Sunday, October 9, 2011

Zinc ‘important for learning and memory’

ISLAMABAD: Researchers have been trying to pin down the role of zinc in the brain for more than 50 years, ever since scientists found high concentrations of the chemical in synaptic vesicles, a portion of the neuron that stores neurotransmitters.

Now, scientists at the University of Toronto Scarborough (UTSC), and colleagues at MIT and Duke University have found that zinc plays a key role in regulating how neurons communicate with one another, and could affect how memories form and how we learn.

Xiao-an Zhang, a chemistry professor at the University of Toronto Scarborough (UTSC), and colleagues at MIT and Duke University designed a chemical called ZX1 that would bind with zinc rapidly after it was released from the vesicles but before it could complete its journey across the synapse.

Using the chemical, they were able to observe how neurons behaved when deprived of zinc.

The researchers studied neurons in a brain region called the hippocampus, which is associated with learning and memory formation.

They found that removing zinc interfered with a process called long-term potentiation.

Long-term potentiation strengthens the connection between two neurons, and seems to be important for memory and learning.

The new research appears in the current issue of Neuron.

Paralyzed may have new hope

Monkeys use minds to move and sense objects around them.

Scientists believe they are a step closer to enabling paralyzed people to walk and use artificial arms after an experiment in which monkeys moved and sensed objects using only their minds.
The monkeys were able to operate a virtual arm to search for objects through brain activity that was picked up by implants - a so-called brain-machine interface.
In a leap forward from previous studies, the primates were also able to experience the sense of touch - a crucial element of any solution for paralyzed people because it enables them to judge the strength used to grasp and control objects.
"This was one of the most difficult steps and the fact that we achieved it opens the door to the dream of a person being able to walk again," Miguel Nicolelis, a Brazilian neuroscientist who took part in the study carried out by a team at Duke University in North Carolina.
The results suggest it would be possible to create a kind of robotic "exoskeleton" that people could use to feel and sense objects, he said.
"The success we've had with primates makes us believe that humans could perform the same tasks much more easily in the future," Nicolelis said.
The study was published in the journal Nature.
In the first part of the experiment, the rhesus monkeys were rewarded with food for using their hands to control a joystick in search of objects on a computer screen.
The joystick was then disconnected, leaving the monkeys to control the movement of a virtual arm on the screen through brain power alone.
Nicolelis told Reuters his goal is to use the technology to enable a young paraplegic athlete to take part in the opening ceremony of the 2014 soccer World Cup in Brazil.
From 2012, Nicolelis said the study will be taken over by Brazil and carried out at the Neuroscience Institute in the northeastern state of Natal.

