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What is dyslexia?

Was that text hard to read (referring to the first image)? That’s actually a simulation of the experience of dyslexia, designed to make you decode each word. Those with dyslexia experience that laborious pace every time they read.

The truth is, people with dyslexia see things the same way as everyone else. Dyslexia is caused by a phonological processing problem, meaning people affected by it have trouble not with seeing language, but with manipulating it.

Neurodiversity is the idea that because all of our brains show differences in structure and function, we shouldn’t be so quick to label every deviation from “the norm” as a pathological disorder or dismiss people living with these variations as “defective”.

fMRI studies have found that the brains of those with dyslexia rely more on the right hemisphere and frontal lobe than the brains of those without it. This means, when they read a word, it takes a longer trip through their brain and can get delayed in the frontal lobe. Because of this neurobiological glitch, they read with more difficulty.

But those with dyslexia can physically change their brain and improve their reading with an intensive, multi-sensory intervention that breaks the language down and teaches the reader to decode based on syllable types and spelling rules. The brains of those with dyslexia begin using the left hemisphere more efficiently while reading, and their reading improves.

Source: Ted-Ed

Learn more about dyslexia by watching the TED-Ed Lesson What is dyslexia? - Kelli Sandman-Hurley.  Animation by Marc Cristoforidis 

Redrawing the brain’s motor map

Neuroscientists at Emory have refined a map showing which parts of the brain are activated during head rotation, resolving a decades-old puzzle. Their findings may help in the study of movement disorders affecting the head and neck, such as cervical dystonia and head tremor.

The results were published in Journal of Neuroscience.

In landmark experiments published in the 1940s and 50s, Canadian neurosurgeon Wilder Penfield and colleagues determined which parts of the motor cortex controlled the movements of which parts of the body.

Penfield stimulated the brain with electricity in patients undergoing epilepsy surgery, and used the results to draw a “motor homunculus”: a distorted representation of the human body within the brain. Penfield assigned control of the neck muscles to a region between those that control the fingers and face, a finding inconsistent with some studies that came later.

Using modern functional MRI (magnetic resonance imaging), researchers at Emory University School of Medicine have shown that the neck’s motor control region in the brain is actually between the shoulders and trunk, a location that more closely matches the arrangement of the body itself.

“We can’t be that hard on Penfield, because the number of cases where he was able to study head movement was quite limited, and studying head motion as he did, by applying an electrode directly to the brain, creates some challenges,” says lead author Buz Jinnah, MD, professor of neurology, human genetics and pediatrics at Emory University School of Medicine.

The new location for the neck muscles makes more sense, because it corresponds to a similar map Penfield established of the sense of touch (the somatosensory cortex), Jinnah says.

Participants in brain imaging studies need to keep their heads still to provide accurate data, so volunteers were asked to perform isometric muscle contraction. They attempted to rotate their heads to the left or the right, even though head movement was restricted by foam padding and restraining straps.

First author Cecilia Prudente, a graduate student in neuroscience who is now a postdoctoral associate at the University of Minnesota, developed the isometric head movement task and obtained internal funding that allowed the study to proceed.

She and Jinnah knew that isometric exercises for the wrist activated the same regions of the motor cortex as wrist movements, and used that as a reference point in their study. During brain imaging, they were able to check that particular muscles were being tensed by directly monitoring volunteers’ muscles electronically.

When volunteers contracted their neck muscles, researchers were able to detect activation in other parts of the brain too, such as the cerebellum and the basal ganglia, which are known to be involved in movement control. This comes as no surprise, Jinnah says, since these regions also control movements of the hands and other body parts.

Prudente, Jinnah and colleagues have conducted a similar study with cervical dystonia patients, with the goal of comparing the patterns of brain activation between healthy volunteers and the patients. Cervical dystonia is a painful condition in which the neck muscles contract involuntarily and the head posture is distorted.

“These results may help guide future studies in humans and animals, as well as medical or surgical interventions for cervical dystonia and other disorders involving abnormal head movements,” Prudente says.

