Posts tagged neuroscience
Articles and news from the latest research reports.
Fighting disease deep inside the brain
Some 90,000 patients per year are treated for Parkinson’s disease, a number that is expected to rise by 25 percent annually. Deep Brain Stimulation (DBS), which consists of electrically stimulating the central or peripheral nervous system, is currently standard practice for treating Parkinson’s, but it can involve long, expensive surgeries with dramatic side effects. Miniature, ultra-flexible electrodes developed in Switzerland, however, could be the answer to more successful treatment for this and a host of other health issues.
Today, Professor Philippe Renaud of the École Polytechnique Fédérale de Lausanne (EPFL) in Switzerland reports on soft arrays of miniature electrodes developed in his Microsystems Laboratory that open new possibilities for more accurate and local DBS. At the 2013 Annual Meeting of the American Association for the Advancement of Science (AAAS) in Boston, in a symposium called “Engineering the Nervous System: Solutions to Restore Sight, Hearing, and Mobility,” he announces the start of clinical trials and early, yet promising results in patients, and describes new developments in ultra-flexible electronics that can conform to the contours of the brainstem—in the brain itself—for treating other disorders.
At AAAS, Renaud outlines the technology behind these novel electronic interfaces with the nervous system, the associated challenges, and their immense potential to enhance DBS and treat disease, even how ultra flexible electronics could lead to the auditory implants of the future and the restoration of hearing. “Although Deep Brain Stimulation has been used for the past two decades, we see little progress in its clinical outcomes,” Renaud says. “Microelectrodes have the potential to open new therapeutic routes, with more efficiency and fewer side effects through a much better and finer control of electrical activation zones.” The preliminary clinical trials related to this research are being done in conjunction with EPFL spin-off company Aleva Neurotherapeutics, the first company in the world to introduce microelectrodes in Deep Brain Stimulation leading to more precise directional stimulation.
Shedding New Light on Infant Brain Development
A new study by Columbia Engineering researchers finds that the infant brain does not control its blood flow in the same way as the adult brain. The findings, which the scientists say could change the way researchers study brain development in infants and children, are published in the February 18 Early Online edition of Proceedings of the National Academy of Sciences (PNAS).
“The control of blood flow in the brain is very important,” says Elizabeth Hillman, associate professor of biomedical engineering and of radiology, who led the research study in her Laboratory for Functional Optical Imaging at Columbia. “Not only are regionally specific increases in blood flow necessary for normal brain function, but these blood-flow increases form the basis of signals measured in fMRI, a critical imaging tool used widely in adults and children to assess brain function. Many prior fMRI studies have overlooked the possibility that the infant brain controls blood flow differently.”
“Our results are fascinating,” says Mariel Kozberg, a neurobiology MD-PhD candidate who works under Hillman and is the lead author of the PNAS paper. “We found that the immature brain does not generate localized blood-flow increases in response to stimuli. By tracking changes in blood-flow control with increasing age, we observed the brain gradually developing its ability to increase local blood flow and, by adulthood, generate a large blood-flow response.”
The study results suggest that fMRI experiments in infants and children should be carefully designed to ensure that maturation of blood-flow control can be delineated from changes in neuronal development. “On the other hand,” says Hillman, “our findings also suggest that vascular development may be an important new factor to consider in normal and abnormal brain development, so our findings could represent new markers of normal and abnormal brain development that could potentially be related to a range of neurological or even psychological conditions.”
Brain plasticity
Babies’ brains are highly plastic, meaning they’re constantly adapting as they learn and respond to the world and people around them.
Daphne Maurer, director of the Visual Development Laboratory at McMaster University in Hamilton, Ontario, has found clues as to when plasticity might be locked off in babies and how in some adults it actually may persist unbeknown to them.
Scans reveal intricate brain wiring
Scientists are set to release the first batch of data from a project designed to create the first map of the human brain.
The project could help shed light on why some people are naturally scientific, musical or artistic.
Some of the first images were shown at the American Association for the Advancement of Science meeting in Boston.
I found out how researchers are developing new brain imaging techniques for the project by having my own brain scanned.
Scientists at Massachusetts General Hospital are pushing brain imaging to its limit using a purpose built scanner. It is one of the most powerful scanners in the world.
The scanner’s magnets need 22MW of electricity - enough to power a nuclear submarine.
The researchers invited me to have my brain scanned. I was asked if I wanted “the 10-minute job or the 45-minute ‘full monty’” which would give one of the most detailed scans of the brain ever carried out. Only 50 such scans have ever been done.
I went for the full monty.
It was a pleasant experience enclosed in the scanner’s vast twin magnets. Powerful and rapidly changing magnetic fields were looking to see tiny particles of water travelling along the larger nerve fibres.
By following the droplets, the scientists in the adjoining cubicle are able to trace the major connections within my brain.
