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Beyond Good And Evil: New Science Casts Light On Morality In The Brain

Harvard brain scientist Joshua Buckholtz has never forgotten a convict he met back when he was an undergrad conducting psychological tests in prisons. The man had beaten another man nearly to death for stepping on his foot in a dance club.

“I wanted to ask him,” he recalls, “‘In what world was the reward of beating this person so severely, for this — to me — minor infraction, worth having terrible food and barbed wire around you?’ ”

But over the years, Buckholtz became convinced that this bad deed was a result of faulty brain processing, perhaps in a circuit called the frontostriatal dopamine system. In an impulsive person’s brain, he says, attention just gets so narrowly focused on an immediate reward that, in effect, the future disappears.

He explains: “If you had asked this person, ‘What will happen if you beat someone nearly to death?’, they will tell you, ‘Oh, I’ll be put away.’ It’s not that these people who commit crimes are dumb, but what happens is, in the moment, that information about costs and consequences can’t get in to their decision-making.”

For two decades, researchers have scanned and analyzed the brains of psychopaths and murderers, but they haven’t pinpointed any single source of evil in the brain. What they’ve found instead, as Buckholtz puts it, “is that our folk concepts of good and evil are much more complicated, and multi-faceted, and riven with uncertainty than we ever thought possible before.”

In other words, so much for the old idea that we have an angel on one shoulder and a devil on the other, and that morality is simply a battle between the two. Using new technology, brain researchers are beginning to tease apart the biology that underlies our decisions to behave badly or do good deeds. They’re even experimenting with ways to alter our judgments of what is right and wrong, and our deep gut feelings of moral conviction.

One thing is certain: We may think in simple terms of “good” and “evil,” but that’s not how it looks in the brain at all.

In past years, as neuroscientists and psychologists began to delve into morality, “Many of us were after a moral center of the brain, or a particular system or circuit that was responsible for all of morality,” says assistant professor Liane Young, who runs The Morality Lab at Boston College. But “it turns out that morality can’t be located in any one area, or even set of areas — that it’s all over, that it colors all aspects of our life, and that’s why it takes up so much space in the brain.”

So there’s no “root of all evil.” Rather, says Buckholtz, “When we do brain studies of moral decision-making, what we are led into is an understanding that there are many different paths to antisocial behavior.”

If we wanted to build antisocial offenders, he says, brain science knows some of the recipe: They’d be hyper-responsive to rewards like drugs, sex and status — and the more immediate, the better. “Another thing we would build in is an inability to maintain representations of consequences and costs,” he says. “We would certainly short-circuit their empathic response to other people. We would absolutely limit their ability to regulate their emotions, particularly negative emotions like anger and fear.”

At his Harvard lab, Buckholtz is currently studying the key ability that long-ago convict lacked — to weigh future consequence against immediate gratification. In one ongoing experiment (see the video above), he’s testing whether he can use electrical stimulation to alter people’s choices. Continue reading

In Search Of ‘Computational Psychiatry:’ Why Is It A Hot New Field?

By Suzanne Jacobs
WBUR Intern

It’s around 10 a.m. on a weekday when I walk into a coffee shop that apparently doubles as the preferred study spot of every student on the Boston University campus. My instinct is to leave immediately and find a quieter place to caffeinate, but I’m not here for the coffee. I’m here for information — information on what I’m hearing is one of the hottest new trends in brain science.

Winding my way through tables of frazzled co-eds, I search every face for that “Are you who I’m looking for?” stare, but no one acknowledges me. So I step back out onto the sidewalk and wait. I’m early anyway.

About five minutes later, a young man who would have otherwise been indistinguishable from the crowd of students locks eyes with me from about 20 feet away. “That’s my guy,” I think to myself.

Lights of Ideas (Andrew Ostrovsky)

(Andrew Ostrovsky)

Minutes later, coffees in hand, we’re seated at a small back table, and I put my digital recorder down on it. “Is it okay if I record this?” I ask. He says that’s fine.

At this point, what I really want to do is grab him by the shoulders and yell, “What are you people doing? Let me into your world!” For weeks, I’ve been looking into this new field of research called computational psychiatry, but for the life of me, I can’t figure out what it is. More frustratingly, I can’t figure out why I can’t figure it out, despite a strong science background and hours of reading what little I could find about the topic on the Internet.

