by Emily Anthes The overproduction of proteins in brain cells called microglia causes social impairments, cognitive deficits and repetitive behavior in male mice, a new study has found.1 These behavioral differences are not present in female mice, or in mice that produce excess protein in other brain cells, including neurons or star-shaped support cells known as astrocytes. Microglia help eliminate excess synapses — connections between brain cells — that form early in life; this pruning process is crucial to healthy brain development. But male mice that have been engineered to overproduce proteins in these cells have enlarged microglia. That, in turn, lowers the cells’ mobility and may prevent them from migrating to synapses that need eliminating. In support of that idea, the mice have too many synapses, the researchers found — a result that mirrors evidence that certain brain regions may be overconnected in people with autism. “Increased protein synthesis in microglia is sufficient to cause autism phenotypes in mice,” says lead investigator Baoji Xu, professor of neuroscience at the Scripps Research Institute in Jupiter, Florida. “Problems in microglia could be an important pathological mechanism for autism.” Malfunctioning microglia: The researchers studied mice that produce excess levels of EIF4E, a protein that facilitates the synthesis of other proteins. Mutations in several genes linked to autism — including TSC1, TSC2, PTEN and FMR1 — are associated with elevated levels of an active form of EIF4E and, as a result, many other proteins in the brain. Mice that overproduce EIF4E also display autism-like behavior, researchers have previously found. © 2020 Simons Foundation

Keyword: Autism; Glia
Link ID: 27273 - Posted: 06.01.2020

by Marcus A. Banks Brain structures differ in volume depending on a person’s social environment and socioeconomic status, and between men and women, according to a new analysis1. The findings could help explain differences seen in the brains of autistic women and men, many of whom find social communication challenging. Researchers analyzed brain scans from about 10,000 people enrolled in the UK Biobank, a large-scale initiative to understand health trends in the United Kingdom. The participants were 55 years old, on average. They completed surveys, answering questions about their income level, satisfaction with friends and family, participation in social activities and feelings of loneliness. The researchers found that associations between the survey responses and the volume of brain regions linked to social contact differ by sex. For example, women who live with two or more people have a larger amygdala — a brain region involved in decision-making and emotional responses — than do women from smaller households. By contrast, household size has little effect on the size variation of amygdalae among men. The study appeared 18 March in Science Advances. The scans also showed that men who say they lack social support from siblings and friends tend to have a larger nucleus accumbens, part of the brain’s reward circuitry, than men who reported having more social support. The researchers did not see this difference in women. Other differences between men and women appeared in networks involving multiple brain regions, such as those involved with visual processing. © 2020 Simons Foundation

Keyword: Sexual Behavior; Brain imaging
Link ID: 27260 - Posted: 05.21.2020

By Dennis Normile Scientists studying brains and other organs and cancerous tumors have long tried to get detailed 3D views of their insides—down to the level of blood vessel and cell type. But producing such images is time-consuming and difficult. Now, dramatic improvements to a 3D imaging technique can reveal the internal components of entire organs or even animals in a simple procedure, researchers report this week. The new tissue staining protocol allows cellular level analyses in unprecedented detail; it could aid research efforts in neuroscience, developmental and evolutionary biology, and immunology, and it could prove useful in diagnosing some cancers and studying damaged brain tissue after death. To image biological samples in 3D, researchers basically have two main options: They can slice tissues into thin sections and use computer software to reconstruct the whole sample, or they can render biological tissue transparent using special chemicals, which lets researchers view its interior with an optical microscope. To distinguish different cell types, researchers typically stain tissues by soaking them in a cocktail of dyes and chemicals. But getting staining dyes to penetrate organs and large samples has proved difficult. To tackle this problem, researchers at the RIKEN Center for Biosystems Dynamics Research identified a gel that closely mimics the physicochemical properties of organs that have undergone the tissue clearing process. Starting with computer simulations and following up with laboratory tests, the team optimized the soaking solution temperature, dye and antibody concentrations, chemical additives, and electrical properties to produce the best staining and imaging results. They then tested their method with more than two dozen commonly used dyes and antibodies on mouse and marmoset brains. © 2020 American Association for the Advancement of Science.

