Archive for the ‘brain computer interface’ Category

Wendy was barely 20 years old when she received a devastating diagnosis: juvenile amyotrophic lateral sclerosis (ALS), an aggressive neurodegenerative disorder that destroys motor neurons in the brain and the spinal cord.

Within half a year, Wendy was completely paralyzed. At 21 years old, she had to be artificially ventilated and fed through a tube placed into her stomach. Even more horrifyingly, as paralysis gradually swept through her body, Wendy realized that she was rapidly being robbed of ways to reach out to the world.

Initially, Wendy was able to communicate to her loved ones by moving her eyes. But as the disease progressed, even voluntary eye twitches were taken from her. In 2015, a mere three years after her diagnosis, Wendy completely lost the ability to communicate—she was utterly, irreversibly trapped inside her own mind.

Complete locked-in syndrome is the stuff of nightmares. Patients in this state remain fully conscious and cognitively sharp, but are unable to move or signal to the outside world that they’re mentally present. The consequences can be dire: when doctors mistake locked-in patients for comatose and decide to pull the plug, there’s nothing the patients can do to intervene.

Now, thanks to a new system developed by an international team of European researchers, Wendy and others like her may finally have a rudimentary link to the outside world. The system, a portable brain-machine interface, translates brain activity into simple yes or no answers to questions with around 70 percent accuracy.

That may not seem like enough, but the system represents the first sliver of hope that we may one day be able to reopen reliable communication channels with these patients.

Four people were tested in the study, with some locked-in for as long as seven years. In just 10 days, the patients were able to reliably use the system to finally tell their loved ones not to worry—they’re generally happy.

The results, though imperfect, came as “enormous relief” to their families, says study leader Dr. Niels Birbaumer at the University of Tübingen. The study was published this week in the journal PLOS Biology.

Breaking Through

Robbed of words and other routes of contact, locked-in patients have always turned to technology for communication.

Perhaps the most famous example is physicist Stephen Hawking, who became partially locked-in due to ALS. Hawking’s workaround is a speech synthesizer that he operates by twitching his cheek muscles. Jean-Dominique Bauby, an editor of the French fashion magazine Elle who became locked-in after a massive stroke, wrote an entire memoir by blinking his left eye to select letters from the alphabet.

Recently, the rapid development of brain-machine interfaces has given paralyzed patients increasing access to the world—not just the physical one, but also the digital universe.

These devices read brain waves directly through electrodes implanted into the patient’s brain, decode the pattern of activity, and correlate it to a command—say, move a computer cursor left or right on a screen. The technology is so reliable that paralyzed patients can even use an off-the-shelf tablet to Google things, using only the power of their minds.

But all of the above workarounds require one critical factor: the patient has to have control of at least one muscle—often, this is a cheek or an eyelid. People like Wendy who are completely locked-in are unable to control similar brain-machine interfaces. This is especially perplexing since these systems don’t require voluntary muscle movements, because they read directly from the mind.

The unexpected failure of brain-machine interfaces for completely locked-in patients has been a major stumbling block for the field. Although speculative, Birbaumer believes that it may be because over time, the brain becomes less efficient at transforming thoughts into actions.

“Anything you want, everything you wish does not occur. So what the brain learns is that intention has no sense anymore,” he says.


First Contact

In the new study, Birbaumer overhauled common brain-machine interface designs to get the brain back on board.

First off was how the system reads brain waves. Generally, this is done through EEG, which measures certain electrical activity patterns of the brain. Unfortunately, the usual solution was a no-go.

“We worked for more than 10 years with neuroelectric activity [EEG] without getting into contact with these completely paralyzed people,” says Birbaumer.

It may be because the electrodes have to be implanted to produce a more accurate readout, explains Birbaumer to Singularity Hub. But surgery comes with additional risks and expenses to the patients. In a somewhat desperate bid, the team turned their focus to a technique called functional near-infrared spectroscopy (fNIRS).