But I hold back, press the little red circle on my digital recorder and let the man speak.

In computational psychiatry, “What you try to do is come up with a toy world…,” he begins.

This all started a few weeks earlier when I was perusing the latest edition of Current Opinion in Neurobiology. Don’t ask me why I was perusing Current Opinion in Neurobiology — I don’t know. To avoid doing something else, probably.

One article caught my eye. It was titled “Computational approaches to psychiatry.” A longtime subscriber to the drugs-and-therapy stereotype of psychiatry, I found the idea of new “computational approaches” intriguing, so I read on. Continue reading

‘I’m Not Stupid, Just Dyslexic’ — And How Brain Science Can Help

Sixth-grader Josh Thibeau has been struggling to read for as long as he can remember. He has yet to complete a single Harry Potter book, his personal goal.

Growing up with dyslexia: Josh Thibeau, 12, imagines his brain as an ever-changing maze with turns he must learn to navigate. Here he is with his mother, Janet. (George Hicks/WBUR)

Growing up with dyslexia: Josh Thibeau, 12, thinks of his brain as an ever-changing maze with turns he must learn to navigate. Here he is with his mom, Janet. (George Hicks/WBUR)

When he was in first grade, Josh’s parents enrolled him in a research study at Boston Children’s Hospital investigating the genetics of dyslexia. Since then, Josh has completed regular MRI scans of his brain. Initially, it seemed daunting.

“When we first started, I’m like, ‘Oh no, you’re sending me to like some strange, like, science lab where I’m going to be injected with needles and it’s going to hurt,’ I’m like, ‘I’m never going to see my family again,’ ” says Josh, who lives in West Newbury, Mass.

Josh and his three biological siblings all have dyslexia to varying degrees. Pretty much every day he confronts the reality that his brain works differently than his peers’. He’s even shared scans of his brain with classmates to try to show those differences. Some kids still don’t get it.

“There was a student that said, ‘Are you stupid?’ Because my brain was working in a different way,” Josh says. “And I’m just like, ‘No, I am not stupid…I’m just dyslexic.’ ”

The Pre-Reading Brain 

On average, one or two kids in every U.S. classroom has dyslexia, a brain-based learning disability that often runs in families and makes reading difficult, sometimes painfully so.

Compared to other neurodevelopmental disorders like ADHD or autism, research into dyslexia has advanced further, experts say. That’s partly because dyslexia presents itself around a specific behavior: reading — which, as they say, is fundamental.

Now, new research shows it’s possible to pick up some of the signs of dyslexia in the brain even before kids learn to read. And this earlier identification may start to substantially influence how parents, educators and clinicians tackle the disorder.

Until recently (and sometimes even today) kids who struggled to read were thought to lack motivation or smarts. Now it’s clear that’s not true: Dyslexia stems from physiological differences in the brain circuitry. Those differences can make it harder, and less efficient, for children to process the tiny components of language, called phonemes.

And it’s much more complicated than just flipping your “b’s and “d’s.” To read, children need to learn to map the sounds of spoken language — the “KUH”, the “AH”, the “TUH” — to their corresponding letters. And then they must grasp how those letter symbols, the “C” “A” and “T”, create words with meaning. Kids with dyslexia have far more trouble mastering these steps automatically.

For these children, the path toward reading is often marked by struggle, anxiety and feelings of inadequacy. In general, a diagnosis of dyslexia usually means that a child has experienced multiple failures at school.

But collaborations currently underway between neuroscientists at MIT and Children’s Hospital may mark a fundamental shift in addressing dyslexia, and might someday eliminate the anguish of repeated failure. In preliminary findings, researchers report that brain measures taken in kindergartners — even before the kids can read — can “significantly” improve predictions of how well, or poorly, the children can master reading later on.

