by  Norman  Doidge, M.D.

Rewiring a Brain with Light

Using Light to Reawaken Dormant Neural Circuits

It is the unqualified result of all my experience with the sick, that second only to their need of fresh air is their need of light; that, after a close room, what hurts them most is a dark room, and it is not only light but direct sun-light that they want People think that the effect is upon the spirits only. This is by no means the case. The sun is not only a painter but a sculptor.

Florence Nightingale, Notes on Nursing, 1860

A Small World

This story, of two chance encounters with a stranger, occurred within the space of a city block. The first took place at a small medical auditorium only steps from my office, to the east. The second happened in beautiful Koerner Hall, at the Royal Conservatory of Music, a few steps to the west.

In the late autumn of 2011, the Ontario Medical Association sent a playful notice to Ontario's doctors. We had a small society, the Doctor's Lounge, that met once a month in Toronto for dinner, followed by a lecture at association headquarters. The Doctor's Lounge functioned within the province's largest mainstream medical organization. Lounge members were of all ages, from very young to retired, companions in that we all had a taste for talks on the cutting edge of medicine and science.

Once there was a doctor's lounge in every hospital, where surgeons in scrubs and hair bonnets, or physicians after a long day on the wards, would, in a rare and lyrical mood, unwind with unguarded conversation, talk about their shared patients, and discuss the latest news in science and medicine. The lounge was a space with a nineteenth-century feel. But in a hurried age, as modern managers, administrators, and "efficiency experts" made sure there would be no "lounging," the lounges began to disappear from hospitals. So we, in defiance, resurrected the lounge at our association headquarters, as a place to think free-style, with the open-mindedness that first drew us to study medicine and the wonders of the human body.

Even our organizers announcement was unlike the starchy prose of most large organizations, which so often take painstaking care to appear lifeless, as though a deadening formality might better convey seriousness of professional purpose. It was called "From Darkness to Light: Clinical Explorations," and it opened with a quote from the Potzker Rebbe: "And God said: Let there be paradox. And there was light." It read:

What are the properties of light? Wave? Particle? Clinical tool? Yes, yes and yes. The therapeutic applications of light therapy range from the well-established (e.g., neonatal jaundice, psoriasis) to emerging popular trends (e.g., light therapy for seasonal affective disorder), but, chances are you are not aware of effective light therapy options available to your patients for conditions ranging from wound healing to brain injury....

Date and Time: December 8,2011, 7:30 p.m.

The notice continued, explaining that the lecture would emphasize the use of light for brain injury and for other neurological and psychiatric problems.

It gave me pause. Light, to treat brain injury? How might light get into the brain, encased as it is in the bony skull? I had followed the new science of optogenetics, an almost sci-fi field in which labs genetically engineer neurons to make them light-sensitive. In 1979 Francis Crick, codiscoverer of the structure of DNA, argued that the major challenge for neuroscience was to find a way to turn on certain neurons while leaving others unaffected. Perhaps, Crick speculated, light could be used to turn specific classes of neurons on or off.

It was known that some single-cell organisms, such as algae, are light-sensitive; when they are exposed to light, a switch inside them activates the cell. In 2005 genes coding for those light-sensitive switches were inserted into animal neurons, so they could be activated by exposure to light. Some hoped it would be possible to implant these neurons into the brain of a person with a serious brain disease, then surgically thread a fiber-optic line into the damaged brain cells and use light to turn them on or off. This technique had already succeeded in worms, mice, rats, and monkeys, and it seemed possible humans would be next. But this approach is highly invasive, and optogeneticss brilliant pioneer, Karl Deisseroth, a psychiatrist and professor of bioengineering at Stanford University, worried that if we surgically inserted foreign substances such as fiber optics into the human brain, they could cause immune reactions, among other problems. Deisseroth viewed optogenetics as a basic scientific tool to understand how brain circuits work, not as something that would be useful on patients. Perhaps one day the fruits of optogenetics would save lives, but as the day of the lecture approached, I hoped it would present something more practical, a treatment that would heal by working with nature, not against it.