Like fMRI, fNIRS measures brain activity by measuring changes in blood flow through a specific brain region—generally speaking, more blood flow equals more activation. Unlike fMRI, which requires the patient to lie still in a gigantic magnet, fNIRS uses infrared light to measure blood flow. The light source is embedded into a swimming cap-like device that’s tightly worn around the patient’s head.

To train the system, the team started with facts about the world and personal questions that the patients can easily answer. Over the course of 10 days, the patients were repeatedly asked to respond yes or no to questions like “Paris is the capital of Germany” or “Your husband’s name is Joachim.” Throughout the entire training period, the researchers carefully monitored the patients’ alertness and concentration using EEG, to ensure that they were actually participating in the task at hand.

The answers were then used to train an algorithm that matched the responses to their respective brain activation patterns. Eventually, the algorithm was able to tell yes or no based on these patterns alone, at about 70 percent accuracy for a single trial.

“After 10 years [of trying], I felt relieved,” says Birbaumer. If the study can be replicated in more patients, we may finally have a way to restore useful communication with these patients, he added in a press release.

“The authors established communication with complete locked-in patients, which is rare and has not been demonstrated systematically before,” says Dr. Wolfgang Einhäuser-Treyer to Singularity Hub. Einhäuser-Treyer is a professor at Bielefeld University in Germany who had previously worked on measuring pupil response as a means of communication with locked-in patients and was not involved in this current study.

Generally Happy

With more training, the algorithm is expected to improve even further.

For now, researchers can average out mistakes by repeatedly asking a patient the same question multiple times. And even at an “acceptable” 70 percent accuracy rate, the system has already allowed locked-in patients to speak their minds—and somewhat endearingly, just like in real life, the answer may be rather unexpected.

One of the patients, a 61-year-old man, was asked whether his daughter should marry her boyfriend. The father said no a striking nine out of ten times—but the daughter went ahead anyway, much to her father’s consternation, which he was able to express with the help of his new brain-machine interface.

Perhaps the most heart-warming result from the study is that the patients were generally happy and content with their lives.

We were originally surprised, says Birbaumer. But on further thought, it made sense. These four patients had accepted ventilation to support their lives despite their condition.

“In a sense, they had already chosen to live,” says Birbaumer. “If we could make this technique widely clinically available, it could have a huge impact on the day-to-day lives of people with completely locked-in syndrome.”

For his next steps, the team hopes to extend the system beyond simple yes or no binary questions. Instead, they want to give patients access to the entire alphabet, thus allowing them to spell out words using their brain waves—something that’s already been done in partially locked-in patients but never before been possible for those completely locked-in.

“To me, this is a very impressive and important study,” says Einhäuser-Treyer. The downsides are mostly economical.

“The equipment is rather expensive and not easy to use. So the challenge for the field will be to develop this technology into an affordable ‘product’ that caretakers [sic], families or physicians can simply use without trained staff or extensive training,” he says. “In the interest of the patients and their families, we can hope that someone takes this challenge.”

https://singularityhub.com/2017/02/12/families-finally-hear-from-completely-paralyzed-patients-via-new-mind-reading-device/?utm_source=Singularity+Hub+Newsletter&utm_campaign=978304f198-Hub_Daily_Newsletter&utm_medium=email&utm_term=0_f0cf60cdae-978304f198-58158129

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By James Gallagher

An implant that beams instructions out of the brain has been used to restore movement in paralysed primates for the first time, say scientists.

Rhesus monkeys were paralysed in one leg due to a damaged spinal cord. The team at the Swiss Federal Institute of Technology bypassed the injury by sending the instructions straight from the brain to the nerves controlling leg movement. Experts said the technology could be ready for human trials within a decade.

Spinal-cord injuries block the flow of electrical signals from the brain to the rest of the body resulting in paralysis. It is a wound that rarely heals, but one potential solution is to use technology to bypass the injury.

In the study, a chip was implanted into the part of the monkeys’ brain that controls movement. Its job was to read the spikes of electrical activity that are the instructions for moving the legs and send them to a nearby computer. It deciphered the messages and sent instructions to an implant in the monkey’s spine to electrically stimulate the appropriate nerves. The process all takes place in real time. The results, published in the journal Nature, showed the monkeys regained some control of their paralysed leg within six days and could walk in a straight line on a treadmill.

