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PINning down future problems

Study finds hackers could use brainwaves to steal passwords

Researchers at the University of Alabama at Birmingham suggest that brainwave-sensing headsets, also known as EEG or electroencephalograph headsets, need better security after a study reveals hackers could guess a user’s passwords by monitoring their brainwaves.

EEG headsets are advertised as allowing users to use only their brains to control robotic toys and video games specifically developed to be played with an EEG headset. There are only a handful on the market, and they range in price from $150 to $800.

Nitesh Saxena, Ph.D., associate professor in the UAB College of Arts and Sciences Department of Computer and Information Sciences, and Ph.D. student Ajaya Neupane and former master’s student Md Lutfor Rahman, found that a person who paused a video game and logged into a bank account while wearing an EEG headset was at risk for having their passwords or other sensitive data stolen by a malicious software program.

“These emerging devices open immense opportunities for everyday users,” Saxena said. “However, they could also raise significant security and privacy threats as companies work to develop even more advanced brain-computer interface technology.”

Saxena and his team used one EEG headset currently available to consumers online and one clinical-grade headset used for scientific research to demonstrate how easily a malicious software program could passively eavesdrop on a user’s brainwaves. While typing, a user’s inputs correspond with their visual processing, as well as hand, eye and head muscle movements. All these movements are captured by EEG headsets. The team asked 12 people to type a series of randomly generated PINs and passwords into a text box as if they were logging into an online account while wearing an EEG headset, in order for the software to train itself on the user’s typing and the corresponding brainwave.

“In a real-world attack, a hacker could facilitate the training step required for the malicious program to be most accurate, by requesting that the user enter a predefined set of numbers in order to restart the game after pausing it to take a break, similar to the way CAPTCHA is used to verify users when logging onto websites,” Saxena said.

The team found that, after a user entered 200 characters, algorithms within the malicious software program could make educated guesses about new characters the user entered by monitoring the EEG data recorded. The algorithm was able to shorten the odds of a hacker’s guessing a four-digit numerical PIN from one in 10,000 to one in 20 and increased the chance of guessing a six-letter password from about 500,000 to roughly one in 500.

EEG has been used in the medical field for more than half a century as a noninvasive method for recording electrical activity in the brain. Electrodes are placed on the surface of the scalp to detect brain waves. An EEG machine then amplifies the signals and records them in a wave pattern on graph paper or a computer. EEG can be combined with a brain-computer interface to allow a person to control external devices. This technology was once highly expensive and used mostly for scientific research, like the production of neuroprosthetic applications to help disabled patients control prosthetic limbs by thinking about the movements. However, it is now being marketed to consumers in the form of a wireless headset and is becoming popular in the gaming and entertainment industries.

“Given the growing popularity of EEG headsets and the variety of ways in which they could be used, it is inevitable that they will become part of our daily lives, including while using other devices,” Saxena said. “It is important to analyze the potential security and privacy risks associated with this emerging technology to raise users’ awareness of the risks and develop viable solutions to malicious attacks.”

One potential solution proposed by Saxena and his team is the insertion of noise anytime a user types a password or PIN while wearing an EEG headset.

Man with quadriplegia employs injury bridging technologies to move again—just by thinking

First recipient of implanted brain-recording and muscle-stimulating systems reanimates limb that had been stilled for eight years

Bill Kochevar grabbed a mug of water, drew it to his lips and drank through the straw.

His motions were slow and deliberate, but then Kochevar hadn’t moved his right arm or hand for eight years.

And it took some practice to reach and grasp just by thinking about it.

Kochevar, who was paralyzed below his shoulders in a bicycling accident, is believed to be the first person with quadriplegia in the world to have arm and hand movements restored with the help of two temporarily implanted technologies.

A brain-computer interface with recording electrodes under his skull, and a functional electrical stimulation (FES) system* activating his arm and hand, reconnect his brain to paralyzed muscles.

Holding a makeshift handle pierced through a dry sponge, Kochevar scratched the side of his nose with the sponge. He scooped forkfuls of mashed potatoes from a bowl—perhaps his top goal—and savored each mouthful.

“For somebody who’s been injured eight years and couldn’t move, being able to move just that little bit is awesome to me,” said Kochevar, 56, of Cleveland. “It’s better than I thought it would be.”

Kochevar is the focal point of research led by Case Western Reserve University, the Cleveland Functional Electrical Stimulation (FES) Center at the Louis Stokes Cleveland VA Medical Center and University Hospitals Cleveland Medical Center (UH). A study of the work was published in the The Lancet March 28 at 6:30 p.m. U.S. Eastern time.