Light Enters Our Bodies Without Our Knowledge

Luckily, light—even natural light—does not require fiber optics and surgery to pass deeply into the brain. We think of our skin and skull as absolute barriers to light, but that is wrong. The energy from normal sunlight passes through the skin to influence the blood, for instance. The lecture notice described using light to cure "neonatal jaundice" as one example. Neonatal jaundice, or yellowing of the skin and eyes, occurs when a newborns liver is immature, not quite ready to perform all its metabolic functions. We are always producing new red blood cells, refreshing our supply; the new ones replace the older ones, which have to be broken down. Neonatal jaundice is caused when a chemical called bilirubin (from the bile), produced by old red blood cells when they break down, builds up in the body. About half of newborns have jaundice. It generally lasts only a few days, but if it persists, it can become a serious condition, and if untreated, it can lead to a buildup of bilirubin in the brain, causing permanent brain damage.

As physicians became better at saving the lives of premature infants, neonatal jaundice became a growing problem. In Essex, England, a former World War II hospital with a sunlit courtyard facing south was devoted to the care of these yellowed fledglings. Sister }. Ward, known for her skill in rearing puppies, was put in charge of the preemies. She often removed the most delicate of them from their incubators and wheeled them out into the fresh air of the sunlit courtyard, though this impulse made some of the staff anxious. However, Wards infants began to improve. One day she undressed one of them and diffidently showed the baby to the physician in charge. Its tummy was no longer yellow in the places that had been exposed to the sun.

No one took her seriously until one day a vial containing a blood sample from a jaundiced baby was accidentally left on a windowsill, in natural sunlight, for several hours. When the sample came back, the blood was normal. The doctors were certain that a mistake had been made. But when Drs. R. H. Dobbs and R. J. Cremer investigated further, they found that the excess bilirubin in the sample had somehow been broken down, or metabolized, so that the blood in the vial now had normal bilirubin levels. Perhaps this explained why Sister Ward's jaundiced babies got better in the sun?

Investigations soon proved that the wavelengths of visible blue light— passing through the babies' skin and blood vessels to reach the blood and perhaps the liver too—had caused this marvelous curative effect. Using light to treat jaundice became mainstream. Sister Ward's chance discovery proved we are not as opaque as we imagine ourselves to be.

In fact, Sister Ward's and Drs. Dobbs and Cremer's discovery had already been made by the ancients, then was lost to modern medicine. Soranus of Ephesus, one of imperial Rome's best-known physicians, advocated setting jaundiced newborns out in the sun. Most pagans took phototherapy very seriously, and "heliotherapy"—as it came to be called by the ancients after Helios, the Greek god of the sun—was seen as so potent that ancient buildings were designed to capture as much pure sunlight as possible. The Romans even had right-to-light laws, to guarantee people's access to the sun in their homes (which led them to develop solariums). Ultimately, these laws ceased to be enforced, and the healing properties of light were almost forgotten.*

Not until Florence Nightingale, the founder of modern nursing, were hospitals designed to expose patients to as much sun as possible. But that brief, sunlight-friendly period in the nineteenth century ended with the invention of the artificial lightbulb, which was believed to contain the same full spectrum of light as direct sun. (Unfortunately, artificial light was neither full-spectrum nor equivalent to natural light.) Hospital designs no longer favored natural light, because science could not explain Nightingale's insight that sunlight actually heals.

