Links for Keyword: Brain imaging

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By Karen Weintraub Stroke, amyotrophic lateral sclerosis and other medical conditions can rob people of their ability to speak. Their communication is limited to the speed at which they can move a cursor with their eyes (just eight to 10 words per minute), in contrast with the natural spoken pace of 120 to 150 words per minute. Now, although still a long way from restoring natural speech, researchers at the University of California, San Francisco, have generated intelligible sentences from the thoughts of people without speech difficulties. The work provides a proof of principle that it should one day be possible to turn imagined words into understandable, real-time speech circumventing the vocal machinery, Edward Chang, a neurosurgeon at U.C.S.F. and co-author of the study published Wednesday in Nature, said Tuesday in a news conference. “Very few of us have any real idea of what’s going on in our mouth when we speak,” he said. “The brain translates those thoughts of what you want to say into movements of the vocal tract, and that’s what we want to decode.” But Chang cautions that the technology, which has only been tested on people with typical speech, might be much harder to make work in those who cannot speak—and particularly in people who have never been able to speak because of a movement disorder such as cerebral palsy. Chang also emphasized that his approach cannot be used to read someone’s mind—only to translate words the person wants to say into audible sounds. “Other researchers have tried to look at whether or not it’s actually possible to decode essentially just thoughts alone,” he says.* “It turns out it’s a very difficult and challenging problem. That’s only one reason of many that we focus on what people are trying to say.” © 2019 Scientific American

Related chapters from BN8e: Chapter 19: Language and Lateralization; Chapter 2: Functional Neuroanatomy: The Nervous System and Behavior
Related chapters from MM:Chapter 15: Brain Asymmetry, Spatial Cognition, and Language; Chapter 2: Cells and Structures: The Anatomy of the Nervous System
Link ID: 26170 - Posted: 04.24.2019

By Kelly Servick The machines that scan our brains are usually monstrous contraptions, locked away in high-end research centers. But smaller, cheaper technologies may soon enter the field, like an MRI scanner built for the battlefield and a lightweight, wearable magnetoencephalography system that records magnetic fields generated by the brains of people in motion. If such devices become widespread, they’ll raise new ethical questions, says Francis Shen, a law professor and neuroethicist at the University of Minnesota (UMN) in Minneapolis and Massachusetts General Hospital in Boston. How should researchers share results with the far-flung populations they may soon be able to study? Could direct-to-consumer neuroimaging become an industry alongside personal genetic testing? With a grant from the federal Brain Research through Advancing Innovative Neurotechnologies (BRAIN) Initiative, Shen has teamed up with three UMN colleagues, including MRI physicist Michael Garwood, to start a conversation about the ethical implications of portable neuroimaging. Garwood is part of a multicenter team building an MRI machine powerful enough to be used in medical diagnostic tests that weighs just 400 kilograms—less than a tenth of traditional scanners. He expects the new scanner to take its first images in 3 years. And if market demand can bring down the cost of a key component, he thinks it could eventually cost $200,000 or less, versus millions of dollars for current scanners. Shen and Garwood discussed the ethical issues at play with Science, after presenting their work at a meeting of BRAIN Initiative investigators last week in Washington, D.C. This interview has been edited for brevity and clarity. © 2019 American Association for the Advancement of Science

Related chapters from BN8e: Chapter 2: Functional Neuroanatomy: The Nervous System and Behavior
Related chapters from MM:Chapter 2: Cells and Structures: The Anatomy of the Nervous System
Link ID: 26149 - Posted: 04.17.2019

By Kelly Servick At age 16, Danielle Bassett spent most of her day at the piano, trying to train her fingers and ignoring a throbbing pain in her forearms. She hoped to pursue a career in music and had been assigning herself relentless practice sessions. But the more she rehearsed Johannes Brahms's feverish Rhapsody in B Minor on her family's Steinway, the clearer it became that something was wrong. Finally, a surgeon confirmed it: Stress fractures would force her to give up the instrument for a year. "What was left in my life was rather bleak," Bassett says. Her home-schooled upbringing in rural central Pennsylvania had instilled a love of math, science, and the arts. But by 17, discouraged by her parents from attending college and disheartened at her loss of skill while away from the keys, she expected that responsibilities as a housewife and mother would soon eclipse any hopes of a career. "I wasn't happy with that plan," she says. Instead, Bassett catapulted herself into a life of research in a largely uncharted scientific field now known as network neuroscience. A Ph.D. physicist and a MacArthur fellow by age 32, she has pioneered the use of concepts from physics and math to describe the dynamic connections in the human brain. "She's now the doyenne of network science," says theoretical neuroscientist Karl Friston of University College London. "She came from a formal physics background but was … confronted with some of the deepest questions in neuroscience." © 2019 American Association for the Advancement of Science.

