Move Over, Iron Man. A Real-Life Power Suit Helped This Paralyzed Grandmother Learn to Run.
Puschel Sorensen first noticed something was wrong when her fingertips began to tingle. Later that day, she grew weak and fell.
It picked up small electrical impulses on her skin's surface and turned them into full movement in her legs.
Her family rushed her to the doctor, where she received the devastating diagnosis of Guillain-Barré Syndrome -- a rare and rapidly progressing autoimmune disorder that attacks the myelin sheath covering nerves.
Sorensen, a once-spry grandmother in her late fifties, spent 54 days in intensive care in 2018. When she was finally transferred to a rehab facility near her home in Florida, she was still on a feeding tube and ventilator, and was paralyzed from the neck down. Progress with traditional physical therapy was slow.
Sorensen in the hospital after her diagnosis of Guillain-Barré syndrome.
And then everything changed. Sorensen began using a cutting-edge technology called an exoskeleton to relearn how to walk. In the vein of Iron Man's fictional power suit, it confers strength and mobility to the wearer that isn't possible otherwise. In Sorensen's case, her device, called HAL – for hybrid assistive limb -- picked up small electrical impulses on her skin's surface and turned them into full movement in her legs while she attempted to walk on a treadmill.
"It was very difficult, but super awesome," recalls Sorensen, of first using the device. "The robot was having to do all the work for me."
Amazingly, within a year, she was running. She's one of 38 patients who have used HAL to recover from accidents or medical catastrophes.
Cyberdyne's hybrid assistive limb technology.
"How do you thank someone for giving them back the ability to walk, the ability to live your life again?" Sorensen asks effusively.
It's still early days for such exoskeleton devices, which number perhaps a few thousand worldwide, according to data from the handful of manufacturers who create them with any scale. But the devices' ability to dramatically rehabilitate patients like Sorensen highlights their potential to extract untold numbers of people from wheelchairs, and even to usher in a new paradigm for caregiving – one of the fastest growing segments of the U.S. economy.
"I've been a physical therapist for 16 years, and (these devices) help teach patients the right way to move in rehabilitation," says Robert McIver, director of clinical technology at the Brooks Cybernic Treatment Center, part of the Brooks Rehabilitation Hospital in Jacksonville, Fla, where Sorensen recovered.
Another patient there, a 17-year-old named George with a snowboarding injury that paralyzed his legs, was getting around with a walker within 20 sessions.
As patients progress in their recoveries, so does exoskeleton technology. Jack Peurach, CEO of Ekso, one of the leaders in the space, believes within a decade they could resemble an article of clothing (a "magic pair of pants" is his phrase). They also may become inexpensive and reliable enough to transition from a medical to a consumer device. McIver sees them eventually being used in the home on an ongoing basis as a personal assistive device, much like a walker or cane, to prevent falls in elderly people.
Such a transition "certainly could eventually lessen the need for caregivers," says Sharona Hoffman, a professor of law at Case Western University in Cleveland who has written extensively on aging and bioethics. "We have a real shortage of caregivers, so that would be a good thing."
Of course, having an aging and disabled population using exoskeletons in much the same way as an Apple Watch raises issues of its own.
Dr. Elizabeth Landsverk, a California-based geriatrician and founder of a company that performs house calls for elderly patients, believes the tech holds some promise in easing the burden on caregivers, who sometimes have to lift or move patients without assistance. But she also believes exoskeletons could become overhyped.
"I don't see robotics as completely replacing the caregiver," she says. And even if exoskeletons became akin to articles of clothing, she is skeptical of how convenient they could become.
"It's hard enough to get into support hose. Would an older person be able to get in and out of it on their own?" she asks, noting that a patient's cognitive levels could pose a huge barrier to donning such a device without assistance.
If personal exoskeletons did wildly succeed, Hoffman wonders whether they would leave the elderly more physically mobile yet also more socially isolated, since caregivers or even residing in an assisted living facility may no longer be required. Or, if they were priced in the hundreds or thousands of dollars, he worries that the cost would exacerbate social inequalities among the elderly and disabled.