The idea that light is a potent healer has been hidden in plain sight for millennia. Though the ancient Egyptians had little science, they did not doubt what they saw with their own eyes: that the sun was essential to growth and life everywhere. They worshipped the sun god Ra—they were literal sun worshippers—and, like most worshippers, had high hopes their god would not only protect but heal them. Ra's presence was everywhere. Even the all-powerful pha-ra-oah had Ra's name embedded in his. The Egyptians and many other ancient pagans saw the sun as the primary source of life, and they took it as self-evident that all life-forms ultimately derive their energy from the sun. (Of course, sunlight is necessary for photosynthesis, the process by which plants convert carbon

* But not entirely. Niels R. Finsen, a Danish physician, won the Nobel Prize in 1903 for pioneering the use of light therapy in modern times, including the red part of the spectrum to treat smallpox. He discovered he was not the first to make the connection. "In the Middle Ages," he wrote, "small-pox patients were treated by wrapping them in red coverings and by putting red balls in their beds. John of Gaddesden treated a Prince of Wales for small-pox by surrounding him with red objects... whilst Dr. Sassakawa reports that in Japan the patients are covered with red blankets, and children with small-pox are given red toys. This remarkable and uncertain employment of the red colour in the treatment of small-pox has naturally been looked upon as a mediaeval superstition." See N. R. Finsen, "The Red Light Treatment of Small-pox," British Medical Journal (December 7,1895), pp. 1412-14.

dioxide and water into glucose, their energy source. Even organisms that do not conduct photosynthesis get their energy from eating plants, or from eating other animals that do so, so ultimately all growth on the planet depends on the sun.)

The ancients also sensed that the healing of distressed tissues requires growth. Ancient Egyptian, Greek, Indian, and Buddhist healers all used systematic exposure to the sun to foster healing. An ancient Egyptian papyrus from the Pharaonic period describes anointing painful, ill body parts with fluids and exposing them to the sun to obtain medical benefits. Thus many recent discoveries about light are actually rediscoveries, such as the finding in 2005 that placing patients recovering from surgery in a sunlit room (as opposed to an artificially lit one) significantly decreases their pain.

In 1984 Dr. Norman Rosenthal, of the National Institutes of Health, discovered that some depressions can be cured by sun exposure, and a recent study showed that a full spectrum of light could be as effective as medication for some depressed patients, with fewer side effects. These ideas were known to the ancient Greeks and Romans. The Greek physician Aretaeus of Cappadocia wrote in the second century, "Lethargies are to be laid out in the light and exposed to the rays of the sun, for the disease is gloom." And if sunlight influences mood, it influences the brain.

Grade-school science tells us light energy enters the eye and hits the retina and the rod and cone cells within it; there it is converted into patterns of electrical energy, which then travel along the neurons in the optic nerves to the brains visual cortex at the back of the head, producing a visual experience.

In 2002 a second pathway from the retina to the brain, with an altogether different purpose, was discovered. Alongside the retinal cells we use for seeing—our rods and cones—other light-sensitive cells were found that send electrical signals on a separate neuronal pathway, also in the optic nerve, to a clump of cells in the brain called the suprachias-matic nucleus (SCN), which regulates our biological clock.

healthy tissue with mental experience—be it exercise, movement, or sensing the world—to reorganize itself and form new connections, and sometimes even to grow new neurons to take over the lost cognitive functions of the damaged tissue. But the limiting factor is that there has to be some healthy tissue to take over from the damaged tissue. I wanted to explore whether light therapy might help to heal brain tissue that was still "sick" in some way. Could it help heal the general cellular function of the neurons? If this was possible, then light would provide a new way to heal brain problems. After the brain cells were normalized, the neurons could be trained to rewire themselves to take over lost mental functions.

As a colleague and I took our dinner from the buffet, sat down, and started to chat with fellow physicians, I saw, across the room, a slim woman with dark hair, Mediterranean features and skin color, glasses, and an intelligent face; she was making careful movements and looking frail. She approached me, deliberately, and began speaking, slowly. She told me I looked familiar, but she was not sure from where, and that she was really bothered that she couldn't figure it out. But before we could sort it out, she said, "I am Gabrielle Pollard." Then I introduced myself. She did not recognize my name, nor I hers.

I was beginning to suspect, from her careful walk—guarded and unsteady—and her slightly slowed speech that she might be struggling with a brain injury. Perhaps she had come to the lecture for very personal reasons. And then the lecture began.