Implicated in dyslexia: The arcuate fasciculus is an arch-shaped bundle of fibers that connects the frontal language areas of the brain to the areas in the temporal lobe that are important for language (left). Researchers found that kindergarten children with strong pre-reading scores have a bigger, more robust and well-organized arcuate fasciculus (bottom right) while children with very low scores have a small and not particularly well-organized arcuate fasciculus (top right). (Zeynep Saygin/MIT)

Implicated in dyslexia: The arcuate fasciculus is an arch-shaped bundle of fibers that connects the frontal language areas of the brain to the areas in the temporal lobe that are important for language (left). Researchers found that kindergarten children with strong pre-reading scores have a bigger, more robust and well-organized arcuate fasciculus (bottom right) while children with very low scores have a small and not particularly well-organized arcuate fasciculus (top right). (Zeynep Saygin/MIT)

Pinpointing The White Matter Culprit

Using cutting-edge MRI technology, the researchers are able to pinpoint a specific neural pathway, a white matter tract in the brain’s left hemisphere that appears to be related to dyslexia: It’s called the arcuate fasciculus.

“Maybe the most surprising aspect of the research so far is how clear a signal we see in the brains of children who are likely to go on to be poor readers.”
– MIT neuroscientist John Gabrieli

“It’s an arch-shaped bundle of fibers that connects the frontal language areas of the brain to the areas in the temporal lobe that are important for language,” Elizabeth Norton, a neuroscientist at MIT’s McGovern Institute of Brain Research, explains.

In her lab, Norton shows me brain images from the NIH-funded kindergartner study, called READ (for Researching Early Attributes of Dyslexia).

“We see that in children who in kindergarten already have strong pre-reading scores, their arcuate fasciculus is both bigger and more well organized,” she says. On the other hand: “A child with a score of zero has a very small and not particularly organized arcuate fasciculus.”

She says we’re not quite ready to simply take a picture of your child’s brain and say “Aha, this kid is going to have dyslexia,” but we’re getting closer to that point. Continue reading

Your Brain On Junk Food: ‘Making Us Crazy’ — But Might Fish Help?

By Suzanne E. Jacobs
CommonHealth intern

An urban planner and a biochemist walk into a seafood restaurant.

Okay, that joke’s going nowhere, but last week an urban planner and a biochemist did walk into a classroom at MIT. In a talk titled “Junk Food and the Modern Mind,” the unusual duo explained to a room full of people how seafood’s effects on the human brain could bridge their seemingly disparate fields.

The urban planner was Lynn Todman, a visiting scholar at MIT. Todman has spent the past nine years working to improve mental health and reduce violence among residents of some of Chicago’s roughest neighborhoods.

(Wikimedia Commons)

(Wikimedia Commons)

Last year, Todman held a focus group with adult men in Chicago. At one point, she recalled, one of the men said, “This food is making us crazy,” referring to the unhealthy options common in urban food deserts. Having read up on studies linking nutrition and aggression, Todman took what he said seriously.

“Now, I’ve been doing community based work for a long time, and I know that residents often understand social realities long before we do in the academy, and even though their understanding might be shaped by a series of anecdotes strung together to suggest a trend or pattern, I attribute very real meaning to what residents say about their communities and the observations about the world that they live in,” she said.

Enter Capt. Joe Hibbeln, the biochemist.

Hibbeln, who is also a psychiatrist, works at the National Institutes of Health as a nutritional neuroscientist and is one of the world’s leading experts on the role of fats in brain development.

His claim: a diet rich in omega-3 fatty acids and low in omega-6 fatty acids can make people happier and less aggressive. Continue reading

On Perception (And Pancakes): How The Brain Keeps Vision Stable

By Alexandra Morris
CommonHealth Intern

You probably didn’t think Julia Roberts could teach you much about subtle, yet critical, brain functions.

But, it turns out, she can. Recall Roberts in her iconic film “Pretty Woman.” In one scene, she is eating a croissant. But as the camera pans back to her, the croissant turned into a pancake.

It’s likely that many of us missed that blooper, and now we know why. Scientists have discovered a brain mechanism that smooths our field of vision so that we don’t notice certain subtle visual changes — such as a croissant becoming a pancake in an otherwise identical scene.

In a paper published last month in Nature Neuroscience, researchers from the University of California, Berkeley have identified a brain mechanism that helps to stabilize our field of vision. They call it, a “continuity field” — a process the brain uses to merge similar objects seen within a 15-second timeframe.

“It seems like a very odd thing the brain is doing that could make us less accurate,” said the study’s lead author, Jason Fischer, who is now a postdoctoral fellow in the Department of Brain and Cognitive Sciences at MIT. “But in fact there is this huge benefit to it — and that is stabilizing perception over time.”