Intrusive Memories of Traumatic Events Reduced by Sleep Deprivation

A good night’s sleep has long been recommended to those who have experienced a traumatic event. But an Oxford University-led study provides preliminary experimental work suggesting it could actually be the wrong thing to do.

The research is in Sleep. (full access paywall)

Research: “Psychological Effect of an Analogue Traumatic Event Reduced by Sleep Deprivation” by Kate Porcheret, PhD; Emily A. Holmes, PhD; Guy M. Goodwin, FMedSci; Russell G. Foster, PhD; and Katharina Wulff, PhD in Sleep doi:10.5665/sleep.4802

Image: Each person then kept a diary in which they recorded any intrusive memories, however fleeting, recording as much information as possible so that the research team could check that the intrusive images were linked to the film. This image is for illustrative purposes only. Credit: Vic.

sciencedaily.com
Emotional brains 'physically different' from rational ones -- ScienceDaily

“People who are high on affective empathy are often those who get quite fearful when watching a scary movie, or start crying during a sad scene. Those who have high cognitive empathy are those who are more rational, for example a clinical psychologist counselling a client,” Mr Eres said.

The researchers used voxel-based morphometry (VBM) to examine the extent to which grey matter density in 176 participants predicted their scores on tests that rated their levels for cognitive empathy compared to affective – or emotional – empathy.

The results showed that people with high scores for affective empathy had greater grey matter density in the insula, a region found right in the ‘middle’ of the brain. Those who scored higher for cognitive empathy had greater density in the midcingulate cortex – an area above the corpus callosum, which connects the two hemispheres of the brain.

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Does hitting the snooze button help? - Big Questions - (Ep. 34)

This week, Mitra Mirpour asks, “Does hitting the snooze button and getting those few extra minutes of sleep actually help?”

By: Mental Floss.
Get Mental Floss merchandise (enter promo code: “YoutubeFlossers” for 15% off!)

Introverts & Extroverts Have Different Brains: Which One Are You?

Scientists have discovered that the brains of introverts are actually different from those of extroverts. This isn’t too surprising, especially considering all of the research now coming out of the field of neuroplasticity. It refers to various changes that can take place in the brain (including changes in neural pathways and synapses) as a result of shifts in things like: a person’s behaviour or environment; their perception of the environment around them; neural processes; the way they think and feel and more.

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Missing link found between brain, immune system — with major disease implications

In a stunning discovery that overturns decades of textbook teaching, researchers at the University of Virginia School of Medicine have determined that the brain is directly connected to the immune system by vessels previously thought not to exist.

That such vessels could have escaped detection when the lymphatic system has been so thoroughly mapped throughout the body is surprising on its own, but the true significance of the discovery lies in the effects it could have on the study and treatment of neurological diseases ranging from autism to Alzheimer’s disease to multiple sclerosis.

“Instead of asking, ‘How do we study the immune response of the brain?,’ ‘Why do multiple sclerosis patients have the immune attacks?,’ now we can approach this mechanistically – because the brain is like every other tissue connected to the peripheral immune system through meningeal lymphatic vessels,” said Jonathan Kipnis, a professor in U.Va.’s Department of Neuroscience and director of U.Va.’s Center for Brain Immunology and Glia. “It changes entirely the way we perceive the neuro-immune interaction. We always perceived it before as something esoteric that can’t be studied. But now we can ask mechanistic questions.“

He added, “We believe that for every neurological disease that has an immune component to it, these vessels may play a major role. [It’s] hard to imagine that these vessels would not be involved in a [neurological] disease with an immune component.”

Kevin Lee, who chairs the Department of Neuroscience, described his reaction to the discovery by Kipnis’ lab: “The first time these guys showed me the basic result, I just said one sentence: ‘They’ll have to change the textbooks.’ There has never been a lymphatic system for the central nervous system, and it was very clear from that first singular observation – and they’ve done many studies since then to bolster the finding – that it will fundamentally change the way people look at the central nervous system’s relationship with the immune system.”