“He’s really breaking ground for the spinal cord injury community,” said Bob Kirsch, chair of Case Western Reserve’s Department of Biomedical Engineering, executive director of the FES Center and principal investigator (PI) and senior author of the research. “This is a major step toward restoring some independence.”

When asked, people with quadriplegia say their first priority is to scratch an itch, feed themselves or perform other simple functions with their arm and hand, instead of relying on caregivers.

“By taking the brain signals generated when Bill attempts to move, and using them to control the stimulation of his arm and hand, he was able to perform personal functions that were important to him,” said Bolu Ajiboye, assistant professor of biomedical engineering and lead study author.

Technology and training

The research with Kochevar is part of the ongoing BrainGate2* pilot clinical trial being conducted by a consortium of academic and VA institutions assessing the safety and feasibility of the implanted brain-computer interface (BCI) system in people with paralysis. Other investigational BrainGate research has shown that people with paralysis can control a cursor on a computer screen or a robotic arm (braingate.org).

“Every day, most of us take for granted that when we will to move, we can move any part of our body with precision and control in multiple directions and those with traumatic spinal cord injury or any other form of paralysis cannot,” said Benjamin Walter, associate professor of neurology at Case Western Reserve School of Medicine, clinical PI of the Cleveland BrainGate2 trial and medical director of the Deep Brain Stimulation Program at UH Cleveland Medical Center.

“The ultimate hope of any of these individuals is to restore this function,” Walter said. “By restoring the communication of the will to move from the brain directly to the body this work will hopefully begin to restore the hope of millions of paralyzed individuals that someday they will be able to move freely again.”

Jonathan Miller, assistant professor of neurosurgery at Case Western Reserve School of Medicine and director of the Functional and Restorative Neurosurgery Center at UH, led a team of surgeons who implanted two 96-channel electrode arrays—each about the size of a baby aspirin—in Kochevar’s motor cortex, on the surface of the brain.

The arrays record brain signals created when Kochevar imagines movement of his own arm and hand. The brain-computer interface extracts information from the brain signals about what movements he intends to make, then passes the information to command the electrical stimulation system.

To prepare him to use his arm again, Kochevar first learned how to use his brain signals to move a virtual-reality arm on a computer screen.

“He was able to do it within a few minutes,” Kirsch said. “The code was still in his brain.”

As Kochevar’s ability to move the virtual arm improved through four months of training, the researchers believed he would be capable of controlling his own arm and hand.

Miller then led a team that implanted the FES systems’ 36 electrodes that animate muscles in the upper and lower arm.

The BCI decodes the recorded brain signals into the intended movement command, which is then converted by the FES system into patterns of electrical pulses.

The pulses sent through the FES electrodes trigger the muscles controlling Kochevar’s hand, wrist, arm, elbow and shoulder. To overcome gravity that would otherwise prevent him from raising his arm and reaching, Kochevar uses a mobile arm support, which is also under his brain’s control.

New Capabilities

Eight years of muscle atrophy required rehabilitation. The researchers exercised Kochevar’s arm and hand with cyclical electrical stimulation patterns. Over 45 weeks, his strength, range of motion and endurance improved. As he practiced movements, the researchers adjusted stimulation patterns to further his abilities.

Kochevar can make each joint in his right arm move individually. Or, just by thinking about a task such as feeding himself or getting a drink, the muscles are activated in a coordinated fashion.

When asked to describe how he commanded the arm movements, Kochevar told investigators, “I’m making it move without having to really concentrate hard at it…I just think ‘out’…and it goes.”

Kocehvar is fitted with temporarily implanted FES technology that has a track record of reliable use in people. The BCI and FES system together represent early feasibility that gives the research team insights into the potential future benefit of the combined system.

Advances needed to make the combined technology usable outside of a lab are not far from reality, the researchers say. Work is underway to make the brain implant wireless, and the investigators are improving decoding and stimulation patterns needed to make movements more precise. Fully implantable FES systems have already been developed and are also being tested in separate clinical research.

Kochevar welcomes new technology—even if it requires more surgery—that will enable him to move better. “This won’t replace caregivers,” he said. “But, in the long term, people will be able, in a limited way, to do more for themselves.”

The investigational BrainGate technology was initially developed in the Brown University laboratory of John Donoghue, now the founding director of the Wyss Center for Bio and Neuroengineering in Geneva, Switzerland. The implanted recording electrodes are known as the Utah array, originally designed by Richard Normann, Emeritus Distinguished Professor of Bioengineering at the University of Utah.

