neurosciencestuff:

For combat veterans suffering from post-traumatic stress disorder, ‘fear circuitry’ in the brain never rests

Chronic trauma can inflict lasting damage to brain regions associated with fear and anxiety. Previous imaging studies of people with post-traumatic stress disorder, or PTSD, have shown that these brain regions can over-or under-react in response to stressful tasks, such as recalling a traumatic event or reacting to a photo of a threatening face. Now, researchers at NYU School of Medicine have explored for the first time what happens in the brains of combat veterans with PTSD in the absence of external triggers.

Their results, published in Neuroscience Letters, and presented today at the annual meeting of the American Psychiatry Association in San Francisco, show that the effects of trauma persist in certain brain regions even when combat veterans are not engaged in cognitive or emotional tasks, and face no immediate external threats. The findings shed light on which areas of the brain provoke traumatic symptoms and represent a critical step toward better diagnostics and treatments for PTSD.

A chronic condition that develops after trauma, PTSD can plague victims with disturbing memories, flashbacks, nightmares and emotional instability. Among the 1.7 million men and women who have served in the wars in Iraq and Afghanistan, an estimated 20% have PTSD. Research shows that suicide risk is higher in veterans with PTSD. Tragically, more soldiers committed suicide in 2012 than the number of soldiers who were killed in combat in Afghanistan that year.

“It is critical to have an objective test to confirm PTSD diagnosis as self reports can be unreliable,” says co-author Charles Marmar, MD, the Lucius N. Littauer Professor of Psychiatry and chair of NYU Langone’s Department of Psychiatry. Dr. Marmar, a nationally recognized expert on trauma and stress among veterans, heads The Steven and Alexandra Cohen Veterans Center for the Study of Post-Traumatic Stress and Traumatic Brain Injury at NYU Langone Medical Center.

The study, led by Xiaodan Yan, a research fellow at NYU School of Medicine, examined “spontaneous” or “resting” brain activity in 104 veterans of combat from the Iraq and Afghanistan wars using functional MRI, which measures blood-oxygen levels in the brain. The researchers found that spontaneous brain activity in the amygdala, a key structure in the brain’s “fear circuitry” that processes fearful and anxious emotions, was significantly higher in the 52 combat veterans with PTSD than in the 52 combat veterans without PTSD. The PTSD group also showed elevated brain activity in the anterior insula, a brain region that regulates sensitivity to pain and negative emotions.

Moreover, the PTSD group had lower activity in the precuneus, a structure tucked between the brain’s two hemispheres that helps integrate information from the past and future, especially when the mind is wandering or disengaged from active thought. Decreased activity in the precuneus correlates with more severe “re-experiencing” symptoms—that is, when victims re-experience trauma over and over again through flashbacks, nightmares and frightening thoughts.

(via scinerds)

science-junkie:

The Moral Brain

Consider a failed murder attempt. Or a simple mistake that causes another to die. Is one of these more acceptable than the other?

Neuroscientists don’t pretend to hold the answers as to how people know what is right and what is wrong. But studies show individual biology may influence the ways people process the actions of others.

It turns out we judge others not only for what they do, but also for what we perceive they are thinking while they do it… “Often, what determines moral blame is not what the outcome is, but what [we think] is going on in the mind of the person performing the act,” says Rebecca Saxe, a neuroscientist at the Massachusetts Institute of Technology who studies how the brain casts judgment.
 
One way scientists study how we make right-or-wrong judgments is to look at brain regions that are most active when people attempt to interpret the thoughts of others.

In some studies, participants read stories about characters that either accidentally or intentionally cause harm to others while scientists use functional magnetic resonance imaging (fMRI) to track how brain activity changes. Such studies show that thinking about another’s thoughts increases the activity of nerve cells in a brain region known as the right temporo-parietal junction located behind the right ear.

As it turns out, some of these cells respond differently when presented with an intentional harm versus an accident. By zeroing in on the distinct patterns of activity in these cells, Saxe’s group discovered that they could accurately predict how forgiving the participants would be.

