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Neuroscience, Parenting, Research, Stanford News

Math and the brain: Memorization is overrated, says education expert

Math and the brain: Memorization is overrated, says education expert

4008476814_a7d70651f7_zRemember being drilled multiplication tables? Or taking a timed math exam? These have been common activities in school, but Stanford experts say they’re not really helpful to kids learning math facts. In fact, they deter students who might otherwise be excellent mathematicians.

Jo Boaler, PhD, is a professor of mathematics education and lead author on a new working paper, “Fluency without Fear.” As part of the research, educators looked at MRI scans of students who are better and worse at math memorization. The only difference in the brain shows up in the hippocampus, the working memory center, leading researchers to believe that there are no differences in math ability, analytical thought, or IQ between the groups. Moreover, the working memory shuts down when under stress. This makes it harder to recall facts when under time pressure, and seems to particularly affect high-achieving and female students.

Boaler’s research shows that students are better at math when they’ve developed “number sense,” or the ability to use numbers flexibly and understand their logic, which comes from relaxed, enjoyable, and exploratory work. Investigators found that high-achievers actually use number sense, and not rote memorization; likewise, it’s not that low-achieving students know less, but that they don’t use numbers flexibly.

Boaler told Stanford News, “They have been set on the wrong path, often from an early age, of trying to memorize methods instead of interacting with numbers flexibly… Number sense is the foundation for all higher-level mathematics.”

So, good math students are not necessarily fast math students, which is a common misconception. In fact, many mathematicians are slow with numbers, because they think carefully about them. The danger is that kids who aren’t fast with math sometimes become convinced they’re not good at it, and they turn away.

Compare times-tables drilling with how English is commonly taught. Students learn words by using them in many different settings: reading novels or poetry, writing thoughtful pieces, speaking about their thoughts or observations. “No English student would say or think that learning about English is about the fast memorization and fast recall of words,” says Boaler.

Boaler teaches a class for educators, “How to learn math,” in which she encourages a variety of math activities, including those that focus on the visual representation of number facts. Visual and symbolic number associations use different pathways in the brain, and connecting them deepens learning, as shown by recent brain research.

Photo by Jimmie

Neuroscience, Research, Stanford News

Face blindness stems from differences in neurocircuitry

Face blindness stems from differences in neurocircuitry

14769-faces_newsA recent Stanford News article stopped me in the first paragraph with its line, “One in 50 people can’t recognize faces.” That’s a huge number of people, including, somewhat disappointingly, Brad Pitt, whose face I would certainly recognize anywhere… These folks see eyes, a nose and a mouth — but they don’t put it together into a coherent whole.

Now, Stanford researchers have discovered that’s because their neurocircuitry is a bit different.

From the article:

The brain’s regions for face recognition and space recognition each perform similar functions, and they are located near each other.

For people with normal face and space recognition, the brain’s wiring for each region appears the same.

But in adults with face blindness, the wiring of the face-recognition region is different from the wiring of space-recognition center. Using that difference alone, researchers successfully predicted the presence of face blindness in adults who had previously been tested for the condition using only behavioral measures.

Stanford neuroscience graduate student Jesse Gomez helped solve the mystery by mastering a software model that shows how naturally occurring water in the brain moves through white matter. Axons, or the networking extensions of neurons, are sheathed in a substance called myelin, which is white. He found that a specific pattern of water movement predicts face blindness.

Next, he hopes to examine 5- to 11-year-old children to see how white matter changes during development, to figure out if a certain white-matter network will predict future face recognition ability.

Previously: In a human brain, knowing a face and naming it are separate worries, Metamorphosis: At the push of a button, a familiar face becomes a strange one and Image of the week: Oligodendrocyte
Photo by L.A. Cicero

Genetics, Neuroscience, Stanford News

“The uncertainty was killing me”: A student’s tale of genetic testing for Huntington’s disease

"The uncertainty was killing me": A student's tale of genetic testing for Huntington’s disease

happyImagine you had a 50 percent chance of being diagnosed with a disease that progressively breaks down the nerve cells of your brain, and that as early as your 30s or 40s you could begin exhibiting a range of symptoms of including involuntary movements, emotional problems and cognitive impairment. Such was the fate of Stanford student Kristen Powers.