The first speaker was Fred Kahn, a general and vascular surgeon. Slim and fit, Kahn had a white shock of hair that swept across his forehead. Though he appeared to be in his midseventies, he was eighty-two and still worked sixty-plus hours a week. He looked as if he got his share of sun—especially compared with the audience members, who were mostly younger, pale-faced, skin-cancer-wary heliophobes who knew the sun could be dangerous but had forgotten that human life could not have evolved without its rays. Kahn made a point of getting four hours of healthy sun during the week, and more on weekends. He swam four times a week and went for long walks in the fresh air. He wore casual attire, but he looked as though he would have been more comfortable in scrubs than dress clothes and couldn't stand the feeling of a necktie. He had the mild, flat, dry, matter-of-fact drawl of someone raised in rural Ontario, into which he packed his story, his irony, and a few deadpan asides.

Kahn, as I was to learn later, had been born in Germany in 1929 into a Jewish family. He had lived through Kristallnacht, November 9-10, 1938, when the Nazis set nearly all of Germany's synagogues on fire and put thirty thousand Jews in concentration camps. Three weeks before World War II broke out, his family made a daring nighttime escape by car and train, bribing German officials to cross into Holland, leaving all their possessions behind. The Kahns ultimately moved to Uxbridge, Ontario, becoming farmers. Fred was raised on a farm and went to a little red schoolhouse, trudging six miles in the snow each winter day to get himself there and back. As a boy, he worked for hours in the summer sun with his shirt off. He started driving a Fordson tractor, quite illegally, when he was ten, and he developed a farmer's virtues, becoming ever mindful of nature, its dictates, majesty, harshness, and power.

He won a scholarship to medical school at the University of Toronto. When he graduated, unimpressed with the drugs that internists prescribed, he became a general surgeon and ultimately chief surgeon at a huge mining operation in northern Ontario. With his extraordinary energy, he replaced four other surgeons at the mining hospital and ran two operating rooms around the clock. He went to Massachusetts General Hospital to study vascular surgery, then to Texas to study at Baylor with one of the finest surgeons in the world, Denton Cooley, who performed one of the first heart transplants. In California he practiced vascular and general surgery, operating on abdominal aneurysms, doing bypass procedures, and clearing clogged carotid arteries. He was a consulting surgeon to the U.S. military. As lead physician he went on to establish a 250-bed hospital, becoming chief of staff and then chair of the department of surgery. In those years, he performed over twenty thousand major surgical procedures.

"I got into lasers, over twenty years ago," he told us, beginning his lecture, "because I was an avid skier and had damaged my shoulder, and it had become a chronic problem." He had skied the great mountains, including the Alps, and got a serious rotator cuff injury. For two years it had been difficult to do any physical activity, let alone ski. Steroid injections didn't help. "My surgeons said, 'You are going to need surgery on that shoulder.' And I thought, 'I am a surgeon. And I know what they are going to do to that shoulder, how they are going to cut it up, and I know the likely poor results. No thanks.'" So he suffered, until one day a chiropractor he knew said to him, "Why don't you try my Russian laser?"

The chiropractor had an old Russian machine. It was 1986, and the Cold War was still on, but a few of these simple contraptions had made their way to the West. So Kahn let the man use the equipment on him, and in five sessions the shoulder that had been aching and stiff for two years was cured. The laser was a low-intensity laser, not the "hot" high-intensity kind that can burn through flesh.

Kahn was intrigued. When he reviewed the scientific literature, he found that these low-intensity laser treatments worked by helping the body marshal its own energy and its own cellular resources to heal itself, with no side effects. Lasers, it seemed, could treat a number of conditions that nothing else could and could decrease the need for medication or surgery. He was so intrigued that even though he was at the top of his game as a surgeon, he gave it all up to study lights.