Related chapters from BN8e: Chapter 2: Functional Neuroanatomy: The Nervous System and Behavior; Chapter 7: Life-Span Development of the Brain and Behavior
Related chapters from MM:Chapter 2: Cells and Structures: The Anatomy of the Nervous System; Chapter 13: Memory, Learning, and Development
Link ID: 26133 - Posted: 04.12.2019

By Lydia Denworth The vast majority of neuroscientific studies contain three elements: a person, a cognitive task and a high-tech machine capable of seeing inside the brain. That simple recipe can produce powerful science. Such studies now routinely yield images that a neuroscientist used to only dream about. They allow researchers to delineate the complex neural machinery that makes sense of sights and sounds, processes language and derives meaning from experience. But something has been largely missing from these studies: other people. We humans are innately social, yet even social neuroscience, a field explicitly created to explore the neurobiology of human interaction, has not been as social as you would think. Just one example: no one has yet captured the rich complexity of two people’s brain activity as they talk together. “We spend our lives having conversation with each other and forging these bonds,” neuroscientist Thalia Wheatley of Dartmouth College says. “[Yet] we have very little understanding of how it is people actually connect. We know almost nothing about how minds couple.” That is beginning to change. A growing cadre of neuroscientists is using sophisticated technology—and some very complicated math—to capture what happens in one brain, two brains, or even 12 or 15 at a time when their owners are engaged in eye contact, storytelling, joint attention focused on a topic or object, or any other activity that requires social give and take. Although the field of interactive social neuroscience is in its infancy, the hope remains that identifying the neural underpinnings of real social exchange will change our basic understanding of communication and ultimately improve education or inform treatment of the many psychiatric disorders that involve social impairments. © 2019 Scientific American

Related chapters from BN8e: Chapter 2: Functional Neuroanatomy: The Nervous System and Behavior; Chapter 19: Language and Lateralization
Related chapters from MM:Chapter 2: Cells and Structures: The Anatomy of the Nervous System; Chapter 15: Brain Asymmetry, Spatial Cognition, and Language
Link ID: 26128 - Posted: 04.11.2019

By Emily Mullin About noon most days, the Lieber Institute for Brain Development in East Baltimore gets a case — that is, a brain. It arrives in an inconspicuous red cooler. Almost immediately, resident neuropathologist Rahul Bharadwaj gets to work, carefully inspecting it for any abnormalities, such as tumors or lesions. Often, the brains come from the Maryland Medical Examiner’s Office, just a 15-minute drive across town. On other days, they are flown in — packed on dry ice — from around the country. Since opening in 2011, the institute has amassed more than 3,000 of these post-mortem brains that they are studying to better understand the biological mechanisms behind such neuropsychiatric disorders as schizophrenia, major depression, substance abuse, bipolar disorder and post-traumatic stress disorder. About 100 brain banks exist across the country for all sorts of brain diseases. But Lieber, founded with the support and funding of a wealthy couple whose daughter suffered a psychotic break in her 20s, is the biggest collection dedicated specifically to mental conditions. Current therapies for neuropsychiatric disorders — antipsychotics and antidepressants — treat symptoms rather than the underlying cause of illness, which remains largely unknown. And while they can be lifesaving for certain people, they can cause unpleasant and sometimes serious side effects. In some cases, they won't work at all. Most of these drugs were also discovered by accident. Lieber’s goal is to unravel what happens biologically in the brain to make these conditions occur and then to develop therapies to treat these conditions at their root cause, or even prevent them from happening in the first place. © 1996-2019 The Washington Post