Report Indicates an Increase in Concussion Awareness

Emergency room visits by children and adolescents for brain injuries jumped more than 60 percent over an eight-year period, according to a report released Thursday by the Centers for Disease Control and Prevention, which said the increase was believed to be a result of increased awareness of concussions and other head injuries.
The report said emergency rooms recorded an increase of visits from 153,375 in 2001 to 248,418 in 2009 among those 19 years old and younger because of traumatic brain injuries sustained in recreational activities. According to the study, the sports most likely to lead to the injuries are bicycling, football, playground activities, basketball and soccer.
“We believe that one reason for the increase in emergency department visits among children and adolescents may be a result of the growing awareness among parents and coaches, and the public as a whole, about the need for individuals with a suspected T.B.I. to be seen by a health care professional,” said Dr. Linda C. Degutis, director of the C.D.C.’s National Center for Injury Prevention and Control.
Concussions and their debilitating effects have been receiving increased attention, particularly in the N.F.L., which has taken steps to reduce the number of head injuries to players after years of distancing itself from research about the lasting impact of such injuries. The N.H.L. was also slow to adjust its rules to address the issue and was set to open its season Thursday with one of its best players, Sidney Crosby of Pittsburgh, sidelined because of the lasting effects of a concussion.
The issue has also become a flashpoint in youth sports. According to a recent report by the National Center for Catastrophic Sport Injury Research, more than 500,000 concussions are sustained by the 4.4 million children who play tackle football.
According to Dr. Julie Gilchrist, one of the C.D.C. study’s authors, the emergency room data is the first to quantify that the effort to educate coaches, parents and children about concussions is taking hold.
“We would like to see the numbers go down because we hope we have gotten better at preventing them, but we knew the numbers would have to go up before they start to come down because awareness has to go up first,” Gilchrist said.
Dr. Robert Cantu, co-director of Boston University’s Center for the Study of Traumatic Encephalopathy, also says the publicity surrounding concussions is having a significant impact. “I view the numbers as encouraging,” he said. “Some people will say that the numbers go up because the number of concussions is going up, but I don’t believe it is.”
Although Gilchrist said a rise in concussions is possible because even youth athletes are getting bigger and faster, she said that if that were the reason for the increase, the numbers of children admitted to the hospital for head injuries would also increase. But those numbers have remained relatively constant.
Still, Cantu said the biggest danger area is the amount of concussions that go undiagnosed, leading to potentially more debilitating and even fatal second-impact injuries. He said in football and hockey the number of actual concussions is six or seven times higher than the number diagnosed. Those numbers in hockey stem from research done in Canada in which physicians watched and counted the number of likely concussions sustained in games and practices in youth leagues.
It is why Cantu, who is writing a book about concussions at the youth level, believes children under 14 should not play collision sports until they are made safer.
“They should not play collision sports as they are currently played,” he said. “Listen, I love sports. I’m not trying to get rid of sports. I’m trying to get rid of head trauma in sports, particularly at the youth level.”
Collision sports were not at the root of all head injuries in the C.D.C. study. The report said that children under 10 are most likely to visit the emergency room for head injuries sustained on a playground or while bicycling. The injuries among males ages 10 to 19 are most likely from football, followed by bicycling. From ages 15 to 19, football causes by far the most concussions (30.3 percent). Soccer, basketball or bicycling are the most likely culprits for females ages 10 to 19.
Gilchrist said it was not possible to use the numbers to assess the risks of any particular activity because participation numbers are not part of the study. “Those activities may have the most concussions simply because they are so common,” she said.
She also said future research hoped to pin down head injuries that are treated by primary care physicians and other doctors, not just ones that land in emergency rooms, to get a better handle on just how many concussions are being sustained and how they are treated.
The C.D.C. has worked to increase awareness of the dangers of concussions with its Heads Up initiative, which began in 2003. It includes a section on its Web site dedicated to educating parents on the subject. It warns that even if an injury does not appear to be serious, it can have lasting repercussions, if left untreated, that affect memory, behavior, learning and emotional development.
And while the numbers signal progress, experts agree it is only a start.
“We are never going to get all of them, but we have to get a lot better,” Cantu said. “Not all the fault lies with the people on the sidelines. The kids have been to blame, too, playing through symptoms and not reporting. That’s why we have to educate them about the dangers of playing through them.”
Cantu said 32 states had passed legislation mandating concussion education for young athletes, parents and coaches.

Extracting brain cells through the nose could cure diabetes

Extracting brain cells through the nose could cure diabetes
Rats with both type 1 and type 2 diabetes have been completely cured of the disease, using neuronal stem cells that have been modified to produce insulin. This approach should work in humans, too, and all it involves is shoving a needle up your nose into your brain. Yay!
Stem cells are near-universally acknowledged to be the Next Big Thing in medicine, and the only reason that we haven't used them to cure every single disease already is that we can't all agree on a reasonable, ethical place to go get them from. But we've got stem cells all over the place in our own bodies, we just have to go and harvest them, which is easier said than done, but definitely not impossible.
Our brains, for example, are home to neural stem cells, which (with a little prodding) can transform themselves to perform all kinds of helpful tasks. One of these tasks is producing insulin, which researchers at the Institute of Advanced Industrial Science and Technology in Tsukuba Science City, Japan have shown can totally cure type 1 and type 2 diabetes, at least in rats.
To get the stem cells, the researchers stuck a needle up the noses of diabetic rats and poked around in their brains a little bit, extracting tissue from the olfactory bulb and the hippocampus, which are the parts of the brain that allow you to smell things and store memories, so poking them with a big needle is totally not a big deal.
The rat's brain tissue was chock-full of neural stem cells, which were extracted and taught to produce insulin using a human protein called Wnt3a. Then the cells were stuck onto thin sheets of collagen, which were implanted on top of the rat's pancreas, and within a week, the rat no longer had diabetes, as the stem cells were effectively able to produce insulin to regulate blood glucose levels. After 19 weeks, the stem cell sheets were removed, and the rats went straight back to being diabetic, with no other harmful effects.
Apparently, extracting neural stem cells from humans in this manner (i.e. with the needle up the nose) has already been tried and is completely safe, so all that remains is to verify that the neural stem cell insulin education technique works on human stems cell lines as well as in rats, and we could be looking at a permanent, drug-free cure for diabetes.

Most of brain reacts to winning, losing: study

New research from Yale University shows even more of your brain than previously thought physically reacts to something perceived as a win or a loss.

New research from Yale University shows even more of your brain than previously thought physically reacts to something perceived as a win or a loss.