Keyword: Brain imaging
Link ID: 27227 - Posted: 05.02.2020

By Benjamin Powers On the 10th floor of a nondescript building at Columbia University, test subjects with electrodes attached to their heads watch a driver’s view of a car going down a street through a virtual reality headset. All the while, images of pianos and sailboats pop up to the left and right of each test subject’s field of vision, drawing their attention. The experiment, headed by Paul Sajda, a biomedical engineer and the director of Columbia’s Laboratory for Intelligent Imaging and Neural Computing, monitors the subjects’ brain activity through electroencephalography technology (EEG), while the VR headset tracks their eye movement to see where they’re looking — a setup in which a computer interacts directly with brain waves, called a brain computer interface (BCI). In the Columbia experiment, the goal is to use the information from the brain to train artificial intelligence in self-driving cars, so they can monitor when, or if, drivers are paying attention. BCIs are popping up in a range of fields, from soldiers piloting a swarm of drones at the Defense Advanced Research Projects Agency (DARPA) to a Chinese school monitoring students’ attention. The devices are also used in medicine, including versions that let people who have been paralyzed operate a tablet with their mind or that give epileptic patients advance warning of a seizure. And in July 2019, Elon Musk, the CEO and founder of Tesla and other technology companies, showed off the work of his venture Neuralink, which could implant BCIs in people’s brains to achieve “a symbiosis with artificial intelligence.”

Keyword: Robotics; Brain imaging
Link ID: 27209 - Posted: 04.22.2020

Abby Olena Instead of a traditional lymphatic system, the brain harbors a so-called glymphatic system, a network of tunnels surrounding arteries and veins through which fluid enters and waste products drain from the brain. In a study published March 25 in Science Translational Medicine, researchers show that the rodent eye also has a glymphatic system that takes out the trash through spaces surrounding the veins within the optic nerve. They also found that this system may be compromised in glaucoma and is capable of clearing amyloid-β, the build up of which has been implicated in the development of Alzheimer’s disease, glaucoma, and age-related macular degeneration. The work began in the group of Maiken Nedergaard, a neuroscientist with labs at both the University of Rochester Medical School and the University of Copenhagen, who described the glymphatic system of the brain in 2012. Xiaowei Wang, then a graduate student in Nedergaard’s group and now a postdoc at the University of California, San Francisco, was interested in the eye and spearheaded the search for an ocular glymphatic system. At that point, nobody had speculated that the optic nerve—in addition to transmitting electrical signals—is also a fluid transport highway, Nedergaard says. As Wang’s project was getting underway, Nedergaard met Lu Chen, a neuroscientist at the University of California, Berkeley, at a meeting. Chen’s group had done previous research on ocular lymphatics that focused on the front of the eye. There, the majority of the aqueous humor—the fluid that fills the chamber between the cornea and the lens—drains from the eye to the surrounding vasculature through a circular lymph-like vessel called Schlemm’s canal. This helps regulate intraocular pressure. Chen tells The Scientist that she and Nedergaard decided to collaborate to connect the knowledge about the front of the eye with their questions about the back of the eye. © 1986–2020 The Scientist

Keyword: Brain imaging; Vision
Link ID: 27207 - Posted: 04.22.2020

Gregory Berns, M.D., Ph.D. There is no official census for dogs and cats, but in 2016, the American Veterinary Medical Association estimated that 59 percent of households in the United States had a pet. Although the numbers of dogs and cats remains debatable, dogs continue to gain in popularity with 38 percent of households having at least one. Families with children are even more likely to have a dog (55 percent). With all due respect to cats, dogs have insinuated themselves into human society, forming deep emotional bonds with us and compelling us to feed and shelter them. Worldwide, the dog population is approaching one billion, the majority free-ranging. Even though many people are convinced they know what their dog is thinking, little is actually known about what is going on in dogs’ heads. This may be surprising because the field of experimental psychology had its birth with Pavlov and his salivating dogs. But as dogs gained traction as household pets, in many cases achieving the status of family members, their use as research subjects fell out of favor. In large part, this was a result of the Animal Welfare Act of 1966, which set standards for the treatment of animals in research and put an end to the practice of stealing pets for experimentation. How strange it is then that these creatures, whose nearest relatives are wolves, live with us and even share our beds, yet we know almost nothing about what they’re thinking. In the last decade or so, however, the situation has begun to change, and we are in the midst of a renaissance of canine cognitive science. Research labs have sprung up around the world, and dogs participate not as involuntary subjects, but as partners in scientific discovery. This new research is beginning to shed light on what it’s like to be a dog and the nature of the dog-human bond. © 2020 The Dana Foundation.

