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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.

Global Health, Infectious Disease, Public Health, Public Safety, Stanford News

Biosecurity experts discuss Ebola and related public health concerns and policy implications

Biosecurity experts discuss Ebola and related public health concerns and policy implications

ebola_081214

More than 1,800 people in the West African nations of Liberia, Sierra Leone and Guinea have contracted the Ebola virus since March and the death toll has surpassed 1,000, according to the latest figures from the World Health Organization. As the number of cases and death continue to climb many are concerned about what can be done to curtail the outbreak and the likelihood of it spreading to the United States.

In a Q&A recently published by the Center for International Security and Cooperation and The Freeman Spogli Institute for International Studies, Stanford biosecurity experts David Relman, MD, and Megan Palmer jointly answer these questions and others related to the public health concerns and policy implications of the outbreak. On the topic of broader lessons about the dynamics and ecology of emerging infectious diseases that can help prevent or respond to outbreaks now and in the future, they respond:

These latest outbreaks remind us that potential pathogens are circulating, replicating and evolving in the environment all the time, and human action can have an immense impact on the emergence and spread of infectious disease.

We are starting to see common factors that may be contributing to the frequency and severity of outbreaks. Increasing human intrusion into zoonotic disease reservoir habitats and natural ecosystems, increasing imbalance and instability at the human-animal-vector interface, and more human population displacement all are likely to increase the chance of outbreaks like Ebola.

The epicenter of this latest outbreak was Guéckédou, a village near the Guinean Forest Region. The forest there has been routinely exploited, logged, and neglected over the years, leading to an abysmal ecological status quo. This, in combination with the influx of refugees from conflicts in Guinea, Liberia, Sierra Leone, and Cote d’Ivoire, has compounded the ecological issues in the area, potentially facilitating the spread of Ebola. There seems to be a strong relationship between ecological health and the spread of disease, and this latest outbreak is no exception.

While forensic analyses are ongoing, unregulated food and animal trade in general is also a key factor in the spread of infectious diseases across large geographic regions. Some studies suggest that trade of primates, including great apes, and other animals such as bats, may be responsible for transit of this Ebola strain from Central to Western Africa.

Overall, Relman and Palmer remind the public, “It’s important that we not lose sight of more chronic, but less headline-grabbing diseases that will be pervasive, insidious long-standing challenges for Africa and elsewhere.”

Previously: Stanford global health chief launches campaign to help contain Ebola outbreak in Liberia and Health workers use crowdsourced maps to respond to Ebola outbreak in Guinea
Photo by European Commission DG ECHO

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.

Medical Apps, Stanford News, Technology

A Stanford physician shares his experiences creating evidence-based medical apps

iPad_080814A piece published earlier this week on iMedicalApps spotlights the work of Steven Lin, MD, a clinical instructor in family medicine at Stanford who is the co-creator of two evidence-based medical apps. The first app he helped develop was Ilithyia, a point-of-care clinic prenatal app, and the second is L’Allegro, which helps physicians select the appropriate antidepressant for patients. From the piece:

Dr. Lin first thought about creating an app as an intern when he noted the large gap between what he had learned in medical school and what was happening in practice. He had knowledge but it was often difficult translating that knowledge into point of care practice. He first concentrated on prenatal visits as he wanted to find the evidence base for current practice and make that available to himself as well as his fellow interns.

He started with researching guidelines, community standard of care, and even insurance allowances for visits and labs. He then took this information and made a framework of sorts. Each visit had allotted information- labs, guidance, findings, etc, and this framework became the basis for how he organized his app.

Lin and partner, a programmer who was finishing his final year of high school when they started working together, plan to “work with the Society for Teachers in Family Medicine and plans to create a mobile version of their study cases” for third app.

