Neuroscience

Memories More Accessible After a Good Night’s Sleep

Sleeping not only protects memories from being forgotten, it also makes them easier to access, according to new research from the University of Exeter and the Basque Centre for Cognition, Brain and Language. The findings suggest that after sleep we are more likely to recall facts which we could not remember while still awake.

The research will appear in Cortex.

Image: The researcher found that, compared to daytime wakefulness, sleep helped rescue unrecalled memories more than it prevented memory loss. Image is for illustrative purposes only.

Neuroscientists establish brain-to-brain networks in primates, rodents

Neuroscientists at Duke University have introduced a new paradigm for brain-machine interfaces that investigates the physiological properties and adaptability of brain circuits, and how the brains of two or more animals can work together to complete simple tasks.

These brain networks, or Brainets, are described in two articles published in the July 9, 2015, issue of Scientific Reports (1, 2). In separate experiments reported in the journal, the brains of monkeys and the brains of rats are linked, allowing the animals to exchange sensory and motor information in real time to control movement or complete computations.

In one example, scientists linked the brains of rhesus macaque monkeys, who worked together to control the movements of the arm of a virtual avatar on a digital display in front of them. Each animal controlled two of three dimensions of movement for the same arm as they guided it together to touch a moving target.

In the rodent experiment, scientists networked the brains of four rats complete simple computational tasks involving pattern recognition, storage and retrieval of sensory information, and even weather forecasting.

Brain-machine interfaces (BMIs) are computational systems that allow subjects to use their brain signals to directly control the movements of artificial devices, such as robotic arms, exoskeletons or virtual avatars.

The Duke researchers, working at the Center for Neuroengineering, have previously built BMIs to capture and transmit the brain signals of individual rats, monkeys, and even human subjects to artificial devices.

“This is the first demonstration of a shared brain-machine interface, a paradigm that has been translated successfully over the past decades from studies in animals all the way to clinical applications,” said Miguel Nicolelis, M.D., Ph. D., co-director of the Center for Neuroengineering at the Duke University School of Medicine and principal investigator for the study. “We foresee that shared BMIs will follow the same track, and could soon be translated to clinical practice.”

To complete the experiments, Nicolelis and his team outfitted the animals with arrays implanted in their motor and somatosensory cortices to capture and transmit their brain activity.

For one experiment highlighted in the primate article, researchers recorded the electrical activity of more than 700 neurons from the brains of three monkeys as they moved a virtual arm toward a target. In this experiment, each monkey mentally controlled two out of three dimensions (i.e., x-axis and y-axis; see video) of the virtual arm.

The monkeys could be successful only when at least two of them synchronized their brains to produce continuous 3-D signals that moved the virtual arm. As the animals gained more experience and training in the motor task, researchers found that they adapted to the challenge.

The study described in the second paper used groups of three or four rats whose brains were interconnected via microwire arrays in the somatosensory cortex of the brain and received and transmitted information via those wires.

In one experiment, rats received temperature and barometric pressure information and were able to combine information with the other rats to predict an increased or decreased chance of rain. Under some conditions, the authors observed that the rat Brainet could perform at the same level or better than one rat on its own.

These results support the original claim of the same group that Brainets may serve as test beds for the development of organic computers created by the interfacing of multiple animal brains with computers.

Nicolelis and colleagues of the Walk Again Project, based in the project’s laboratory in Brazil, are currently working on a non-invasive human Brainet to be used for neuro-rehabilitation training in paralyzed patients.

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The Most Extreme - Horrors

Some animals are the embodiments of our deepest, darkest fears. Even a glimpse of one will send us running, but why? Scientists have proven that some animals are not as dangerous as we believe, so why are they so scary?

By: XiveTV Documentaries.

Interesting Papers for Week 31, 2015

Human short-term spatial memory: precision predicts capacity. Banta Lavenex, P., Boujon, V., Ndarugendamwo, A., & Lavenex, P. (2015). Cognitive Psychology, 77, 1–19.