Low-intensity laser therapy—largely unknown to mainstream practitioners—is based on a scientific literature of more than three thousand publications and more than two hundred clinical trials with positive results. Most of the early studies were done in Russia or in eastern Europe—countries closer to China, Tibet, and India. Because the East was generally more interested in the role of energy in medicine, the earlier studies remained relatively unknown in the West.

Much of Kahn's lecture that night in 2011 was about the science of light and how lasers work to stimulate healing at a cellular level. He explained the difference between the two kinds of lasers. Lasers that burn are high-intensity lasers (or hot or thermal lasers). They can destroy flesh and are used in surgery to cut away diseased tissue. Low-intensity lasers (also called soft lasers, or cold lasers, or low-level lasers)—the only ones Kahn used—promote healing. They give off little or no heat and work by producing changes in cells, mostly by helping sick cells to energize and heal themselves.

Normal light energy is one part of the huge electromagnetic spectrum, which includes many kinds of waves, each with different wavelengths—including radio waves, X-rays, microwaves—most of which we cannot see with the naked eye. But we can see wavelengths of 400 to 700 nanometers. (A nanometer is one billionth of a meter.) Visible light, from one end of the spectrum to the other, consists of violet (400 nanometers), which contains the most energy, then indigo, blue, green, yellow, orange, and finally red (700 nanometers), which has the least energy. Natural light is a mixture of all these wavelengths. The frequency most often used for laser healing is red light, at a wavelength of 660 nanometers. But infrared light is also used typically at highly specific wavelengths of 840 or 830 nanometers; they cant be seen with the naked eye because they fall outside the visible range. (The idea of "invisible light" may seem counterintuitive, but it, too, is light and consists of photons and light energy. Night-vision goggles, used by special forces to "see" in the dark, collect infrared light, which humans normally cannot see, and amplify it.)

A unique characteristic of lasers is that they can produce light of unrivaled purity, meaning a wavelength accurate to a single nanometer. Lasers are thus said to be monochromatic, of a single color. A laser can produce a light beam that is, for example, 660 nanometers, or 661, or 662, and so on. With low-intensity lasers, precision is key, because sometimes a particular wavelength will help tissue heal, but a slightly different wavelength will not.

Another characteristic of lasers is that they can direct their beam in a single direction, and their light energy can be concentrated in that narrow beam. Most light sources, such as incandescent bulbs or the sun (natural light), produce light that disperses over distance.

A further characteristic is the intensity of laser light. A 100-watt lightbulb, seen from thirty centimeters away, will shed only a thousandth of a watt of energy on your eye. But a one-watt laser is thousands of times more intense than a 100-watt bulb. These characteristics give lasers their focus, compared with natural light (which is why we say someone has a "laserlike focus"). A laser pointer can produce a pencil-thin beam that remains concentrated when it falls on its distant target. Such lasers can be aimed by astronomers at the heavens to pinpoint stars.

When the theoretical portion of his presentation was over, Kahn showed his before-and-after slides, and almost everyone was astonished.

His slides showed people with wounds so serious that the skin was unable to close over them, and bones and muscle were sticking out. Many of these patients had remained with open festering wounds for over a year, and all known treatments had failed. Some had been told by their doctors that their limbs would have to be amputated. However, after a few laser treatments, the body started healing those wounds, and over the following weeks, the wounds closed. Kahn showed slides of people with incurable diabetic ulcers, open gashes from car accidents, terrible herpes infections, shingles, horrendous burns, disfiguring psoriasis, appallingly severe eczema—which would not heal with standard medical treatment but were healed with laser light. Unsightly scars called keloids could also be improved, as could the normal sagging wrinkles of aging, because lasers trigger the development of collagen tissue.