To measure this process, researchers showed study participants an image with alternating light and dark bars, or “gratings,” at a random angle every five seconds. The participants were then asked to move a white bar to match the tilt of the grating that had been shown.

Here’s the video:

Researchers found that while the white bars generally aligned with the image, there were subtle differences that were biased toward the previous three or so images. These differences could be attributed to the continuity field.

Imagine, now, for example, you are driving down a highway in the pouring rain and you’re trying to read a road sign. The windshield wipers are moving; the raindrops are hitting your windshield. As you’re looking at the sign, you’re experiencing constant interruptions in your visual stream. In that case, the changes that the continuity field is causing us to miss are the raindrops and windshield wipers — you may even fail to notice them after a while. The continuity field, for the most part, is beneficial — it blocks the stuff we don’t want to see. Continue reading

Why To Exercise Today: It Even Appears To Help Your Eyes

(Wikimedia Commons)

(Wikimedia Commons)

God help us, when will it ever stop? Is there no organ, no medical condition, no tiny part of the human body that is not helped by exercise?

A new mouse study in the The Journal of Neuroscience finds that exercise appears to be good for the retina, and may even slow the development of age-related macular degeneration, which is estimated to affect nearly 2 million older Americans. The key appears to be a helpful protein called brain-derived neurotrophic factor. From the press release:

Moderate aerobic exercise helps to preserve the structure and function of nerve cells in the retina after damage, according to an animal study appearing February 12 in The Journal of Neuroscience. The findings suggest exercise may be able to slow the progression of retinal degenerative diseases.

Age-related macular degeneration, one of the leading causes of blindness in the elderly, is caused by the death of light-sensing nerve cells in the retina called photoreceptors. Although several studies in animals and humans point to the protective effects of exercise in neurodegenerative diseases or injury, less is known about how exercise affects vision.

Machelle Pardue, PhD, together with her colleagues Eric Lawson and Jeffrey H. Boatright, PhD, at the Atlanta VA Center for Visual and Neurocognitive Rehabilitation and Emory University, ran mice on a treadmill for two weeks before and after exposing the animals to bright light that causes retinal degeneration. The researchers found that treadmill training preserved photoreceptors and retinal cell function in the mice.

“This is the first report of simple exercise having a direct effect on retinal health and vision,” Pardue said. “This research may one day lead to tailored exercise regimens or combination therapies in treatments of blinding diseases.” Continue reading

Your Brain On Poverty: Low-Income Childhood Linked To Smaller Brain

Young children living in poverty appear to have smaller brain volumes in critical areas, according to researchers at Washington University School of Medicine. But poverty’s detrimental impact on brain development may be mediated by basic early interventions like compassionate parenting and caregiving, the report says.

(Digital Shotgun/flickr)

(Digital Shotgun/flickr)

Growing up poor is already known to be associated with a higher risk of “poor cognitive outcomes” and school performance, the researchers note. But what’s fairly new here is how outside economic forces play out in the development of a child’s brain. According to the study, published in JAMA Pediatrics Monday:

Poverty was associated with smaller white and cortical gray matter and hippocampal and amygdala volumes. The effects of poverty on hippocampal volume were mediated by caregiving support/hostility on the left and right, as well as stressful life events on the left.

The finding that exposure to poverty in early childhood materially impacts brain development at school age further underscores the importance of attention to the well-established deleterious effects of poverty on child development. Continue reading

The Genetics Of Autism: Inside The Brains Of The Supple Boys

Don’t miss Lynn Jolicoeur’s excellent piece on WBUR this morning about the genetics of autism and the two young Natick boys, Tommy and Stuart Supple, whose gene mutations are the focus of research by Stanford neuroscientist Dr. Thomas Sudhof.

(Jesse Costa/WBUR)

(Jesse Costa/WBUR)

From Lynn’s story:

…The Stanford University neuroscientist — who this year shared the Nobel Prize in medicine for his decades of study into how brain cells communicate — has been studying Tommy and Stuart’s genes, specifically an alteration in one gene, for five years. The Supples hosted Sudhof Wednesday night at a Boston fundraiser in support of his research into the functioning of brain synapses in autism…

According to the Supples, Sudhof’s work is helping conquer the “defeatism” surrounding the neurocognitive disorder.