Effector mass and trajectory optimization in the online regulation of goal-directed movement. Burkitt, J. J., Staite, V., Yeung, A., Elliott, D., & Lyons, J. L. (2015). Experimental Brain Research, 233(4), 1097–107.

Experimental tests of hypotheses for microsaccade generation. Ghasia, F. F., & Shaikh, A. G. (2015). Experimental Brain Research, 233(4), 1089–95.

The long and winding road to uncertainty: the link between spatial distance and feelings of uncertainty. Glaser, T., Lewandowski, J., & Düsing, J. (2015). PLoS ONE, 10(3), e0119108.

Sweet taste and nutrient value subdivide rewarding dopaminergic neurons in Drosophila. Huetteroth, W., Perisse, E., Lin, S., Klappenbach, M., Burke, C., & Waddell, S. (2015). Current Biology, 25(6), 751–8.

Feature integration in the mapping of multi-attribute visual stimuli to responses. Ishizaki, T., Morita, H., & Morita, M. (2015). Scientific Reports, 5, 9056.

Do the right thing: the assumption of optimality in lay decision theory and causal judgment. Johnson, S. G. B., & Rips, L. J. (2015). Cognitive Psychology, 77, 42–76.

Impaired visuomotor adaptation in adults with ADHD. Kurdziel, L. B. F., Dempsey, K., Zahara, M., Valera, E., & Spencer, R. M. C. (2015). Experimental Brain Research, 233(4), 1145–53.

Spatiotemporal Neural Pattern Similarity Supports Episodic Memory. Lu, Y., Wang, C., Chen, C., & Xue, G. (2015). Current Biology, 25(6), 780–785.

Learning-related brain hemispheric dominance in sleeping songbirds. Moorman, S., Gobes, S. M. H., van de Kamp, F. C., Zandbergen, M. A., & Bolhuis, J. J. (2015). Scientific Reports, 5, 9041.

Effects of aging and idiopathic Parkinson’s disease on tactile temporal order judgment. Nishikawa, N., Shimo, Y., Wada, M., Hattori, N., & Kitazawa, S. (2015). PLoS ONE, 10(3), e0118331.

Navigational path integration by cortical neurons: origins in higher-order direction selectivity. Page, W. K., Sato, N., Froehler, M. T., Vaughn, W., & Duffy, C. J. (2015). Journal of Neurophysiology, 113(6), 1896–906.

Deconstructing multi-sensory enhancement in detection. Pannunzi, M., Pérez-Bellido, A., Pereda-Baños, A., López-Moliner, J., Deco, G., & Soto-Faraco, S. (2014). Journal of Neurophysiology, 113(6).

Functional properties of GABA synaptic inputs onto GABA neurons in monkey prefrontal cortex. Rotaru, D. C., Olezene, C., Miyamae, T., Povysheva, N. V, Zaitsev, A. V, Lewis, D. A., & Gonzalez-Burgos, G. (2015). Journal of Neurophysiology, 113(6), 1850–61.

Ocular dominance plasticity disrupts binocular inhibition-excitation matching in visual cortex. Saiepour, M. H., Rajendran, R., Omrani, A., Ma, W.-P., Tao, H. W., Heimel, J. A., & Levelt, C. N. (2015). Current Biology, 25(6), 713–21.

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The California brown sea hare has a very edgy sex life. But it’s prized by scientists for its gigantic neurons. 

Learn more about these kinky sea slugs in this week’s video—and subscribe!

Eat For Pleasure Rather Than Hunger? You May Have a Hormone Deficiency

New Rutgers study finds absence of peptide linked to preference for fatty food and eating for pleasure rather than hunger.

The research is in Cell Reports. (full open access)

Research: “Endogenous Glucagon-like Peptide-1 Suppresses High-Fat Food Intake by Reducing Synaptic Drive onto Mesolimbic Dopamine Neurons” by Xue-Feng Wang, Jing-Jing Liu, Julia Xia, Ji Liu, Vincent Mirabella, and Zhiping P. Pang in Cell Reports doi:10.1016/j.celrep.2015.06.062

Image: GLP-1 peptides are small sequences of amino acids that have many functions, including how our bodies regulate eating behaviors. They are secreted from cells in both the small intestine and the brain and are supposed to let our brain know when we are satisfied and should put down the fork. Image is for illustrative purposes only.

