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Neuroscience

Aging, Biomed Bites, Neuroscience, Research, Videos

Even old brains can stay healthy, says Stanford neurologist

Even old brains can stay healthy, says Stanford neurologist

This is the fourth installment of our Biomed Bites series, a weekly feature that highlights some of Stanford’s most compelling research and introduces readers to innovative scientists from a variety of disciplines. 

Aged brains aren’t quite as agile as they once were — just take it from my nearly 91-year-old grandmother, who misplaces most everything, then spends hours hunting for things, giggling all the while.

She’s fortunate. Her memory loss is minor and met with humor. But memory loss, and its accompanying symptoms, devastate millions of families annually who watch their loved ones slip away. That’s why I’m rooting for Stanford neurologist Victor Henderson, MD. Henderson and his team works to decipher the neural changes that underlie both normal aging and what he calls “dementing disorders” such as Alzheimer’s disease.

Here’s Henderson, in the video above: “Our research is focused on risk factor identification related to cognitive aging and disorders like Alzheimer’s disease and devising intervention based on the risk factors we’ve identified.”

Turns out exposure to both synthetic and natural hormones such as estrogen can affect the brain, as can exercise. And here’s the part I like best:

The findings that we’ve had and the findings we hope to make in the future have important implications for ways that people might reduce the risk of developing dementing disorders and might be able to maintain cognitive health until late old age.

Here’s hoping that Henderson hits a homer.

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

Previously: Discover the rhythms of life with a Stanford biologistStudying the drivers of metastasis to combat cancer and Studying the link between post-menopausual hormones, cognition and mood

Mental Health, Neuroscience, Technology

What email does to your brain

What email does to your brain

man yellingUpdated 10-2-14: A follow-up post, with tips on how to manage your inbox, can be found here.

***

10-1-14: Have you ever been in a situation in which you were feeling great until you received an email out of the blue that completely upset your day? How does it feel to receive 30 such emails first thing in the morning? There’s a reason why: Research shows that just looking through your inbox can significantly increase your stress levels (see research described here).

Why is this? Let’s start by defining stress. Stress is the experience of having too great a task to accomplish with too few resources to meet the demand. In the past, for our ancestors, this stress might have looked like meeting a hungry wild animal in the jungle. Today, however, it takes on a much more simple, yet equally powerful form: an inbox. Email overload is just another way in which we experience that there is too great a task (the huge list of to-dos) to handle. In the study mentioned above, email overload had a lot to do with the stress response as measured psychologically and physiologically through heart rate, blood pressure and a measure of cortisol (the “stress hormone”).

Is it just the amount of emails that lead to stress though? There’s another element that we are forgetting. The emotional impact of each email. Think about it: Usually, in our email-less past, we would experience maybe one highly emotional event a day or maybe two or three at the most, e.g. a confrontation with a colleague, perhaps a spat with a spouse, and/or a phone call from an angry neighbor. Our stress response is evolved to handle and recover from a small number of stressful situations but not a whole host of them. Unless we live in unusually extreme situations such as warzones, for example, our life usually doesn’t have frequent and sequential stressors thrown at us.

Today, however, just sitting down at our desk to check our email with a cup of coffee can bring on a deluge of emotional assailants. Between 30-300 different emotional stimuli are delivered to you within the span of minutes. From an email from your boss asking you to complete a task urgently, to a passive-aggressive message from a family-member, to news from a colleague that he’s out sick and you have to take over his workload. One hour of email can take you through a huge range of emotions and stressors. Sure, you can get happy emails too – photos of your nephews, someone’s marriage announcement – but unfortunately, research on the negativity bias shows that our brain clings more to the negative and they don’t always balance out.

That’s when our emotional intelligence is impacted. We know that when our stress response is activated, the parts of our brain that respond with fear of anxiety tend to take over, weakening our ability to make rational choices and to reason logically this study). You may be stressed; what’s more, your own ability to respond appropriately is impacted. We know that our emotions impact the way we act. You’re going to reply with a different tone if you’re upset (even at someone other than your email recipient) than if you’re not.

