrate his sixtieth birthday. The conference will be held March 8-9 in the French Family Science Center. Click here for a full schedule of the talks. Physicist Steve Koonin will also give a public lecture on addressing the nation’s energy issues as part of the symposium.

Gao will present her latest research, describing how she and her collaborators are identifying the factors that cause a neutron to spin. Other leading scientists will present their research on protons, neutrinos, dark matter and more exotic particles, such as free quarks and dark photons.

You can read more about Gao’s work in Duke Today.

John Lennox: Christianity Gave Me My Subject

By Becca Bayham

On March 1, 2012

In Behavior/Psychology, Lecture, Science Communication & Education

By Becca Bayham

Is God relevant?

“The first question is to ask what, and to whom,” Dr. John Lennox said during a public lecture, Feb. 21.

Lennox, a professor of mathematics at Oxford University, regularly debates religion with the likes of Christopher Hitchens, Richard Dawkins, Michael Shermer and Peter Singer. His talk was presented by the Veritas Forum, an organization aimed at promoting dialogue between secular and religious perspectives.

“When I teach algebra at Oxford, I don’t mention God. He’s not relevant at that level of discourse. But how is it that there’s a universe for your equations? God might be relevant to that,” Lennox said.

Lennox contested the idea that science and religion are mutually exclusive, arguing that it stems from a false conception of God: “If I can’t explain it, then God did it.” Thus, the more science tells us about the world, the less room there is for God.

But God is not competing with science for an explanation, Lennox said.

“People think science is the only way to truth. If science was the only way to truth, you’d have to close half your faculties at Duke.”

He pointed to Duke’s own motto — erudito et religio — as an example of how religion shaped the development of modern universities — and modern science.

“I’m not remotely embarrassed to be a Christian and a scientist. In fact, it’s the other way around, because Christianity gave me my subject.”

Solving the world's humanitarian problems

By Becca Bayham

On February 15, 2012

In Business/Economics, Climate/Global Change, Computers/Technology, Engineering, Environment/Sustainability, Global Health, Lecture

By Becca Bayham

What will the world of 2050 look like?

Popular fiction tells us we’ll have hoverboards, spaceships and artificial intelligence. According to USAID advisor (and Duke alum) Alex Dehgan, we’ll also have new ways of addressing humanitarian challenges — and we’ll need them. Dehgan kicked off the Student International Discussion Group‘s Water & Energy Symposium, Feb. 10.

“We know that climate change is going to affect the U.S., the Middle East, Central Asia and North Africa. This is actually a national security issue for us,” Dehgan said. “One thing that I think has been forgotten is, it’s not just climate, it’s climate times the environment. It’s the interaction of these two pieces.”

Dehgan described a patch of tropical forest where all the trees had been cut down. Trees send moisture back to the atmosphere via transpiration. No trees, no rain. The ground dried up, and the area is now 30 degrees warmer than it was before.

The world of the future may look different in other ways. According to Dehgan, 51 countries will lose population between now and 2050, largely due to declining birth rates. Other countries such as India, Pakistan, Nigeria, Bangladesh, the Democratic Republic of the Congo, China, Uganda, Ethiopia and the U.S. will experience massive population growth. Some of those countries already face problems providing their people with sufficient food, energy and clean water.

“[USAID] sees the developing world as the future of the U.S. economy,” Dehgan said. “Many of these challenges aren’t just bad news. They’re challenges we can take on to develop our markets.”

To that end, Dehgan cited five trends that will help organizations tackle humanitarian challenges in the future:

Democratization of Science
It took researchers 13 years and 2.7 billion dollars to sequence a single human genome for the first time. Now a company can sequence 100 genomes a day for less than $100 each. Lower costs allow humanitarian groups to deploy innovative technologies (such as vaccines) on a large scale.
Increase in Computing Power
“The power of computing is increasing exponentially, while the cost is decreasing exponentially. This provides us with exceptional ability to use computer power to help understand and solve problems,” Dehgan said.
Data, Data, Data
“A kid in Africa has more power and knowledge in his hand with a smart phone than President Clinton had 15 years ago,” Dehgan said. Technologies such as remote sensing, crowd sourcing and bioinformatics will add new types of data to our pool of knowledge.
Connectivity
Cellphones act as gateways to human knowledge, providing people with access to information they didn’t have before.
Decentralization of Manufacturing
Certain 3D printers, for example, now have the ability to produce 70 percent of the parts needed for another 3D printer. Online course materials such as iTunesU and MIT OpenCourseWare help support individuals that are trying to solve their own problems.

