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Behavioral Science, Big data, Neuroscience, Research, Stanford News

What were you just looking at? Oh, wait, never mind – your brain’s signaling pattern just told me

What were you just looking at? Oh, wait, never mind - your brain's signaling pattern just told me

headI’ve blogged previously (here, here and here) about scientific developments that could be construed, to some degree, as advancing the art of mind-reading.

And now, brain scientists have devised an algorithm that spontaneously decodes human conscious thought at the speed of experience.

Well, let me qualify that a bit: In an experimental study published in PLOS Computational Biology, an algorithm assessing real-time streams of brain-activity data was able to tell with a very high rate of accuracy whether, less than half a second earlier, a person had been looking at an image of a house, an image of a face or neither.

Stanford neurosurgical resident Kai Miller, MD, PhD, along with colleagues at Stanford, the University of Washington and the Wadsworth Institute in Albany, NY, got these results by working with seven volunteer patients who had recurring epileptic seizures. These volunteers’ brain surfaces had already been temporarily (and, let us emphasize, painlessly) exposed, and electrode grids and strips had been placed over various areas of their brain surfaces. This was part of an exacting medical procedure performed so that their cerebral activity could be meticulously monitored in an effort to locate the seizures’ precise points of origin within each patient’s brain.

In the study, the volunteers were shown images (flashed on a monitor stationed near their bedside) of houses, faces or nothing at all. From all those electrodes emanated two separate streams of data – one recording synchronized brain-cell activity, and another recording statistically random brain-cell activity – which the algorithm, designed by the researchers, combined and parsed.

The result: The algorithm could predict whether the subject had been viewing a face, house, or neither at any given millisecond. Specifically, the researchers were able to ascertain whether a “house” or “face” image or no image at all had been presented to an experimental subject roughly 400 milliseconds earlier (that’s the time it takes the brain to process the image), plus or minus 20 milliseconds. The algorithm correctly nailed 96 percent of all images shown in the experiment. Moreover, it made very few lousy guesses: only one in 25 were rotten calls.

“Although this particular experiment involved only a limited set of image types, we hope the technique will someday contribute to the care of patents who’ve suffered neurological imagery,” Miller told me.

Admittedly, that kind of guesswork gets tougher as you add more viewing possibilities – for instance, “tool” or “animal” images. So this is still what scientists call an “early days” finding: We’re not exactly at the point where, come the day after tomorrow, you’re walking down the street, you randomly daydream about a fish for an eighth of a second, and suddenly a giant billboard in front of you starts flashing an ad for smoked salmon.

Not yet.

Previously: Mind-reading in real life: Study shows it can be done (but they’ll have to catch you first), A one-minute mind-reading machine? Brain-scan results distinguish mental states and From phrenology to neuroimaging: New finding bolsters theory about how brain operates
Photo by Kai Miller, Stanford University

Biomed Bites, Research, Stanford News, Videos

Study of ion channels could improve care for osteoporosis

Study of ion channels could improve care for osteoporosis

Welcome to Biomed Bites, a weekly feature that introduces readers to some of Stanford’s most innovative biomedical researchers. 

Ion channels are similar to very sophisticated dog doors. They’re specific, only allowing beloved Fido, not Rover from next door, to enter the house (cell).

And they play an integral role in the electrical signaling that underlies a variety of fundamental physiological processes. Merritt Maduke, PhD, associate professor of molecular and cellular physiology, studies these channels and in the video above, she lays out the puzzles that motivated her to study ion channels, and their kin, ion transporters. (In the dog door analogy, transporters are a door that propels Fido outdoors when he’s feeling lazy). She says:

My interest in ion channels and transporters stems from the molecules themselves. How do they reside in the greasy, thin film of the membrane while at the same time making an aqueous pore that allows ions to cross that barrier? How do they select for certain ions over others? How are they regulated? How do they harvest energy using molecular motions to pump ions?

The answers to these questions may allow researchers to improve treatments for osteoporosis, a condition caused by the weakening of bones, which is spurred, in part due to ion channel-mediated acidification, Maduke says.

Learn more about Stanford Medicine’s Biomedical Innovation Initiative and about other faculty leaders who are driving biomedical innovation here.