(Image caption: Activation of auditory cortex during stimulation of the ear by low-frequency sound and infrasound. Credit: Max Planck Institut für Bildungsforschung) 

Can you actually hear “inaudible” sound?

Are wind farms harmful to humans? Some believe so, others refute this; this controversial topic makes emotions run high. To give the debate more objectivity, an international team of experts dealt with the fundamentals of hearing in the lower limit range of the audible frequency range (i.e. infrasound), but also in the upper limit range (i.e. ultrasound). The project, which is part of the European Metrology Research Programme (EMRP), was coordinated by the Physikalisch-Technische Bundesanstalt (PTB). At PTB, not only acoustics experts, but also experts from the fields of biomagnetism (MEG) and functional magnetic resonance imaging (fMRI) were involved in the research activities. They have found out that humans can hear sounds lower than had previously been assumed. And the mechanisms of sound perception are much more complex than previously thought. Another vast field of research opens up here in which psychology also has to be taken into account. And there is definitely a need for further research.

If there is a plan to erect a wind turbine in front of someone’s property, many an eager supporter of the “energy transition” quickly turns into a wind energy opponent. Fear soon starts spreading: the infrasound generated by the rotor blades and by the wind flow might make someone ill. Many people living in the vicinity of such wind farms do indeed experience sleep disturbances, a decline in performance, and other negative effects. Infrasound designates very low sounds, below the limit of hearing, which is around 16 hertz. The wind energy sector and the authorities tend to declare that the sounds generated are inaudible and much too weak to be the source of health problems.

Christian Koch knows for sure, “Neither scaremongering nor refuting everything is of any help in this situation. Instead, we must try to find out more about how sounds in the limit range of hearing are perceived.” This expert in acoustics from PTB is the manager of the international project in which metrology experts from several metrology institutes and scientists from the Max Planck Institute for Human Development in Berlin investigated the fundamentals of the hearing of “inaudible” sounds for 3 years. Very low sounds (i.e. infrasound, below approx. 16 hertz) or very high sounds (i.e. ultrasound, above approx. 16 000 hertz) occur in numerous situations of daily life: infrasound is not only produced by wind turbines, but also sometimes when a truck thunders past a house, or when a home owner installs a power generator in his basement. Ultrasound can, for example, originate from commercial ultrasonic cleaning baths that are sometimes used, e.g., to thoroughly clean a pair of glasses. It can also be generated by a device used as a deterrent against martens (to keep them from gnawing on the wiring of cars). A particular variant of such devices has been developed to keep young people away from certain places – an internationally controversial topic from an ethical viewpoint. These devices, which produce very high-pitched sounds that can only be heard by children and young people, are sometimes used by adults who want to enjoy some peace and quiet. “In all these areas, we have to deal with considerable levels of loudness in some cases,” Christian Koch adds.

An audible loud sound may damage hearing – as well as getting on your nerves. But what exactly is an “audible” sound? And what does a human being really hear? In order to find out more, an infrasonic source which is able to generate sounds that are completely free from harmonics (which is not as trivial as it may sound!) was constructed within the scope of this project. Test persons were asked about their subjective hearing experience, and these (also quantitative) statements were then compared by means of imaging procedures, namely by magnetoencephalography (MEG) and functional magnetic resonance imaging (fMRI). The results have shown that humans hear lower sounds – namely from 8 hertz on – which, after all, is a whole octave than had previously been assumed: an excitation of the primary auditory cortex could be detected down to this frequency. All persons concerned explicitly stated that they had heard something – whereby this perception had not always been tonal. In addition, the observations showed a reaction in certain parts of the brain which play a role in emotions. “This means that a human being has a rather diffuse perception, saying that something is there and that this might involve danger,” Christian Koch says. “But we’re actually at the very beginning of our investigations. Further research is urgently needed.” An application for a follow-up project has already been filed. In this project, the investigations will be focused on the question why some persons feel disturbed by “inaudible” sound, whereas others are not even bothered: many a home owner is left cold by having a wind turbine next to their homes. And we need to take another effect into account: namely, that some people become really ill because they imagine risks which, in reality, might not even exist. This is the reason why it makes sense to involve psychologists as well.

