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Bless You: Mouse Model Reveals Molecular Pathway Behind Sneezing

Amanda Heidt Qin Liu studies sneezing for a personal reason: her entire family suffers from seasonal allergies. “Until you experience something chronically, it is really hard to appreciate how disruptive it can be,” says Liu, a neuroscientist at Washington University in St. Louis. And given the role of sneezing in pathogen transmission, a better understanding of the molecular underpinnings of the phenomenon could one day help scientists mitigate or treat infectious diseases. When Liu first started looking into the mechanisms governing sneezing, she found that scientists know surprisingly little about how this process works. While prior research had identified a region in the brains of cats and humans that is active during sneezing, the exact pathways involved in turning a stimulus like pollen or spicy food into a sneeze remained unknown. To study sneezing in more detail, Liu and her team developed a new model by exposing mice to irritants such as histamine and capsaicin—a chemical in spicy peppers—and characterizing the physical properties of their resulting sneezes. Then, focusing on that previously discovered sneeze center, located in the brain’s ventromedial spinal trigeminal nucleus (SpV), Liu attempted to map the neural pathway. SNEEZE TRIGGER: When exposed to allergens such as histamine or chemical irritants such as capsaicin (1), sensory neurons in the noses of mice produce a peptide called neuromedin B (NMB). This signaling molecule binds to neurons in a region of the brainstem known as the ventromedial spinal trigeminal nucleus (SpV), which is known to be active during sneezing (2). These neurons send electrical signals (3) to neurons in another brainstem region called the caudal ventral respiratory group (cVRG), which controls exhalation, thus driving the initiation and propagation of sneezing (4). Ablating the nasal neurons or disrupting NMB signaling led to a significantly reduced sneezing reflex in the mice. WEB | PDF © 1986–2021 The Scientist.

How Computationally Complex Is a Single Neuron?

Allison Whitten Our mushy brains seem a far cry from the solid silicon chips in computer processors, but scientists have a long history of comparing the two. As Alan Turing put it in 1952: “We are not interested in the fact that the brain has the consistency of cold porridge.” In other words, the medium doesn’t matter, only the computational ability. Today, the most powerful artificial intelligence systems employ a type of machine learning called deep learning. Their algorithms learn by processing massive amounts of data through hidden layers of interconnected nodes, referred to as deep neural networks. As their name suggests, deep neural networks were inspired by the real neural networks in the brain, with the nodes modeled after real neurons — or, at least, after what neuroscientists knew about neurons back in the 1950s, when an influential neuron model called the perceptron was born. Since then, our understanding of the computational complexity of single neurons has dramatically expanded, so biological neurons are known to be more complex than artificial ones. But by how much? To find out, David Beniaguev, Idan Segev and Michael London, all at the Hebrew University of Jerusalem, trained an artificial deep neural network to mimic the computations of a simulated biological neuron. They showed that a deep neural network requires between five and eight layers of interconnected “neurons” to represent the complexity of one single biological neuron. All Rights Reserved © 2021

The Brain Doesn’t Think the Way You Think It Does

Jordana Cepelewicz Neuroscientists are the cartographers of the brain’s diverse domains and territories — the features and activities that define them, the roads and highways that connect them, and the boundaries that delineate them. Toward the front of the brain, just behind the forehead, is the prefrontal cortex, celebrated as the seat of judgment. Behind it lies the motor cortex, responsible for planning and coordinating movement. To the sides: the temporal lobes, crucial for memory and the processing of emotion. Above them, the somatosensory cortex; behind them, the visual cortex. Not only do researchers often depict the brain and its functions much as mapmakers might draw nations on continents, but they do so “the way old-fashioned mapmakers” did, according to Lisa Feldman Barrett, a psychologist at Northeastern University. “They parse the brain in terms of what they’re interested in psychologically or mentally or behaviorally,” and then they assign the functions to different networks of neurons “as if they’re Lego blocks, as if there are firm boundaries there.” But a brain map with neat borders is not just oversimplified — it’s misleading. “Scientists for over 100 years have searched fruitlessly for brain boundaries between thinking, feeling, deciding, remembering, moving and other everyday experiences,” Barrett said. A host of recent neurological studies further confirm that these mental categories “are poor guides for understanding how brains are structured or how they work.” Neuroscientists generally agree about how the physical tissue of the brain is organized: into particular regions, networks, cell types. But when it comes to relating those to the task the brain might be performing — perception, memory, attention, emotion or action — “things get a lot more dodgy,” said David Poeppel, a neuroscientist at New York University. All Rights Reserved © 2021