Full Article

(via neuromorphogenesis)

neurosciencestuff:

NSF-funded Superhero Supercomputer Helps Battle Autism

‘Gordon,’ a supercomputer with unique flash memory, helps identify gene-related paths to treating mental disorders

When it officially came online at the San Diego Supercomputer Center (SDSC) in early January 2012, Gordon was instantly impressive. In one demonstration, it sustained more than 35 million input/output operations per second—then, a world record.

Input/output operations are an important measure for data intensive computing, indicating the ability of a storage system to quickly communicate between an information processing system, such as a computer, and the outside world. Input/output operations specify how fast a system can retrieve randomly organized data common in large datasets and process it through data mining applications.

The supercomputer’s record-breaking feat wasn’t a surprise; after all, Gordon is named after a comic strip superhero, Flash Gordon.

Gordon’s new and unique architecture employs massive amounts of the type of flash memory common in cell phones and laptops—hence its name. The system is used by scientists whose research requires the mining, searching and/or creating of large databases for immediate or later use, including mapping genomes for applications in personalized medicine and examining computer automation of stock trading by investment firms on Wall Street.

Commissioned by the National Science Foundation (NSF) in 2009 for $20 million, Gordon is part of NSF’s Extreme Science and Engineering Discovery Environment, or XSEDE program, a nationwide partnership comprising 16 high-performance computers and high-end visualization and data analysis resources.

“Gordon is a unique machine in NSF’s Advanced Cyberinfrastructure/XSEDE portfolio,” said Barry Schneider, NSF program director for advanced cyberinfrastructure. “It was designed to handle scientific problems involving the manipulation of very large data. It is differentiated from most other resources we support in having a large solid-state memory, 4 GB per core, and the capability of simulating a very large shared memory system with software.”

Last month, a team of researchers from SDSC, the United States and the Institute Pasteur in France reported in the journal Genes, Brain and Behavior that they used Gordon to devise a novel way to describe a time-dependent gene-expression process in the brain that can be used to guide the development of treatments for mental disorders such as autism-spectrum disorders and schizophrenia.

The researchers identified the hierarchical tree of coherent gene groups and transcription-factor networks that determine the patterns of genes expressed during brain development. They found that some “master transcription factors” at the top level of the hierarchy regulated the expression of a significant number of gene groups.

The scientists’ findings can be used for selection of transcription factors that could be targeted in the treatment of specific mental disorders.

“We live in the unique time when huge amounts of data related to genes, DNA, RNA, proteins, and other biological objects have been extracted and stored,” said lead author Igor Tsigelny, a research scientist with SDSC as well as with UC San Diego’s Moores Cancer Center and its Department of Neurosciences.

“I can compare this time to a situation when the iron ore would be extracted from the soil and stored as piles on the ground. All we need is to transform the data to knowledge, as ore to steel. Only the supercomputers and people who know what to do with them will make such a transformation possible,” he said.

(via thescienceofreality)

neuromorphogenesis:

Why teenagers really do need an extra hour in bed

“MAKING teens start school in the morning is ‘cruel’, brain doctor claims.” So declared a British newspaper headline in 2007 after a talk I gave at an academic conference. One disbelieving reader responded: “This man sounds brain-dead.”

That was a typical reaction to work I was reporting at the time on teenage sleep patterns and their effect on performance at school. Six years on there is growing acceptance that the structure of the academic day needs to take account of adolescent sleep patterns. The latest school to adopt a later start time is the UCL Academy in London; others are considering following suit.

So what are the facts about teenage slumber, and how should society adjust to these needs?

The biology of human sleep timing, like that of other mammals, changes as we age. This has been shown in many studies. As puberty begins, bedtimes and waking times get later. This trend continues until 19.5 years in women and 21 in men. Then it reverses. At 55 we wake at about the time we woke prior to puberty. On average this is two hours earlier than adolescents. This means that for a teenager, a 7 am alarm call is the equivalent of a 5 am start for a person in their 50s.

Precisely why this is so is unclear but the shifts correlate with hormonal changes at puberty and the decline in those hormones as we age.

However, biology is only part of the problem. Additional factors include a more relaxed attitude to bedtimes by parents, a general disregard for the importance of sleep, and access to TVs, DVDs, PCs, gaming devices, cellphones and so on, all of which promote alertness and eat into time available for sleep.