Previously: Stanford hearing study upends 30-year-old belief on how humans perceive sound, New genetic regions associated with osteoporosis and bone fracture and Pediatrics group issues new recommendations for building strong bones in kids

Ethics, Health Policy, Patient Care

Small number of physicians account for many malpractice claims

Small number of physicians account for many malpractice claims

gavel01-lgA small number of physicians account for a disproportionately large number of malpractice claims in the United States, Stanford medical and law researchers found after examining 10 years of medical data.

The ability to identify these claim-prone physicians early would be invaluable, the researchers write in a paper published today in The New England Journal of Medicine.

David Studdert, ScD, professor of law and of medicine, and Michelle Mello, JD, PhD, professor of law and of health research and policy — who are also core faculty members of Stanford Health Policy — conducted the study in collaboration with researchers from the University of Melbourne, Australia.

The team found that just 1 percent of practicing physicians accounted for 32 percent of paid malpractice claims over a decade. The study also found that claim-prone physicians had a number of distinctive characteristics. Studdert, lead author of the study, explains:

The degree to which the claims were concentrated among a small group of physicians was really striking. But the fact that these frequent flyers looked quite different from their colleagues — in terms of specialty, gender, age, and several other characteristics — was the most exciting finding. It suggests that it may be possible to identify problem physicians before they accumulate troubling track records, and then do something to stop that happening.

Male physicians had a 35 percent higher risk of recurring claims than female physicians, and the risk of recurrence among physicians younger than 35 years old was about one-third the risk among their older colleagues, the study found.

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Genetics, Immunology, Microbiology, Research, Stanford News

Special delivery: Discovery of viral receptor bodes better gene therapy

Special delivery: Discovery of viral receptor bodes better gene therapy

8565673108_28e017bf50_zGene therapy, whereby a patient’s disorder is treated by inserting a new gene, replacing a defective one, or disabling a harmful one, suffered a setback in 1999, when Jesse Gelsinger, an 18-year-old with a genetic liver disease, died from immense inflammatory complications four days after receiving gene therapy for his condition during a clinical trial. It was quite a while before clinical trials in gene therapy resumed.

But what Stanford virologist Jan Carette, PhD, describes as “intense interest” in the field is once again in full bloom. Gene therapies for several inherited genetic disorders have been approved in Europe, and a gene-therapy approach for countering congenital blindness is close to approval in the United States.

That a virologist would be paying such close attention to this topic isn’t odd, as the most well-worked-out method for introducing genetic material to human cells involves the use of a domesticated virus.

If there’s one thing viruses are really good at, it’s infecting cells. Another viral trick is transferring their genes into cellular DNA — it’s part of their modus operandi: hijacking cells’ replicative machinery and diverting it to production of numerous copies of themselves. Scientists have become increasingly adept at taming viruses, tweaking them so they retain their ability to infect cells and insert genes, but no longer contain factors that wreck tissues or taunt the infected victim’s immune system into a rage destructive to virus and victim alike.

Adenovirus-associated virus — ubiquitous in people and not associated with any disease – makes a great workhorse. Properly bioengineered, it can infect all kinds of cells without replicating itself inside of them or triggering much of an immune response, instead obediently depositing medically relevant genes into the infected cells to repair a patient’s defective metabolic, enzymatic, or synthetic pathways.

Figuring out how to tailor this viral servant so it will invade cells more efficiently, or invade some kinds of cells and tissues but not others, would broaden gene therapy’s utility and appeal. In a series of experiments described in a study in Nature, Carette’s group, with collaborators from Oregon Health & Science University and the Netherlands, used a sophisticated method pioneered by Carette to bring that capability a step closer.

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Medicine and Literature, Podcasts, Stanford News

When Breath Becomes Air: A conversation with Lucy Kalanithi

When Breath Becomes Air: A conversation with Lucy Kalanithi


Kalanithis - bigA few months before he died, I interviewed Paul Kalanithi, MD, for a 1:2:1 podcast about a gorgeous article he wrote for Stanford Medicine entitled “Before I Go.” I knew his days were short, yet when he came into the studio I was taken aback by his frailty. I think I was hit broadside because seeing him reminded me so much of my brother, Bill, in his last days alive. On the one hand each was still fighting cancer and yet there before you was a map illustrating how a disease overwhelms a body.