A new National Hockey League season is upon us, Major League Baseball playoffs are in full swing and the National Football League's regular season has been in session for about a month.
As you fixate on your television, watching every move of your favourite athletes and longing for that great play or crucial win that can serve up a rush that can approach orgasm, consider this: New research from Yale University shows even more of your brain than previously thought physically reacts to something perceived as a win or a loss.
A new study, published in the journal Neuron, outlines experiments showing how most of the brain has heightened activity if one wins or loses a competition such as rock-paper-scissors.
It was a broader effect than what was known before to be a reaction of the central part of the brain in releasing dopamine when something good happens, creating a positive feeling in an individual. Conversely, past evidence has also shown this neurotransmitter is suppressed when an unwanted outcome occurs.
The study's lead author, Timothy Vickery, a post-doctoral fellow at Yale's psychology department, said it's possible that the brain has a similar kind of engagement when its owner is watching sports.
"We didn't look at that directly in this study, but it wouldn't be very surprising to me if those sorts of second-hand experiences had the same influence, because you're sort of identifying with your team, and a win for your team is a win for you," he said.
Vickery said the high engagement sports fans feel when watching a competition likely comes from the previously known function of the basal ganglia, in the middle of the brain, sending out dopamine when a positive outcome is perceived.
It has its roots, he said, in evolutionary tendencies that favour people and animals that are able to make the right choices to improve chances for survival and create results — such as finding food — that induce dopamine-fuelled feelings of joy.
Vickery said the effect can be vicarious when watching other people participate in sports.
"I think it's fair to say that, to the extent that you experience those wins and losses as your own, it would have a similar effect on your brain as taking your own actions," he said.
By conducting MRIs on people while they competed against a computer in games such as rock-paper-scissors, the Yale study found that most parts of subjects' brains, even beyond the basal ganglia, had physical reactions to both wins and losses.
By analyzing the brain as a whole, Vickery said the researchers could determine whether the individual was experiencing a win or a loss, based on subtle differences in the nature of the patterns. He said it is likely this broadly based brain reaction is somehow related to established theories concerning the reward-punishment function at the brain's centre. The study, however, could not conclude that.
"My suspicion is that it's not unrelated, that basically that signal gets sent out from the basal ganglia . . . and sort of filters out through the brain, but we don't know for sure where it's coming from. There's still a lot of work to be done."
Kim Dorsch, a sports psychology professor at the University of Regina, said in an email that "it makes total sense that the entire brain would be involved (in reacting to a win or loss).
"The release of the neurotransmitters is not the end of the story. The neurotransmitters definitely have an impact on our physiological reaction. However, there is a body of literature that suggests that once those chemicals are released into our body, then we engage in a process whereby we interpret those physiological sensations . . . These interpretations probably occur somewhere else in the brain."
Vickery added that practical implications from this research could include finding ways to incorporate the neurological rewards of a win to encourage greater workplace productivity or better learning outcomes in schools.

New Study Shows How Winning Affects The Brain

When we want to win all parts of the brain become engaged.
So says a Yale study published in the October 6 issue of Neuron, a journal that investigates genetics and the brain. It has reexamined the reward pathways of the brain that are conventionally associated with the basal ganglia, a center brain region responsible for decisions to act and dopamine which is thought to process rewarding and ineffective actions.
This brain study used a multi-voxel pattern analysis to analyze fMRI data to determine patterns in brain function throughout the brain rather than confining the data to the cerebral cortex. This study evaluated subjects playing either matching-pennies or rock-paper-scissors games to determine whether reward and punishment perceptions presented themselves in a particular part of the brain or whether there were other patterns at work.
The scientists discovered that when playing a game to win, the entire brain is active, not part of it. They also discovered that all parts of the brain showed patterns of response to reward and punishment.
"While it is likely that the basal ganglia and its projections are responsible for the core functions of reward-related processing, many other brain regions are at least provided with this information," concludes Dr. Timothy Vickery from the Department of Psychology at Yale and lead scientist on this study. "This suggests an imperative to study the effects of reinforcement and punishment in domains where they are not usually considered as important factors — from low-level sensory systems to high-level social reasoning. Such distributed representations would have adaptive value for optimizing many types of cognitive processes and behavior in the natural world."
What this means is not yet clear. We humans are continually engaging with our environment, and adapting to changes in it. Over time, our brain evolves strategies for dealing with successes and failures. However, the study demonstrates that our games and contests may hold greater implication for our identity and social functioning. This study seems to indicate that our brain, even in a competitive activity, operated holistically and that may suggest new ways to understand ourselves.