The report in Lancet is the result of a long-running collaboration between Kirsch, Ajiboye and the multi-institutional BrainGate consortium. Leigh Hochberg, a neurologist and neuroengineer at Massachusetts General Hospital, Brown University and the VA RR&D Center for Neurorestoration and Neurotechnology in Providence, Rhode Island, directs the pilot clinical trial of the BrainGate system and is a study co-author.

“It’s been so inspiring to watch Mr. Kochevar move his own arm and hand just by thinking about it,” Hochberg said. “As an extraordinary participant in this research, he’s teaching us how to design a new generation of neurotechnologies that we all hope will one day restore mobility and independence for people with paralysis.”

Paralyzed ALS patient operates speech computer with her mind

In the UMC Utrecht a brain implant has been placed in a patient enabling her to operate a speech computer with her mind. The researchers and the patient worked intensively to get the settings right. She can now communicate at home with her family and caregivers via the implant. That a patient can use this technique at home is unique in the world. This research was published in the New England Journal of Medicine.

Because she suffers from ALS disease, the patient is no longer able to move and speak. Doctors placed electrodes in her brain, and the electrodes pick up brain activity. This enables her to wirelessly control a speech computer that she now uses at home.

Mouse click

The patient operates the speech computer by moving her fingers in her mind. This changes the brain signal under the electrodes. That change is converted into a mouse click. On a screen in front of her she can see the alphabet, plus some additional functions such as deleting a letter or word and selecting words based on the letters she has already spelled. The letters on the screen light up one by one. She selects a letter by influencing the mouse click at the right moment with her brain. That way she can compose words, letter by letter, which are then spoken by the speech computer. This technique is comparable to actuating a speech computer via a push-button (with a muscle that can still function, for example, in the neck or hand). So now, if a patient lacks muscle activity, a brain signal can be used instead.

Wireless

The patient underwent surgery during which electrodes were placed on her brain through tiny holes in her skull. A small transmitter was then placed in her body below her collarbone. This transmitter receives the signals from the electrodes via subcutaneous wires, amplifies them and transmits them wirelessly. The mouse click is calculated from these signals, actuating the speech computer. The patient is closely supervised. Shortly after the operation, she started on a journey of discovery together with the researchers to find the right settings for the device and the perfect way to get her brain activity under control. It started with a “simple” game to practice the art of clicking. Once she mastered clicking, she focused on the speech computer. She can now use the speech computer without the help of the research team.

The UMC Utrecht Brain Center has spent many years researching the possibility of controlling a computer by means of electrodes that capture brain activity. Working with a speech computer driven by brain signals measured with a bathing cap with electrodes has long been tested in various research laboratories. That a patient can use the technique at home, through invisible, implanted electrodes, is unique in the world.

If the implant proves to work well in three people, the researchers hope to launch a larger, international trial. Ramsey: “We hope that these results will stimulate research into more advanced implants, so that some day not only people with communication problems, but also people with paraplegia, for example, can be helped.”

(Image caption: This type of electrocorticography (ECoG) grid, which is implanted in patients about to undergo epilepsy surgery, enables researchers to record and transmit electrical signals to and from the surface of the brain. Credit: Mark Stone/University of Washington)

For the first time in humans, researchers use brain surface stimulation to provide ‘touch’ feedback to direct movement

In the quest to restore movement to people with spinal cord injuries, researchers have focused on getting brain signals to disconnected nerves and muscles that no longer receive messages that would spur them to move.

But grasping a cup or brushing hair or cooking a meal requires other feedback that has been lost in amputees and individuals with paralysis — a sense of touch. The brain needs information from a fingertip or limb or external device to understand how firmly a person is gripping or how much pressure is needed to perform everyday tasks.

Now, University of Washington researchers at the National Science Foundation Center for Sensorimotor Neural Engineering (CSNE) have used direct stimulation of the human brain surface to provide basic sensory feedback through artificial electrical signals, enabling a patient to control movement while performing a simple task: opening and closing his hand.

It’s a first step towards developing “closed loop,” bi-directional brain-computer interfaces (BBCIs) that enable two-way communication between parts of the nervous system. They would also allow the brain to directly control external prosthetics or other devices that can enhance movement — or even reanimate a paralyzed limb — while getting sensory feedback.

The results of this research will be published in the Oct.-Dec. 2016 issue of IEEE Transactions on Haptics. An early-access version of the paper is available online.

“We were able to provide a baseline degree of sensory feedback by direct cortical stimulation of the brain,” said lead author and UW bioengineering doctoral student Jeneva Cronin. “To our knowledge this is the first time it’s been done in a human patient who was awake and performing a motor task that depended on that feedback.”