But the researchers see a great need for further research also in the other extreme – the ultrasound. Although the measuring instruments used are among the most precise in the world, the researchers were not able to measure whether humans can hear above the previously assumed upper threshold of hearing, and if they can, what they then perceive. Since, however, what applies to other ranges, also applies to high-pitched sounds – namely that a very loud sound may damage the hearing – here too, there is a need for further research.

The results of the international research project might lead to the introduction of uniform – and binding – protection provisions for these limit ranges of hearing within Europe, since there have been none to date.

The same parts of the brain that control the stress response … play an important role in susceptibility and resistance to inflammatory diseases such as arthritis. And since it is these parts of the brain that also play a role in depression, we can begin to understand why it is that many patients with inflammatory diseases may also experience depression at different times in their lives… Rather than seeing the psyche as the source of such illnesses, we are discovering that while feelings don’t directly cause or cure disease, the biological mechanisms underlying them may cause or contribute to disease. Thus, many of the nerve pathways and molecules underlying both psychological responses and inflammatory disease are the same, making predisposition to one set of illnesses likely to go along with predisposition to the other. The questions need to be rephrased, therefore, to ask which of the many components that work together to create emotions also affect that other constellation of biological events, immune responses, which come together to fight or to cause disease. Rather than asking if depressing thoughts can cause an illness of the body, we need to ask what the molecules and nerve pathways are that cause depressing thoughts. And then we need to ask whether these affect the cells and molecules that cause disease.

[…]

We are even beginning to sort out how emotional memories reach the parts of the brain that control the hormonal stress response, and how such emotions can ultimately affect the workings of the immune system and thus affect illnesses as disparate as arthritis and cancer. We are also beginning to piece together how signals from the immune system can affect the brain and the emotional and physical responses it controls: the molecular basis of feeling sick. In all this, the boundaries between mind and body are beginning to blur.

—  Dr. Esther Sterberg, The Balance Within: The Science Connecting Health and Emotions
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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.

Empathy Is Actually A Choice

Psychopaths and narcissists are able to feel empathy; it’s just that they don’t typically want to.

ONE death is a tragedy. One million is a statistic.

You’ve probably heard this saying before. It is thought to capture an unfortunate truth about empathy: While a single crying child or injured puppy tugs at our heartstrings, large numbers of suffering people, as in epidemics, earthquakes and genocides, do not inspire a comparable reaction.

Studies have repeatedly confirmed this. It’s a troubling finding because, as recent research has demonstrated, many of us believe that if more lives are at stake, we will — and should — feel more empathy (i.e., vicariously share others’ experiences) and do more to help.

Not only does empathy seem to fail when it is needed most, but it also appears to play favorites. Recent studies have shown that our empathy is dampened or constrained when it comes to people of different races, nationalities or creeds. These results suggest that empathy is a limited resource, like a fossil fuel, which we cannot extend indefinitely or to everyone.

What, then, is the relationship between empathy and morality? Traditionally, empathy has been seen as a force for moral good, motivating virtuous deeds. Yet a growing chorus of critics, inspired by findings like those above, depict empathy as a source of moral failure. In the words of the psychologist Paul Bloom, empathy is a “parochial, narrow-minded” emotion — one that “will have to yield to reason if humanity is to survive.”

We disagree.

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Sarcasm Has Creative Benefits When People Trust One Another

Research uncovers creative benefits — yes, benefits — in using sarcasm when people trust each other.