Obama Seeking to Boost Study of Human Brain
The Obama administration is planning a decade-long scientific effort to examine the workings of the human brain and build a comprehensive map of its activity, seeking to do for the brain what the Human Genome Project did for .
The project, which the administration has been looking to unveil as early as March, will include federal agencies, private foundations and teams of neuroscientists and nanoscientists in a concerted effort to advance the knowledge of the brain’s billions of neurons and gain greater insights into perception, actions and, ultimately, consciousness.
Scientists with the highest hopes for the project also see it as a way to develop the technology essential to understanding diseases like and , as well as to find new therapies for a variety of mental illnesses.
Moreover, the project holds the potential of paving the way for advances in artificial intelligence.
The project, which could ultimately cost billions of dollars, is expected to be part of the president’s budget proposal next month. And, four scientists and representatives of research institutions said they had participated in planning for what is being called the Brain Activity Map project.
The details are not final, and it is not clear how much federal money would be proposed or approved for the project in a time of fiscal constraint or how far the research would be able to get without significant federal financing.
In his State of the Union address, cited brain research as an example of how the government should “invest in the best ideas.”
“Every dollar we invested to map the human genome returned $140 to our economy — every dollar,” he said. “Today our scientists are mapping the human brain to unlock the answers to Alzheimer’s. They’re developing drugs to regenerate damaged organs, devising new materials to make batteries 10 times more powerful. Now is not the time to gut these job-creating investments in science and innovation.”
A sensational breakthrough: the first bionic hand that can feel
The first bionic hand that allows an amputee to feel what they are touching will be transplanted later this year in a pioneering operation that could introduce a new generation of artificial limbs with sensory perception.
The patient is an unnamed man in his 20s living in Rome who lost the lower part of his arm following an accident, said Silvestro Micera of the Ecole Polytechnique Federale de Lausanne in Switzerland.
The wiring of his new bionic hand will be connected to the patient’s nervous system with the hope that the man will be able to control the movements of the hand as well as receiving touch signals from the hand’s skin sensors.
Dr Micera said that the hand will be attached directly to the patient’s nervous system via electrodes clipped onto two of the arm’s main nerves, the median and the ulnar nerves.
This should allow the man to control the hand by his thoughts, as well as receiving sensory signals to his brain from the hand’s sensors. It will effectively provide a fast, bidirectional flow of information between the man’s nervous system and the prosthetic hand.
“This is real progress, real hope for amputees. It will be the first prosthetic that will provide real-time sensory feedback for grasping,” Dr Micera said.
“It is clear that the more sensory feeling an amputee has, the more likely you will get full acceptance of that limb,” he told the American Association for the Advancement of Science meeting in Boston.
“We could be on the cusp of providing new and more effective clinical solutions to amputees in the next year,” he said.
Nano-machines for “Bionic Proteins”
Physicists of the University of Vienna together with researchers from the University of Natural Resources and Life Sciences Vienna developed nano-machines which recreate principal activities of proteins. They present the first versatile and modular example of a fully artificial protein-mimetic model system, thanks to the Vienna Scientific Cluster (VSC), a high performance computing infrastructure. These “bionic proteins” could play an important role in innovating pharmaceutical research. The results have now been published in the renowned journal “Physical Review Letters”.
Proteins are the fundamental building blocks of all living organism we currently know. Because of the large number and complexity of bio-molecular processes they are capable of, proteins are often referred to as “molecular machines”. Take for instance the proteins in your muscles: At each contraction stimulated by the brain, an uncountable number of proteins change their structures to create the collective motion of the contraction. This extraordinary process is performed by molecules which have a size of only about a nanometer, a billionth of a meter. Muscle contraction is just one of the numerous activities of proteins: There are proteins that transport cargo in the cells, proteins that construct other proteins, there are even cages in which proteins that “mis-behave” can be trapped for correction, and the list goes on and on. “Imitating these astonishing bio-mechanical properties of proteins and transferring them to a fully artificial system is our long term objective”, says Ivan Coluzza from the Faculty of Physics of the University of Vienna, who works on this project together with colleagues of the University of Natural Resources and Life Sciences Vienna.
Simulations thanks to Vienna Scientific Cluster (VSC)
In a recent paper in Physical Review Letters, the team presented the first example of a fully artificial bio-mimetic model system capable of spontaneously self-knotting into a target structure. Using computer simulations, they reverse engineered proteins by focusing on the key elements that give them the ability to execute the program written in the genetic code. The computationally very intensive simulations have been made possible by access to the powerful Vienna Scientific Cluster (VSC), a high performance computing infrastructure operated jointly by the University of Vienna, the Vienna University of Technology and the University of Natural Resources and Life Sciences Vienna.
Artificial proteins in the laboratory
The team now works on realizing such artificial proteins in the laboratory using specially functionalized nanoparticles. The particles will then be connected into chains following the sequence determined by the computer simulations, such that the artificial proteins fold into the desired shapes. Such knotted nanostructures could be used as new stable drug delivery vehicles and as enzyme-like, but more stable, catalysts.