Powers was three years old when her mother began experiencing symptoms of an incurable neurodegenerative disorder called Huntington’s disease, which claimed her mother’s life in 2011 at the age of 45. By the time she was 11, Powers became fully aware that she and her brother, Nate, had a 50/50 chance of someday developing the disease. Not long after, she learned that a genetic test could tell her if she carried the gene mutation that causes Huntington’s. The only problem was, she had to be 18 in order to take the test.

“The uncertainty was killing me,” said Powers, who was recently named one of the “15 incredibly impressive students at Stanford” by Business Insider. “I was constantly thinking about this ‘What if?’ scenario and it was very consuming in terms of my thoughts and conversations with my best friend. It was getting very tiresome.”

But rather than letting frustration and anxiety dominate her life, Powers channeled her energy into producing a documentary film, titled Twitch, about her experience growing up with her mother’s illness and the potential of carrying the Huntington’s gene.

“My film helped prepare me a lot because it gave me a sense of control in a process that was, very much, out of my control,” she said. “I could distract myself constructively and positively. My film was also a very important process for preparing for the results.”

Distraction came in the form of learning the documentary film business before she was barely old enough to drive a car. Powers had to pitch the idea of potential investors, raise money, hire a film crew, learn about film rights and copyright laws, work with attorneys to draft contracts, and make sure the production didn’t go broke.

To fund the film, she launched a crowdfunding campaign on Indiegogo. “I had decided that if the fundraising campaign was a failure I would take it as sign that I shouldn’t make the film,” she said.

But in the end she raised $18,025, 80 percent more than the goal amount. “I was so surprised. I had never raised more than $300. Within the first night we hit $1,000 and we hit our goal amount on the one-year anniversary of my mom’s passing,” said Powers.

On May 18, 2012, the long-awaited day finally arrived. Accompanied by her family and best friend, Powers took the test that, in her mind, would dictate major life decisions such as if she would have children. When the test results came back two weeks later, she learned the good news: She tested negative.

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Behavioral Science, Complementary Medicine, Neuroscience, Videos

This is your brain on meditation

This is your brain on meditation

For years, friends have been telling me I should try meditation. I’m embarrassed to admit it’s mostly because of (how can I put this delicately?) a temper that flares when I’m anxious or stressed out. But, as it is for many people, it’s one of those things I haven’t gotten around to. This video by AsapSCIENCE, though, describing the things scientists have discovered about meditators has me thinking about it again.

Meditation is linked to a decreased anxiety and depression, and increased pain tolerance. Your brain tunes out the outer world during meditation, and on brain scans of meditators, scientists can see increased activity in default mode network – which is associated with better memory, goal setting, and self-awareness. The part of the brain that controls empathy has also been shown to be more pronounced in monks who are long-time meditators. From the video:

“[Meditation] also literally changes your brain waves, and we can measure these frequencies. Medidators have higher levels of alpha waves, which have been shown to reduce feelings of negative mood, tension, sadness and anger.”

Much like hitting the gym can grow your muscles and increase your overall health, it seems that meditation may be a way of working out your brain—with extra health benefits.”

Other demonstrated benefits include better heart rate variability and immune system function. I’m glossing over a lot of the information that’s packed into this entertaining little video, but if you’re curious, check out this less-than-three-minute video yourself.

Previously: Study shows benefits of breathing meditation among veterans with PTSDResearch brings meditation’s health benefits into focusUsing meditation to train the brainCan exercise and meditation prevent cold and flu? and How meditation can influence gene activity
Video by AsapSCIENCE

Mental Health, Neuroscience, Stanford News, Videos

Hope for the globby thing inside our skulls

Hope for the globby thing inside our skulls

While at the World Economic Forum annual meeting in Davos, neuroscientists Tony Wyss-Coray, PhD, and Amit Etkin, MD, PhD, had a webcast conversation with NPR correspondent Joe Palca as part of his series of conversations on brain science. During their conversation, Palca asked about the current state of treatment for mental health and neurodegenerative diseases (bad) and prospects for the future (better).