Related chapters from BN8e: Chapter 2: Functional Neuroanatomy: The Nervous System and Behavior; Chapter 16: Psychopathology: Biological Basis of Behavior Disorders
Related chapters from MM:Chapter 2: Cells and Structures: The Anatomy of the Nervous System; Chapter 12: Psychopathology: The Biology of Behavioral Disorders
Link ID: 26121 - Posted: 04.08.2019

Corey Hill Allen and Eyal Aharoni Brain evidence is playing an increasing role in criminal trials in the United States. An analysis indicates that brain evidence such as MRI or CAT scans – meant to provide proof of abnormalities, brain damage or disorder in defendants – was used for leniency in approximately 5 percent of murder cases at the appellate level. This number jumps to an astounding 25 percent in death penalty trials. In these cases, the evidence is meant to show that the defendant lacked the capacity to control his action. In essence, “My brain made me do it.” But does evidence of neurobiological disorder or abnormality tend to help or hurt the defendant? Legal theorists have previously portrayed physical evidence of brain dysfunction as a double-edged sword. On the one hand, it might decrease a judge’s or juror’s desire to punish by minimizing the offender’s perceived responsibility for his transgressions. The thinking would be that the crime resulted from disordered brain activity, not any choice on the part of the offender. On the other hand, brain evidence could increase punitive motivations toward the offender by making him seem more dangerous. That is, if the offender’s brain truly “made him” commit the crime, there is an increased risk such behavior could occur again, even multiple times, in the future. To tease apart these conflicting motivations, our team of cognitive neuroscientists, a medical bioethicist and a philosopher investigated how people tend to weigh neurobiological evidence when deciding on criminal sentences. © 2010–2019, The Conversation US, Inc.

Related chapters from BN8e: Chapter 2: Functional Neuroanatomy: The Nervous System and Behavior; Chapter 18: Attention and Higher Cognition
Related chapters from MM:Chapter 2: Cells and Structures: The Anatomy of the Nervous System; Chapter 14: Attention and Consciousness
Link ID: 26111 - Posted: 04.03.2019

By Adrian Cho BOSTON—MRI scanners can map a person's innards in exquisite detail, but they say little about composition. Now, physicists are pushing MRI to a new realm of sensitivity to trace specific biomolecules in tissues, a capability that could aid in diagnosing Alzheimer's and other diseases. The advance springs not from improved scanners, but from better methods to solve a notoriously difficult math problem and extract information already latent in MRI data. The new techniques, described this month at a meeting of the American Physical Society here, could soon make the jump to the clinic, says Shannon Kolind, a physicist at the University of British Columbia (UBC) in Vancouver, Canada, who is using them to study multiple sclerosis (MS). "I don't think I'm being too optimistic to say that will happen in the next 5 years," she says. Sean Deoni, a physicist at Brown University, says that "any scanner on the planet can do this." An MRI scanner uses magnetic fields and radio waves to tickle the nuclei of hydrogen atoms—protons—in molecules of water, which makes up more than half of soft tissue. The protons act like little magnets, and the scanner's strong magnetic field makes them all point in one direction. A pulse of radio waves then tips the protons away from the magnetic field, causing them to twirl en masse, like so many gyroscopes. The protons then radiate radio waves of their own. © 2019 American Association for the Advancement of Scienc

Related chapters from BN8e: Chapter 2: Functional Neuroanatomy: The Nervous System and Behavior; Chapter 3: Neurophysiology: The Generation, Transmission, and Integration of Neural Signals
Related chapters from MM:Chapter 2: Cells and Structures: The Anatomy of the Nervous System; Chapter 3: Neurophysiology: The Generation, Transmission, and Integration of Neural Signals
Link ID: 26059 - Posted: 03.21.2019