Have you ever pressed “send” only to regret it moments later? Don’t blame yourself. Research shows that getting depleted because you have too much on your plate reduces your self-control. For example, it can make you take more risks when maybe you should be more cautious (e.g. this study). It’s harder to have a say over our impulses when there’s just too much going on. As in too many emails, with too many different messages leading to increased stress and emotional overload.

When you’re doing a million emails – all about different topics and requesting you for different things, you are, by definition in a situation of overwhelmed multitasking. And multitasking, research shows, leads to lower productivity and makes you lose a lot of time out of our day!

So what’s the answer to the assailment of email on our lives?

Before you contemplate moving to a farm, selling your smartphone on Ebay, raising chickens and goats and cutting technology out of your life forever despite your love of selfies – WAIT, there’s a solution. Think about it – email didn’t exist 10 years ago! That means that there is a way to undo the madness. I’ll share a number of tips in my next post… Stay tuned.

Emma Seppala, PhD, is associate director of Stanford’s Center for Compassion and Altruism Research and Education and a research psychologist at the School of Medicine. She is also a certified yoga, pilates, breath work and meditation instructor. A version of this piece originally appeared on her website.

Photo by bark

Neuroscience, NIH, Research, Stanford News

Federal BRAIN Initiative funds go to create better sensors for recording the brain’s activity

Federal BRAIN Initiative funds go to create better sensors for recording the brain's activity

Optical voltage sensorUpdated 10-2-14: A quote from Schnitzer was added to the post.

***

10-1-14: Yesterday the National Institutes of Health handed out the first $46 million in funding for the BRAIN Initiative, announced in 2013. Stanford got one of those awards, worth almost $1 million to develop improved ways of recording activity in the brain.

The award went to applied physicist Mark Schnitzer, PhD, and bioengineer Michael Lin, MD, PhD, to expand on work they published last year. The pair had each developed tiny sensors that could detect voltage changes within a neuron. These provided the first real-time view of a nerve’s activity. When I wrote about their initial work earlier this year I described how these probes could be used:

With these tools scientists can study how we learn, remember, navigate or any other activity that requires networks of nerves working together. The tools can also help scientists understand what happens when those processes don’t work properly, as in Alzheimer’s or Parkinson’s diseases, or other disorders of the brain.

The proteins could also be inserted in neurons in a lab dish. Scientists developing drugs, for example, could expose human nerves in a dish to a drug and watch in real time to see if the drug changes the way the nerve fires. If those neurons in the dish represent a disease, like Parkinson’s disease, a scientist could look for drugs that cause those cells to fire more normally.

The BRAIN initiative award will help the team develop better sensors, and also improve the technology for recording the signals. In a conversation, Lin told me that a brain signal lasts about 2-4 milliseconds. Any camera for recording that activity needs to record about 1,000 frames per second, and current cameras operate at about one tenth of that speed. Schnitzer has expertise in developing tiny cameras for recording biological activity and will be working to create a faster camera to pair with Lin’s improved sensors.

Schnitzer participated in a panel discussion at a White House Brain Conference held the same day the grants were announced. He said, “I think there are many important roles for engineering and new technology that will likely emerge in the BRAIN initiative… I expect the results will be profound by helping to unlock some of the central mysteries of brain function, by providing new tools and helping to lay the basis for conceptual foundations in our efforts to prevent and cure brain disease and brain disorders and also in harnessing some of the brain’s computational strategies for humanity’s own technological purposes.”

Previously: Thoughts light up with new Stanford-designed tool for studying the brainBold and game-changing” federal report calls for $4.5 billion in brain-research fundingNIH announces focus of funding for BRAIN initiative and New tool for reading brain activity of mice could advance study of neurodegenerative diseases
Image courtesy of Michael Lin

CDC, In the News, Infectious Disease, Neuroscience, Pediatrics

Stanford experts offer more information about enterovirus-D68

Stanford experts offer more information about enterovirus-D68

Below is an updated version of an entry that was originally posted on Sept. 26.