Dr Gregoire Courtine, one of the researchers, said: “This is the first time that a neurotechnology has restored locomotion in primates.” He told the BBC News website: “The movement was close to normal for the basic walking pattern, but so far we have not been able to test the ability to steer.” The technology used to stimulate the spinal cord is the same as that used in deep brain stimulation to treat Parkinson’s disease, so it would not be a technological leap to doing the same tests in patients. “But the way we walk is different to primates, we are bipedal and this requires more sophisticated ways to stimulate the muscle,” said Dr Courtine.

Jocelyne Bloch, a neurosurgeon from the Lausanne University Hospital, said: “The link between decoding of the brain and the stimulation of the spinal cord is completely new. “For the first time, I can image a completely paralysed patient being able to move their legs through this brain-spine interface.”

Using technology to overcome paralysis is a rapidly developing field:
Brainwaves have been used to control a robotic arm
Electrical stimulation of the spinal cord has helped four paralysed people stand again
An implant has helped a paralysed man play a guitar-based computer game

Dr Mark Bacon, the director of research at the charity Spinal Research, said: “This is quite impressive work. Paralysed patients want to be able to regain real control, that is voluntary control of lost functions, like walking, and the use of implantable devices may be one way of achieving this. The current work is a clear demonstration that there is progress being made in the right direction.”

Dr Andrew Jackson, from the Institute of Neuroscience and Newcastle University, said: “It is not unreasonable to speculate that we could see the first clinical demonstrations of interfaces between the brain and spinal cord by the end of the decade.” However, he said, rhesus monkeys used all four limbs to move and only one leg had been paralysed, so it would be a greater challenge to restore the movement of both legs in people. “Useful locomotion also requires control of balance, steering and obstacle avoidance, which were not addressed,” he added.

The other approach to treating paralysis involves transplanting cells from the nasal cavity into the spinal cord to try to biologically repair the injury. Following this treatment, Darek Fidyka, who was paralysed from the chest down in a knife attack in 2010, can now walk using a frame.

Neither approach is ready for routine use.

http://www.bbc.com/news/health-37914543

Thanks to Kebmodee for bringing this to the It’s Interesting community.


Study paves way for personnel such as drone operators to have electrical pulses sent into their brains to improve effectiveness in high pressure situations.

US military scientists have used electrical brain stimulators to enhance mental skills of staff, in research that aims to boost the performance of air crews, drone operators and others in the armed forces’ most demanding roles.

The successful tests of the devices pave the way for servicemen and women to be wired up at critical times of duty, so that electrical pulses can be beamed into their brains to improve their effectiveness in high pressure situations.

The brain stimulation kits use five electrodes to send weak electric currents through the skull and into specific parts of the cortex. Previous studies have found evidence that by helping neurons to fire, these minor brain zaps can boost cognitive ability.

The technology is seen as a safer alternative to prescription drugs, such as modafinil and ritalin, both of which have been used off-label as performance enhancing drugs in the armed forces.

But while electrical brain stimulation appears to have no harmful side effects, some experts say its long-term safety is unknown, and raise concerns about staff being forced to use the equipment if it is approved for military operations.

Others are worried about the broader implications of the science on the general workforce because of the advance of an unregulated technology.

In a new report, scientists at Wright-Patterson Air Force Base in Ohio describe how the performance of military personnel can slump soon after they start work if the demands of the job become too intense.

“Within the air force, various operations such as remotely piloted and manned aircraft operations require a human operator to monitor and respond to multiple events simultaneously over a long period of time,” they write. “With the monotonous nature of these tasks, the operator’s performance may decline shortly after their work shift commences.”

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But in a series of experiments at the air force base, the researchers found that electrical brain stimulation can improve people’s multitasking skills and stave off the drop in performance that comes with information overload. Writing in the journal Frontiers in Human Neuroscience, they say that the technology, known as transcranial direct current stimulation (tDCS), has a “profound effect”.