Tapping Into the Brain to Help a Paralyzed Man Speak

By Pam Belluck He has not been able to speak since 2003, when he was paralyzed at age 20 by a severe stroke after a terrible car crash. Now, in a scientific milestone, researchers have tapped into the speech areas of his brain — allowing him to produce comprehensible words and sentences simply by trying to say them. When the man, known by his nickname, Pancho, tries to speak, electrodes implanted in his brain transmit signals to a computer that displays his intended words on the screen. His first recognizable sentence, researchers said, was, “My family is outside.” The achievement, published on Wednesday in the New England Journal of Medicine, could eventually help many patients with conditions that steal their ability to talk. “This is farther than we’ve ever imagined we could go,” said Melanie Fried-Oken, a professor of neurology and pediatrics at Oregon Health & Science University, who was not involved in the project. Three years ago, when Pancho, now 38, agreed to work with neuroscience researchers, they were unsure if his brain had even retained the mechanisms for speech. “That part of his brain might have been dormant, and we just didn’t know if it would ever really wake up in order for him to speak again,” said Dr. Edward Chang, chairman of neurological surgery at University of California, San Francisco, who led the research. The team implanted a rectangular sheet of 128 electrodes, designed to detect signals from speech-related sensory and motor processes linked to the mouth, lips, jaw, tongue and larynx. In 50 sessions over 81 weeks, they connected the implant to a computer by a cable attached to a port in Pancho’s head, and asked him to try to say words from a list of 50 common ones he helped suggest, including “hungry,” “music” and “computer.” As he did, electrodes transmitted signals through a form of artificial intelligence that tried to recognize the intended words. © 2021 The New York Times Company

Related chapters from BN: Chapter 19: Language and Lateralization; Chapter 11: Motor Control and Plasticity
Related chapters from MM:Chapter 15: Language and Lateralization; Chapter 5: The Sensorimotor System
Link ID: 27913 - Posted: 07.17.2021

X-ray technology allows researchers to measure from synapse to whole brain level

Researchers at the University of Chicago and Argonne National Laboratory have imaged an entire mouse brain across five orders of magnitude of resolution, a step which researchers say will better connect existing imaging approaches and uncover new details about the structure of the brain. The advance, which was published on June 9 in NeuroImage, will allow scientists to connect biomarkers at the microscopic and macroscopic level. It leveraged existing advanced X-ray microscopy techniques to bridge the gap between MRI and electron microscopy imaging, providing a viable pipeline for multiscale whole brain imaging within the same brain. “Our lab is really interested in mapping brains at multiple scales to get an unbiased description of what brains look like,” said senior author Narayanan “Bobby” Kasthuri, assistant professor of neurobiology at UChicago and scientist at Argonne. “When I joined the faculty here, one of the first things I learned was that Argonne had this extremely powerful X-ray microscope, and it hadn’t been used for brain mapping yet, so we decided to try it out.” The microscope uses a type of imaging called synchrotron-based X-ray tomography, which can be likened to a “micro-CT”, or micro-computerized tomography scan. Thanks to the powerful X-rays produced by the synchrotron particle accelerator at Argonne, the researchers were able to image the entire mouse brain—roughly one cubic centimeter—at the resolution of a micron, 1/10,000 of a centimeter. It took roughly six hours to collect images of the entire brain, adding up to around 2 terabytes of data. This is one of the fastest approaches for whole brain imaging at this level of resolution.

Related chapters from BN: Chapter 2: Functional Neuroanatomy: The Cells and Structure of the Nervous System
Related chapters from MM:Chapter 2: Neurophysiology: The Generation, Transmission, and Integration of Neural Signals
Link ID: 27910 - Posted: 07.17.2021

A racist scientist built a collection of human skulls. Should we still study them?