By David Grossman The brain remains famously remains one of the most mysterious parts of the human body. The challenges of neuroscience are among the most daunting in the medical field. Expansion microscopy is a crucial element of that study, a chemical technique that expands a small specimen to make it more observable at the molecular level. A new technique allows scientists to expand microscopy so instead of focusing a single sell, it can explore full neural circuits, at a speed around 1,000 times faster than before. A struggle in studying live cells is watching them without altering their actions. Scientists work around this problem by using thin sheets of light to illuminate cells with a piece of complex technology called a lattice light sheet microscope. By combining this microscope with expansion microscopy, scientists at the Howard Hughes Medical Institute (HHMI) were able to expand the possibility of how they could study insect brains. “I thought they were full of it,” says Eric Betzig, now an HHMI investigator at the University of California, Berkeley, in a press statement. "They" refers to Ruixuan Gao and Shoh Asano of MIT, who wanted to use Betzig's lab to attempt their combining of the two practices. While a complex procedure involving high-end scientific equipment, at its heart “the idea does sound a bit crude,” Gao says. “We’re stretching tissues apart." When the experiment was over, Betzig says, “I couldn’t believe the quality of the data I was seeing. You could have knocked me over with a feather.” ©2019 Hearst Magazine Media, Inc

Related chapters from BN8e: Chapter 2: Functional Neuroanatomy: The Nervous System and Behavior
Related chapters from MM:Chapter 2: Cells and Structures: The Anatomy of the Nervous System
Link ID: 25886 - Posted: 01.21.2019

Laura Sanders Using laser light, ballooning tissue and innovative genetic tricks, scientists are starting to force brains to give up their secrets. By mixing and matching powerful advances in microscopy and cell biology, researchers have imaged intricate details of individual nerve cells in fruit flies and mice, and even controlled small groups of nerve cells in living mice. The techniques, published in two new studies, represent big steps forward for understanding how the brain operates, says molecular neuroscientist Hongkui Zeng of the Allen Institute for Brain Science in Seattle. “Without this kind of technology, we were only able to look at the soup level,” in which diverse nerve cells, or neurons, are grouped and analyzed together, she says. But the new studies show that nerve cells can be studied individually. That zoomed-in approach will begin to uncover the tremendous diversity that’s known to exist among cells, says Zeng, who was not involved in the research. “That is where the field is going. It’s very exciting to see that technologies are now enabling us to do that,” she says. These novel abilities came from multiple tools. At Howard Hughes Medical Institute’s Janelia Research Campus in Ashburn, Va., physicist Eric Betzig and his colleagues had developed a powerful microscope that can quickly peer deep into layers of brain tissue. Called a lattice light sheet microscope, the rig sweeps a thin sheet of laser light down through the brain, revealing cells’ structures. But like any microscope, it hits a wall when structures get really small, unable to resolve the most minute aspects of the scene. |© Society for Science & the Public 2000 - 2019.

Related chapters from BN8e: Chapter 2: Functional Neuroanatomy: The Nervous System and Behavior; Chapter 3: Neurophysiology: The Generation, Transmission, and Integration of Neural Signals
Related chapters from MM:Chapter 2: Cells and Structures: The Anatomy of the Nervous System; Chapter 3: Neurophysiology: The Generation, Transmission, and Integration of Neural Signals
Link ID: 25878 - Posted: 01.18.2019

Fiona McMillan Your brain has worked hard in 2018, so as the year draws to a close, take a moment to appreciate not only your marvelous network of brain cells, but those found in other species, too. Below is a list of where to find some of the year’s most stunning neuroscience images that reveal the hidden world of neurons in brilliant and breathtaking detail. In order to understand how the brain works, neuroscientists need to take a close look at how neuron networks are wired together. However this isn’t easy, after all just one cubic millimeter in the brain’s cerebral cortex contains around 50,000 neurons each making 6,000 connections with other neurons (give or take a few). Tracing a single network through this incredibly complex web is painstaking work. So, in recent years, researchers developed the Brainbow, a technique that allows individual neurons to be labelled with different fluorescent colors. Unfortunately, it still took months to trace the path of a single neuron across the mouse brain. To address this, in 2018 Takeshi Imai and his colleagues at Kyushu University, Kyoto University and the RIKEN Center for Developmental Biology in Japan took it to the next level. They developed the Tetbow, a method that produces extremely vivid colors enabling scientists to trace neuronal wiring across the whole mouse brain within a matter of days. Also, it’s really pretty. Tetbow provides colorful view of the olfactory bulbRichi Sakaguchi, Marcus N Leiwe, Takeshi Imai published in eLife Sciences under a Creative Commons CC BY 4.0 ©2019 Forbes Media LLC

Related chapters from BN8e: Chapter 2: Functional Neuroanatomy: The Nervous System and Behavior
Related chapters from MM:Chapter 2: Cells and Structures: The Anatomy of the Nervous System
Link ID: 25833 - Posted: 01.01.2019