The research is in Organizational Behavior and Human Decision Processes. (full access paywall)

Research: “The highest form of intelligence: Sarcasm increases creativity for both expressers and recipients” by Li Huang, Francesca Gino, and Adam D. Galinsky in Organizational Behavior and Human Decision Processes doi:10.1016/j.obhdp.2015.07.001

Image: Actor Bill Murray’s sarcastic style of humor has made him a favorite subject of Internet memes. New research from Harvard Business School’s Francesca Gino and colleagues finds that sarcasm can boost creativity in those dishing it out and in those on its receiving end. Image credit: MemeCrunch/Harvard.

Researchers Identify Critical Genes Responsible for Brain Tumor Growth

After generating new brain tumor models, Cedars-Sinai scientists in the Board of Governors Regenerative Medicine Institute identified the role of a family of genes underlying tumor growth in a wide spectrum of high grade brain tumors.

“With these new genetic findings, our group of researchers plan to develop targeted therapeutics that we hope will one day be used treat patients with high grade brain tumors and increase their survival,” said Joshua Breunig, PhD, a research scientist in the Brain Program at the Cedars-Sinai Board of Governors Regenerative Medicine Institute and lead author of the research study published in the journal Cell Reports.

High grade brain tumors, known as gliomas, are difficult to treat with only a single digit five-year survival rate. Most patients treated for primary gliomas develop into secondary gliomas, which are almost always fatal.

“Any given tumor can harbor a variety of different combinations of mutations,” said Moise Danielpour, MD, Vera and Paul Guerin Family Chair in Pediatric Neurosurgery, director of the Pediatric Neurosurgery Program and the Center for Pediatric Neurosciences in the Maxine Dunitz Children’s Health Center and last author on the study. “Despite advances in radiation and chemotherapy, there are currently no effective curative regimens for treatment for these diverse tumors.”

Researchers first modeled high grade brain tumors from resident stem cells inside the brain, using a cutting edge method of rapid modeling that can create up to five distinct tumor models within 45 minutes.

After effectively modeling high grade brain tumors, researchers identified the Ets family of genes as contributors to glioma brain tumors. These Ets factors function to regulate the behavior of tumor cells by controlling expression of genes necessary for tumor growth and cell fate. When expression of the Ets genes is blocked, researchers can identify and strategize novel treatment therapies.

“The ability to rapidly model unique combinations of driver mutations from a patient’s tumor enhances our quest to create patient-specific animal models of human brain tumors,” added Danielpour.

Immediate next steps involve testing the function of each individual Ets factor to determine their specific role in tumor progression and recurrence after treatment.

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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

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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smithsonianmag.com
Tibetan monk produces brain gamma waves never before reported in neuroscience
By Rachel Nuwer

By Rachel Nuwer

Matthieu Ricard, a 66-year old Tibetan monk and geneticist, produces brain gamma waves—linked to consciousness, attention, learning and memory—never before reported in neuroscience, leading researchers to conclude that Ricard is the world’s happiest man. The secret to his success in achieving bliss? Meditation, he claims.

Meditating is like lifting weights or exercising for the mind, Ricard told the Daily News. Anyone can be happy by simply training their brain, he says.

To quantify just how happy Ricard is, neuroscientists at the University of Wisconsin attached 256 sensors to the monk’s skull. When he meditated on compassion, the researchers were shocked to see that Ricard’s brian produces a level of gamma waves off the charts. He also demonstrated excessive activity in his brain’s left prefrontal cortex compared to its right counterpart, meaning he has an abnormally large capacity for happiness and a reduced propensity towards negativity, the researchers say.

During the same study, the neuroscientists also peeked into the minds of other monks. They found that long-term practitioners—those who have engaged in more than 50,000 rounds of meditation—showed significant changes in their brain function, although that those with only three weeks of 20-minute meditation per day also demonstrated some change.

To spread the word on achieving happiness and enlightenment, Ricard authored Happiness: A Guide to Developing Life’s Most Important Skill. Proceeds from the book go towards over 100 humanitarian projects.

“Try sincerely to check, to investigate,” he explained to the Daily News. “That’s what Buddhism has been trying to unravel — the mechanism of happiness and suffering. It is a science of the mind.”