Keyword: Brain imaging; Evolution
Link ID: 27195 - Posted: 04.16.2020

Our ability to study networks within the nervous system has been limited by the tools available to observe large volumes of cells at once. An ultra-fast, 3D imaging technique called SCAPE microscopy, developed through the National Institutes of Health (NIH)’s Brain Research through Advancing Innovative Technologies (BRAIN) Initiative, allows a greater volume of tissue to be viewed in a way that is much less damaging to delicate networks of living cells. In a study published in Science, researchers used SCAPE to watch for the first time how the mouse olfactory epithelium — the part of the nervous system that directly perceives smells — reacted in real time to complex odors. They found that those nerve cells may play a larger and more complex role in interpreting smells than was previously understood. “This is an elegant demonstration of the power of BRAIN Initiative technologies to provide new insights into how the brain decodes information to produce sensations, thoughts, and actions,” said Edmund Talley, Ph.D., program director, National Institute of Neurological Disorders and Stroke (NINDS), a part of NIH. The SCAPE microscope was developed in the laboratory of Elizabeth M.C. Hillman, Ph.D., professor of biomedical engineering and radiology and principal investigator at Columbia’s Zuckerman Institute in New York City. “SCAPE microscopy has been incredibly enabling for studies where large volumes need to be observed at once and in real time,” said Dr. Hillman. “Because the cells and tissues can be left intact and visualized at high speeds in three dimensions, we are able to explore many new questions that could not be studied previously.”

Keyword: Brain imaging; Chemical Senses (Smell & Taste)
Link ID: 27189 - Posted: 04.14.2020

by Alla Katsnelson Several regions in the outer layer of the brain are thicker in children and young adults with autism than in their typical peers, a new study finds. The differences are greatest in girls, in children aged 8 to 10 years, and in those with a low intelligence quotient (IQ)1. During typical development, the brain’s outer layer, called the cerebral cortex, thickens until about age 2 and then grows gradually thinner into adolescence as the brain matures. The new study, one of the largest to investigate cortical thickness in autism, aligns with others that indicate this trajectory differs in people with the condition. The findings suggest that brain structure does not change in a uniform way in autism, but instead varies with factors such as age, gender and IQ, says lead researcher Mallar Chakravarty, assistant professor of psychiatry at McGill University in Montreal, Canada. These variations could help explain the inconsistent findings about cortical thickness and autism seen in earlier studies that did not consider such factors, says Christine Wu Nordahl, associate professor of psychiatry and behavioral sciences at the University of California, Davis MIND Institute, who was not involved in the work. “I think this is the type of study we need to be doing as a field, more and more,” she says. The researchers began with unprocessed magnetic resonance imaging (MRI) brain scans of 3,145 participants from previous studies conducted at multiple institutions. © 2020 Simons Foundation

Keyword: Autism; Brain imaging
Link ID: 27188 - Posted: 04.14.2020

By Pragya Agarwal If you have seen the documentary Free Solo, you will be familiar with Alex Honnold. He ascends without protective equipment of any kind in treacherous landscapes where, above about 15 meters, any slip is generally lethal. Even just watching him pressed against the rock with barely any handholds makes me nauseous. In a functional magnetic resonance imaging (fMRI) test with Honnold, neurobiologist Jane Joseph found there was near zero activation in his amygdala. This is a highly unusual brain reaction and may explain why Alex feels no threat in free solo climbs that others wouldn’t dare attempt. But this also shows how our amygdala activates in that split second to warn us, and why it plays an important role in our unconscious biases. Having spent many years researching unconscious bias for my book, I have realized that it remains problematic to pinpoint as it is hidden and is often in complete contrast to what are our expected beliefs. Neuroimaging research is beginning to give us more insight into the formation of our unconscious biases. Recent fMRI neuroscience studies demonstrate that people use different areas of the brain when reasoning about familiar and unfamiliar situations. The neural zones that respond to stereotypes primarily include the amygdala, the prefrontal cortex, the posterior cingulate and the anterior temporal cortex, and that they are described as all “lighting up like a Christmas tree” when stereotypes are activated (certain parts of the brain become more activated than others during certain tasks). People also use different areas of the brain when reasoning about familiar and unfamiliar situations. When we meet someone new, we are not merely focusing on our verbal interaction. © 2020 Scientific American,

