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Health and Fitness, Neuroscience, Research

Regularly practicing hatha yoga may improve brain function for older adults

77878_webPast studies have suggested that practicing yoga can help those suffering from insomnia rest easier and boost the immune system. Now new research shows that regularly participating in hatha yoga, which emphasizes physical postures and breath control, may improve older adults’ cognitive function.

In a study (subscription required) involving more than 100 adults ages 55 to 79, researchers assigned roughly half of the individuals to attend hatha yoga classes three times a week for eight weeks while the others participated in sessions in which they engaged in stretching and toning exercises. The Huffington Post reports:

At the end of eight weeks, the group that did yoga three times a week performed better on cognitive tests than it had before the start of yoga classes.

The group that did stretching and toning displayed no significant change in cognitive performance over time. In addition, researchers say the differences seen between the groups were not the result of age, gender, social status or other similar factors.



Edward McAuley
, PhD, who co-led the study, noted that participants in the yoga group displayed significant improvements in working memory capacity. “They were also able to perform the task at hand quickly and accurately, without getting distracted,” he said in a press release. “These mental functions are relevant to our everyday functioning, as we multitask and plan our day-to-day activities.”

Previously: Stanford researchers use yoga to help underserved youth manage stress and gain focus, Third down and ommm: How an NFL team uses yoga and other tools to enhance players’ well-being, Yoga classes may boost high-school students’ mental well-being and Study shows yoga may improve mood, reduce anxiety
Photo by Neha Gothe

From August 11-25, Scope will be on a limited publishing schedule. During that time, you may also notice a delay in comment moderation. We’ll return to our regular schedule on August 25.

Applied Biotechnology, Bioengineering, Cardiovascular Medicine, Neuroscience, Research, Stanford News, Stroke

Targeted stimulation of specific brain cells boosts stroke recovery in mice

big blue brainThere are 525,949 minutes in a year. And every year, there are about 800,000 strokes in the United States – so, one stroke every 40 seconds. Aside from the infusion, within three or four hours of the stroke, of a costly biological substance called tissue plasminogen activator (whose benefit is less-than-perfectly established), no drugs have been shown to be effective in treating America’s largest single cause of neurologic disability and the world’s second-leading cause of death. (Even the workhorse post-stroke treatment, physical therapy, is far from a panacea.)

But a new study, led by Stanford neurosurgery pioneer Gary Steinberg and published in Proceedings of the National Academy of Sciences, may presage a better way to boost stroke recovery. In the study, Steinberg and his colleagues used a cutting-edge technology to directly stimulate movement-associated areas of the brains of mice that had suffered strokes.

Known as optogenetics – whose champion, Stanford psychiatrist and bioengineer Karl Deisseroth, co-authored the study – the light-driven method lets investigators pinpoint a specific set of nerve cells and stimulate only those cells. In contrast, the electrode-based brain stimulation devices now increasingly used for relieving symptoms of Parkinson’s disease, epilepsy and chronic pain also stimulate the cells’ near neighbors.

“We wanted to find out whether activating these nerve cells alone can contribute to recovery,” Steinberg told me.

As I wrote in a news release  about the study:

By several behavioral … and biochemical measures, the answer two weeks later was a strong yes. On one test of motor coordination, balance and muscular strength, the mice had to walk the length of a horizontal beam rotating on its axis, like a rotisserie spit. Stroke-impaired mice [in which the relevant brain region] was optogenetically stimulated did significantly better in how far they could walk along the beam without falling off and in the speed of their transit, compared with their unstimulated counterparts. The same treatment, applied to mice that had not suffered a stroke but whose brains had been … stimulated just as stroke-affected mice’s brains were, had no effect on either the distance they travelled along the rotating beam before falling off or how fast they walked. This suggests it was stimulation-induced repair of stroke damage, not the stimulation itself, yielding the improved motor ability.

Moreover, levels of some important natural substances called growth factors increased in a number of brain areas in  optogenetically stimulated but not unstimulated post-stroke mice. These factors are key to a number of nerve-cell repair processes. Interestingly, some of the increases occurred not only where stimulation took place but in equivalent areas on the opposite side of the brain, consistent with the idea that when we lose function on one side of the brain, the unaffected hemisphere can step in to help restore some of that lost function.

Translating these findings into human trials will mean not just brain surgery, but also gene therapy in order to introduce a critical light-sensitive protein into the targeted brain cells. Steinberg notes, though, that trials of gene therapy for other neurological disorders have already been conducted.