Why Smart People Tend to Live Longer

The tendency of more intelligent people to live longer has been shown, for the first time, to be mainly down to their genes.

The research is in International Journal of Epidemiology. (full open access)

Research: “The association between intelligence and lifespan is mostly genetic” by Rosalind Arden, Michelle Luciano, Ian J Deary, Chandra A Reynolds, Nancy L Pedersen, Brenda L Plassman, Matt McGue, Kaare Christensen and Peter M Visscher in International Journal of Epidemiology doi:10.1093/ije/dyv112

Image: Studies that compare genetically identical twins with fraternal twins –  who only share half of their twin’s DNA –   help distinguish the effects of genes from the effects of shared environmental factors such as housing, schooling and childhood nutrition. Image is for illustrative purposes only.

(Image caption: Mature hair cells, left, lose connections to outgoing neurons (blue) and gain connections to incoming neurons (red) as they age, right. Credit: Paul Fuchs, Johns Hopkins Medicine)

Found: A Likely New Contributor to Age-Related Hearing Loss

Conventional wisdom has long blamed age-related hearing loss almost entirely on the death of sensory hair cells in the inner ear, but research from neuroscientists at Johns Hopkins has provided new information about the workings of nerve cells that suggests otherwise.

In a paper published July 1 in The Journal of Neuroscience, the Johns Hopkins team says its studies in mice have verified an increased number of connections between certain sensory cells and nerve cells in the inner ear of aging mice. Because these connections normally tamp down hearing when an animal is exposed to loud sound, the scientists think these new connections could also be contributing to age-related hearing loss in the mice, and possibly in humans.

“The nerve cells that connect to the sensory cells of the inner ear are known to inhibit hearing, and although it’s not yet clear whether that’s their function in older mice, it’s quite likely,” says Paul Fuchs, Ph.D., the John E. Bordley Professor of Otolaryngology–Head and Neck Surgery at the Johns Hopkins University School of Medicine. “If confirmed, our findings give us new ideas for how physicians may someday treat or prevent age-related hearing loss.”

Fuchs says the new research builds on the knowledge that inside the ear lies a coiled row of sensory cells responsible for converting sound waves into electrical signals sent through nerve cells to the brain, which processes and tells animals what they “hear.” Two sets of these so-called hair cells — named for the filaments that act like antennae picking up sound waves — exist, an inner tier closest to the brain and an outer tier. The outer ones have a secondary function: to amplify the sound waves within the inner ear. Not surprisingly, Fuchs notes, a loss of outer hair cells closely correlates with a loss of hearing.

But studies over the last decade have suggested that changes over time also occur in the connections between hair cells and the nerve cells to which they are attached.

Each of those nerve cells is like a one-way street, Fuchs says, taking signals either from the ear to the brain or vice versa. The nerve cells that take signals to the ear are known to turn down the amplification provided by outer hair cells when an animal is, for example, exposed to a noisy environment for an extended period of time.

Previous research has suggested that with age, inner hair cells in mice and humans experience a decrease in outgoing nerve cell connections, while incoming nerve cell connections increase.

To find out if the new connections worked — or worked normally — Stephen Zachary, a graduate student in Fuchs’ laboratory, painstakingly recorded electrical signals from within the inner hair cells of young and old mice.

He found that the incoming nerve cells were indeed active and that their activity levels correlated with the animals’ hearing abilities: The harder of hearing an animal was, the higher the activity of its incoming nerve cells.

“These nerve cell connections seem to be reverting back to the way they worked during early development before the animals’ sense of hearing was operating,” says Fuchs. “We don’t know why the new connections form, but it might be as simple as a lack of competition for space once the outgoing nerve cells have retracted.”

If the same phenomenon is occurring in human ears, Fuchs and his team say there may be ways of preventing the incoming nerve cells from forming new connections with inner hair cells, a technique that could help maintain normal hearing through old age.

Was that text hard to read? 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.

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

Animation by Marc Cristoforidis