Previously: Heart bypass or angioplasty? There’s an app for that, A conversation about smart-device use among resident physicians and Stanford AIM Lab launches patient exam iPad app
Photo by Stanford EdTech

Patient Care, Pediatrics, Stanford News, Videos

Pediatric patients create vibrant mural with help from Hewlett-Packard and DreamWorks Animation

Pediatric patients create vibrant mural with help from Hewlett-Packard and DreamWorks Animation

Here’s a feel-good story that will lift your spirits. Over at Lucile Packard Children’s Hospital Stanford, patients are working with volunteers from Hewlett-Packard and DreamWorks Animation to construct a unique piece of artwork designed digitally or drawn by hand. As described in the above video, the DreamWorks team worked with children in the hospital’s onsite school to create imaginary creatures, and next built a background and composited the patients’ art into a large mural. Then, Hewlett-Packard printed the custom designs onto PVC-free wallpaper. The final mural now hangs in Hewlett-Packard’s Palo Alto headquarters.

Previously: Ensuring young dialysis patients make the grade

Neuroscience, Research, Stanford News

Non-invasive technique uses lasers and carbon nanotubes to provide view of blood flow in the brain

Non-invasive technique uses lasers and carbon nanotubes to provide view of blood flow in the brain

When researchers want to explore the brain of living animals, they have two options: surgically remove part of the skull, a procedure that can alter its function or trigger an immune response, or use CT or MRI scans, which isn’t effective for visualizing activity of individual vessels or groups of neurons. But a new approach developed by Stanford chemists holds the promise of offering a third option that is non-invasive and captures “an unprecedented look at blood flowing through a living brain.”

The technique involves injecting water-soluble carbon nanotubes into the subject’s bloodstream, in this case mice, and using near-infrared light to illuminate the brain vasculature and track cerebral blood flow. The work, which was published in Nature Photonics, could be useful in advancing the study of stroke and migraines, as well as Alzheimer’s and Parkinson’s diseases. According to a recent Stanford Report story:

Amazingly, the technique allows scientists to view about three millimeters underneath the scalp and is fine enough to visualize blood coursing through single capillaries only a few microns across, said senior author Hongjie Dai, a professor of chemistry at Stanford. Furthermore, it does not appear to have any adverse affect on innate brain functions.

….

The technique could eventually be used in human clinical trials, Hong said, but will need to be tweaked. First, the light penetration depth needs to be increased to pass deep into the human brain. Second, injecting carbon nanotubes needs approval for clinical application; the scientists are currently investigating alternative fluorescent agents.

Previously: Lightning strikes twice: Optogenetics pioneer Karl Deisseroth’s newest technique renders tissues transparent, yet structurally intact, Peering into the brains of freestyle rappers to better understand creativity and Brain imaging, and the “image management” cells that make it possible

Behavioral Science, Mental Health, Research

Pump up the bass, not the volume, to feel more powerful

Pump up the bass, not the volume, to feel more powerful

runner_iPodAs any seasoned athlete or fitness fanatic knows, a meticulously curated playlist is key when staying focused before a big game or getting through a tough workout. But what is it about music that transforms our psychological state and make us feel more powerful?

To answer this question, researchers at the Kellogg School of Management at Northwestern University identified so-called “highest power” songs (such as Queen’s “We Will Rock You“) and “lowest power” tunes (such as Fatboy Slim’s “Because We Can“) and then performed a series of experiments designed to ascertain how the music affected individuals’ sense of power, perceived sense of control, competitiveness and abstract thinking. According to a release, their findings showed “that the high-power music not only evoked a sense of power unconsciously, but also systematically generated the three downstream consequences of power.”

Since participants didn’t report increased feelings of empowerment after reading the lyrics of the songs, researchers turned their attention to how manipulation of bass levels impacted listeners. More from the release:

In the bass experiments, the researchers asked participants to listen to novel instrumental music pieces in which bass levels were digitally varied. In one experiment, they surveyed participants about their self-reported feelings of power, and in another, they asked them to perform a word-completion task designed to test implicit, or unconscious, feelings of power. They found that those who listened to the heavy-bass music reported more feelings of power and generated more power-related words in the implicit task than those listening to the low-bass music.