Keyword: Attention; Brain imaging
Link ID: 27184 - Posted: 04.13.2020

by Michael Marshall Some people with autism have an unusually large head: This fact has been known since autism was first described in the 1940s. But debate about this finding has raged ever since. How many people with autism have a large head? What causes the enlargement? And does it have any bearing on outcome? Here is what researchers do and do not know about head size in autism. What proportion of people with autism have a large head? When Leo Kanner first described 11 children with autism in a 1943 paper, he noted many unusual features. “Five had relatively large heads,” he reported, and he said no more on the matter. But the sample size was small. Many other scientists noted the same link over the following decades. A 1999 review estimated that 20 percent of people with autism have statistically large head size, or ‘macrocephaly’1. In 2011, the Autism Phenome Project refined this estimate to 15 percent of autistic boys2. The team followed boys with autism from their diagnosis throughout childhood. They focused on whether head size is disproportionate to the rest of the body, rather than simply large. The researchers call this ‘disproportionate megalencephaly’ and say it marks a distinct subgroup of autistic people. “We’ve defined a big-brain form of autism,” says lead investigator David Amaral, distinguished professor of psychiatry and behavioral sciences at the University of California, Davis MIND Institute. No one contests the 15 percent figure, but scientists differ in their interpretation of the finding. “It only applies to a small proportion of children with autism,” says Katarzyna Chawarska, Emily Fraser Beede Professor of Child Psychiatry at Yale University. © 2020 Simons Foundation

Keyword: Autism; Brain imaging
Link ID: 27179 - Posted: 04.10.2020

Kristen Jordan Shamus, Detroit Free Press A 58-year-old woman hospitalized in the Henry Ford Health System who has the new coronavirus developed a rare complication: encephalitis. In a case report published online Tuesday in the journal Radiology, a team of doctors say the woman tested positive for the coronavirus, but also developed a case of acute necrotizing encephalitis, or ANE, a central nervous infection that mostly afflicts young children. It is believed to be the first published case linking COVID-19 and acute necrotizing encephalitis. The rare and serious brain disease can develop in people who have a viral infection, and causes lesions to form in the brain, tissue death and symptoms such as seizures, drowsiness, confusion and coma. The woman, who was identified as an airline worker, had several days of fever, cough and muscle aches, and was taken by ambulance March 19 to a Henry Ford emergency room, said Dr. Elissa Fory, a Henry Ford neurologist. The patient also showed signs of confusion, lethargy and disorientation. A flu test turned up negative but a rapid COVID-19 test, developed in-house by Henry Ford’s clinical microbiology lab, confirmed she had the coronavirus, Fory said. When the woman remained lethargic, doctors ordered repeat CT and MRI scans, which revealed abnormal lesions in both thalami and temporal lobes, parts of the brain that control consciousness, sensation and memory function. These scans confirmed doctors’ early suspicions.

Keyword: Miscellaneous
Link ID: 27160 - Posted: 04.02.2020

By Robert Frederick An early sign of neurodegenerative disease at the cellular level is often the loss of integrity in axons, the threadlike part of neurons that conduct impulses. To find out what causes that loss of integrity, researchers have been trying to better understand the axon’s lining, called the membrane-associated periodic scaffold (MPS). If neuroscientists can discover what signals the MPS to disassemble, they may gain an early diagnostic tool for neurodegenerative diseases or a new target for drug therapy. Back in 2013, researchers using advanced optical microscopy identified the presence of rings in the MPS made from the protein actin. At first, the discovery was met with skepticism because no one had seen the rings using electron microscopes, which have more resolution than optical methods. But preparing neurons for electron microscopy often involves dissolving the membrane with a surfactant. “If you remove completely the membrane, you also disorganize the scaffold that is very tightly associated with the membrane,” says Christophe Leterrier, a neuro-biologist at Aix-Marseille Université in France. To see the periodic rings (shown above in orange at increasing levels of zoom) Leterrier combined optical and electron microscopy. Just as previous researchers had done to visualize the MPS, the first step involved a technique called unroofing a cell, which can isolate a cell’s membrane without disorganizing the underlying scaffold. But the researchers then used electron microscopy to image the same unroofed axon: Teamed up with Stéphane Vassilopoulos, Leterrier’s group essentially made a platinum replica of the MPS and used electron microscopy (shown above in grayscale) on the replica “to really see individual proteins.” The researchers published their findings in Nature Communications, discovering that the rings are like braided wreaths made from long actin filaments. Leterrier says the next step is to find what signal will prompt the MPS to disassemble but will not affect a neuron’s other actin structures, such as dendritic spines, which receive other neurons’ signals. © 2020 Sigma Xi, The Scientific Research Honor Society