Other slides showed black, gangrenous limbs, dying from severe atherosclerosis (poor blood supply) or frostbite, that were saved from amputation with lasers—they had returned to a healthy plump pink. As a vascular surgeon, Kahn had frequently been called upon to try to rescue gangrenous or infected limbs, and wounds that wouldn't heal by transplanting blood vessels from one part of the body to the dying limb. Now he rescued them with light. All these problems had occurred because these patients' bodies were unable to supply their damaged tissues with blood. As a vascular surgeon, he knew good circulation is always necessary for the body to heal itself. But improving circulation is only one of many ways lasers help.

He showed slides of conditions that had been unexpectedly healed by light: torn hamstrings, ripped Achilles tendons, and even degenerative osteoarthritis, which occurs when cartilage wears away. Cartilage acts like a pillow between our joints, but as osteoarthritis develops, the cartilage disappears, leaving bone scraping on bone and causing tremendous inflammation and pain. For decades, medical schools have taught that once cartilage is lost, it can't be replaced, so conventional treatment for osteoarthritis is to give patients painkillers, which are often addictive, and anti-inflammatory drugs, which have significant adverse effects over the long term.* And for osteoarthritis they must be given long term, because they alleviate symptoms but don't cure the disease.

Yet here were pictures of patients whose cartilage had been regenerated by laser therapy. Kahn cited reliable studies showing that lasers trigger regrowth of normal cartilage in animals with osteoarthritis and also increase the number of cartilage-producing cells. Low-level lasers have also recently been shown, in several randomized, controlled studies, to be effective in treating osteoarthritis in humans.

Kahn also showed cases of people with rheumatoid arthritis, including the severe juvenile form, who got better with lasers. A seventeen-year-old girl who had juvenile rheumatoid arthritis since age thirteen made major improvements. In twenty-eight treatments her unusable, deformed, sausagelike fingers, which she couldn't close, re-formed themselves into normal hands that she could use. Astonishingly, people with herniated discs, when treated with lasers, were healed, the body somehow restoring those discs. Lasers helped various pain syndromes and fibromyalgia. People whose immune systems were so suppressed that their feet had been infested with warts and looked like stubs of cauliflower were healed. All sorts of sports injuries to knees, hips, and shoulders, as well as repetitive strain injuries, responded. Patients were able to avoid knee and hip joint surgery. And in passing, Kahn said that there were now positive results in the treatment of traumatic brain injury, some psychiatric disorders, and nerve injuries.

During the lecture Gabrielle, who was sitting behind me, fidgeted and got up and left several times. She had difficulty holding up her head and seemed overwhelmed by the sounds, the flashing slides of open

*In the United States, more than 16,500 people die each year from these drugs, which cause gastrointestinal bleeding—more than die from AIDS. M. M. Wolfe et al., "Gastrointestinal Toxicity of Nonsteroidal Anti-Inflammatory Drugs," New England Journal of Medicine 340, no. 24 (1999): 1889.

wounds. As I was soon to learn, she was not a physician and so was not desensitized to them.

The second speaker, Anita Saltmarche, focused specifically on studies of light therapy used for traumatic brain injury, stroke, and depression. Saltmarche is a registered nurse with a research background and became active in light therapy while working with an Ontario laser company. She got interested in the use of light for the brain when a chiropractor, who had attended her full-day training session, called to consult her on a laser case. The chiropractor was working on a professor, a woman with a Mensa-level IQ, who seven years before had been in a car accident. While she was stopped at a red light, she had been rear-ended by a vehicle going fifty-five miles an hour. Her knee smashed up against the dash, leaving her with arthritis. Her head had lurched forward and back, giving her whiplash and a traumatic brain injury.

Her brain injury symptoms were typical and disabling. She could no longer concentrate or sleep. If she spent more than twenty minutes on the computer, she would be exhausted and unable to focus. She couldn't complete tasks, to the point that she had to quit her job. When she tried to speak, the right words wouldn't come to her, and she lost her ability to speak two foreign languages. She developed angry outbursts and felt deep anguish at all she had lost. After her second attempt at conventional neurorehabilitation failed to improve her functioning, she attempted suicide.