Previously: Brain sponge: Stroke treatment may extend time to prevent brain damage, BE FAST: Learn to recognize the signs of stroke and Light-switch seizure control? In a bright new study, researchers show how
Photo by Shutterstock.com

From August 11-25, Scope will be on a limited publishing schedule. During that time, you may also notice a delay in comment moderation. We’ll return to our regular schedule on August 25.

Bioengineering, Stanford News

Foldscope inventor named one of the world’s top innovators under 35 by Technology Review

Foldscope inventor named one of the world's top innovators under 35 by Technology Review

Stanford bioengineer Manu Prakash, PhD, has said that he wants to make high-tech science available to the developing world. This year, his “frugal science” approach has earned him considerable media attention, culminating in today’s announcement that he has been named one of Technology Review’s 35 innovators under 35 (Prakash is 34).

Prakash’s busy year got its start in the spring, when a TED talk he had given about a 50 cent folding microscope was released. The microscope, called the Foldscope, folds like origami and is powerful enough to detect microbes and project the image on a wall or screen. Prakash later offered to give away 1,000 Foldscopes to people carrying out innovative projects around the world.

Soon after, Prakash won a competition to build a new science kit for kids, held by the Gordon and Betty Moore Foundation and the Society for Science & the Public. His entry was a sophisticated chemistry kit built out of a music box. In a story I wrote, Prakash said, “I’d started thinking about this connection between science education and global health. The things that you make for kids to explore science are also exactly the kind of things that you need in the field because they need to be robust and they need to be highly versatile.”

These accomplishments earned Prakash an invitation to the White House Makers Faire in June, where National Institutes of Health Director Francis Collins, MD,  PhD, had a chance to try the Foldscope. He wrote about the device in his blog, “Not only will Foldscope give healthcare workers around the globe better ways to detect, and thereby treat, disease, it will also place magnifying power within the reach of all the world’s students, enabling them to ask and answer a great many scientific questions.”

Technology Review described what made Prakash stand out:

Manu Prakash is determined to push down the cost of doing science. Expensive facilities, he says, limit knowledge and expertise to a privileged elite. So from his lab in Stanford’s bioengineering department, he’s producing instruments that enable people to undertake scientific explorations on the cheap.

Previously: Manu Prakash on how growing up in India influenced his interests as a Maker and entrepreneur, Dr. Prakash goes to Washington, The pied piper of cool science tools, Music box inspires a chemistry set for kids and scientists in developing countries and Free DIY microscope kits to citizen scientists with inspiring project ideas

From August 11-25, Scope will be on a limited publishing schedule. During that time, you may also notice a delay in comment moderation. We’ll return to our regular schedule on August 25.

History, In the News, Stanford News

Remembering Kenyan statesman and Stanford medical school alumnus Njoroge Mungai

Remembering Kenyan statesman and Stanford medical school alumnus Njoroge Mungai

MungaiOn a visit to Kenya in 2005, I spent an extraordinary afternoon with Njoroge Mungai, MD, one of the country’s elder statesmen and a 1957 graduate of Stanford medical school. It was one of the most memorable experiences of that trip, so it was with bittersweet sentiment that I learned over the weekend that Mungai had passed on at the age of 88.

Mungai was one of the founders of modern Kenya and served the young East African country in many leadership capacities, including ministers of defense, foreign affairs, health and environment and natural resources. He helped establish the nation’s regional health care system, as well as its first medical school, which is based at the University of Nairobi.

I met Mungai on a trip to Kenya with my longtime friend and documentary photographer Karen Ande, in which we were interviewing families and children affected by AIDS. We had just spent several days with orphaned teens who were taking care of young siblings in a gritty slum neighborhood of Nairobi.

We then headed to the outskirts of the capital city to Mungai’s 45-acre estate, where he was growing roses for export. We were greeted in the expansive foyer by a stuffed lion as Mungai, a slim dapper man in a grey suit, arrived from a side door, his cane quietly tapping the floor.

We had expected perhaps an hour of his time for an interview for Stanford Medicine magazine, but it stretched well into the afternoon. After drinks on the patio, he invited us to a sumptuous buffet in a room peppered with photos of him with some of the world’s great leaders of the time.

With the air and caution of a diplomat, he told us stories of his life – from his humble beginnings as the son of a cook to his schooling in South Africa and the United States and his leadership in the revolution that led to the establishment of the Kenyan nation in 1963.