The amount of sleep teenagers get varies between countries, geographic region and social class, but all studies show they are going to bed later and not getting as much sleep as they need because of early school starts.

Mary Carskadon at Brown University in Providence, Rhode Island, who is a pioneer in the area of adolescent sleep, has shown that teenagers need about 9 hours a night to maintain full alertness and academic performance. My own recent observations at a UK school in Liverpool suggested many were getting just 5 hours on a school night. Unsurprisingly, teachers reported students dozing in class.

Evidence that sleep is important is overwhelming. Elegant research has demonstrated its critical role in memory consolidation and our ability to generate innovative solutions to complex problems. Sleep disruption increases the level of the stress hormone cortisol. Impulsive behaviours, lack of empathy, sense of humour and mood are similarly affected.

All in all, a tired adolescent is a grumpy, moody, insensitive, angry and stressed one. Perhaps less obviously, sleep loss is associated with metabolic changes. Research has shown that blood-glucose regulation was greatly impaired in young men who slept only 4 hours on six consecutive nights, with their insulin levels comparable to the early stages of diabetes.

Similar studies have shown higher levels of the hormone ghrelin, which promotes hunger, and lower levels of leptin, which creates a sense of feeling full. The suggestion is that long-term sleep deprivation might be an important factor in predisposing people to conditions such as diabetes, obesity and hypertension.

Adolescents are increasingly using stimulants to compensate for sleep loss, and caffeinated and/or sugary drinks are the usual choice. The half-life of caffeine is 5 to 9 hours. So a caffeinated drink late in the day delays sleep at night. Tiredness also increases the likelihood of taking up smoking.

Collectively, a day of caffeine and nicotine consumption, the biological tendency for delayed sleep and the increased alertness promoted by computer or cellphone use generates what Carskadon calls a “perfect storm” for delayed sleep in teenagers.

In the US, the observation that teenagers have biologically delayed sleep patterns compared to adults prompted several schools to put back the start of the school day. An analysis of the impact by Kyla Wahlstrom at the University of Minnesota found that academic performance was enhanced, as was attendance. Sleeping in class declined, as did self-reported depression.

In the UK, Monkseaton High School near Newcastle instituted a 10 am start in 2009 and saw an uptick in academic performance.

However, a later start by itself is not enough. Society in general, and teenagers in particular, must start to take sleep seriously.

Sleep is not a luxury or an indulgence but a fundamental biological need, enhancing creativity, productivity, mood and the ability to interact with others.

If you are dependent upon an alarm clock, or parent, to get you out of bed; if you take a long time to wake up; if you feel sleepy and irritable during the day; if your behaviour is overly impulsive, it means you are probably not getting enough sleep. Take control. Ensure the bedroom is a place that promotes sleep – dark and not too warm – don’t text, use a computer or watch TV for at least half an hour before trying to sleep and avoid bright lights. Try not to nap during the day, and seek out natural light in the morning to adjust the body clock and sleep patterns to an earlier time. Avoid caffeinated drinks after lunch.

It is my strongly held view, based upon the evidence, that the efforts of dedicated teachers and the money spent on school facilities will have a greater impact and education will be more rewarding when, collectively, teenagers, parents, teachers and school governors start to take sleep seriously. In the universal language of school reports: we must do better.

neuromorphogenesis:

Building a Better Brain

The next generation of brain-machine interfaces (B-MI) may rapidly enhance health and improve the quality of life for those with reduced function due to disease or disability. They may also allow people to control drones with just their thoughts or even add new human senses, which raise important ethical considerations.