"It's almost like a bad dream that [my illness] happened."
With any technology that confers superhuman ability, there's also the question of appropriate usage. Even the fictional Power Loader in the movie Alien required an operator's license. In the real world, such an approach would likely pay dividends.
"We would have to make sure physicians are well-trained in these devices, and patients have a way of getting training to operate them that is thorough and responsible," Hoffman says.
But despite some unresolved questions, it is a remarkable achievement to be able to give people back their lives thanks to new technology.
"It's almost like a bad dream that [my illness] happened," says Sorensen, who managed to walk in her daughter's wedding after her recovery. "Because now everything is pretty much back to normal and it's awesome."
Inside the Atlantis Space Shuttle, astronauts waited for liftoff. At T-minus six seconds, the main engines ignited, rattling the capsule “like a skyscraper in an earthquake,” according to astronaut Tom Jones, describing the 1988 launch in Air & Space Magazine. Liftoff came with what felt like “a massive kick in the back,” he recalled, along with more shaking. As the rocket accelerated to three times the force of gravity on Earth, “It felt as if two of my friends were standing on my chest and wouldn’t get off!” Finally, at 25 times the speed of sound, Atlantis reached orbit. The main engines cut off, and the astronauts were weightless.
Since 1961, NASA has sent hundreds of astronauts into space while working to making their voyages safer and smoother. Yet, challenges remain. Weightlessness may look amusing when watched from Earth, but it has myriad effects on cognition, movement and other functions. When missions to space stretch to six months or longer, microgravity can harm astronauts’ health and performance, making it more difficult to operate their spacecraft.
Yesterday, NASA astronaut Frank Rubio returned to Earth after over one year, the longest single spaceflight for a U.S. astronaut. But this is just the start; longer and more complex missions into deep space loom ahead, from returning to the moon in 2025 to eventually sending humans to Mars. Understanding how spaceflight affects the body is vital to success. By studying these impacts, NASA aims to help astronauts perform in space as well as they do on Earth.
The dangers of microgravity are real
A NASA report published in 2016 details a long list of incidents and near-misses caused – at least partly – by space-induced changes in astronauts’ vision and coordination. These issues make it harder to move with precision and to judge distance and velocity.
According to the report, in 1997, a resupply ship collided with the Mir space station, possibly because a crew member bumped into the commander during the final docking maneuver. This mishap caused significant damage to the space station.
Returns to Earth suffered from problems, too. The same report notes that touchdown speeds during the first 100 space shuttle landings were “outside acceptable limits. The fastest landing on record – 224 knots (258 miles) per hour – was linked to the commander’s momentary spatial disorientation.” Earlier, each of the six Apollo crews that landed on the moon had difficulty recognizing moon landmarks and estimating distances. For example, Apollo 15 landed in an unplanned area, ultimately straddling the rim of a five-foot deep crater on the moon, harming one of its engines.
Spaceflight causes unique stresses on astronauts’ brains and central nervous systems. NASA is working to reduce these harmful effects.
Space messes up your brain
In space, astronauts face the challenges of microgravity, ionizing radiation, social isolation, high workloads, altered circadian rhythms, monotony, confined living quarters and a high-risk environment. Among these issues, microgravity is one of the most consequential in terms of physiological changes. It changes the brain’s structure and its functioning, which can hurt astronauts’ performance.
The brain shifts upwards within the skull, displacing the cerebrospinal fluid, which reduces the brain’s cushioning. Essentially, the brain becomes crowded inside the skull like a pair of too-tight shoes.
That’s partly because of how being in space alters blood flow. On Earth, gravity pulls our blood and other internal fluids toward our feet, but our circulatory valves ensure that the fluids are evenly distributed throughout the body. In space, there’s not enough gravity to pull the fluids down, and they shift up, says Rachael D. Seidler, a physiologist specializing in spaceflight at the University of Florida and principal investigator on many space-related studies. The head swells and legs appear thinner, causing what astronauts call “puffy face chicken legs.”