For the study, the scientists had men and women at the base take a test developed by Nasa to assess multitasking skills. The test requires people to keep a crosshair inside a moving circle on a computer screen, while constantly monitoring and responding to three other tasks on the screen.

To investigate whether tDCS boosted people’s scores, half of the volunteers had a constant two milliamp current beamed into the brain for the 36-minute-long test. The other half formed a control group and had only 30 seconds of stimulation at the start of the test.

According to the report, the brain stimulation group started to perform better than the control group four minutes into the test. “The findings provide new evidence that tDCS has the ability to augment and enhance multitasking capability in a human operator,” the researchers write. Larger studies must now look at whether the improvement in performance is real and, if so, how long it lasts.

The tests are not the first to claim beneficial effects from electrical brain stimulation. Last year, researchers at the same US facility found that tDCS seemed to work better than caffeine at keeping military target analysts vigilant after long hours at the desk. Brain stimulation has also been tested for its potential to help soldiers spot snipers more quickly in VR training programmes.

Neil Levy, deputy director of the Oxford Centre for Neuroethics, said that compared with prescription drugs, electrical brain stimulation could actually be a safer way to boost the performance of those in the armed forces. “I have more serious worries about the extent to which participants can give informed consent, and whether they can opt out once it is approved for use,” he said. “Even for those jobs where attention is absolutely critical, you want to be very careful about making it compulsory, or there being a strong social pressure to use it, before we are really sure about its long-term safety.”

But while the devices may be safe in the hands of experts, the technology is freely available, because the sale of brain stimulation kits is unregulated. They can be bought on the internet or assembled from simple components, which raises a greater concern, according to Levy. Young people whose brains are still developing may be tempted to experiment with the devices, and try higher currents than those used in laboratories, he says. “If you use high currents you can damage the brain,” he says.

In 2014 another Oxford scientist, Roi Cohen Kadosh, warned that while brain stimulation could improve performance at some tasks, it made people worse at others. In light of the work, Kadosh urged people not to use brain stimulators at home.

If the technology is proved safe in the long run though, it could help those who need it most, said Levy. “It may have a levelling-up effect, because it is cheap and enhancers tend to benefit the people that perform less well,” he said.

https://www.theguardian.com/science/2016/nov/07/us-military-successfully-tests-electrical-brain-stimulation-to-enhance-staff-skills

Thanks to Kebmodee for bringing this to the It’s Interesting community.

Scientists have long been on a quest to find a way to implant electrodes that interface with neurons into the human brain. If successful, the idea could have huge implications for the treatment of Parkinson’s disease and other neurological disorders. Last month, a team of researchers from Italy and the UK made a huge step forward by showing that the world’s favorite wonder-material, graphene, can successfully interface with neurons.

Previous efforts by other groups using treated graphene had created an interface with a very low signal to noise ratio. But an interdisciplinary collaborative effort by the University of Trieste and the Cambridge Graphene Centre has developed a significantly improved electrode by working with untreated graphene.

“For the first time we interfaced graphene to neurons directly,” said Professor Laura Ballerini of the University of Trieste in Italy. “We then tested the ability of neurons to generate electrical signals known to represent brain activities, and found that the neurons retained their neuronal signaling properties unaltered. This is the first functional study of neuronal synaptic activity using uncoated graphene based materials.”

Prior to experimenting with graphene-based substrates (GBS), scientists implanted microelectrodes based on tungsten and silicon. Proof-of-concept experiments were successful, but these materials seem to suffer from the same fatal flaws. The body’s reaction to the insertion trauma is to form scarring tissue, inhibiting clear electrical signals. The structures were also prone to disconnecting, due to the stiffness of the materials, which were unsuitable for a semi-fluid organic environment.

Pure graphene is promising because it is flexible, non-toxic, and does not impair other cellular activity.

The team’s experiments on rat brain cell cultures showed that the untreated graphene electrodes interfaced well with neurons, transmitting electrical impulses normally with none of the adverse reactions seen previously.