SONY DSCLast week, the California Department of Public Health confirmed that the season’s first four cases of enterovirus-D68 respiratory illness had been found in the state, three in San Diego County and one in Ventura County, with more expected to surface. As of Sept. 29, this makes California one of 40 states across the nation to be affected by EV-D68.

Health officials in Colorado are now investigating a handful of cases of paralysis in children there; the paralysis began a few weeks after respiratory illness and appears to be connected to EV-D68. Since the same virus was tentatively linked to paralysis cases in California children earlier this year, California officials are monitoring the situation closely.

Below, Yvonne Maldonado, MD, service chief of pediatric infectious disease at Lucile Packard Children’s Hospital Stanford, answers additional questions about the respiratory symptoms caused by this virus. Keith Van Haren, MD, a pediatric neurologist who has been assisting closely with the California Department of Public Health’s investigation, also comments on neurologic symptoms that might be associated with the virus.

Enteroviruses are not unusual. Why is there so much focus from health officials on this one, EV-D68?

Maldonado: The good news is that this virus comes from a very common family of viruses that cause most fever-producing illnesses in childhood. But it’s been more severe than other enteroviruses. Some hospitals in other parts of the country have had hundreds of children coming to their emergency departments with really bad respiratory symptoms. The fact that it’s been so highly symptomatic and that there has been a large volume of cases is why it has gotten so much attention.

Van Haren: It’s important to remember that most children and adults who are exposed to enteroviruses don’t get sick at all. A smaller percentage come down with fever and/or respiratory symptoms, as Dr. Maldonado has described. And as far as we can tell, it’s only a very, very small number of children, if any, who get paralysis, typically affecting one arm or leg. The Centers for Disease Control and the California Department of Public Health are still investigating to try to determine conclusively whether EV-D68 is causing neurologic symptoms, such as paralysis.

What do we know about the course of possible neurologic symptoms of EV-D68 and their potential treatments?

Van Haren: We’re still learning about the possible neurologic symptoms and how we might treat them. To start, we have a growing suspicion that EV-D68 may be associated with paralysis. In the patients we’ve seen with paralysis, progression of weakness appears to stop on its own, and recovery of strength is very slow and usually incomplete.

Which groups are most at risk?

Maldonado: Children with a history of asthma have been reported to have especially bad respiratory symptoms with this virus. It can affect kids of all ages, from infants to teens. So far, only one case has been reported in an adult, which makes sense because adults are more likely to have immunity to enteroviruses. We do worry more about young infants than older children, just because they probably haven’t seen the virus before and can get worse respiratory symptoms with these viral infections.

Van Haren: We don’t yet know who is most at risk for paralysis or other neurologic symptoms, but we are studying this carefully to find out why some children get sick and some do not. So far, it seems that the children who have been affected by paralysis were generally healthy prior to their illness.

What is the treatment for EV-D68?

Maldonado: There is no treatment that is specific to the virus. At home, parents can manage children’s fevers with over-the-counter medications, make sure they drink lots of fluids to avoid dehydration, and help them get plenty of rest. For children who are very ill, doctors will check for secondary illnesses such as bacterial pneumonia, which would be treated with antibiotics, and may hospitalize children who need oxygen or IV hydration to help them recover.

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Events, Neuroscience, Stanford News

Open Office Hours: Stanford neurobiologist taking your questions on brain research

Open Office Hours: Stanford neurobiologist taking your questions on brain research

Newsome

Last year Stanford launched the new Stanford Neurosciences Institute, led by visionary neurobiologist William Newsome, PhD. Part of his job over the past year has been to inspire faculty to think beyond their own labs and to dream about what they could accomplish if they work together. He called this the Big Ideas in Neuroscience.