A cousin of the first Kenyan President Jomo Kenyatta, Mungai was particularly proud of his role in helping Kenya maintain a neutral stance while the world powers were creating chaos in neighboring countries in their eagerness to carve out their positions in Africa. He was also proud of his work in bringing the United Nations Environment Program to Kenya, the only country outside the West where the world organization has a presence.

We left him in the fading light of day with four dozen beautiful roses, a gift from a very gracious man.

Photo by Karen Ande

From August 11-25, Scope will be on a limited publishing schedule. During that time, you may also notice a delay in comment moderation. We’ll return to our regular schedule on August 25.

Podcasts, Stanford News

The amazing photographer Max Aguilera-Hellweg

The amazing photographer Max Aguilera-Hellweg

I had heard from Rosanne Spector, the editor of Stanford Medicine, that our design team had hired an East Coast photographer to shoot for the current surgery issue. It’s surgery, so of course we wanted vibrant pictures that tell their own story. But not until I interviewed Max Aguilera-Hellweg for this 1:2:1 podcast did I realize what an extraordinary photographer we hired and what an an amazing career he’s had to boot.

At 18, Aguilera-Hellweg apprenticed with famed Rolling Stone photographer Annie Liebovitz. Over the years, he’s shot photos for a multitude of international publications including Stern, Rolling Stone, The New Yorker, Esquire, the Washington Post, National Geographic and The New York Times. And he has one more credit to his name: MD. Yep. He’s a physician. At age 43 he received a medical degree from Tulane University with a specialty in internal medicine. He’s well-equipped to both shoot photos inside the OR and lend a hand in case of an emergency.

We asked Aguilera-Hellweg to shoot a panoply of photos for the issue, and they’re extraordinary. He also shot the cover – one that I think conveys the essence of what surgery is all about: the hands. So listen to this podcast and explore the amazing world of Max Aguilera-Hellweg: photographer, physician, Renaissance man.

Previously: Stanford Medicine magazine opens up the world of surgery

From August 11-25, Scope will be on a limited publishing schedule. During that time, you may also notice a delay in comment moderation. We’ll return to our regular schedule on August 25.

Neuroscience, Pediatrics, Research, Stanford News

Kids’ brains reorganize as they learn new things, study shows

Kids' brains reorganize as they learn new things, study shows

arithmeticWhy do some children pick up on arithmetic much more easily than others? New Stanford findings from the first longitudinal brain-scanning study of kids solving math problems are shedding light on this question. The work gives interesting insight into how a child’s brain builds itself while also absorbing, storing and using new information. It turns out that the hippocampus, already known as a memory center, plays a key role in this construction project.

Published this week in Nature Neuroscience, the research focuses on what’s happening in the brain as children shift from counting on their fingers to the more efficient strategy of pulling math facts directly from memory. To conduct the study, the research team collected two sets of magnetic resonance imaging scans, about a year apart, on a group of grade-schoolers. From our press release:

“We wanted to understand how children acquire new knowledge, and determine why some children learn to retrieve facts from memory better than others,” said Vinod Menon, PhD, the Rachel L. and Walter F. Nichols, MD, professor of psychiatry and behavioral sciences at Stanford and the senior author of the study. “This work provides insight into the dynamic changes that occur over the course of cognitive development in each child.”

The study also adds to prior research into the differences between how children’s and adults’ brains solve math problems. Children use certain brain regions, including the hippocampus and the prefrontal cortex, very differently from adults when the two groups are solving the same types of math problems, the study showed.

“It was surprising to us that the hippocampal and prefrontal contributions to memory-based problem-solving during childhood don’t look anything like what we would have expected for the adult brain,” said postdoctoral scholar Shaozheng Qin, PhD, who is the paper’s lead author.

The study found that as children aged from an average of 8.2 to 9.4 years, they counted less and pulled facts from memory more when solving math problems. Over the same period, the hippocampus became more active and forged new connections with other parts of the brain, particularly several regions of the neocortex. But comparison groups of adolescents and adults were found on brain scans not to be making much use of the hippocampus when solving math problems. In other words, Menon told me, “The hippocampus is providing a scaffold for learning and consolidating facts into long-term memory in children.” And the stronger the scaffold of connections in an individual child, the more readily he or she pulled math facts from memory.

Now that the scientists have a baseline understanding of how this brain-building process normally works, they hope to run similar brain-scanning tests on children with math learning disabilities, with the aim of understanding what goes awry in the brains of children who really struggle with math.