At the recent meeting of the American Association for the Advancement for Science in Boston, neuroscientists outlined several lines of promising B-MI research. Advances in microprocessors, computing, and materials science, for example, have facilitated the development of “epidermal electronics,” which combine wireless communications, neural sensors, and other medical sensors into patches small and flexible enough to serve as temporary tattoos. These electronics have obvious clinical use, such as for unobtrusive monitoring of vital signs or symptoms of brain disease, said principal investigator Todd P. Coleman of the University of California, San Diego. In fact, he has created a company, Neuroverse, to commercialize this type of application. But Coleman also sees more wide-ranging deployment in the near future. His work was partially inspired by previous experiments in which people controlled virtual or model airplanes via a cap of electrodes; flexible B-MIs might provide similar abilities without tying people down to bulky electronics. Applying the tattoos near the vocal cords might also allow for subvocal wireless communication with electronics such as smartphones. “The things you can pick up non-invasively are much richer than you might imagine at first glance,” he said. “Things we thought were hoaxes and science fiction are fast approaching fruition.”

And that may only be the tip of the iceberg: Miguel Nicolelis and his colleagues at Duke University have developed a means to create entirely new sense modalities. They connected infrared light sensors to dense three-dimensional arrays of electrodes implanted into the somatosensory cortex of rats. This allowed the rats to track food by “feeling” light that they physiologically have no way to detect. Think of it as an artificially induced form of synesthesia, Nicolelis said. “The rats learned to ‘touch’ a source of invisible light — they acquired new modality of touch.” The researchers have already extended the research to monkeys, raising the possibility that people might eventually be able to “augment” themselves with new abilities using this technology. “When you deliver signals from devices directly to brain,” Nicolelis said, “you can create a new sensation, a new feeling.”

The ethical implications of these B-MI projects and similar technology were not lost on session participants. All medical innovations raise legal and moral questions, said neuroethicist Martha Farah of the University of Pennsylvania. However, B-MI and other fields such as neuropsychiatry that directly affect people’s abilities raise particularly difficult questions about what it means to be human and what kind of relationship people have with technology. It’s difficult not to draw on iconic images of cyborgs from science fiction when discussing the long-term possibilities of B-MIs, which might include providing people new ways to sense the world, methods of augmenting cognition and memory, and even the ability to communicate brain-to-brain or merge identities.

“Ethical considerations such as those raised in the B-MI panel are important for all scientists,” said Michael Zigmond, professor of neurology at the University of Pittsburgh and secretary of the AAAS Neuroscience Section. “As scientific development and technological advances increasingly change the ways we deal with the human condition, we must continue to have conversations about how those changes might affect society. Such discussions are well-informed by the wide array of scientists who attend the AAAS annual meeting and can provide valuable insights and guidance.”

Additionally, Farah noted that focusing only on “sexy sci-fi long-term issues” ignores many serious short-term challenges more relevant to the day-to-day life of brain researchers and policymakers. “I’m not dismissing concerns about radically altered human brains that push us beyond what a human being is,” she said. “Before we get there, there are some other pretty serious ethical challenges — mundane, yet very important issues,” such as funding sources, conflicts of interest, and intellectual property protection. For example, rethinking clinical trial rules and practice might be necessary. In the United States, medical devices are regulated differently than pharmaceuticals, even though B-MIs are increasingly serving as a substitute for testing and treatment. Who funds current B-MI research may also have a disproportionate influence on the field, as aggressive pursuit of patents might constrain many promising avenues of research.

Between 10 and 30 years from now, people will need to make difficult decisions about access to B-MI technology, its appropriate uses, and risks, Farah added. Cochlear implants, retinal implants, and similar devices are already used regularly, but deciding what level of impairment is appropriate for treatment is not easy — especially as temptations grow to use this technology for frank enhancement or “making a person better than normal.” B-MIs that communicate wirelessly also expose people to hackers, computer viruses, and similar cybersecurity risks. “What if they hack into your brain?” Farah asked. With B-MIs, such inference could affect eyesight, memory, or even vital functions such as heart rate. People will also have to decide how to manage the costs of B-MI technology to ensure fair access. “Undoubtedly these technologies will be available to the rich before anyone else,” Farah said. “How would we like our society to manage these? How much do we guide the scientists and the health system to enforce as much equity as we can?”

(image: At the recent meeting of the American Association for the Advancement for Science in Boston, neuroscientists outlined several lines of promising brain-machine interface research.)

neuromorphogenesis:

Mom’s love good for child’s brain

School-age children whose mothers nurtured them early in life have brains with a larger hippocampus, a key structure important to learning, memory and response to stress.