The effects of the bass levels support one possible explanation for why music makes people feel more powerful: the “contagion hypothesis.” The idea is that when people hear specific music components that express a sense of power, they mimic these feelings internally. “Importantly, because we used novel, never-before-heard music pieces in these experiments, it suggests that the effect may sometimes arise purely out of contagion,” [Dennis Hsu, PhD,] says. “Of course, this does not preclude the possibility that music could induce a sense of power through other processes, such as conditioning.”

The “conditioning hypothesis” suggests that certain pieces of music might trigger powerful experiences because these experiences are often paired with that particular music. For example, music used frequently at sports events may elicit powerful feelings because of the association with power, rewards, and winning (e.g., “We Are the Champions” is often played to celebrate victory).

Previously: Why listening to music boosts fitness performance, Can music benefit cancer patients? and Prescription playlists for treating pain and depression?
Photo by Bert Heird

In the News, Pediatrics, Stanford News, Surgery, Transplants

Parents’ heroic effort help 12-year-old daughter receive a new heart and lungs

Parents' heroic effort help 12-year-old daughter receive a new heart and lungs

Fewer than 10 children received a heart-lung transplant in the United States last year. One of them was 12-year-old Katie Grace Groebner, who was diagnosed with pulmonary hypertension in 2008 and given a year to live.

Determined to save their daughter’s life, Katie Gracie’s parents sold their house in Minnesota and most of their belongings and moved to the Bay Area so she could be treated by Jeffrey Feinstein, MD, director of the Center for Pulmonary Vascular Disease at Lucile Packard Children’s Hospital Stanford.

As reported in the NBC Bay Area segment above, the Groebners understandably call Katie’s doctors and nurses “heroes,” but Feinstein says it’s the other way around. “You want to find a hero? Talk about the parents,” he says in the video. “If you look at the amount of work that I did, compared to amount of work Katie Grace’s parents did? There’s no comparison.”

Previously: Living long term with transplanted organs: One patient’s story, Stanford study in transplant patients could lead to better treatment, Anatomy of a pediatric heart transplant and ‘Genome transplant’ concept helps Stanford scientists predict organ rejection

In the News, Medical Education, Medical Schools, Stanford News

Rethinking the traditional four-year medical curriculum

Rethinking the traditional four-year medical curriculum

In an effort to meet the needs of medical students, physicians and patients, a number of universities are considering ways to shorten the traditional four-year medical curriculum without compromising quality of care. The New York Times reports that “a recent, unpublished survey of 120 medical schools, conducted by the New York University School of Medicine, found that 30 percent were considering or already planning to start three-year programs” and notes that the American Medical Association is among those advocating for such innovative approaches. Denise Grady writes:

More than a dozen medical schools already have programs to move students more quickly from the classroom to the clinic, but by shortening premedical studies rather than medical school. Among them are Albany Medical College, Northeast Ohio Medical University and the medical schools at Boston University, Drexel, George Washington, Howard, Jefferson, Meharry and Northwestern. Gifted high school seniors or early college students are guaranteed admission to medical school if they perform well during freshman year of college. Combined bachelors/M.D. programs have been around for half a century, but these students complete both degrees in six or seven years instead of the usual eight.

“I absolutely think it’s doable,” said Dr. Charles G. Prober, senior associate dean for medical education at Stanford School of Medicine, which is considering such a program. Well-designed programs to accelerate doctors’ training “don’t send them out prematurely, but send them out with adequate tools, recognizing that they will grow,” said Dr. Prober, who writes and speaks extensively on medical education reform. “Real learning begins when you are actually beginning to take care of patients, doing what you were trained to do.”

While research is scant, a few studies show promising results. Comparisons of graduates of three-year programs at the University of Calgary and McMaster University to graduates of four-year Canadian medical schools found “equivalent performance.” And a small study at Marshall University in the 1990s, which for almost a decade incorporated fourth-year requirements with the first year of residency in family practice, declared it a success for “carefully selected candidates.”