Paul spent his last months writing a book called When Breath Becomes Air. It’s a searing memoir that at times strikes you so hard, you cry. Already, it’s being heralded as a great book that is “indelible.”

One passage still stabs at my heart. It’s the rawest part of the article he wrote for Stanford Medicine, and it’s included in the book. It’s written as a note to his daughter, Cady, conceived after he was diagnosed and born while sand was slipping through his fingers:

When you come to one of the many moments in life when you must give an account of yourself, provide a ledger of what you have been and done, and meant to the world, do not, I pray, discount that you filled a dying man’s days with sated joy. A joy unknown to me in all my prior years, a joy that does not hunger for more and more, but rests, satisfied. In this time, right now, that is an enormous thing.

Now that his book has been published, it’s his widow, Lucy, a physician at Stanford, who has become his voice. As we sat down for this 1:2:1 interview I told her I had felt so unsure about the direction of my questions the day I spoke to her husband. How do you sit across from someone living and talk about their dying? The same anxiety was there before I spoke with Lucy. Were there areas of grief still bandaged over that I shouldn’t try to uncover?

In the end, the conversation with Lucy feels like a bookend. What began with Paul, a discussion about the time that remained for him, is cemented now with her words after he’s gone. (As we began, I told her that months before when Paul and I had talked he had sat in the same chair she was in. It comforted her knowing that.)

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Education, Stanford Medicine Unplugged, Surgery

Ten percent more: Skirting the line between life and death in surgery

Ten percent more: Skirting the line between life and death in surgery

Stanford Medicine Unplugged (formerly SMS Unplugged) is a forum for students to chronicle their experiences in medical school. The student-penned entries appear on Scope once a week during the academic year; the entire blog series can be found in the Stanford Medicine Unplugged category

surgeryI was in the middle of my surgery rotation and was scrubbed in on a gastrectomy. A gastrectomy is a procedure to remove a patient’s stomach; in this case because of a stomach cancer. It’s a major operation that requires the manipulation of delicate structures but it offers an excellent outcome for many patients.

My job during the gastrectomy was to be a retractor – a classic medical student role. Retraction is a simple mechanical job that involves pushing skin, muscle, and other tissue out of the way in order to help the surgeons visualize the field in which they are working. More specifically, the attending surgeon handed me a metal plate and told me to use it to push down hard on the intestines so that we could get a good view of the stomach and associated blood vessels in the area. I was positioned behind the resident, who would be the one taking advantage of that view.

I pushed down with my left hand as the attending and resident went about clipping vessels and clearing tissue. Suddenly, the field of view filled up with blood. Some bleeding is to be expected during any surgery, particularly one like this. But this was more than expected.

The attending immediately started calling out orders. He told the resident to find the source of bleeding so that we could ligate it or clip it off. He asked the anesthesiologist to get blood ready in case we needed a transfusion. And then he turned to me and said, “Akhilesh, I need you to push down 10 percent harder. If we lose the field of view here, we might not find it again.”

I pushed down harder, and the search for the source of bleeding continued. The attending told us not to panic (when the attending says “Don’t panic,” that’s how you know there’s a reason to panic). He turned his attention back to me.

“Akhi, I need 10 percent more pressure.” And then: “20 percent more.”

I was getting tired.

“I know you’re getting tired bro, but give me 10 percent more.”

Finally, after a great deal of suctioning, searching, and approximately 130 percent more pressure, we found the source and stopped the bleeding. Everyone paused for a second to breathe a sigh of relief, and then it was back to the procedure.

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Education, Events, Stanford News

Hangout with Stanford’s Internal Medicine Residency program on Jan. 28

Hangout with Stanford’s Internal Medicine Residency program on Jan. 28

Have you ever wondered what it’s like to be an internal medicine resident at Stanford? Now’s your chance to learn more.