The team of bioengineers, computer scientists and medical researchers from the CSNE and UW’s GRIDLab used electrical signals of different current intensities, dictated by the position of the patient’s hand measured by a glove he wore, to stimulate the patient’s brain that had been implanted with electrocorticographic (ECoG) electrodes. The patient then used those artificial signals delivered to the brain to “sense” how the researchers wanted him to move his hand.

“The question is: Can humans use novel electrical sensations that they’ve never felt before, perceive them at different levels and use this to do a task? And the answer seems to be yes,” said co-author and UW bioengineering doctoral student James Wu. “Whether this type of sensation can be as diverse as the textures and feelings that we can sense tactilely is an open question.”

They would also allow the brain to directly control external prosthetics or other devices that can enhance movement — or even reanimate a paralyzed limb — while getting sensory feedback.

It’s difficult for a person to mimic natural movements — whether using a prosthetic device or a limb that has become disconnected from the brain by neurological injury — without sensation. Though there are devices to assist patients with paralysis or who have undergone amputations with basic function, being able to feel again ranks highly on their priorities, researchers said.

Restoring this sensory feedback requires developing an “artificial” language of electrical signals that the brain can interpret as sensation and incorporate as useful feedback when performing a task.

The UW CSNE team frequently works with patients about to undergo epilepsy surgery who have recently had an ECoG electrode grid implanted on the surface of their brain. For several days or weeks, doctors constantly monitor their brain activity to pinpoint the origin of their seizures before operating.

By consenting to participate in research studies during this period when their brain is “wired,” these patients enable researchers to answer basic neurological questions. They can test which parts of the brain are activated during different behaviors, what happens when a certain region of the brain’s cortex is stimulated and even how to induce brain plasticity to promote rehabilitation and healing across damaged areas.

The potential to use ECoG electrodes implanted on the surface of the brain in future prosthetic or rehabilitative applications offers several advantages — the signals are stronger and more accurate than sensors placed on the scalp, but less invasive than ones that penetrate the brain, as in a recent study by University of Pittsburgh researchers.

In the UW study, three patients wore a glove embedded with sensors that provided data about where their fingers and joints were positioned. They were asked to stay within a target position somewhere between having their hands open and closed without being able to see what that target position was. The only feedback they received about the target hand position was artificial electrical data delivered by the research team.

When their hands opened too far, they received no electrical stimulus to the brain. When their hand was too closed – similar to squeezing something too hard – the electrical stimuli was provided at a higher intensity.

One patient was able to achieve accuracies in reaching the target position well above chance when receiving the electrical feedback. Performance dropped when the patient received random signals regardless of hand position, suggesting that the subject had been using the artificial sensory feedback to control hand movement.

Providing that artificial sensory feedback in a way that the brain can understand is key to developing prosthetics, implants or other neural devices that could restore a sense of position, touch or feeling in patients where that connection has been severed.

“Right now we’re using very primitive kinds of codes where we’re changing only frequency or intensity of the stimulation, but eventually it might be more like a symphony,” said co-author Rajesh Rao, CSNE director and UW professor of computer science & engineering.

“That’s what you’d need to do to have a very natural grip for tasks such as preparing a dish in the kitchen. When you want to pick up the salt shaker and all your ingredients, you need to exert just the right amount of pressure. Any day-to-day task like opening a cupboard or lifting a plate or breaking an egg requires this complex sensory feedback.”

(Image caption: Measurement of brain activity in a patient with phantom limb pain. Credit: Osaka University)

Cause of phantom limb pain in amputees, and potential treatment, identified

Researchers have discovered that a ‘reorganisation’ of the wiring of the brain is the underlying cause of phantom limb pain, which occurs in the vast majority of individuals who have had limbs amputated, and a potential method of treating it which uses artificial intelligence techniques.

The researchers, led by a group from Osaka University in Japan in collaboration with the University of Cambridge, used a brain-machine interface to train a group of ten individuals to control a robotic arm with their brains. They found that if a patient tried to control the prosthetic by associating the movement with their missing arm, it increased their pain, but training them to associate the movement of the prosthetic with the unaffected hand decreased their pain.

Their results, reported in the journal Nature Communications, demonstrate that in patients with chronic pain associated with amputation or nerve injury, there are ‘crossed wires’ in the part of the brain associated with sensation and movement, and that by mending that disruption, the pain can be treated. The findings could also be applied to those with other forms of chronic pain, including pain due to arthritis.