Dehgan also says he hopes that a sort of “humanitarian X Prize” could identify solutions to our changing world by catalyzing new research.

In 1996, the X Prize Foundation announced a $10 million reward for the first group to launch a manned, reusable vehicle into space twice within two weeks. The foundation hoped to spur innovation that would make low-cost space flight possible, and they succeeded. The winning team claimed the prize in 2004, after investing $100 million in new technologies.

“With grants, you don’t know what you’re going to get,” Dehgan said. “If you have a prize, you only win the prize once you’ve actually solved the problem. And one of the great things about it is that you get more than one solution.”

Steve Koonin to speak March 8

By Ashley Yeager

On February 15, 2012

In Climate/Global Change, Lecture, News Release, Physics, Science Communication & Education

Official portrait of Steven E. Koonin, former Under-Secretary for Science of the United States Department of Energy. Credit: DOE.

Want to know what we should do to address America’s energy challenges?

Come hear the ideas of Steve Koonin, a former chief scientist at British Petroleum and more recently the Under Secretary for Science at the Department of Energy. He’ll speak at Duke at 5:15 p.m. on March 8, 2012. The lecture will be held in room 2231 of the French Family Science Center.

Koonin, an MIT-minted theoretical physicist and currently a researcher at the Institute for Defense Analyses in Washington D.C., will talk about strategies to incorporate alternative and renewable energy sources into our energy profile. The lecture is free and open to the public.

The talk is part of the university-hosted Symposium on Electroweak Nuclear Physics, a two-day science conference to explore the latest experiments and ideas on matter and how it behaves at ordinary temperatures — quite the opposite of what’s being studied at the Large Hadron Collider and other high-energy particle accelerators.

The symposium is being held in honor of Jefferson Lab deputy director for science R. D. McKeown’s sixtieth birthday.

Self-Injury as a Pathway to Relief

By Jeannie Chung

On February 10, 2012

In Behavior/Psychology, Lecture

By Jeannie Chung

The concept of pain usually reminds us of agony, scowls, and terror. Yet, to some, it is a pathway for relief and salvation.

Clinical Social Worker Carolyn O. Lee from Raleigh presented the subject of self-injury at the Psychiatry and Behavioral Sciences Grand Rounds at the Duke Hospital on Jan. 19. She provided a clear image of what motivates “cutting” and other self-injury, and who it may affect. She also suggested solutions.

Self-injury is counterintuitive to most, but a comfort to some. (iStock photo)

People who damage their body tissue to experience jolting pain receive a “natural high,” Lee said. These injuries are intentional and non-life threatening and occur generally in socially outcasted people. Cutting, self-burning, pin-sticking, scratching, and self –hitting, interference with wound healing, and bone breaking are the common methods used. The tools used for such actions are analogous to security blankets of young children, and are deemed very precious to the inflictor.

The most prevalent question is “Why?,” since the concept of self-injury goes against most people’s natural instinct for survival. People seek self-injury to cope, to regulate mood, affect, and consciousness, to relieve anxiety and depression, discharge anger, to inflict punishment, and induce pleasure, feel alive, and have a sense of control, Lee said. The injuries on their body are their voices, she said.

The general thought is “How will you know I am hurting if you cannot see my pain? I wear it on my body, and it shows what words cannot explain,” Lee said.

Before the self-abuse happens, the patient feels a sense of tension, worthlessness and anxiety. During the abuse, they may experience pleasure, exhilaration, relief and numbness. And afterwards they lapse into a pool of guilt, shame, disgust, sorrow, and intrigue, feeling out of control.

Self-abuse continues because it can differentiate inner and outer body boundaries or bring attentiveness to a mistreated body, Lee said. It may identify with the aggressor, displace rage, and regulate states of hyperarousal and dissociation.

Psychiatrists also suspect autism spectrum disorders or defects in theory-of-mind to be major factors for the emergence of such behavior. Physiologically, deficits in serotonin play a large part as well.

To treat self-abuse, Dr. Lee recommends a combination of psychoanalytic therapy and medication. She believes the relationship between the patient and the psychotherapist plays a significant role in mitigating the behavior. However, she added that if a patient shows signs of addictive behavior to self-injury, she would consider prescribing medications.