When asked the single most important thing people could do for their mental health, Etkin answered, “awareness”. He said people need to be aware of their mental health and know that help exists if they seek it out. Current treatments aren’t perfect, but they are better than no treatment at all.

They also discussed molecular tools for diagnosing degenerative diseases, and the goals of the Stanford Neurosciences Institute‘s Big Ideas in Neuroscience teams that the two co-lead to develop new diagnostics and treatments for mental health (Etkin) and neurodegenerative diseases (Wyss-Coray).

At the end, Palca summarized the wide-ranging conversation saying, “I think it’s a time of actually some hope. I feel quite positive that this globby thing that sits inside our skulls is being understood in enough detail to make some precise changes that can be helpful.”

Previously: Neurosciences get the limelight at DavosNeuroscientists dream big, come up with ideas for prosthetics, mental health, stroke and more

Mental Health, Neuroscience, Stroke

Neurosciences get the limelight at Davos

Neurosciences get the limelight at Davos

IMG_0887Four faculty from the Stanford Neurosciences Institute have been in Davos for the past few days attending the World Economic Forum along with world leaders and economic illuminati. They were invited to form a panel about the recently announced Big Ideas in Neuroscience, which is a novel way of bringing faculty together around health challenges like stroke, neurodegenerative disease and mental health conditions. If this approach is successful it could help ease the crippling economic and emotional costs of those diseases.

Amit Etkin, MD, PhD, emailed me from the conference that attendees seem to be very excited and focused on the sessions, with lines out the door of people waiting for seating. The entire panel included Etkin, who co-leads a mental health team, Marion Buckwalter, MD, PhD, who leads a stroke collaboration, and Tony Wyss-Coray, PhD, and Anne Brunet, PhD, who are both part of the neurodegenerative disease team.

Tomorrow at 6 a.m. Pacific Time both Etkin and Wyss-Coray will be webcast live in conversation with NPR correspondent Joe Palca. That webcast is available on the World Economic Forum website.

Previously: Neuroscientists dream big, come up with ideas for prosthetics, mental health, stroke and more, Stanford expert responds to questions about brain repair and the future of neuroscience

Imaging, Neuroscience, Research, Science, Stanford News

New insights into how the brain stays bright

New insights into how the brain stays bright

Neon brainAxel Brunger, PhD, professor and chair of Stanford’s Department of Molecular and Cellular Physioogy , and a team composed of several Stanford colleagues and UCSF scientists including Yifan Cheng, PhD, have moved neuroscience a step forward with a close-up inspection of a brain-wide nano-recycling operation.

A healthy adult brain accounts for about 2 percent of a healthy person’s weight, and it consumes about 20 percent of all the energy that person’s body uses. That’s a lot of sugar getting burned up in your head, and here’s why: Incessant chit-chat throughout the brain’s staggeringly complex circuitry. A single nerve cell (of the brain’s estimated 100 billion) may communicate directly with as many as a million others, with the median in the vicinity of 10,000.

To transmit signals to one another, nerve cells release specialized chemicals called neurotransmitters into small gaps called synapses that separate one nerve cell in a circuit from the next. The firing patterns of our synapses underwrite our consciousness, emotions and behavior. The simple act of tasting a doughnut requires millions of simultaneous and precise synaptic firing events throughout the brain and, in turn, precisely coordinated timing of neurotransmitter release.