The new research, by child psychiatrists and neuroscientists at Washington University School of Medicine in St. Louis, is the first to show that changes in this critical region of children’s brain anatomy are linked to a mother’s nurturing.

Their research is published online in theProceedings of the National Academy of SciencesEarly Edition.

“This study validates something that seems to be intuitive, which is just how important nurturing parents are to creating adaptive human beings,” says lead author Joan L. Luby, MD, professor of child psychiatry. “I think the public health implications suggest that we should pay more attention to parents’ nurturing, and we should do what we can as a society to foster these skills because clearly nurturing has a very, very big impact on later development.”

The brain-imaging study involved children ages 7 to 10 who had participated in an earlier study of preschool depression that Luby and her colleagues began about a decade ago. That study involved children, ages 3 to 6, who had symptoms of depression, other psychiatric disorders or were mentally healthy with no known psychiatric problems.

As part of the initial study, the children were closely observed and videotaped interacting with a parent, almost always a mother, as the parent was completing a required task, and the child was asked to wait to open an attractive gift. How much or how little the parent was able to support and nurture the child in this stressful circumstance — which was designed to approximate the stresses of daily parenting — was evaluated by raters who knew nothing about the child’s health or the parent’s temperament.

“It’s very objective,” Luby says. “Whether a parent was considered a nurturer was not based on that parent’s own self-assessment. Rather, it was based on their behavior and the extent to which they nurtured their child under these challenging conditions.”

The study didn’t observe parents and children in their homes or repeat stressful exercises, but other studies of child development have used similar methods as valid measurements of whether parents tend to be nurturers when they interact with their children.

For the current study, the researchers conducted brain scans on 92 of the children who had had symptoms of depression or were mentally healthy when they were studied as preschoolers. The imaging revealed that children without depression who had been nurtured had a hippocampus almost 10 percent larger than children whose mothers were not as nurturing.

“For years studies have underscored the importance of an early, nurturing environment for good, healthy outcomes for children,” Luby says. “But most of those studies have looked at psychosocial factors or school performance. This study, to my knowledge, is the first that actually shows an anatomical change in the brain, which really provides validation for the very large body of early childhood development literature that had been highlighting the importance of early parenting and nurturing. Having a hippocampus that’s almost 10 percent larger just provides concrete evidence of nurturing’s powerful effect.”

Luby says the smaller volumes in depressed children might be expected because studies in adults have shown the same results. What did surprise her was that nurturing made such a big difference in mentally healthy children.

“We found a very strong relationship between maternal nurturing and the size of the hippocampus in the healthy children,” she says.

Although 95 percent of the parents whose nurturing skills were evaluated during the earlier study were biological mothers, the researchers say that the effects of nurturing on the brain are likely to be the same for any primary caregiver — whether they are fathers, grandparents or adoptive parents.

The fact that the researchers found a larger hippocampus in the healthy children who were nurtured is striking, Luby says, because the hippocampus is such an important brain structure.

When the body faces stresses, the brain activates the autonomic nervous system, an involuntary system of nerves that controls the release of stress hormones. Those hormones help us cope with stress by increasing the heart rate and helping the body adapt. The hippocampus is the main brain structure involved in that response. It’s also key in learning and memory, and larger volumes would suggest a link to improved performance in school, among other things.

Past animal studies have indicated that a nurturing mother can influence brain development, and many studies in human children have identified improvements in school performance and healthier development in children raised in a nurturing environment. But until now, there has not been solid evidence linking a nurturing parent to changes in brain anatomy in children.

“Studies in rats have shown that maternal nurturance, specifically in the form of licking, produces changes in genes that then produce changes in receptors that increase the size of the hippocampus,” Luby says. “That phenomenon has been replicated in primates, but it hasn’t really been clear whether the same thing happens in humans. Our study suggests a clear link between nurturing and the size of the hippocampus.”

She says educators who work with families who have young children may improve school performance and child development by not only teaching parents to work on particular tasks with their children but by showing parents how to work with their children.

“Parents should be taught how to nurture and support their children,” Luby says. “Those are very important elements in healthy development.”