She actually went to the chiropractor for laser treatment of her arthritic knee and was quickly helped. Then she asked whether the light, which had so helped her knee, might also be used on her head.

The chiropractor, before proceeding, asked Saltmarche for her opinion about the safety of shining the lights on the woman's head. "There was an almost forty-year history of low-level laser therapy being safe and having no significant side effects," said Saltmarche, so she thought it would be safe. Knowing which brain areas were involved in the woman's cognitive deficits, Saltmarche suggested eight areas on her head on which to focus the lights. The lights used were not lasers proper but LED lights, in the red and infrared range, which have some laserlike properties.

After the woman received her first treatment, she slept eighteen hours—her first sound sleep since the accident. Then she began improving significantly. She was able to work again, to spend hours on her computer, and even to start her own company. Her foreign languages began to come back. Her depression lifted—though she was still easily frustrated when she tried to multitask, the only area that was still challenging. She also found she had to continue treatment to maintain her improvements, and when she stopped (as she did when she had a terrible flu one time, and a fall another time), her symptoms returned. "Interestingly," said Saltmarche, "when she started her treatments back up again after the 'light holiday,' she improved from her previous level." Her physicians acknowledged her improvement, but couldn't believe light therapy was responsible.

Saltmarche told us she was now involved in a study conducted by Dr. Margaret Naeser and colleagues from Harvard, MIT, and Boston University, including Harvard professor Michael Hamblin, a world leader in understanding how light therapy works at the cellular level. Hamblin, at Massachusetts General Hospital's Wellman Center for Photomedicine, specializes in the use of light to activate the immune system in treating cancer and cardiac disease; he was now branching out into its use for brain injuries. Building on lab work that applied laser therapy to the top of the head (transcranial laser therapy), the Boston group had studied its use in traumatic brain injury and found laser treatment helpful. Naeser, a research professor at the Boston University School of Medicine, had done studies using lasers for stroke and paralysis and was one of several pioneers using "laser acupuncture" by placing light on acupuncture points.

For thousands of years, the Chinese have argued that the body has energy channels, called meridians, that give access to the internal organs, and that these channels have access points on the surface of the body, called acupuncture points because they are traditionally stimulated with acupuncture needles. The ancient Chinese knew these points also responded to pressure or heat. In recent years it was discovered that electricity and even laser light could achieve the desired influence on the meridians through the acupuncture points. The lasers harmlessly and painlessly pass light energy into these channels. Naeser was intrigued to learn that in China, acupuncture was routinely used to treat strokes. So she did a complete training in acupuncture and in 1985 went to China, where she saw lasers being used, instead of needles, to treat paralysis in stroke patients. On her return to the United States, she did a study that showed that patients paralyzed by stroke made significant improvements in their movement when lasers were used to stimulate acupuncture points on the face and other areas—if less than 50 percent of the brains movement pathways were found to be destroyed on a brain scan.

One person treated by the Boston group was a high-ranking female military officer on medical disability who had suffered multiple head concussions in the military and from rugby and skydiving accidents. A magnetic resonance imaging (MRI) brain scan showed that part of her brain had actually shrunk from the brain damage. After four months of light treatment, she was able to go off disability and to function—so long as she continued to get light treatment. If she went off it, she regressed. Saltmarche was now participating in a larger U.S. study, with the Boston group, in which both brain injury and stroke patients were recovering lost cognitive functions, sleeping better, and getting control of their feelings, which had often become intense and unpredictable after brain injuries.

Gabrielle Tells Her Story

At the end of the lecture, Gabrielle went over and spoke to Anita Saltmarche, told her about her neurological and cognitive difficulties, and said she'd be pleased to offer herself as a Canadian subject for the U.S. study. Saltmarche said she would look into it.

I lined up to ask Kahn what kind of brain problems he'd used lasers for—since he hadn't given details. While I was waiting in the line, Gabrielle came over to me with an elderly gentleman, whom she introduced as her father, Dr. Pollard; he was bespectacled, with a delicate,