You’d better believe these chemicals don’t just ooze out of nerve cells at random. Prior to their release, they’re sequestered within membrane-bound packets, or vesicles, inside the cells. Every time a nerve cell transmits a signal to the next one – which can be more than 100 times a second – hundreds of tiny chemical-packed vesicles approach the edge of the first nerve cell and fuse with its outer membrane, like a small bubble merging with a larger one surrounding it. At just the right time, numerous vesicles’ stored contents spill out into the synapse, to be quickly taken up by receptors dotting the nearby edge of the nerve cell on the synapse’s far side, where, like little electronic ones and zeroes in a computer circuit, they may either trigger or impede the firing of an impulse along that next nerve cell.

Each instance of bubble-like fusion – and this happens not only in neurotransmitter release but in hormone secretion and other processes throughout the body – is carefully managed by a complex of interconnecting proteins, collectively known as the SNARE complex. The molecular equivalent of a clamp, the SNARE complex guides the vesicle ever nearer to the nerve-cell’s surface and then, at just the right moment, squishes it up against the cell’s outer membrane. The vesicle bursts, spilling its contents into the synapse.

Myriad repetitions of this process typify the average day in the life of the average nerve cell. This requires not only a ton of energy (which I guess is where the doughnut comes in) but ultra-efficient recycling. The entire SNARE complex must be constantly disassembled, then reassembled. In a new study in Nature, Brunger and his associates snagged a set of near-atomic-scale snapshots of the SNARE complex as well as the molecular machinery that recycles its components, allowing them to make sophisticated guesses about how the whole thing works. (See the Howard Hughes Medical Institute’s news release on the study here.)

This has been a long time coming. In fact, Brunger’s lab first determined the molecular structure of the SNARE complex, via X-ray crystallography, in 1998. The careful decades-long process of tracking down the SNARE complex’s components and their interactions won Stanford neuroscientist Tom Sudhof, MD, the 2013 Nobel Prize in Medicine. But despite its immense importance, you probably haven’t heard much about it. Studies of molecular structures are in general opaque to lay readers, complicated systems such as the SNARE complex all the more so. The popular press pays attention to the awarding of the Nobel, but seldom to the long, towering staircase of incremental discoveries that was climbed to earn it.

Previously: Revealed: The likely role of Parkinson’s protein in the healthy brain, Step by step, Sudhof stalked the devil in the details, snagged a Nobel and But is it news? How the Nobel prize transformed “noteworthy” into “newsworthy”
Photo by Carolyn Speranza

Neuroscience, Research, Sports, Stanford News

Forces at work in concussions more complicated than previously thought, new Stanford study reveals

Forces at work in concussions more complicated than previously thought, new Stanford study reveals

640px-Hischool_football_sunsetThe college bowls of New Year’s Day are behind us, and many football fans are already looking forward to next month’s Super Bowl. But they’re also talking more about the traumatic head injuries that plague football players, which scientists and clinicians still don’t understand fully.

One Stanford team is measuring the physical forces that an athlete’s head undergoes in a much more detailed way than in past studies, using a specially-outfitted mouthguard that we wrote about last year. Just before Christmas, Stanford bioengineer David Camarillo, PhD, and his team published a paper in the Annals of Biomedical Engineering that provides a much more complete picture of head injuries among athletes.

Helmets used in football and other sports are only evaluated on how well they protect in three directions of movement: front/back, up/down, and left/right. But, as a press release from the university notes, researchers suspect that rotational accelerations (roll, pitch, yaw) play an important role in serious injuries.

The team customized a commercially available mouthguard to measure movement in all six directions, and they recorded 500 impacts on Stanford football players, local boxers and mixed martial arts athletes. Two of the impacts resulted in concussions. The researchers analyzed the impacts and found that using six degree-of-freedom data proved to be more predictive of injuries than the current three degree-of-freedom standard. They also found that one particular part of the brain is more likely involved in concussion injuries. The release details these findings:

The current work… has helped identify a brain structure that bears closer scrutiny for its potential role in concussion symptoms. While the two concussion impacts inflicted very different magnitude and directional forces on the head, computer models indicated that they both put strain on a particular part of the brain, the corpus callosum. Previous concussion studies have identified the corpus callosum as a potential injury site.