Previously: Unusual brain organization found in autistic kids who best peers at math, Peering into the brain to predict kids’ responses to math tutoring and New research tracks “math anxiety” in the brain
Photo by Yannis

From August 11-25, Scope will be on a limited publishing schedule. During that time, you may also notice a delay in comment moderation. We’ll return to our regular schedule on August 25.

Cardiovascular Medicine, Health and Fitness, Medicine and Society, Men's Health, Women's Health

Study questions safety of excessive exercise for heart attack survivors

Study questions safety of excessive exercise for heart attack survivors

Scope runningA recent article in PsychCentral highlighted findings published in the Mayo Clinic Proceedings offering more evidence that extreme exercise for heart attack survivors could put them at a higher risk for a cardiovascular event.

Paul Williams, PhD, staff scientist for the Life Sciences Division of Lawrence Berkeley National Laboratory, and Paul Thompson, MD, a cardiologist at Hartford Hospital, conducted a long-term study looking at the relationship between exercise and cardio-disease related death in about 2,400 physically-active heart attack survivors. The study reported on data taken from the National Walker’s and Runners’ heath studies at Lawrence Berkeley Laboratory.  From the piece:

“These analyses provide what is to our knowledge the first data in humans demonstrating a statistically significant increase in cardiovascular risk with the highest levels of exercise,” say Williams and Thompson.

“Results suggest that the benefits of running or walking do not accrue indefinitely and that above some level, perhaps 30 miles per week of running, there is a significant increase in risk.

Competitive running events also appear to increase the risk of an acute event.”

However, they point out that “our study population consisted of heart attack survivors and so the findings cannot be readily generalized to the entire population of heavy exercisers.”

On the other end of the spectrum, the journal also included research from Spain related to mortality in elite athletes. The investigation included over 42,000 top athletes, of which 707 were women, and examined the beneficial health effects of excessive exercise, particularly in decreasing cardiovascular disease and cancer risk. Senior investigator Alejandro Lucia, MD, PhD, said in the article, “What we found on the evidence available was that elite athletes (mostly men) live longer than the general population, which suggests that the beneficial health effects of exercise, particularly in decreasing cardiovascular disease and cancer risk, are not necessarily confined to moderate doses.”

With the majority of Americans still at risk for obesity, cardiovascular disease and diabetes, regular moderate exercise is still recommended by these researchers. As Hippocrates, the father of medicine, once said, “Everything in excess is opposed to nature.”

Previously: Study reveals initial findings on health of most extreme runners, The exercise pill: A better prescription than drugs for patients with heart problems?, Examining how prolonged high-intensity exercise affects heart health and Study reveals initial findings on health of most extreme runners
Photo by: Matthias Weinberger

From August 11-25, Scope will be on a limited publishing schedule. During that time, you may also notice a delay in comment moderation. We’ll return to our regular schedule on August 25.

Events, Medicine X, Stanford News, Technology

Countdown to Medicine X: Global Access Program provides free webcast of plenary proceedings

Countdown to Medicine X: Global Access Program provides free webcast of plenary proceedings

Those unable to physically attend next month’s Stanford Medicine X conference can participate in the event through the Global Access Program, which brings high-quality streaming video of the conference plenary proceedings, live photos and other updates to viewers’ desktop or mobile device. More details on the webcast can be found on the Medicine X blog:

The Global Access team is led by Emmy-award winning television producer Bita Nikravesh Ryan and 2013 Stanford-NBC Global Health Media fellow Hayley Goldbach. Our photography team includes Academy Award-winning documentary filmmaker Theo Rigby, speaker portrait photographer Christopher Kern, and our special venues photographer Yuto Wantanabe.

This year’s Global Access team also welcomes inventor and cancer researcher Jack Andraka.

To participate in the program, you will need to register on the conference website.  Keep in mind that the live stream does not include coverage of breakout sessions, pre-conference workshops, Master Classes or the IDEO Design Challenge.

Previously: Countdown to Medicine X: How to engage with the “no smartphone” patient, Medicine X symposium focuses on how patients, providers and entrepreneurs can ignite innovation and Medicine X spotlights mental health, medical team of the future and the “no-smartphone” patient

From August 11-25, Scope will be on a limited publishing schedule. During that time, you may also notice a delay in comment moderation. We’ll return to our regular schedule on August 25.

Behavioral Science, Neuroscience, Research

Why memories of mistakes may speed up learning

Why memories of mistakes may speed up learning

mistake_learningRemember when you burnt the crab cakes on one side while testing a new recipe for a dinner party and had to compensate by generously dressing them with a creamy sauce? What about the time you were introduced to a friend’s new girlfriend, whose name was somewhat similar to the last one, and you called her the wrong name? Or that accidental trip down a one-way street while in an unfamiliar city? Chances are you didn’t make these mistakes twice.