This week, Newsome will be taking questions about your Big Ideas (or Big Questions) in brain research as part of a Stanford Open Office Hours event on Facebook. Are you curious how we learn and remember? What technologies might allow us to peer into the brain and even manipulate its function? How a deeper understanding of the brain could influence public policy, education and the law? Go to the Facebook page for the event and submit your questions by tomorrow (Oct 1).

Previously: “Bold and game-changing” federal report calls for $4.5 billion in brain-research fundingDinners spark neuroscience conversation, collaborationBrain’s gain: Stanford neuroscientist discusses two major new initiatives and Co-leader of Obama’s BRAIN Initiative to direct Stanford’s interdisciplinary neuroscience institute
Photo from Stanford News Service

Aging, In the News, Neuroscience, Stanford News

Exercise and your brain: Stanford research highlighted on NIH Director’s blog

Exercise and your brain: Stanford research highlighted on NIH Director’s blog

B0007367 Thigh muscle fibrilsThomas Rando, MD, PhD, who studies stem cells in muscle and longevity, and Tony Wyss-Coray, PhD, who studies the immune system’s impact on the brain, were awarded an NIH Director’s Transformative Research Award to study the slew of molecules that muscles release and how they help muscle cells communicate with other cells. (Rando and Wyss-Coray call this cellular communication network “the communicome.”) The onset of both depression and Alzheimer’s disease have been shown to be delayed with exercise, and Rando and Wyss-Coray theorize that molecules released by muscles during exercise may be the key to understanding how exercise can affect brain function so profoundly and so beneficially.

Today on the NIH Director’s blog, Francis Collins, MD, highlighted the Stanford duo’s research:

To study the communicome, Wyss-Coray and Rando will use a technique called parabiosis to couple the circulatory systems of physically active mice with mice that are less active. If the “couch potato” mice benefit from the blood of the active mice, then the team will analyze the blood to find the responsible factor(s).

This is definitely high-risk high-reward research. It won’t be easy, but finding molecules that mimic exercise’s brain-boosting effects may open the door to new ways of preventing or treating age-related cognitive declines and a wide range of other neurological conditions. This is especially important for people for whom it is difficult or even hazardous to exercise because of conditions such as arthritis, osteoporosis, and Alzheimer’s disease and other forms of dementia.

Earlier this year, Wyss-Coray published a study showing that older mice that received transfusions of younger mice’s blood improved their brain function. That study was based in part on Rando’s previous research showing that young mouse blood could activate old stem cells and rejuvenate older tissue. Their new collaboration may shed more light on the molecular mechanisms behind such observations.

Previously: Young mouse to old mouse: “It’s all in the blood, baby”, The rechargeable brain: Blood plasma from young mice improves old mice’s memory and learning, “Alert” stem cells speed damage response, say Stanford researchers and Red light, green light: Simultaneous stop and go signals on stem cells’ genes may enable fast activation, provide “aging clock”
Photo, of thigh muscle fibrils, by David Gregory & Debbie Marshall, via Wellcome Images

Neuroscience, Research, Stanford News, Stem Cells

Cellular padding could help stem cells repair injuries

Cellular padding could help stem cells repair injuries

The idea of using stem cells to heal injuries seems so obvious. If you have a spinal cord injury, why not inject some new cells that can replace the ones that are lost?

Unfortunately, the very act of injecting those cells is rife with trouble. The scraping as they move through the needle damages the cells and can even kill them. Then, once in the site of the injury, the cells can easily ooze away into other tissue, or die from the onslaught of chemicals in the injury.

Material scientists Sarah Heilshorn, PhD, is trying to help these cells with a type of gel that can protect and support them, allowing them to live long enough to possibly repair the injury. A grant from Stanford Bio-X, the pioneering interdisciplinary life sciences institute, is now helping Heilshorn and her colleagues, neurosurgeon Giles Plant, PhD, and chemical engineer Andrew Spakowitz, PhD, get the project off the ground.