By Kimon de Greef CAPE TOWN — A musician from South Africa had a tumor in his brain, so doctors opened a hole in his skull to remove it. But they had a crucial request: He must play his acoustic guitar during the surgery. The musician, Musa Manzini, a jazz bassist, was awake when the doctors performed the surgery last week, and video footage from the local media site News24 shows him strumming an acoustic guitar slowly as they operated. The technique, known as “awake craniotomy,” allows doctors to operate on delicate areas of the brain — like the right frontal lobe, the site of Mr. Manzini’s tumor — without causing damage. Presumably, had he hit a wrong note, it would have been an immediate signal for the surgeons to probe elsewhere. “It can be very difficult to tell the difference between the tumor and normal brain tissue,” said Dr. Basil Enicker, a specialist neurosurgeon who led the operation at Inkosi Albert Luthuli Central Hospital, in the coastal city of Durban. “Once you’re near a critical area, you can pick it up early, because he will tell you.” The surgery is not unusual. The first craniotomies date to prehistoric times, with fossil records showing that patients had holes drilled in their skulls — and survived — as early as 8,000 years ago. In the 1930s, the Canadian-American neurosurgeon Wilder Penfield pioneered modern craniotomies, which he used to treat epilepsy. The procedure has become fairly common globally since then, posing no greater technical challenge than regular brain surgery, Dr. Enicker said. But choosing patients is very important: People who cough, for example, or who cannot lie still for extended periods, are far more dangerous to operate on. © 2018 The New York Times Company

Related chapters from BN8e: Chapter 2: Functional Neuroanatomy: The Nervous System and Behavior; Chapter 3: Neurophysiology: The Generation, Transmission, and Integration of Neural Signals
Related chapters from MM:Chapter 2: Cells and Structures: The Anatomy of the Nervous System; Chapter 3: Neurophysiology: The Generation, Transmission, and Integration of Neural Signals
Link ID: 25815 - Posted: 12.22.2018

Researchers at Howard Hughes Medical Institute (HHMI) have mapped the neuroanatomical regions of the brain of a female mosquito (Aedes aegypti). The researchers constructed the map of groups of neurons by immunostaining the mosquito’s brain for Brp, a synaptic protein, and imaged the brain with confocal microscopy. The atlas was made freely available online on January 31st. “We are trying to build the field of mosquito neurobiology,” says HHMI neurobiologist Leslie Vosshall, who led the work, in a press release. She says she hopes that the new atlas will let mosquito researchers from around the world share data and better understand which parts of the mosquito brain direct different behaviors. “Somewhere in that female brain is the drive to sense humans, fly toward humans, land on humans, and bite and drink the blood of humans,” she says. “Somewhere in that brain is where decision making, motivation, and hunger reside.” © 1986 - 2018 The Scientist

Related chapters from BN8e: Chapter 2: Functional Neuroanatomy: The Nervous System and Behavior
Related chapters from MM:Chapter 2: Cells and Structures: The Anatomy of the Nervous System
Link ID: 25811 - Posted: 12.22.2018

Michael Eisenstein In March, researchers in Japan mapped the cellular organization of the mouse brain in unprecedented detail. Systems biologist Hiroki Ueda at the RIKEN Center for Biosystems Dynamics Research in Osaka, Japan, and his team created an atlas of the mouse brain using a technique called CUBIC-X, in which they chemically labelled every cell in the brain, then rendered the organ crystal-clear while also expanding its size tenfold1. From there, they used sophisticated imaging techniques to compile a comprehensive 3D neuronal survey — of some 72 million cells in all, Ueda says. The resulting atlas reduces the brain to a compact database of cellular addresses, which the team used to explore changes in various brain regions during development. Moving forward, the atlas could drive deeper explorations of brain structures that control behaviours such as the sleep–wake cycle. CUBIC-X is just one component in a growing toolbox of such methods, which exploit readily available chemicals to provide researchers with a window not just into the brain, but into virtually every organ in the body. Some are tissue-clearing methods that make opaque tissues transparent, whereas others complement tissue clearing with a proportional size increase that exposes molecular details to conventional microscopy. The choice comes down to the scientific question. There are many ways to achieve similar ends, and users should investigate the strengths and limitations of different methods before deciding which to use. The hunger for tissue-clearing techniques originated with neuroscientists, who were frustrated by their limited ability to trace the snaking routes of axons and dendrites in the brain. © 2018 Springer Nature Publishing AG