Keyword: Brain imaging
Link ID: 27159 - Posted: 04.02.2020

Nicola Davis Reading minds has just come a step closer to reality: scientists have developed artificial intelligence that can turn brain activity into text. While the system currently works on neural patterns detected while someone is speaking aloud, experts say it could eventually aid communication for patients who are unable to speak or type, such as those with locked in syndrome. “We are not there yet but we think this could be the basis of a speech prosthesis,” said Dr Joseph Makin, co-author of the research from the University of California, San Francisco. Writing in the journal Nature Neuroscience, Makin and colleagues reveal how they developed their system by recruiting four participants who had electrode arrays implanted in their brain to monitor epileptic seizures. These participants were asked to read aloud from 50 set sentences multiple times, including “Tina Turner is a pop singer”, and “Those thieves stole 30 jewels”. The team tracked their neural activity while they were speaking. This data was then fed into a machine-learning algorithm, a type of artificial intelligence system that converted the brain activity data for each spoken sentence into a string of numbers. To make sure the numbers related only to aspects of speech, the system compared sounds predicted from small chunks of the brain activity data with actual recorded audio. The string of numbers was then fed into a second part of the system which converted it into a sequence of words. © 2020 Guardian News & Media Limited

Keyword: Language; Brain imaging
Link ID: 27155 - Posted: 03.31.2020

By Stephen Casper. The poet Emily Dickinson rendered the brain wider than the sky, deeper than the sea, and about the weight of God. Scientists facing the daunting task of describing this organ conventionally conjure up different kinds of metaphor — of governance; of maps, infrastructure networks and telecommunications; of machines, robots, computers and the Internet. The comparisons have been practical and abundant. Yet, perhaps because of their ubiquity, the metaphors we use to understand the brain often go unnoticed. We forget that they are descriptors, and see them instead as natural properties. Such hidden dangers are central to biologist and historian Matthew Cobb’s The Idea of the Brain. This ambitious intellectual history follows the changing understanding of the brain from antiquity to the present, mainly in Western thought. Cobb outlines a growing challenge to the usefulness of metaphor in directing and explaining neuroscience research. With refreshing humility, he contends that science is nowhere near working out what brains do and how — or even if anything is like them at all. Cobb shows how ideas about the brain have always been forged from the moral, philosophical and technological frameworks to hand for those crafting the dominant narratives of the time. In the seventeenth century, the French philosopher René Descartes imagined an animal brain acting through hydraulic mechanisms, while maintaining a view of the divine nature of a mind separate from matter. Later authorities, such as the eighteenth-century physician and philosopher Julien Offray de Le Mettrie, secularized the image and compared the human to a machine. The Italian physicist Alessandro Volta rejected the idea of ‘animal electricity’, proposed by his rival Luigi Galvani as a vital force that animates organic matter. Volta was driven at least partly by his aversion to the mechanistic view. © 2020 Springer Nature Limited

Keyword: Brain imaging
Link ID: 27154 - Posted: 03.31.2020

Eric Haseltine A recent bulletin from physicians in the UK described the loss of smell and taste in COVID-19 patients, suggesting that the virus might affect parts of the central nervous system, in addition to its well-known affinity for the respiratory system. Indeed, in an earlier outbreak of coronavirus in China, Hong Kong researcher Dr. K.K. Lau and co-workers found that some patients exhibited convulsions, delirium and restlessness, while Dr. Jun Xu, of the Guangzhou Institute of Respiratory Diseases estimated that 4-5% of all SARS coronavirus patients displayed central nervous system symptoms. Some SARS coronavirus patients have even exhibited marked brain damage on CAT scans. In the latest outbreak of coronavirus, evidence of central nervous system involvement is accumulating, such as a March 21st report by Dr. Asia Filatov of Charles E. Schmidt College of Medicine, that a COVID-19 patient exhibited encephalopathy (brain disease). And recent data from Wuhan, described in the March 12 edition of Neurology Today, indicate that neurological symptoms, such as "altered consciousness," occur in up to one third of COVID-19 cases. But could central nervous system action of COVID-19 directly contribute to the acute respiratory distress associated with the disease? The answer might be “yes” according to recent collaborative research from Drs. Y.C. LI and W.Z. Bai Dr. T. and Hashikawa in Japan. Writing in the Feb 27 edition of the Journal of Medical Virology, Li and colleagues, cite research on coronavirus showing that sometimes SARS-Cov infects brainstem centers that control respiration, making it difficult for infected patients to breathe spontaneously. © 2020 Sussex Publishers, LLC