By Lizzie Wade They were buried on a plantation just outside Havana. Likely few, if any, thought of the place as home. Most apparently grew up in West Africa, surrounded by family and friends. The exact paths that led to each of them being ripped from those communities and sold into bondage across the sea cannot be retraced. We don’t know their names and we don’t know their stories because in their new world of enslavement those truths didn’t matter to people with the power to write history. All we can tentatively say: They were 51 of nearly 5 million enslaved Africans brought to Caribbean ports and forced to labor in the islands’ sugar and coffee fields for the profit of Europeans. Nor do we know how or when the 51 died. Perhaps they succumbed to disease, or were killed through overwork or by a more explicit act of violence. What we do know about the 51 begins only with a gruesome postscript: In 1840, a Cuban doctor named José Rodriguez Cisneros dug up their bodies, removed their heads, and shipped their skulls to Philadelphia. He did so at the request of Samuel Morton, a doctor, anatomist, and the first physical anthropologist in the United States, who was building a collection of crania to study racial differences. And thus the skulls of the 51 were turned into objects to be measured and weighed, filled with lead shot, and measured again. Morton, who was white, used the skulls of the 51—as he did all of those in his collection—to define the racial categories and hierarchies still etched into our world today. After his death in 1851, his collection continued to be studied, added to, and displayed. In the 1980s, the skulls, now at the University of Pennsylvania Museum of Archaeology and Anthropology, began to be studied again, this time by anthropologists with ideas very different from Morton’s. They knew that society, not biology, defines race. © 2021 American Association for the Advancement of Science.

Related chapters from BN: Chapter 6: Evolution of the Brain and Behavior; Chapter 2: Functional Neuroanatomy: The Cells and Structure of the Nervous System
Related chapters from MM:Chapter 2: Neurophysiology: The Generation, Transmission, and Integration of Neural Signals
Link ID: 27902 - Posted: 07.10.2021

Neurons Unexpectedly Encode Information in the Timing of Their Firing

Elena Renken For decades, neuroscientists have treated the brain somewhat like a Geiger counter: The rate at which neurons fire is taken as a measure of activity, just as a Geiger counter’s click rate indicates the strength of radiation. But new research suggests the brain may be more like a musical instrument. When you play the piano, how often you hit the keys matters, but the precise timing of the notes is also essential to the melody. “It’s really important not just how many [neuron activations] occur, but when exactly they occur,” said Joshua Jacobs, a neuroscientist and biomedical engineer at Columbia University who reported new evidence for this claim last month in Cell. For the first time, Jacobs and two coauthors spied neurons in the human brain encoding spatial information through the timing, rather than rate, of their firing. This temporal firing phenomenon is well documented in certain brain areas of rats, but the new study and others suggest it might be far more widespread in mammalian brains. “The more we look for it, the more we see it,” Jacobs said. Abstractions navigates promising ideas in science and mathematics. Journey with us and join the conversation. Some researchers think the discovery might help solve a major mystery: how brains can learn so quickly. The phenomenon is called phase precession. It’s a relationship between the continuous rhythm of a brain wave — the overall ebb and flow of electrical signaling in an area of the brain — and the specific moments that neurons in that brain area activate. A theta brain wave, for instance, rises and falls in a consistent pattern over time, but neurons fire inconsistently, at different points on the wave’s trajectory. In this way, brain waves act like a clock, said one of the study’s coauthors, Salman Qasim, also of Columbia. They let neurons time their firings precisely so that they’ll land in range of other neurons’ firing — thereby forging connections between neurons. All Rights Reserved © 2021

Related chapters from BN: Chapter 8: General Principles of Sensory Processing, Touch, and Pain; Chapter 17: Learning and Memory
Related chapters from MM:Chapter 5: The Sensorimotor System; Chapter 13: Memory and Learning
Link ID: 27898 - Posted: 07.08.2021