In a story I wrote about the work, Heilshorn equates the gel to ketchup:

It’s pretty thick, but when you bang on the bottle the sauce flows smoothly through the neck, then firms back up on the plate – a process she calls self-healing. “We want our polymers to self-heal better than ketchup,” she said. “It flows a bit across the plate.”

Her goal is to develop a polymer that supports the cells when they are loaded in a syringe, but then flows freely through the needle, padding and protecting the cells, then firming up quickly when it reaches the site of injury. “We don’t want the cells to flow away,” she says.

These Seed grants from Bio-X have been credited as part of what has made the institute so successful in bringing together people from diverse disciplines to solve biomedical problems. “The seed grants are the special Bio-X glue that brings teams of faculty from all over the university to tackle complex problems in human health using new approaches,” said Carla Shatz, PhD, who directs Bio-X.

We’ll be writing about a few of the most exciting projects being funded with the recently announced 2014 Bio-X Seed grants over the next few weeks.

Previously: They said “Yes”: The attitude that defines Stanford Bio-X

Neuroscience, Research, Stanford News

The life of a brain, captured by Stanford scientists

The life of a brain, captured by Stanford scientists

4_brains_fibertracts

At last, Stanford psychologists have come up with an explanation for our 20s. Or at least my 20s. That period of time when I was in so many ways an adult and yet some higher processing – inpulse control, for example – did not yet seem fully formed.

A group led by psychologist Brian Wandell, PhD, measured the brain composition of 102 people spanning ages 7 to 85 in 24 regions of the brain. The were specifically measuring what’s known as white matter – the fatty protective covering on our nerves that helps them fire more efficiently and, as the name implies, makes up the white part of our brains. People have long known that the white matter increases as the brain matures and white matter abnormalities have been associated with schizophrenia and other conditions. As I wrote in a Stanford News piece:

What [the researchers] found is that the normal curve for brain composition is rainbow-shaped. It starts and ends with roughly the same amount of white matter and peaks between ages 30 and 50. But each of the 24 regions changes a different amount. Some parts of the brain, like those that control movement, are long, flat arcs, staying relatively stable throughout life.

Others, like the areas involved in thinking and learning, are steep arches, maturing dramatically and then falling off quickly. (The group did point out that their samples started at age 7 and a lot of brain development had already occurred.)

That’s right. Thinking, learning, emotional control – none of those are firing at full capacity until around age 40. Beyond providing an excuse for a few bad decisions, the work could also become useful for doctors. In this study, the group examined the brains of people with multiple sclerosis, and they were able to detect more subtle decreases in white matter than doctors can when monitoring the disease. The researchers also say the work could help monitor effects of drugs, or diagnose kids who appear to have learning delays.

Previously: Learning how we learn to read and Teaching an old dog new tricks: New faster and more accurate MRI technique quantifies brain matter

Behavioral Science, Evolution, Imaging, Neuroscience, Research, Stanford News, Surgery

In a human brain, knowing a face and naming it are separate worries

In a human brain, knowing a face and naming it are separate worries

Alfred E. Neuman (small)Viewed from the outside, the brain’s two hemispheres look like mirror images of one another. But they’re not. For example, two bilateral brain structures called Wernicke’s area and Broca’s area are essential to language processing in the human brain – but only the ones  in the left hemisphere (at least in the great majority of right-handers’ brains; with lefties it’s a toss-up), although both sides of the brain house those structures.

Now it looks as though that right-left division of labor in our brains applies to face perception, too.

A couple of years ago I wrote and blogged about a startling study by Stanford neuroscientists Josef Parvizi, MD, PhD, and Kalanit Grill-Spector, PhD. The researchers recorded brain activity in epileptic patients who, because their seizures were unresponsive to drug therapy, had undergone a procedure in which a small section of the skulls was removed and plastic packets containing electrodes placed at the surface of the exposed brain. This was done so that, when seizures inevitably occurred, their exact point of origination could be identified. While  patients waited for this to happen, they gave the scientists consent to perform  an experiment.