“One of the things the corpus callosum does is manage depth perception and visual judgment by communicating and integrating information from each eye across the left and right hemisphere of the brain,” said lead author Fidel Hernandez, a mechanical engineering graduate student in Camarillo’s lab. “If your eyes can’t communicate, your ability to perceive objects in three dimensions may be impaired and you may feel out of balance, which is a classic concussion symptom.”

At the beginning of this year, a new law went into effect in California limiting the time high school football players’ full-contact practice time to just two 90 minute sessions per week; the new law also bans out-of-season full-contact practice. Texas has had a similar law on the books since 2013. The laws indicate the growing concern over head injuries, and more accurate information from studies like Camarillo’s can help coaches and parents decide when a player needs to step off the field.

Beyond influencing possible changes to industry standards, another possible implications for Camarillo’s research is that it will allow coaches to remotely monitor impact forces that players undergo. Many players under-report impact injuries, something that complicates understanding the phenomena. Accurate measurements can help clarify the picture.

Previously: Mouthguard technology by Stanford bioengineers could improve concussion measurementStanford undergrad studies cellular effects of concussionsKids and concussions: What to keep in mindDeveloping a computer model to better diagnose brain damage, concussions and Study suggests football-related concussions caused by series of hits, not a single blow.
Photo by  Jacoplane

Neuroscience, Stanford News, Videos

A detailed look at latest advancements in treating brain tumors

A detailed look at latest advancements in treating brain tumors

Advancements in radiology and imaging combined with the increasing use of robotics and computers in neurosurgery have dramatically changed the way physicians treat brain tumors. Steven Chang, MD, director of the Stanford Neurogenetics Program and the Stanford Neuromolecular Innovation Program, offers an overview of these revolutionizing techniques in this Stanford Health Care video.

During the lecture, Change provides specific examples of how cutting-edge technologies and therapies have improved patient outcomes. One such technology is intraoperative MRI (iMRI), which allows surgeons to image the patient while on the operating room table to achieve a more complete removal of the brain tumor. He also addresses how radiosurgery can overcome challenges in treating tumors near the optic nerve, which pose a threat to individuals’ vision, or in other high-risk cases, such as patients likely to experience cardiac complications during or after surgery. Watch the full talk to learn more about what the future of neurosurgery holds.

Previously: A Stanford neurosurgeon discusses advances in treating brain tumors, Stanford celebrates 20th anniversary of the CyberKnife and Stanford brain tumor research featured on “Bay Area Proud”

Genetics, Neuroscience, Research, Science, Stanford News

Yeast advance understanding of Parkinson’s disease, says Stanford study

Yeast advance understanding of Parkinson's disease, says Stanford study

It’s amazing to me that the tiny, one-celled yeast can be such a powerful research tool. Now geneticist Aaron Gitler, PhD, has shown that the diminutive organism can even help advance the understanding of Parkinson’s disease and aid in identifying new genes involved in the disorder and new pathways and potential drug targets. He published his findings today in Neuron and told me in an email:

Parkinson’s disease is associated with many genetic and environmental susceptibility factors. Two of the newest Parkinson’s disease genes, EIF4G1 and VPS35, encode proteins involved in protein translation (the act of making protein from RNA messages) and protein sorting (shuttling proteins to the correct locations inside the cell), respectively. We used unbiased yeast genetic screens to unexpectedly discover a strong genetic interaction between these two genes, suggesting that the proteins they encode work together.

The proteins, EIF4G1 and VPS35, have changed very little from yeast to humans. Gitler and his colleagues showed that VPS35 interacts functionally with another protein implicated in Parkinson’s disease, alpha-synuclein, in yeast, round worms and even laboratory mice. As Gitler described:

Together, our findings connect three seemingly distinct Parkinson’s disease genes and provide a path forward for understanding how these genes might contribute to the disease and for identifying therapeutic interventions. More generally, our approach underscores the power of simple model systems for interrogating even complex human diseases.

Previously: Researchers pinpoint genetic suspects in ALS and In Stanford/Gladstone study, yeast genetics further ALS research

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