Keyword: Miscellaneous
Link ID: 27142 - Posted: 03.25.2020

Bob McDonald · CBC Radio Technology used to determine the structure of the Earth's interior using seismic waves has been adapted into a prototype brain scanner that could give results in real time. It could also be cheaper and simpler to use than technologies like MRI or CT scans. For decades, geologists have used sound waves travelling through the Earth, either from earthquakes or artificial sources, to search for oil, image fault lines and attempt to predict earthquakes. Reading reflections and refraction of the waves as they pass through different kinds of rocks and deposits can help geologists essentially do an ultrasound to build up a picture of the Earth. But in recent years seismology has been supercharged by a computational technique called full waveform inversion (FWI), which uses complex computer algorithms to scavenge ever more information from seismic data, and make much more detailed and accurate 3D maps of the Earth's crust. Now scientists at Imperial College London have adapted the same technology into a prototype head-mounted scanner that produced imaging information they say could be used in the future to produce high-resolution 3D images of the brain. The wavefield is shown as it propagates across the head. (Dr Lluís Guasch / Imperial College London / University College London / Nature Digital Medicine) The device uses a helmet fitted with an array of acoustic transducers that act as both sound transmitters and receivers. The system uses low frequency sound waves that are able to penetrate the skull and pass through the brain without harming brain tissue. The sound waves are altered as they pass through different brain structures, then the signals are read and run through the FWI algorithm. In simulations the team got results that make them confident they can produce high-resolution 3D images that may be as good, if not better, than more traditional approaches. ©2020 CBC/Radio-Canada.

Keyword: Brain imaging
Link ID: 27122 - Posted: 03.16.2020

By R. Douglas Fields Our concepts of how the two and a half pounds of flabby flesh between our ears accomplish learning date to Ivan Pavlov’s classic experiments, where he found that dogs could learn to salivate at the sound of a bell. In 1949 psychologist Donald Hebb adapted Pavlov’s “associative learning rule” to explain how brain cells might acquire knowledge. Hebb proposed that when two neurons fire together, sending off impulses simultaneously, the connections between them—the synapses—grow stronger. When this happens, learning has taken place. In the dogs’ case, it would mean the brain now knows that the sound of a bell is followed immediately by the presence of food. This idea gave rise to an oft-quoted axiom: “Synapses that fire together wire together.” The theory proved sound, and the molecular details of how synapses change during learning have been described in detail. But not everything we remember results from reward or punishment, and in fact, most experiences are forgotten. Even when synapses do fire together, they sometimes do not wire together. What we retain depends on our emotional response to an experience, how novel it is, where and when the event occurred, our level of attention and motivation during the event, and we process these thoughts and feelings while asleep. A narrow focus on the synapse has given us a mere stick-figure conception of how learning and the memories it engenders work. It turns out that strengthening a synapse cannot produce a memory on its own, except for the most elementary reflexes in simple circuits. Vast changes throughout the expanse of the brain are necessary to create a coherent memory. Whether you are recalling last night’s conversation with dinner guests or using an acquired skill such as riding a bike, the activity of millions of neurons in many different regions of your brain must become linked to produce a coherent memory that interweaves emotions, sights, sounds, smells, event sequences and other stored experiences. Because learning encompasses so many elements of our experiences, it must incorporate different cellular mechanisms beyond the changes that occur in synapses. This recognition has led to a search for new ways to understand how information is transmitted, processed and stored in the brain to bring about learning. In the past 10 years neuroscientists have come to realize that the iconic “gray matter” that makes up the brain’s outer surface—familiar from graphic illustrations found everywhere, from textbooks to children’s cartoons—is not the only part of the organ involved in the inscription of a permanent record of facts and events for later recall and replay. It turns out that areas below the deeply folded, gray-colored surface also play a pivotal role in learning. © 2020 Scientific American