This Thursday, Stanford’s Internal Medicine Residency program will host a Google+ Hangout. Tune in at 1 PM Pacific to hear from program leadership and current residents as they share their experiences and answer questions about life at Stanford. Ron Witteles, MD,  program director and an associate professor of medicine, will moderate the one-hour discussion, which will touch on a variety of topics, including mentorship programs and research opportunities.

You can join the conversation here.

In the News, Pediatrics, Stanford News, Videos

“The need is out there”: A look at the new Teen Van

"The need is out there": A look at the new Teen Van

It’s big, blue and beneficial to hundreds of San Francisco Bay Area teens who don’t have the means or the motivation to visit a traditional doctors’ office.

The Mobile Adolescent Health Services Program operated by Lucile Packard Children’s Hospital Stanford — aka the Teen Van — was featured on this recent Bay Area Proud segment from NBC Bay Area.

Spearheaded by Seth Ammerman, MD, clinical professor of pediatrics, the van provides a host of health services to teens — 40 percent of whom are currently homeless or have been in the past year, Ammerman says.

Although the program has been around since 1996, the van itself is new, offering more space and enhanced technology. And there’s plenty of work to be done.

“The need is out there, unfortunately, for more programs like this,” Ammerman says.

Previously: Adolescent Health Van wins community award for aiming to “help kids turn their lives around” and Packard Children’s Adolescent Health Van celebrates 15 years
Video courtesy of NBC Bay Area

In the News, Public Health, Sleep

How to tell if you’re sleep deprived

How to tell if you're sleep deprived

mad cartoonAre you chronically cranky or hungry (or, worse, hangry)? Are you clumsy or prone to nodding off during a show? Those are just a few of the signs that you may be sleep-deprived — signs that are hilariously depicted through a series of TV and movie clips in a fun new Bustle piece. The article caught my attention because it includes comments from Stanford sleep expert Rafael Pelayo, MD, (who explains why being short on z’s can make it difficult to fall asleep at one’s normal bedtime), but I also quite like the wise words of writer Chrissa Hardy:

Functioning isn’t thriving, just as surviving isn’t really living. The bare minimum is never the goal, and sleeping the shortest amount of time in order to get through the following day is no way to present your best self to the world.

In other words, go get some sleep.

Previously: Stanford doc gives teens a crash course on the dangers of sleep deprivationStanford docs discuss all things sleepExploring the effect of sleep loss on health and What are the consequences of sleep deprivation?
Photo by Ben Piddington

Cancer, Patient Care, Stem Cells, Transplants

The inside scoop on bone marrow transplants

The inside scoop on bone marrow transplants

blood-156063_1280Your bones harbor blood manufacturing factories. Those factories, packed in the bone marrow, produce stem cells that develop into red blood cells, white blood cells and platelets. Cancers such as leukemia and a few genetic conditions can weaken the bone marrow, necessitating a bone marrow transplant.

Witold Rybka, MD, director of the Bone Marrow Transplantation Program at Penn State Hershey, fielded questions recently in this Q&A on the procedure. An excerpt:

What are the most common types of bone marrow transplants?

For an autologous transplant, the patient can bank his or her own stem cells before undergoing intensive treatment for certain diseases such as lymphoma, Hodgkin’s lymphoma or multiple myeloma. The patient’s body can then use its own banked stem cells to regenerate healthy marrow once treatment is complete. Other transplants are allogeneic, meaning that the patient must receive matching stem cells from a sibling, family member or unrelated donor.

What are the odds of finding a match within one’s own family?

The chance of finding a full match is one in four, so the larger your family, the better chance you have of finding a match among your relatives. Given the size of most American families, most donors must use an unrelated match from a registry of more than 17 million living donors worldwide.

Unfortunately, it’s possible that a patient who needs a bone marrow transfusion won’t get one. Most banked stem cells are from donors in North America and Europe, making it easier for white patients to find a match. For patients of other ethnicities, the chance of finding a donor is only 60 percent, Rybka said.

To learn more about bone marrow transplants, visit Be The Match.

Previously: Bone marrow transplantation: The ultimate exercise in matchmaking, Bone marrow transplantation field mourns passing of pioneer Karl Blume and One (blood stem) cell to rule them all? Perhaps not, say Stanford researchers
Image by OpenClipartVectors

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