Blind brain receives “visual” cues for identifying object shape
A significant number of blind humans, not unlike bats and dolphins, can localize silent objects in their environment simply by making clicking sounds with their mouth and listening to the returning echoes. Some of these individuals have honed this skill to such a degree that they are not only able to localize an object, they are able to recognize the object’s size and shape – and even identify the material it is made from.
Researchers at Western University’s Brain and Mind Institute (BMI) used functional magnetic resonance imaging (fMRI) to study the brain of renowned blind echolocator Daniel Kish as he listened to recordings of his own mouth clicks and the echoes reflected back from different objects.
The results of this study, which was carried out in collaboration with colleagues based in Durham University in the U.K., the Rotman Research Institute at the Baycrest Hospital in Toronto, and World Access for the Blind, a not-for-profit organization based in California, appeared this week in the journal Neuropsychologia. In keeping with the previous research from this group, the researchers found that areas in Kish’s brain that were activated by the echoes corresponded to visual areas in the sighted brain.
But what has senior author and BMI Director Mel Goodale most excited about the new findings is that the particular areas in Kish’s brain that extract echo-based information about object shape are located in exactly the same brain regions that are activated by visual shape cues in the sighted brain.
"This work is shedding new light on just how plastic the human brain really is," says Goodale.
Lead author Stephen Arnott of Baycrest’s Rotman Research Institute explains, “This study implies that the processing of echoes for object shape in the blind brain can take advantage of the brain’s predisposition to process particular object features, such as shape, in particular brain regions – even though the sensory system conveying that information is very different.”
Kish lost both his eyes to cancer when he was only one-year old and taught himself to echolocate when he was a toddler. Interestingly, two other blind individuals who learned to echolocate much later in life do not show nearly the same level of brain activation in these ‘visual’ object areas as Kish.
(Source: communications.uwo.ca)
Can Boosting Immunity Make You Smarter?
After spending a few days in bed with the flu, you may have felt a bit stupid. It is a common sensation, that your sickness is slowing down your brain. At first blush, though, it doesn’t make much sense. For one thing, flu viruses infect the lining of the airways, not the neurons in our brains. For another, the brain is walled off from the rest of the body by a series of microscopic defenses collectively known as the blood-brain barrier. It blocks most viruses and bacteria while allowing essential molecules like glucose to slip through. What ails the body, in other words, shouldn’t interfere with our thinking.
But over the past decade, Jonathan Kipnis, a neuroimmunologist in the University of Virginia School of Medicine’s department of neuroscience, has discovered a possible link, a modern twist on the age-old notion of the body-mind connection. His research suggests that the immune system engages the brain in an intricate dialogue that can influence our thought processes, coaxing our brains to work at their best.
When good habits go bad: Neuroscientist seeks roots of obsessive behavior, motion disorders
Learning, memory and habits are encoded in the strength of connections between neurons in the brain, the synapses. These connections aren’t meant to be fixed, they’re changeable, or plastic.
Duke University neurologist and neuroscientist Nicole Calakos studies what happens when those connections aren’t as adaptable as they should be in the basal ganglia, the brain’s “command center” for turning information into actions.
"The basal ganglia is the part of the brain that drives the car when you’re not thinking too hard about it," Calakos said. It’s also the part of the brain where neuroscientists are looking for the roots of obsessive-compulsive disorder, Huntington’s, Parkinson’s, and aspects of autism spectrum disorders.
In her most recent work, which she’ll discuss Saturday morning, Feb. 16 at the American Association for the Advancement of Science annual meeting in Boston, Calakos is mapping the defects in circuitry of the basal ganglia that underlie compulsive behavior. She is studying mice that have a synaptic defect that manifests itself as something like obsessive-compulsive behavior.
Calakos’ former colleague Guoping Feng developed the mice at Duke before moving to the McGovern Institute for Brain Research at MIT, where he now works. Feng was exploring the construction of synapses by knocking out genes one at a time. One set of mice ended up with facial lesions from endlessly grooming themselves until their faces were rubbed raw. When examining synaptic activity in the basal ganglia of these mice, Calakos’ group discovered that metabotropic glutamate receptors, or mGluRs, were overactive and this in turn, left their synapses less able to change. Scientists think overactivity of these receptors can cause many aspects of the autistic spectrum disorder Fragile X mental retardation.
"It’s an example of synaptic plasticity going awry," Calakos said. "They’re stuck with less adaptable synapses." Calakos is now using the mice to determine whether drugs that inhibit mGluRs can be used to improve their behavior and testing whether the circuit defects are a generalizable explanation for similar behaviors in other mouse models. This work may then lead to new understandings for compulsive behaviors and new treatment opportunities.
(Source: medicalxpress.com)