The biocompatibility of graphene could allow it to be used to make graphene microelectrodes that could help measure, harness and control an impaired brain’s functions. It could be used to restore lost sensory functions to treat paralysis, control prosthetic devices such a robotic limbs for amputees and even control or diminish the impact of the out-of-control electrical impulses that cause motor disorders such as Parkinson’s and epilepsy.

“We are currently involved in frontline research in graphene technology towards biomedical applications,” said Professor Maurizio Prato from the University of Trieste. “In this scenario, the development and translation in neurology of graphene-based high-performance bio-devices requires the exploration of the interactions between graphene nano and micro-sheets with the sophisticated signaling machinery of nerve cells. Our work is only a first step in that direction.”

The results of this research were recently published in the journal ACS Nano. The research was funded by the Graphene Flagship, a European initiative that aims to connect theoretical and practical fields and reduce the time that graphene products spend in laboratories before being brought to market.

http://www.cam.ac.uk/research/news/graphene-shown-to-safely-interact-with-neurons-in-the-brain

Researchers at University of South Carolina (USC) and Wake Forest Baptist Medical Center have developed a brain prosthesis that is designed to help individuals suffering from memory loss.

The prosthesis, which includes a small array of electrodes implanted into the brain, has performed well in laboratory testing in animals and is currently being evaluated in human patients.

Designed originally at USC and tested at Wake Forest Baptist, the device builds on decades of research by Ted Berger and relies on a new algorithm created by Dong Song, both of the USC Viterbi School of Engineering. The development also builds on more than a decade of collaboration with Sam Deadwyler and Robert Hampson of the Department of Physiology & Pharmacology of Wake Forest Baptist who have collected the neural data used to construct the models and algorithms.

When your brain receives the sensory input, it creates a memory in the form of a complex electrical signal that travels through multiple regions of the hippocampus, the memory center of the brain. At each region, the signal is re-encoded until it reaches the final region as a wholly different signal that is sent off for long-term storage.

If there’s damage at any region that prevents this translation, then there is the possibility that long-term memory will not be formed. That’s why an individual with hippocampal damage (for example, due to Alzheimer’s disease) can recall events from a long time ago – things that were already translated into long-term memories before the brain damage occurred – but have difficulty forming new long-term memories.

Song and Berger found a way to accurately mimic how a memory is translated from short-term memory into long-term memory, using data obtained by Deadwyler and Hampson, first from animals, and then from humans. Their prosthesis is designed to bypass a damaged hippocampal section and provide the next region with the correctly translated memory.

That’s despite the fact that there is currently no way of “reading” a memory just by looking at its electrical signal.

“It’s like being able to translate from Spanish to French without being able to understand either language,” Berger said.

Their research was presented at the 37th Annual International Conference of the IEEE Engineering in Medicine and Biology Society in Milan on August 27, 2015.

The effectiveness of the model was tested by the USC and Wake Forest Baptist teams. With the permission of patients who had electrodes implanted in their hippocampi to treat chronic seizures, Hampson and Deadwyler read the electrical signals created during memory formation at two regions of the hippocampus, then sent that information to Song and Berger to construct the model. The team then fed those signals into the model and read how the signals generated from the first region of the hippocampus were translated into signals generated by the second region of the hippocampus.

In hundreds of trials conducted with nine patients, the algorithm accurately predicted how the signals would be translated with about 90 percent accuracy.

“Being able to predict neural signals with the USC model suggests that it can be used to design a device to support or replace the function of a damaged part of the brain,” Hampson said.
Next, the team will attempt to send the translated signal back into the brain of a patient with damage at one of the regions in order to try to bypass the damage and enable the formation of an accurate long-term memory.

http://medicalxpress.com/news/2015-09-scientists-bypass-brain-re-encoding-memories.html#nRlv


Paraplegic Adam Fritz works out with Kristen Johnson, a spinal cord injury recovery specialist, at the Project Walk facility in Claremont, California on September 24. A brain-to-computer technology that can translate thoughts into leg movements has enabled Fritz, paralyzed from the waist down by a spinal cord injury, to become the first such patient to walk without the use of robotics.