“The brain changes at the structural and functional level,” says Steven Jillings, equilibrium and aerospace researcher at the University of Antwerp in Belgium. “The brain shifts upwards within the skull,” displacing the cerebrospinal fluid, which reduces the brain’s cushioning. Essentially, the brain becomes crowded inside the skull like a pair of too-tight shoes. Some of the displaced cerebrospinal fluid goes into cavities within the brain, called ventricles, enlarging them. “The remaining fluids pool near the chest and heart,” explains Jillings. After 12 consecutive months in space, one astronaut had a ventricle that was 25 percent larger than before the mission.
Some changes reverse themselves while others persist for a while. An example of a longer-lasting problem is spaceflight-induced neuro-ocular syndrome, which results in near-sightedness and pressure inside the skull. A study of approximately 300 astronauts shows near-sightedness affects about 60 percent of astronauts after long missions on the International Space Station (ISS) and more than 25 percent after spaceflights of only a few weeks.
Another long-term change could be the decreased ability of cerebrospinal fluid to clear waste products from the brain, Seidler says. That’s because compressing the brain also compresses its waste-removing glymphatic pathways, resulting in inflammation, vulnerability to injuries and worsening its overall health.
The effects of long space missions were best demonstrated on astronaut twins Scott and Mark Kelly. This NASA Twins Study showed multiple, perhaps permanent, changes in Scott after his 340-day mission aboard the ISS, compared to Mark, who remained on Earth. The differences included declines in Scott’s speed, accuracy and cognitive abilities that persisted longer than six months after returning to Earth in March 2016.
By the end of 2020, Scott’s cognitive abilities improved, but structural and physiological changes to his eyes still remained, he said in a BBC interview.
“It seems clear that the upward shift of the brain and compression of the surrounding tissues with ventricular expansion might not be a good thing,” Seidler says. “But, at this point, the long-term consequences to brain health and human performance are not really known.”
NASA astronaut Kate Rubins conducts a session for the Neuromapping investigation.
Staying sharp in space
To investigate how prolonged space travel affects the brain, NASA launched a new initiative called the Complement of Integrated Protocols for Human Exploration Research (CIPHER). “CIPHER investigates how long-duration spaceflight affects both brain structure and function,” says neurobehavioral scientist Mathias Basner at the University of Pennsylvania, a principal investigator for several NASA studies. “Through it, we can find out how the brain adapts to the spaceflight environment and how certain brain regions (behave) differently after – relative to before – the mission.”
To do this, he says, “Astronauts will perform NASA’s cognition test battery before, during and after six- to 12-month missions, and will also perform the same test battery in an MRI scanner before and after the mission. We have to make sure we better understand the functional consequences of spaceflight on the human brain before we can send humans safely to the moon and, especially, to Mars.”
As we go deeper into space, astronauts cognitive and physical functions will be even more important. “A trip to Mars will take about one year…and will introduce long communication delays,” Seidler says. “If you are on that mission and have a problem, it may take eight to 10 minutes for your message to reach mission control, and another eight to 10 minutes for the response to get back to you.” In an emergency situation, that may be too late for the response to matter.
“On a mission to Mars, astronauts will be exposed to stressors for unprecedented amounts of time,” Basner says. To counter them, NASA is considering the continuous use of artificial gravity during the journey, and Seidler is studying whether artificial gravity can reduce the harmful effects of microgravity. Some scientists are looking at precision brain stimulation as a way to improve memory and reduce anxiety due to prolonged exposure to radiation in space.
To boldly go where no astronauts have gone before, they must have optimal reflexes, vision and decision-making. In the era of deep space exploration, the brain—without a doubt—is the final frontier.