Related chapters from BN8e: Chapter 2: Functional Neuroanatomy: The Nervous System and Behavior
Related chapters from MM:Chapter 2: Cells and Structures: The Anatomy of the Nervous System
Link ID: 25755 - Posted: 12.06.2018

By R. Douglas Fields SAN DIEGO—In the textbook explanation for how information is encoded in the brain, neurons fire a rapid burst of electrical signals in response to inputs from the senses or other stimulation. The brain responds to a light turning on in a dark room with the short bursts of nerve impulses, called spikes. Each close grouping of spikes can be compared to a digital bit, the binary off-or-on code used by computers. Neuroscientists have long known, though, about other forms of electrical activity present in the brain. In particular, rhythmic voltage fluctuations in and around neurons—oscillations that occur at the same 60-cycle-per-second frequency as AC current in the U.S.—have caught the field’s attention. These gamma waves encode information by changing a signal’s amplitude, frequency or phase (relative position of one wave to another)—and the rhythmic voltage surges influence the timing of spikes. Heated debate has arisen in recent years as to whether these analog signals, akin to the ones used to broadcast AM or FM radio, may play a role in sorting, filtering and organizing the information flows required for cognitive processes. They may be instrumental in perceiving sensory inputs, focusing attention, making and recalling memories and coupling various cognitive processes into one coherent scene. It is thought that populations of neurons that oscillate at gamma frequencies may unite the neural activity in the same way the violin section of an orchestra is coupled together in time and rhythm with the percussion section to create symphonic music. When gamma waves oscillate in resonance, “you get very rich repertoires of behaviors,” says Wolf Singer, a neuroscientist at the Ernst Strüngmann Institute in Frankfurt, Germany, who researches gamma waves. Just as your car’s dashboard will vibrate in sync with the motor vibrating at a resonant frequency, so too can separate populations of neurons couple in resonance. © 2018 Scientific American

Related chapters from BN8e: Chapter 3: Neurophysiology: The Generation, Transmission, and Integration of Neural Signals; Chapter 2: Functional Neuroanatomy: The Nervous System and Behavior
Related chapters from MM:Chapter 3: Neurophysiology: The Generation, Transmission, and Integration of Neural Signals; Chapter 2: Cells and Structures: The Anatomy of the Nervous System
Link ID: 25731 - Posted: 11.29.2018

By Sharon Begley, The brain surgeon began as he always does, making an incision in the scalp and gently spreading it apart to expose the skull. He then drilled a 3-inch circular opening through the bone, down to the thick, tough covering called the dura. He sliced through that, and there in the little porthole he’d made was the glistening, blood-flecked, pewter-colored brain, ready for him to approach the way spies do a foreign embassy: He bugged it. Dr. Ashesh Mehta, a neurosurgeon at the Feinstein Institute for Medical Research on Long Island, was operating on his epilepsy patient to determine the source of seizures. But the patient agreed to something more: to be part of an audacious experiment whose ultimate goal is to translate thoughts into speech. While he was in there, Mehta carefully placed a flat array of microelectrodes on the left side of the brain’s surface, over areas involved in both listening to and formulating speech. By eavesdropping on the electrical impulses that crackle through the gray matter when a person hears in the “mind’s ear” what words he intends to articulate (often so quickly it’s barely conscious), then transmitting those signals wirelessly to a computer that decodes them, the electrodes and the rest of the system hold the promise of being the first “brain-computer interface” to go beyond movement and sensation. If all goes well, it will conquer the field’s Everest: developing a brain-computer interface that could enable people with a spinal cord injury, locked-in syndrome, ALS, or other paralyzing condition to talk again. © 2018 Scientific America

Related chapters from BN8e: Chapter 2: Functional Neuroanatomy: The Nervous System and Behavior; Chapter 19: Language and Lateralization
Related chapters from MM:Chapter 2: Cells and Structures: The Anatomy of the Nervous System; Chapter 15: Brain Asymmetry, Spatial Cognition, and Language
Link ID: 25708 - Posted: 11.21.2018