Even Kipnis was skeptical initially. “I really did not believe there are structures in the body that we are not aware of. I thought the body was mapped,” he said. “I thought that these discoveries ended somewhere around the middle of the last century. But apparently they have not.

The discovery was made possible by the work of Antoine Louveau, a postdoctoral fellow in Kipnis’ lab. The vessels were detected after Louveau developed a method to mount a mouse’s meninges – the membranes covering the brain – on a single slide so that they could be examined as a whole. “It was fairly easy, actually,” he said. “There was one trick: We fixed the meninges within the skullcap, so that the tissue is secured in its physiological condition, and then we dissected it. If we had done it the other way around, it wouldn’t have worked.”

After noticing vessel-like patterns in the distribution of immune cells on his slides, he tested for lymphatic vessels and there they were. The impossible existed.

The soft-spoken Louveau recalled the moment: “I called Jony [Kipnis] to the microscope and I said, ‘I think we have something.’”

As to how the brain’s lymphatic vessels managed to escape notice all this time, Kipnis described them as “very well hidden” and noted that they follow a major blood vessel down into the sinuses, an area difficult to image. “It’s so close to the blood vessel, you just miss it,” he said. “If you don’t know what you’re after, you just miss it.

“Live imaging of these vessels was crucial to demonstrate their function, and it would not be possible without collaboration with Tajie Harris,” Kipnis noted. Harris is an assistant professor of neuroscience and a member of the Center for Brain Immunology and Glia. Kipnis also saluted the “phenomenal” surgical skills of Igor Smirnov, a research associate in the Kipnis lab whose work was critical to the imaging success of the study.

The unexpected presence of the lymphatic vessels raises a tremendous number of questions that now need answers, both about the workings of the brain and the diseases that plague it.

For example, take Alzheimer’s disease. “In Alzheimer’s, there are accumulations of big protein chunks in the brain,” Kipnis said. “We think they may be accumulating in the brain because they’re not being efficiently removed by these vessels.” He noted that the vessels look different with age, so the role they play in aging is another avenue to explore.

And there’s an enormous array of other neurological diseases, from autism to multiple sclerosis, that must be reconsidered in light of the presence of something science insisted did not exist.

Image:  The lymphatic system map: old (left) and new.

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Maternal Stress Alters Offspring Gut and Brain through Vaginal Microbiome

Changes in the vaginal microbiome are associated with effects on offspring gut microbiota and on the developing brain, according to a new study published in Endocrinology, a journal of the Endocrine Society.

The neonate is exposed to the maternal vaginal microbiota during birth, providing the primary source for normal gut colonization, host immune maturation, and metabolism. These early interactions between the host and microbiota occur during a critical window of neurodevelopment, suggesting early life as an important period of cross talk between the developing gut and brain.

“Mom’s stress during pregnancy can impact her offspring’s development, including the brain, through changes in the vaginal microbiome that are passed on during vaginal birth,” said one of the study’s authors, Tracy Bale, PhD, of the University of Pennsylvania. “As the neonate’s gut is initially populated by the maternal vaginal microbiome, changes produced by maternal stress can alter this initial microbe population as well as determine many aspects of the host’s immune system that are also established during this early period.”

In this study, researchers utilized an established mouse model of early maternal stress, which included intervals of exposure to a predator odor, restraint, and novel noise as stressors. Two days after birth, tissue was collected from the moms using vaginal lavages and maternal fecal pellets and offspring distal gut were analyzed. Offspring brains were examined to measure transport of amino acids. Researchers found stress during pregnancy was associated with disruption of maternal vaginal and offspring gut microbiota composition.

These findings demonstrate the important link between the maternal vaginal microbiome in populating her offspring’s gut at birth, and the profound effect of maternal stress experience on this microbial population and in early gut and brain development, especially in male offspring.