Additionally, NASA is scrutinizing each aspect of the mission, including astronaut exercise, nutrition and intellectual engagement. “We need to give astronauts meaningful work. We need to stimulate their sensory, cognitive and other systems appropriately,” Basner says, especially given their extreme confinement and isolation. The scientific experiments performed on the ISS – like studying how microgravity affects the ability of tissue to regenerate is a good example.
“We need to keep them engaged socially, too,” he continues. The ISS crew, for example, regularly broadcasts from space and answers prerecorded questions from students on Earth, and can engage with social media in real time. And, despite tight quarters, NASA is ensuring the crew capsule and living quarters on the moon or Mars include private space, which is critical for good mental health.
Exploring deep space builds on a foundation that began when astronauts first left the planet. With each mission, scientists learn more about spaceflight effects on astronauts’ bodies. NASA will be using these lessons to succeed with its plans to build science stations on the moon and, eventually, Mars.
“Through internally and externally led research, investigations implemented in space and in spaceflight simulations on Earth, we are striving to reduce the likelihood and potential impacts of neurostructural changes in future, extended spaceflight,” summarizes NASA scientist Alexandra Whitmire. To boldly go where no astronauts have gone before, they must have optimal reflexes, vision and decision-making. In the era of deep space exploration, the brain—without a doubt—is the final frontier.
Swiss researchers have discovered a third type of brain cell that appears to be a hybrid of the two other primary types — and it could lead to new treatments for many brain disorders.
The challenge: Most of the cells in the brain are either neurons or glial cells. While neurons use electrical and chemical signals to send messages to one another across small gaps called synapses, glial cells exist to support and protect neurons.
Astrocytes are a type of glial cell found near synapses. This close proximity to the place where brain signals are sent and received has led researchers to suspect that astrocytes might play an active role in the transmission of information inside the brain — a.k.a. “neurotransmission” — but no one has been able to prove the theory.
A new brain cell: Researchers at the Wyss Center for Bio and Neuroengineering and the University of Lausanne believe they’ve definitively proven that some astrocytes do actively participate in neurotransmission, making them a sort of hybrid of neurons and glial cells.
According to the researchers, this third type of brain cell, which they call a “glutamatergic astrocyte,” could offer a way to treat Alzheimer’s, Parkinson’s, and other disorders of the nervous system.
“Its discovery opens up immense research prospects,” said study co-director Andrea Volterra.
The study: Neurotransmission starts with a neuron releasing a chemical called a neurotransmitter, so the first thing the researchers did in their study was look at whether astrocytes can release the main neurotransmitter used by neurons: glutamate.
By analyzing astrocytes taken from the brains of mice, they discovered that certain astrocytes in the brain’s hippocampus did include the “molecular machinery” needed to excrete glutamate. They found evidence of the same machinery when they looked at datasets of human glial cells.
Finally, to demonstrate that these hybrid cells are actually playing a role in brain signaling, the researchers suppressed their ability to secrete glutamate in the brains of mice. This caused the rodents to experience memory problems.
“Our next studies will explore the potential protective role of this type of cell against memory impairment in Alzheimer’s disease, as well as its role in other regions and pathologies than those explored here,” said Andrea Volterra, University of Lausanne.
But why? The researchers aren’t sure why the brain needs glutamatergic astrocytes when it already has neurons, but Volterra suspects the hybrid brain cells may help with the distribution of signals — a single astrocyte can be in contact with thousands of synapses.
“Often, we have neuronal information that needs to spread to larger ensembles, and neurons are not very good for the coordination of this,” researcher Ludovic Telley told New Scientist.
Looking ahead: More research is needed to see how the new brain cell functions in people, but the discovery that it plays a role in memory in mice suggests it might be a worthwhile target for Alzheimer’s disease treatments.
The researchers also found evidence during their study that the cell might play a role in brain circuits linked to seizures and voluntary movements, meaning it’s also a new lead in the hunt for better epilepsy and Parkinson’s treatments.
“Our next studies will explore the potential protective role of this type of cell against memory impairment in Alzheimer’s disease, as well as its role in other regions and pathologies than those explored here,” said Volterra.