In that experiment, selective electrical stimulation of another structure in the human brain, the fusiform gyrus, instantly caused a distortion in an experimental subjects’ perception of Parvizi’s face. So much so, in fact, that the subject exclaimed, “You just turned into somebody else. Your face metamorphosed!”

Like Wernicke’s and Broca’s area, the fusiform gyrus is found on each side of the brain. In animal species with brains fairly similar to our own, such as monkeys, stimulation of either the left or right fusiform gyrus appears to induce distorted face perception.

Yet, in a new study of ten such patients, conducted by Parvizi and colleagues and published in the Journal of Neuroscience,  face distortion occurred only when the right fusiform gyrus was stimulated. Other behavioral studies and clinical reports on patients suffering brain damage have shown a relative right-brain advantage in face recognition as well as a predominance of right-side brain lesions in patients with prosopagnosia, or face blindness.

Apparently, the left fusiform gyrus’s job description has changed in the course of our species’ evolution. Humans’ acquisition of language over evolutionary time, the Stanford investigators note, required the redirection of some brain regions’ roles toward speech processing. It seems one piece of that co-opted real estate was the left fusiform gyrus. The scientists suggest (and other studies hint) that along with the lateralization of language processing to the brain’s left hemisphere, face-recognition sites in that hemisphere may have been reassigned to new, language-related functions that nonetheless carry a face-processing connection: for example, retrieving the name of a person whose face you’re looking at, leaving the visual perception of that face to the right hemisphere.

My own right fusiform gyrus has been doing a bang-up job all my life and continues to do so. I wish I could say the same for my left side.

Previously: Metamorphosis: At the push of a button, a familiar face becomes a strange one, Mind-reading in real life: Study shows it can be done (but they’ll have to catch you first), We’ve got your number: Exact spot in brain where numeral recognition takes place revealed and Why memory and  math don’t mix: They require opposing states of the same brain circuitry
Photo by AlienGraffiti

Neuroscience, Research, Stanford News

Brain’s wiring more dynamic than originally thought

Brain's wiring more dynamic than originally thought

brain branches

I write a lot about news developments in which scientists learn new things about the body – how diseases develop or can be treated, how genes and proteins in our bodies make us who we are, how different areas of the brain work together to help us learn, remember and interact with our environment.

Yesterday I wrote a story in which the scientists learned that they have more work to do.

It all started when Joanna Mattis was looking for a PhD project. She had been working  in the lab of bioengineer Karl Deisseroth, MD, PhD, helping to develop optogenetics. At the time, that was an entirely new tool that scientists could use to turn parts of the brain on and off to see what happens. Mattis wanted to use optogenetics to map the wiring of two regions of the brain that were known to work together to help develop a spatial map of the environment. Those two regions are known as the hippocampus and the septum.

Some of the expertise needed to do this project didn’t exist in the Deisseroth lab. Mattis got a fellowship through Stanford Bio-X that specifically allows students to work with multiple mentors  – Mattis added neuroscientist John Huguenard, PhD, – bringing interdisciplinary expertise together to solve problems. In this case, those combined expertise didn’t so much solve a problem as create a new one.

What they found is that nerves in the hippocampus create one reaction in the septum if they fire slowly and a completely different reaction of they fire quickly. It was like learning that the wiring diagram of the brain shifts depending on how the brain sends signals.

Mattis told me, “There’s a lot of excitement about being able to make a map of the brain with the idea that if we could figure out how it is all connected we could understand how it works. It turns out it’s so much more dynamic than that.”

She said that next steps will include learning how widespread this type of wiring is throughout the brain, and understanding how it ties back to learning and memory.

Previously: Optogenetics: Offering new insights into brain disorders
Photo by nednapa/Shutterstock

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