“These studies have enormous translational potential, as many countries are already administering oral application of vaginal lavages to c-section delivered babies to ensure appropriate microbial exposure occurs,” Bale said. “Knowledge of how maternal experiences such as stress during pregnancy can alter the vaginal microbiome is critical in determination of at-risk populations.”

sciencedaily.com
How your brain reacts to emotional information is influenced by your genes -- ScienceDaily

Your genes may influence how sensitive you are to emotional information, according to new research by a neuroscientist. The study found that carriers of a certain genetic variation perceived positive and negative images more vividly, and had heightened activity in certain brain regions.

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5 Best Ways To Cure Insomnia

Have trouble sleeping? Here are some ways to help you fix that.

Read more: How to Fix Broken Sleep

By: Think Tank.

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Most of us have experienced writer’s block at some point, sitting down to write, paint or compose only to find we can’t get the creative juices flowing. Most frustrating of all, the more effort and thought we put into it, the harder it may become. Now, at least, neuroscientists might have found a clue about why it is so hard to force that creative spark. Researchers at Stanford University recently set out to explore the neural basis of creativity and came up with surprising findings. Their study, published May 28 in Scientific Reports, suggests the cerebellum, the brain region typically associated with movement, is involved in creativity. 

New research suggests that when it comes to creativity, the less you think about the task at hand the better

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The Brain That Heals Itself: Neuroplasticity and Promise for Addiction Treatment

A woman sits at her piano, practicing a five-finger exercise. For two hours a day, she practices the exercise over and over, her finger movements growing sharper, more precise and fluid. Another woman sits in a chair, hands still, and imagines playing the same five-finger exercise. For two hours a day, she practices in her mind and she can visualize herself getting faster, more melodic, more purposeful. After five days, the motor cortex corresponding to these finger movements has flourished in the brain of the woman playing the piano, proving that behaviors physically alter the brain. But what is more fascinating is that these neural changes also occurred in the woman who was simply imagining playing the piano. In other words, we can change the structure of our brains simply by thinking.

The human brain has historically been a mysterious thing, a slippery and elusive being. For years it was thought that the brain completed its development early and then sat fixed, immutable, and vulnerable to damage from which it could not heal. Then an opera singer with MS regains his soaring voice. A blind man teaches himself to see. A man with Parkinson’s cures his symptoms by walking. And research begins to teach us that the brain is not static, but a flexible organ with the ability to form itself to behavior, reorganize itself to accommodate change, and compensate for damage. The brain is inventive, responsive, and, through careful modulation, full of promise.

The Changing Brain

As you think new thoughts, practice new skills, and participate in new behaviors, neural pathways form. As these thoughts and behaviors are repeated, the pathways strengthen, habits emerge, and the brain is rewired to invite the use of these roads. Like a well-worn forest trail we walk every day, we know them by feel, the memory of their twists is imprinted on us, their turns sewn into our consciousness. Meanwhile, pathways we no longer use weaken, become impassable and hostile in comparison to their more popular, open alternatives. This plastic nature of the brain – or neuroplasticity – opens up a world of potential for people to optimize their minds through improved cognitive function, memory, language skills, and guard against age-related decline. It also gives us a new way of conceptualizing addiction, and the promise of treatment possibilities to guide users to recovery using the innate resources of their own brains.

Addiction As A Brain Disorder

For years, debate has raged between schools of thought that frame addiction as a choice versus addiction as a disease. Through an understanding of the brain as an adaptable organ, we can reach a more sophisticated model, describing addiction as a reorientation of the brain that creates new neural pathways and perpetuates addictive behavior. Rather than arbitrary choice, the addict’s brain has remapped itself to make feeding addiction the most natural course of action.

When a person indulges in addictive behavior, their brain floods with dopamine. Dopamine release is not only highly rewarding, it also increases the ability to learn, and tells the brain, “Remember how this happened so you can feel this way again.” As the behavior is performed again and again, the level of dopamine release decreases, and new extremes must be reached for the same effect. Eventually, tolerance may build to such a point that the addictive behavior no longer provides pleasure at all–merely avoidance of withdrawal. But even in the face of diminished rewards, the neural pathways beg for the repetition of the behavior; the brain is now built for addiction.