Sara Reardon A new technique that makes dead mice transparent and hard like plastic is giving researchers an unprecedented view of how different types of cell interact in the body. The approach lets scientists pinpoint specific tissues within an animal while scanning its entire body. The approach, called vDISCO, has already revealed surprising structural connections between organs, including hints about the extent to which brain injuries affect the immune system and nerves in other parts of the body. That could lead to better treatments for traumatic brain injury or stroke. Methods that turn entire organs clear have become popular in the past few years, because they allow scientists to study delicate internal structures without disturbing them. But removing organs from an animal’s body for analysis can make it harder to see the full effect of an injury or disease. And if scientists use older methods to make an entire mouse transparent, it can be difficult to ensure that the fluorescent markers used to label cells reach the deepest parts of an organ. The vDISCO technique overcomes many of these problems. By making the dead mice rigid and see-through, it can preserve their bodies for years, down to the structure of individual cells, says Ali Ertürk, a neuroscientist at Ludwig Maximilian University of Munich in Germany, who led the team that developed vDISCO. He presented the work this week at a meeting of the Society for Neuroscience in San Diego, California. © 2018 Springer Nature Limited.

Related chapters from BN8e: Chapter 2: Functional Neuroanatomy: The Nervous System and Behavior
Related chapters from MM:Chapter 2: Cells and Structures: The Anatomy of the Nervous System
Link ID: 25676 - Posted: 11.13.2018

Surgeons have tested the use of a fluorescent marker that can help them remove dangerous brain tumour cells from patients more accurately. The research was carried out on people who had suspected glioblastoma, the disease that killed British politician Dame Tessa Jowell in May, and the most common form of brain cancer. Treatment usually involves surgery to remove as much of the cancer as possible, but it can be challenging for surgeons to identify all the cancer cells while avoiding healthy brain tissue. Researchers said using the fluorescent marker helped distinguish the most aggressive cancer cells from other brain tissue and they hope this will ultimately improve patient survival. They used a compound called 5-aminolevulinic acid or 5-ALA, which the patient drinks. The compound glows pink when a light is shone on it. Previous research shows that 5-ALA accumulates in fast-growing cancer cells so it can act as a fluorescent marker of high-grade cells. The study was carried out on 99 patients with suspected high-grade gliomas – a kind of tumour –who were treated at Royal Liverpool hospital, King’s college hospital in London and Addenbrooke’s hospital in Cambridge. They were aged between 23 and 77, with an average age of 59. During their operations, surgeons reported seeing fluorescence in 85 patients and 81 of these were subsequently confirmed by pathologists to have high-grade disease. One was found to have low-grade disease and three could not be assessed. © 2018 Guardian News and Media Limited

Related chapters from BN8e: Chapter 2: Functional Neuroanatomy: The Nervous System and Behavior
Related chapters from MM:Chapter 2: Cells and Structures: The Anatomy of the Nervous System
Link ID: 25646 - Posted: 11.05.2018

Devika G. Bansal Tools that use light, drugs, or temperature to make neurons fire or rest on command have become a mainstay in neuroscience. Thermogenetics, which enables neurons to respond to temperature shifts, first took off with fruit flies about a decade ago, but is emerging as a new trick to manipulate the neural functioning of other model organisms. That’s due to some advantages it affords over optogenetics—the light-based technique that started it all. Genetic toolkits such as thermogenetics and optogenetics follow a basic recipe: scientists pick a receptor that responds to an external cue such as temperature or light, express the receptor in specific neurons as a switch that changes the cell’s voltage—triggering or inhibiting firing—and then use the cue to turn the neural switch on or off. Optogenetics revolutionized our understanding of how the brain’s wiring affects animal behavior. But it comes with drawbacks. For one, delivering light into the deepest regions of the brains of nontransparent animals is a challenge. In mice, this requires surgically inserting optical fibers into the brain, tethering the animal to the light source. Researchers working with adult fruit flies can cut a window through the head cuticle to access the brain. In both cases, the necessary experimental setups are invasive and often time and effort intensive. Additionally, the light intensity required for optogenetics tends to damage tissue. “You pump a lot of light through the optical fiber to activate neurons,” says Vsevolod Belousov, a biochemist at the Russian Academy of Sciences in Moscow who develops thermogenetic tools. “In general, this is not avoidable.” © 1986 - 2018 The Scientist