Now findings (subscription required) published today in Science Express may explain how memories of past errors speed learning of subsequent similar tasks. As explained in a release, scientists have known that when performing a task, the brain records small differences between expectation and reality and uses this information to improve next time. For example, if you’re learning how to drive a car the first time you may press down on the accelerator harder than necessary when shifting from the break pedal. Your brain notes this and next time you press down with a lighter touch. The scientific term for this is “prediction errors,” and the process of learning is largely unconscious. What’s surprising about this latest study is “that not only do such errors train the brain to better perform a specific task, but they also teach it how to learn faster from errors, even when those errors are encountered in a completely different task. In this way, the brain can generalize from one task to another by keeping a memory of the errors.”

To arrive at this conclusion, researchers used a  simple set of experiments where volunteers were placed in front of joystick that was hidden under a screen. More from the release:

Volunteers couldn’t see the joystick, but it was represented on the screen as a blue dot. A target was represented by a red dot, and as volunteers moved the joystick toward it, the blue dot could be programmed to move slightly off-kilter from where they pointed it, creating an error. Participants then adjusted their movement to compensate for the off-kilter movement and, after a few more trials, smoothly guided the joystick to its target. In the study, the movement of the blue dot was rotated to the left or the right by larger or smaller amounts until it was a full 30 degrees off from the joystick’s movement. The research team found that volunteers responded more quickly to smaller errors that pushed them consistently in one direction and less to larger errors and those that went in the opposite direction of other feedback.

Daofen Chen, PhD, a program director at the National Institute of Neurological Disorders and Stroke, commented on the significance of the findings saying, “This study represents a significant step toward understanding how we learn a motor skill … The results may improve movement rehabilitation strategies for the many who have suffered strokes and other neuromotor injuries.”

Previously: Depression, lifestyle choices shown to adversely affect memory across age groups, Newly identified protein helps explain how exercise boosts brain health and Exercise may protect aging brain from memory loss following infection
Photo by Grace

From August 11-25, Scope will be on a limited publishing schedule. During that time, you may also notice a delay in comment moderation. We’ll return to our regular schedule on August 25.

Medicine and Literature, Stanford News, Surgery

The operating room: long a woman’s domain

The operating room: long a woman’s domain

In my recent story for Stanford Medicine magazine on the transformational changes in surgery, I reported that “women were once personae non gratae in the operating room.” An alumna of the medical school, Judith Murphy, MD, took me to task for my choice of words, for as she points out, women have long been the backbone of the OR.

“In fact, for decades, women outnumbered men in the OR – circulating nurse, scrub nurse, overseeing nurse, etc.,” she wrote to me. “So it is not that there were no women in the OR, but there were no women surgeons. No Women Who Count, although everyone knows these nurses are essential to successful surgery.”

When she was a medical student at Stanford in the early 1970s, she says female students and faculty had to use bathrooms and lockers that were labeled “Nurses,” whereas the men’s room was labeled, “Doctors.”

“We all laughed about it, but it did reflect the unconscious assumptions that your language still perpetuates, all these years later and after so much progress,” she shared with me. “The women who came after us were a bit more empowered and did not think it was funny; they complained, and the doors were changed to Men and Women.”

Murphy, a practicing pediatrician in Palo Alto for decades, says she might not have made note of the issue were it not for a recent encounter with a male acquaintance who, on learning she was connected to Stanford Hospital, said, “I never knew you were a nurse.”

“When he said that, I thought, ‘Darn, I can’t believe this is still happening.’ I gave him my usual response: ‘I have great respect for nurses and could never have done as good a job without them, but in fact, I’m a doctor,’” said Murphy, who is now retired.

“The power of the cultural unconscious assumption remains strong, even here where we have come so far,” she wrote. “This has been happening to me occasionally for 40 years, less so lately. I had hoped it would become archaic.”

Murphy says her response may have been a bit testier than in the past. But she can be excused, for it is always good to be reminded of our unconscious biases about the role of women in health care, reflected both in our language and behavior.

Previously: Surgery: Up close and personal and Stanford Medicine magazine opens up the world of surgery

From August 11-25, Scope will be on a limited publishing schedule. During that time, you may also notice a delay in comment moderation. We’ll return to our regular schedule on August 25.

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