Keyword: Learning & Memory; Glia
Link ID: 27114 - Posted: 03.12.2020

Ashley Yeager Genes that code for the structure and function of brain regions essential for learning, memory, and decision-making are beginning to be revealed, according to a report published last October in Nature Genetics. Analyzing MRI scans and blood samples from more than 38,000 individuals, as well as gene expression, methylation, and neuropathology of hundreds of postmortem brains, an international team of researchers identified 199 genes that affect the development of the brain, the connections and communication among nerve cells, and susceptibility to neurological disorders. New tools for studying neural tissue, such as RNA sequencing, have spurred a “very strong revival in studying human postmortem brains,” says Sabina Berretta, director of the Harvard Brain Tissue Resource Center at McLean Hospital in Boston. The Nature Genetics study and others like it have the potential to answer many questions about how the healthy brain functions, but they highlight one of the major challenges neuroscientists face right now—limited access to donated brain tissue, specifically from individuals unaffected by neurological disorders. While the Nature Genetics study included massive amounts of data from scans and blood, the researchers had gene expression data from only 508 postmortem brains. “We are really fortunate to get donations from people with a very large variety of dementias and other neurological disorders, such as Parkinson’s and Huntington’s disease,” Berretta says. “But we get very few donations from people that suffer from psychiatric disorders, schizophrenia, bipolar disorder, major depression, and anxiety, and [even fewer from] unaffected donors.” As a result, brain banks are reaching out to religious groups and also scientific communities not tied to any particular neurological condition to increase donations of healthy brains. © 1986–2020 The Scientist.

Keyword: Brain imaging
Link ID: 27075 - Posted: 02.27.2020

Diana Kwon In the 16th century, when the study of human anatomy was still in its infancy, curious onlookers would gather in anatomical theaters to catch of a glimpse of public dissections of the dead. In the years since, scientists have carefully mapped the viscera, bones, muscles, nerves, and many other components of our bodies, such that a human corpse no longer holds that same sense of mystery that used to draw crowds. New discoveries in gross anatomy—the study of bodily structures at the macroscopic level—are now rare, and their significance is often overblown, says Paul Neumann, a professor who specializes in the history of medicine and anatomical nomenclature at Dalhousie University. “The important discoveries about anatomy, I think, are now coming from studies of tissues and cells.” Over the last decade, there have been a handful of discoveries that have helped overturn previous assumptions and revealed new insights into our anatomy. “What’s really interesting and exciting about almost all of the new studies is the illustration of the power of new [microscopy and imaging] technologies to give deeper insight,” says Tom Gillingwater, a professor of anatomy at the University of Edinburgh in the UK. “I would guess that many of these discoveries are the start, rather than the end, of a developing view of the human body.” © 1986–2020 The Scientist

Keyword: Brain imaging
Link ID: 27058 - Posted: 02.20.2020

Nicola Davis Parents should not worry about their teenagers’ delinquent behaviour provided they were well behaved in their earlier childhood, according to researchers behind a study that suggests those who offend throughout their life showed antisocial behaviour from a young age and have a markedly different brain structure as adults. According to figures from the Ministry of Justice, 24% of males in England and Wales aged 10–52 in 2006 had a conviction, compared with 6% of females. Previous work has shown that crime rises in adolescence and young adulthood but that most perpetrators go on to become law-abiding adults, with only a minority – under 10% of the general population – continuing to offend throughout their life. Such trends underpin many modern criminal justice strategies, including in the UK where police can use their discretion as to whether to a young offender should enter the formal justice system. Now researchers say they have found that adults with a long history of offences show striking differences in brain structure compared with those who have stuck to the straight and narrow or who transgressed only as adolescents. “These findings underscore prior research that really highlights that there are different types of young offenders – they are not all the same. They should not all be treated the same,” said Prof Essi Viding, a co-author of the study from University College London. Prof Terrie Moffitt, another co-author of the research from Duke University in North Carolina, said the study helped to shed light on what may be behind persistent antisocial behaviour. © 2020 Guardian News & Media Limited

Keyword: Aggression; Brain imaging
Link ID: 27048 - Posted: 02.18.2020