The Power of Neuroplasticity

While neuroplasticity may be a culprit in the creation of addiction, it also holds the key to recovery. By harnessing the moldability of the brain and abandoning the neural connections fed by addictive behaviors, new pathways can be formed via the development of healthy behaviors and thought processes. Through carefully created treatment plans, people suffering from addiction can be released from its grip to move toward stability, insight, and self-awareness.

Meditation in particular is proven to engage the brain and expand its potential. Applying the principles of meditation to treatment addiction, Mindfulness-Based Relapse Prevention (MBRP) modulates brain activity to create new neural responses to distress and cravings. Through mindful meditation, people with addiction can learn to tolerate discomfort and stressful situations with decreased reactivity, allowing them to be in control of their actions and behave in thoughtful, deliberate ways. Even more significantly, MBRP allows addicts to experience distress without increased cravings, interrupting self-destructive impulses and replacing them with healthy coping mechanisms.

Toward Recovery

By embracing the potential of neuroplasticity and integrating neural modulation into therapeutic practice, addiction treatment programs can harness the healing powers of the brain and relieve suffering. This nuanced understanding of the brain offers hope for the millions of people suffering from addiction as we forge new paths to lasting sobriety. 

Put together by Alta Mira, an addiction treatment center in Los Angeles, California.

Researchers Discover New Epigenetic Mecahnism in Brain Cells

Researchers from the Icahn School of Medicine at Mount Sinai have discovered that histones are steadily replaced in brain cells throughout life - a process which helps to switch genes on and off.

The research is in Neuron. (full access paywall)

Research: “Critical Role of Histone Turnover in Neuronal Transcription and Plasticity” by Ian Maze, Wendy Wenderski, Kyung-Min Noh, Rosemary C. Bagot, Nikos Tzavaras, Immanuel Purushothaman, Simon J. Elsässer, Yin Guo, Carolina Ionete, Yasmin L. Hurd, Carol A. Tamminga, Tobias Halene, Lorna Farrelly, Alexey A. Soshnev, Duancheng Wen, Shahin Rafii, Marc R. Birtwistle, Schahram Akbarian, Bruce A. Buchholz, Robert D. Blitzer, Eric J. Nestler, Zuo-Fei Yuan, Benjamin A. Garcia, Li Shen, Henrik Molina, and C. David Allis in Neuron doi:10.1016/j.neuron.2015.06.014

Image: Specifically, the study examined a specific type of histone called H3.3 in human and rodent brains. H3.3 is a version of the histone H3 with a small random genetic change in its code, and thus a small difference in its protein structure. Cells with this version of H3.3 frequently turn over their histones. Image is for illustrative purposes only. The original image caption reads: Schematic representation of the nucleosome, the smallest subunit of the chromatin. The DNA (grey) is wrapped around the nucleosomal core proteins, the histones H2A (yellow), H2B (red), H3 (blue), and H4 (green). The nucleosomal linker is the section of the DNA that is not wrapped around the core. It is normally attached to the histone H1 (not shown). The total length of the DNA per nucleosome is ~180 bp. Image credit: Zephyris.

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fMRI studies have found that the brains of those with dyslexia rely more on the right hemisphere and frontal lobe than the brains of those without it. This means, when they read a word, it takes a longer trip through their brain and can get delayed in the frontal lobe. Because of this neurobiological glitch, they read with more difficulty.

But those with dyslexia can physically change their brain and improve their reading with an intensive, multi-sensory intervention that breaks the language down and teaches the reader to decode based on syllable types and spelling rules. The brains of those with dyslexia begin using the left hemisphere more efficiently while reading, and their reading improves.