Approximately 5,000 amputations are carried out in the UK every year, and those with type 1 or type 2 diabetes are at particular risk of needing an amputation. In most cases, individuals who have had a hand or arm amputated, or who have had severe nerve injuries which result in a loss of sensation in their hand, continue to feel the existence of the affected hand as if it were still there. Between 50 and 80 percent of these patients suffer with chronic pain in the ‘phantom’ hand, known as phantom limb pain.

“Even though the hand is gone, people with phantom limb pain still feel like there’s a hand there – it basically feels painful, like a burning or hypersensitive type of pain, and conventional painkillers are ineffective in treating it,” said study co-author Dr Ben Seymour, a neuroscientist based in Cambridge’s Department of Engineering. “We wanted to see if we could come up with an engineering-based treatment as opposed to a drug-based treatment.”

A popular theory of the cause of phantom limb pain is faulty ‘wiring’ of the sensorimotor cortex, the part of the brain that is responsible for processing sensory inputs and executing movements. In other words, there is a mismatch between a movement and the perception of that movement.

In the study, Seymour and his colleagues, led by Takufumi Yanagisawa from Osaka University, used a brain-machine interface to decode the neural activity of the mental action needed for a patient to move their ‘phantom’ hand, and then converted the decoded phantom hand movement into that of a robotic neuroprosthetic using artificial intelligence techniques.

“We found that the better their affected side of the brain got at using the robotic arm, the worse their pain got,” said Yanagisawa. “The movement part of the brain is working fine, but they are not getting sensory feedback – there’s a discrepancy there.”

The researchers then altered their technique to train the ‘wrong’ side of the brain: for example, a patient who was missing their left arm was trained to move the prosthetic arm by decoding movements associated with their right arm, or vice versa. When they were trained in this counter-intuitive technique, the patients found that their pain significantly decreased. As they learned to control the arm in this way, it takes advantage of the plasticity – the ability of the brain to restructure and learn new things – of the sensorimotor cortex, showing a clear link between plasticity and pain.

Although the results are promising, Seymour warns that the effects are temporary, and require a large, expensive piece of medical equipment to be effective. However, he believes that a treatment based on their technique could be available within five to ten years. “Ideally, we’d like to see something that people could have at home, or that they could incorporate with physio treatments,” he said. “But the results demonstrate that combining AI techniques with new technologies is a promising avenue for treating pain, and an important area for future UK-Japan research collaboration.”

Can the brain feel it? The world’s smallest extracellular needle-electrodes

A research team in the Department of Electrical and Electronic Information Engineering and the Electronics-Inspired Interdisciplinary Research Institute (EIIRIS) at Toyohashi University of Technology developed 5-μm-diameter needle-electrodes on 1 mm × 1 mm block modules. This tiny needle may help solve the mysteries of the brain and facilitate the development of a brain-machine interface. The research results were reported in Scientific Reports on Oct 25, 2016.

(Image caption: Extracellular needle-electrode with a diameter of 5 μm mounted on a connector)

The neuron networks in the human brain are extremely complex. Microfabricated silicon needle-electrode devices were expected to be an innovation that would be able to record and analyze the electrical activities of the microscale neuronal circuits in the brain.

However, smaller needle technologies (e.g., needle diameter < 10 μm) are necessary to reduce damage to brain tissue. In addition to the needle geometry, the device substrate should be minimized not only to reduce the total amount of damage to tissue but also to enhance the accessibility of the electrode in the brain. Thus, these electrode technologies will realize new experimental neurophysiological concepts.

A research team in the Department of Electrical and Electronic Information Engineering and the EIIRIS at Toyohashi University of Technology developed 5- μm-diameter needle-electrodes on 1 mm × 1 mm block modules.

The individual microneedles are fabricated on the block modules, which are small enough to use in the narrow spaces present in brain tissue; as demonstrated in the recording using mouse cerebrum cortices. In addition, the block module remarkably improves the design variability in the packaging, offering numerous in vivo recording applications.

“We demonstrated the high design variability in the packaging of our electrode device, and in vivo neuronal recordings were performed by simply placing the device on a mouse’s brain. We were very surprised that high quality signals of a single unit were stably recorded over a long period using the 5-μm-diameter needle,” explained the first author, Assistant Professor Hirohito Sawahata, and co-author, researcher Shota Yamagiwa.

The leader of the research team, Associate Professor Takeshi Kawano said: “Our silicon needle technology offers low invasive neuronal recordings and provides novel methodologies for electrophysiology; therefore, it has the potential to enhance experimental neuroscience.” He added, “We expect the development of applications to solve the mysteries of the brain and the development of brain–machine interfaces.”