Indeed, educators make clear that not all students can handle the accelerated curriculum. Dr. Prober notes that with the explosion of medical information, students more than ever must learn to work smart, figuring out what they need to memorize and how to find out the rest. Part of the education process today is learning to collaborate and tap the expertise of others.

Previously: A closer look at using the “flipped classroom” model at the School of Medicine, Combining online learning and the Socratic method to reinvent medical school courses, Rethinking the “sage on stage” model in medical education and Stanford professors propose re-imagining medical education with “lecture-less” classes

Medicine X, Stanford News, Technology, Videos

Medicine X symposium focuses on how patients, providers and entrepreneurs can ignite innovation

Medicine X symposium focuses on how patients, providers and entrepreneurs can ignite innovation

A special Medicine X event on Sept. 4 will explore how patients, providers and entrepreneurs can help ignite innovation in the health-care industry. During the daylong symposium, James Hereford, chief operating officer at Stanford Hospital & Clinics, will be presenting crucial opportunities for innovation in medicine today, and challenging physicians, patients and entrepreneurs to collaborate and build partnerships in an effort to create impact and change.

In the above Medicine X film, Hereford discusses the importance of patient-centered care, the need to treat the whole person and not just the illness and how including patients in pivotal discussions is crucial to transform health care. “I don’t think the world should be defined around us,” said Hereford. “I think the world should be defined around our patients.”

The brief conversation offers a taste of the thoughtful commentary that attendees can expect at this event. Other speakers include: Robert Pearl, MD, executive director and chief executive officer of The Permanente Medical Group; Stanford radiologist Lawrence Hoffman, MD; Mark Tomaino, senior industry executive at Welsh, Carson, Anderson & Stowe; Vivian Lee, MD, PhD, chief executive officer of University of Utah Health Care; and Alexandra Drane, co-founder of Eliza Corp. For more information or to register for the symposium visit the conference website.

More news about Stanford Medicine X is available in the Medicine X category.

Previously: Medicine X spotlights mental health, medical team of the future and the “no-smartphone” patient, Medicine X Live! to host Hangout on design thinking for patient engagement and Quite the reach: Stanford Medicine X set record for most number of tweets at a health-care conference

Neuroscience, Parenting, Pediatrics, Research

Can’t remember being a baby? Rapid growth of new neurons in young brains may explain why

Can't remember being a baby? Rapid growth of new neurons in young brains may explain why

baby_073014A close friend once told me that one of her favorite aspects about being a parent is that she could experience what it was like to be a baby and toddler. “As adults, we have no recollection of what it was like to be that young,” she said. “Watching my son grow up offers me a window into that part of my life.”

The inability to remember memories in early childhood is known as “infantile amnesia”. Few adults can remember events in their lifetime that occurred before the age of three. A past study shows that these memories tend to fade away around the age of seven.

But why can’t we remember our days as a crawling, toddling, babbling youngster? Recent research suggests the answer many have to do with how quickly the brain develops during this stage in our lives. According to a Scientific American article published earlier this week:

In a new experiment, the scientists manipulated the rate at which hippocampal neurons grew in young and adult mice. The hippocampus is the region in the brain that records autobiographical events. The young mice with slowed neuron growth had better long-term memory. Conversely, the older mice with increased rates of neuron formation had memory loss.

Based on these results, published in May in the journal Science, [neuroscientists Paul Frankland, PhD, and Sheena Josselyn, PhD] think that rapid neuron growth during early childhood disrupts the brain circuitry that stores old memories, making them inaccessible. Young children also have an underdeveloped prefrontal cortex, another region of the brain that encodes memories, so infantile amnesia may be a combination of these two factors.

Previously: Study finds age at which early-childhood memories fade and Individuals’ extraordinary talent to never forget could offer insights into memory
Photo by D Sharon Pruitt

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