It’s a technology that sounds lifted from the latest Marvel movie—a brain-computer interface functional electrical stimulation (BCI-FES) system that enables paralyzed users to walk again. But thanks to neurologists, biomedical engineers and other scientists at the University of California, Irvine, it’s very much a reality, though admittedly with only one successful test subject so far.

The team, led by Zoran Nenadic and An H. Do, built a device that translates brain waves into electrical signals than can bypass the damaged region of a paraplegic’s spine and go directly to the muscles, stimulating them to move. To test it, they recruited 28-year-old Adam Fritz, who had lost the use of his legs five years earlier in a motorcycle accident.

Fritz first had to learn how exactly he’d been telling his legs to move for all those years before his accident. The research team fitted him with an electroencephalogram (EEG) cap that read his brain waves as he visualized moving an avatar in a virtual reality environment. After hours training on the video game, he eventually figured out how to signal “walk.”

The next step was to transfer that newfound skill to his legs. The scientists wired up the EEG device so that it would send electrical signals to the muscles in Fritz’s leg. And then, along with physical therapy to strengthen his legs, he would practice walking—his legs suspended a few inches off the ground—using only his brain (and, of course, the device). On his 20th visit, Fritz was finally able to walk using a harness that supported his body weight and prevented him from falling. After a little more practice, he walked using just the BCI-FES system. After 30 trials run over a period of 19 weeks, he could successfully walk through a 12-foot-long course.

As encouraging as the trial sounds, there are experts who suggest the design has limitations. “It appears that the brain EEG signal only contributed a walk or stop command,” says Dr. Chet Moritz, an associate professor of rehab medicine, physiology and biophysics at the University of Washington. “This binary signal could easily be provided by the user using a sip-puff straw, eye-blink device or many other more reliable means of communicating a simple ‘switch.’”

Moritz believes it’s unlikely that an EEG alone would be reliable enough to extract any more specific input from the brain while the test subject is walking. In other words, it might not be able to do much more beyond beginning and ending a simple motion like moving your legs forward—not so helpful in stepping over curbs or turning a corner in a hallway.

The UC Irvine team hopes to improve the capability of its technology. A simplified version of the system has the potential to work as a means of noninvasive rehabilitation for a wide range of paralytic conditions, from less severe spinal cord injuries to stroke and multiple sclerosis.

“Once we’ve confirmed the usability of this noninvasive system, we can look into invasive means, such as brain implants,” said Nenadic in a statement announcing the project’s success. “We hope that an implant could achieve an even greater level of prosthesis control because brain waves are recorded with higher quality. In addition, such an implant could deliver sensation back to the brain, enabling the user to feel their legs.

http://www.newsweek.com/paralyzed-man-walks-again-using-only-his-mind-379531

There have been tentative steps into thought-controlled drones in the past, but Tekever and a team of European researchers just kicked things up a notch. They’ve successfully tested Brainflight, a project that uses your mental activity (detected through a cap) to pilot an unmanned aircraft. You have to learn how to fly on your own, but it doesn’t take long before you’re merely thinking about where you want to go. And don’t worry about crashing because of distractions or mental trauma, like seizures — there are “algorithms” to prevent the worst from happening.

You probably won’t be using Brainflight to fly anything larger than a small drone, at least not in the near future. There’s no regulatory framework that would cover mind-controlled aircraft, after all. Tekever is hopeful that its technology will change how we approach transportation, though. It sees brain power reducing complex activities like flying or driving to something you can do instinctively, like walking — you’d have freedom to focus on higher-level tasks like navigation. The underlying technology would also let people with injuries and physical handicaps steer vehicles and their own prosthetic limbs. Don’t be surprised if you eventually need little more than some headgear to take to the skies.

http://www.engadget.com/2015/02/25/tekever-mind-controlled-drone/?ncid=rss_truncated