Learn more about dyslexia by watching the TED-Ed Lesson What is dyslexia? - Kelli Sandman-Hurley

Animation by Marc Cristoforidis

The hard science of oxytocin

Oxytocin has been of keen interest to neuroscientists since the 1970s, when studies started to show that it could drive maternal behaviour and social attachment in various species. Its involvement in a range of social behaviours2, including monogamy in voles, mother–infant bonding in sheep, and even trust between humans, has earned it a reputation as the ‘hug hormone’. “People just concluded it was a bonding molecule, a cuddling hormone, and that’s the pervasive view in the popular press,” says Larry Young, a neuroscientist at Emory University in Atlanta, Georgia, who has been studying the molecule since the 1990s.

That view has led some clinicians to try oxytocin as a treatment for psychiatric conditions such as autism spectrum disorder. But the early trials have had mixed results, and scientists are now seeking a deeper understanding of oxytocin and how it works in the brain. Researchers such as Froemke are showing that the hormone boosts neuronal signals in a way that could accentuate socially relevant input such as distress calls or possibly facial expressions. And clinical researchers are starting a wave of more ambitious trials to test whether oxytocin can help some types of autism. The work is leading to a more sophisticated view of the hormone and its complex effects on behaviour — one that will take many types of expertise to refine.

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(Image caption: An example of TH-positive projections (red) from the inner chamber to the area of the outer chamber after 21 days. Scale bar = 100 mm. GFP (green) indicates neocortical neurons and TH (red) indicates mDA neurons. In the lower picture, each type has been tagged with fluorescent markers so that the locations and types can be identified. The fine tendrils indicate the growth of synapses between the neocortical and mDA neurons, mimicking the structures found in vivo.)

Researchers Develop New Technique for Modeling Neuronal Connectivity Using Stem Cells

Human stem cells can be differentiated to produce other cell types, such as organ cells, skin cells, or brain cells. While organ cells, for example, can function in isolation, brain cells require synapses, or connectors, between cells and between regions of the brain. In a new study published in Restorative Neurology and Neuroscience, researchers report successfully growing multiple brain structures and forming connections between them in vitro, in a single culture vessel, for the first time.

“We have developed a human pluripotent stem cell (hPSC)-based system for producing connections between neurons from two brain regions, the neocortex and midbrain,” explained lead investigator Chun-Ting Lee, PhD, working in the laboratory of William J. Freed, PhD, of the Intramural Research Program, National Institute on Drug Abuse, National Institutes of Health, Baltimore, MD.

Mesencephalic dopaminergic (mDA) neurons and their connections to other neurons in the brain are believed to be related to disorders including drug abuse, schizophrenia, Parkinson’s disease, and perhaps eating disorders, attention deficit-hyperactivity disorder, Tourette’s syndrome, and Lesch-Nyhan syndrome. However, studying mDA neurons and neocortical neurons in isolation does not reveal much data about how these cells actually interact in these conditions. This new capability to grow and interconnect two types of neurons in vitro now provides researchers with an excellent model for further study.

“This method, therefore, has the potential to expand the potential of hPSC-derived neurons to allow for studies of human neural systems and interconnections that have previously not been possible to model in vitro,” commented Dr. Lee.

Using a special container called an “ibidi wound healing dish,” which contains two chambers separated by a removable barrier, the researchers used hPSC to grow mDA neurons and neocortical neurons in the two individual chambers. The barrier was removed after colonies of both types of cells had formed and further growth resulted in the formation of synapses between neurons from each colony.

Future experiments could employ modifications of this method to examine connections between any two brain regions or neuronal subtypes that can be produced from hPSCs in vitro.

Cortisol Reinforces Traumatic Memories

Stress hormone takes effect while people retrieve and reconsolidate emotional memories.

The research is in Neuropsychopharmacology. (full access paywall)

Research: “Effects of Cortisol on Reconsolidation of Reactivated Fear Memories” by Shira Meir Drexler, Christian J Merz, Tanja C Hamacher-Dang, Martin Tegenthoff and Oliver T Wolf in Neuropsychopharmacology doi:10.1038/npp.2015.160

Image: It had been shown that the stress hormone cortisol has a strengthening impact on the consolidation of memories, i.e. the several-hour process in the course of which a memory is formed immediately after the experience. Image is for illustrative purposes only. Image credit: Ben Mills.