(Image: The hippocampus (highlighted in fuchsia) is a key brain structure important to learning, memory and stress response. New research shows that children who were nurtured by their mothers early in life have a larger hippocampus than children who were not nurtured as much. Credit: Washington University Medical School from press release)

(Source: news.wustl.edu)

neurosciencestuff:

New Research Shows Music Improves Health and Disease

Music has been incorporated into medical practice since before the ancient Greeks. However, though practitioners have been convinced of music’s health benefits for thousands of years, there had been little peer-reviewed research to back them up. But recent studies are providing an empirical backbone for the anecdotal evidence. A 2012 scientific review, published in the journal Nutrition, collects information from a number of studies to support music’s influence on the hypothalamic-pituitary-adrenal (HPA) axis, the sympathetic nervous system (SNS) and the immune system. These results support the experiences of complementary practitioners, who have long used music to help heal.

“As an integrative physician and traditional Chinese medicine practitioner, the healing power of music has always been an important part of my practice and family life,” says integrative medicine pioneer Isaac Eliaz, M.D. “Harmony and tempo help synchronize the rhythms of the natural world with the music of the heart – each person’s individual energetic pattern, expressed in their pulse.”

Proven Medicine
The review highlighted a number of studies that confirm music’s healing potential. For example, music reduces levels of serum cortisol in the blood. An important player in the HPA axis, cortisol increases metabolic activity, suppresses the immune system and has been associated with both anxiety and depression. A number of studies have shown that exposing post-operative patients to music dramatically lowers their cortisol levels, enhancing their ability to heal.

Other studies in the review measured music’s impact on congestive heart failure, premature infants, immunity, digestive function and pain perception. In particular, music’s effects on the limbic and hypothalamic systems reduced the incidence of heart failure. Other studies showed that surgical patients required less sedation and post-operative pain medication.

“These results only confirm what I have observed for many years in my practice,” says Dr. Eliaz. “Music produces quantifiable healing. For example, my daughter Amity, a professional musician, regularly plays her songs for chronically ill patients who express how uplifting her music is. These performances do more than encourage good feelings, they help the body heal on a molecular level.”

Powerful Impact
Perhaps the most interesting aspect of music’s healing properties is how widespread they are. For example, music also aided recovery time following strenuous exercise. Other studies showed that fast-paced music can increase resting metabolism, which may prove helpful for people trying to lose weight.

“Modern science has just begun to scratch the surface of music and sound in terms of healing potential,” says Dr. Eliaz. “However, traditional medical systems from around the world have long revered the beneficial vibrations of music, harmony and rhythm for health and vitality. The effects are instant and tangible, but they are also powerful and long lasting.”

(via stufftoblowyourmind)

jtotheizzoe:

EyeWire: You Play a Game, Scientists Map Neurons

Everyone wins! You guys should really check out EyeWire, an online game that helps you map neurons without any knowledge of biology. It’s revolutionary neuroscience, harnessing the power of thousands of video gamers to do a job that supercomputers can barely do.

EyeWire is a citizen science game created by MIT’s Sebastian Seung and friends (shout out to Amy from the Seung group for showing me this game!). Seung, famous for his work on the connectome (and the book of the same name), studies how mapping the nervous system’s connections help us define its true function. Understanding how our nervous system works requires knowing more than how one neuron works, we have to understand how they connect to each other to create larger networks. 

In EyeWire, you tour through pattern-filled cubes, clicking colored blobs to help the software map the arms of J cells (that’s one above), a type of neuron in the retina whose connections are very poorly understood. It’s seriously addictive, and you’ll be making a real difference in our understanding of the brain.

So why make a game? This kind of pattern recognition is very hard for computers to do. The human brain is amazingly adept at picking out patterns, far better than even our most powerful machines. 

My only minor complaint is that its popularity is making gameplay a little slow this first week. The great I F*cking Love Science Facebook page helped crash their servers yesterday, which are now back up, but new players are only being allowed in a handful at a time. So follow EyeWire on Facebook to find out when you can sign up. You’ll be glad you did.

I’m sure that the hordes of It’s Okay To Be Smart and other Tumblr science readers can crash the servers better than any Facebook page can, right?

Game on!