“He doesn’t think this is unknowable at all. He thinks that it’s very knowable,” Kate Supple said. “We all put so much time and effort into dealing with the symptoms of autism. But you also have to look to deal with the underlying disease.”

For many parents of children with autism, the disorder is a mystery. They have no idea what caused it and focus on therapies to help address the symptoms. But after the blow of both boys being diagnosed before their 2nd birthdays, the Supples sought out private genetic testing without the encouragement of their doctors. Continue reading

Huh? Hunger Hormone May Be Key To Stress Effects On Mental Health

Dr. Ki Goosense and .....

Dr. Ki Goosens and Technical Associate Junmei Yao examine a piece of human brain at the McGovern Institute for Brain Research. They are looking for stress-sensitive genes that are abnormally activated in the amygdala — a brain region that regulates emotion — in people who committed suicide. (Courtesy Justin Knight Photography and McGovern Institute)

(Click the play button above for the audio version of this story.)

Neuroscientist Ki Goosens does her research with black and white rats, but what she has discovered could be very relevant to humans — including her own family.

In the last eight years, three family members have become suicidal in the wake of a “major life stressor” like divorce.

“For years, they were fine, and then it triggers some cascade of vulnerability,” she said. “So I feel a sense of urgency in trying to come up with new ways to think about how we can block the ability of stress to worsen mental illness, to trigger mental illness.”

Goosens and her team at MIT’s McGovern Institute for Brain Research have just published what could be a major lead: A hormone called ghrelin — known as the hunger hormone and made in the stomach — may be a key to post-traumatic stress disorder and other stress-related mental illnesses.

The research is still early, but it raises the possibility that drugs that block ghrelin could be used to block some of the mental harm done by chronic stress.

‘I’m a neuroscientist. I study the brain. But you sort of go where the data take you.’

Goosens and her collaborators at Mass. General Hospital are now planning two studies on ghrelin in humans: One will determine whether ghrelin levels are elevated in people with anxiety disorders; the other will block ghrelin signaling in hopes of preventing stress-related relapses of depression.

Goosens never expected to be using a hunger hormone to understand stress: “If you had asked me five years ago if I would be doing something related to the stomach, I would’ve said, ‘No way, you’re crazy. I’m a neuroscientist! I study the brain,’” she said. “But you sort of go where the data take you.”

She originally set out to explore how stress affects the activity of genes in the amygdala, a part of the brain that processes emotions. Continue reading

Nature: Recipe For A (Primitive Precursor Of A) Human Brain In A Jar

brainjar

So delicious! No, I don’t mean vat-grown brain pickles. I mean the delicious frisson I get every time real-life science news seems to echo long-beloved science fiction in uncanny ways.

So to today’s very serious report in the prestigious journal Nature: Researchers have found a way to build a sort of a human proto-brain in the lab. (Of course, their work, striking as it is, falls miles short of the classic cinematic depictions of brains in jars, but let’s just take a moment here to recall Steve Martin’s true love in “The Man With Two Brains,” and the ancient black-and-white sci-fi flicks featuring disembodied brains. “Brain in a jar” even has a whole page on tvtropes.org.)

Now to 2013 reality: The scientists, based mainly at the Institute of Molecular Biotechnology in Vienna, used stem cells to engineer a three-dimensional precursor of a human brain, about the size of a pea. They say this miniature proto-brain could help illuminate how the human brain develops — and what can go wrong as it does.

They grew the stem cells into a brain-like structure at about the level of a nine-week-old human embryo’s brain. And they showed that this primitive mini-brain could cast light on a specific disorder: microcephaly, a rare birth defect in which the brain doesn’t grow nearly as big as it should.

The work is still in very early stages, but the researchers say they hope it can also be used to help treat more common brain diseases that begin early in life, including schizophrenia and autism.

They began with human stem cells from adults, and helped them grow and self-organize into a primitive but strikingly brain-like structure, which they call a cerebral organoid. An organoid is a structure like an organ — so this isn’t a full-fledged brain, but if you consider that the human brain is known as the most complex organ in the animal kingdom, it’s still pretty impressive.

So what exactly is the recipe for whipping up a human brain? Continue reading