Related chapters from BN8e: Chapter 2: Functional Neuroanatomy: The Nervous System and Behavior; Chapter 8: General Principles of Sensory Processing, Touch, and Pain
Related chapters from MM:Chapter 2: Cells and Structures: The Anatomy of the Nervous System; Chapter 5: The Sensorimotor System
Link ID: 25636 - Posted: 11.02.2018

Ashley P. Taylor Two studies in mice published today (October 31) in Nature report the existence of several types of brain cells that had not been acknowledged before. These cell types are distinguished by their gene expression patterns, and within one cortical area, they perform distinct functions. For the gene expression study, led by the Allen Institute’s Hongkui Zeng, researchers performed single-cell RNA sequencing on more than 20,000 cells, most of which were neurons, in the visual cortex and the anterior lateral motor cortex of the mouse brain. Using this method, they identified 133 distinct cell types, both excitatory and inhibitory. They found that the various inhibitory neurons were present in both cortical areas but that the excitatory cell types kept to specific regions, as neuroscientists Aparna Bhaduri and Tomasz Nowakowski of the University of California, San Francisco, describe in an accompanying Nature commentary. “When we see not only cell types that people have identified before, but a number of new ones that are showing up in the data, it’s really exciting for us,” says Zeng in a press release. “It’s like we are able to put all the different pieces of the puzzle The other study, led by Karel Svoboda of the Janelia Research Campus of the Howard Hughes Medical Institute, examined the functions of two subtypes identified through the gene-expression study. These are excitatory cells called pyramidal tract neurons that reside within layer five of the anterior lateral motor cortex in mice. The researchers used optogenetics to activate either one neuronal subtype or the other in mice and at the same time monitored the activity of the two types of neurons during movement. They found that pyramidal tract neurons in the upper part of layer five seem to be involved in preparing for movement, whereas those in the lower part of layer five help execute it. © 1986 - 2018 The Scientist

Related chapters from BN8e: Chapter 2: Functional Neuroanatomy: The Nervous System and Behavior
Related chapters from MM:Chapter 2: Cells and Structures: The Anatomy of the Nervous System
Link ID: 25634 - Posted: 11.02.2018

Jeffrey M. Perkel Randal Burns recalls that the brain-science community was “abuzz” in 2011. Burns, a computer scientist at Johns Hopkins University in Baltimore, Maryland, was focusing on astrophysics and fluid dynamics data management at the time. But he was intrigued when Joshua Vogelstein, a neuroscientist and colleague at Johns Hopkins, told him that the first large-scale neural-connectivity data sets had just been collected and asked for his help to present them online. “It was the first time that you had data of that quality, at that resolution and scale, where you had the sense that you could build a neural map of an interesting portion of the brain,” says Burns. Vogelstein worked with Burns to build a system that would make those data — 20 trillion voxels’ worth — available to the larger neuroscience community. The team has now generalized the software to support different classes of imaging data and describes the system this week (J. T. Vogelstein et al. Nature Meth. 15, 846-847; 2018). NeuroData is a free, cloud-based collection of web services that supports large-scale neuroimaging data, from electron microscopy to magnetic resonance imaging and fluorescence photomicrographs. Key to its functionality, Vogelstein says, is the spatial database bossDB, which allows researchers to retrieve images of any section of the brain, at any resolution, and in several standard formats. Users can then explore those data using a tool known as Neuroglancer. As they navigate the images, the URL changes to reflect their specific view, allowing them to share particular visualizations with their colleagues. “These links become a core part of the way in which we communicate and pass data back and forth to one another,” says Forrest Collman, a neuroscientist at the Allen Institute for Brain Science in Seattle, Washington, and a co-author of the paper. © 2018 Springer Nature Limited.

Related chapters from BN8e: Chapter 2: Functional Neuroanatomy: The Nervous System and Behavior
Related chapters from MM:Chapter 2: Cells and Structures: The Anatomy of the Nervous System
Link ID: 25631 - Posted: 11.01.2018