Controlling nerve cells with light opened new ways to study the brain

By Laura Sanders Some big scientific discoveries aren’t actually discovered. They are borrowed. That’s what happened when scientists enlisted proteins from an unlikely lender: green algae. Cells of the algal species Chlamydomonas reinhardtii are decorated with proteins that can sense light. That ability, first noticed in 2002, quickly caught the attention of brain scientists. A light-sensing protein promised the power to control neurons — the brain’s nerve cells — by providing a way to turn them on and off, in exactly the right place and time. Nerve cells genetically engineered to produce the algal proteins become light-controlled puppets. A flash of light could induce a quiet neuron to fire off signals or force an active neuron to fall silent. “This molecule is the light sensor that we needed,” says vision neuroscientist Zhuo-Hua Pan, who had been searching for a way to control vision cells in mice’s retinas. The method enabled by these loaner proteins is now called optogenetics, for its combination of light (opto) and genes. In less than two decades, optogenetics has led to big insights into how memories are stored, what creates perceptions and what goes wrong in the brain during depression and addiction. Using light to drive the activity of certain nerve cells, scientists have toyed with mouse hallucinations: Mice have seen lines that aren’t there and have remembered a room they had never been inside. Scientists have used optogenetics to make mice fight, mate and eat, and even given blind mice sight. In a big first, optogenetics recently restored aspects of a blind man’s vision. © Society for Science & the Public 2000–2021.

Related chapters from BN: Chapter 17: Learning and Memory; Chapter 3: Neurophysiology: The Generation, Transmission, and Integration of Neural Signals
Related chapters from MM:Chapter 13: Memory and Learning; Chapter 3: The Chemistry of Behavior: Neurotransmitters and Neuropharmacology
Link ID: 27861 - Posted: 06.19.2021

A deep look at a speck of human brain reveals never-before-seen quirks

Laura Sanders A new view of the human brain shows its cellular residents in all their wild and weird glory. The map, drawn from a tiny piece of a woman’s brain, charts the varied shapes of 50,000 cells and 130 million connections between them. This intricate map, named H01 for “human sample 1,” represents a milestone in scientists’ quest to provide ever more detailed descriptions of a brain (SN: 2/7/14). “It’s absolutely beautiful,” says neuroscientist Clay Reid at the Allen Institute for Brain Science in Seattle. “In the best possible way, it’s the beginning of something very exciting.” Scientists at Harvard University, Google and elsewhere prepared and analyzed the brain tissue sample. Smaller than a sesame seed, the bit of brain was about a millionth of an entire brain’s volume. It came from the cortex — the brain’s outer layer responsible for complex thought — of a 45-year-old woman undergoing surgery for epilepsy. After it was removed, the brain sample was quickly preserved and stained with heavy metals that revealed cellular structures. The sample was then sliced into more than 5,000 wafer-thin pieces and imaged with powerful electron microscopes. Computational programs stitched the resulting images back together and artificial intelligence programs helped scientists analyze them. A short description of the resulting view was published as a preprint May 30 to bioRxiv.org. The full dataset is freely available online. black background with green and purple nerve cells with lots of long tendrils These two neurons are mirror symmetrical. It’s unclear why these cells take these shapes. Lichtman Lab/Harvard University, Connectomics Team/Google For now, researchers are just beginning to see what’s there. “We have really just dipped our toe into this dataset,” says study coauthor Jeff Lichtman, a developmental neurobiologist at Harvard University. Lichtman compares the brain map to Google Earth: “There are gems in there to find, but no one can say they’ve looked at the whole thing.” © Society for Science & the Public 2000–2021.

Breakthrough brain-scanning method beckons new neurological discoveries

By Thomas Ling Neuroscientists are poised to gain new insights into how our minds work, thanks to a breakthrough in non-invasive 3D brain scanning. Testing the new technique – which is called diffuse optical localisation imaging (DOLI) – researchers from the University of Zurich injected a live mouse with special fluorescent microdroplets that became distributed throughout the bloodstream. Highly efficient short-wave cameras (which take advantage of a near-infrared spectral window) tracked the fluorescent to draw a map of the deep cerebral network within the mouse’s brain. Previous microscopy techniques generated unclear images due to intense light scattering. However, the DOLI technique can create a clear picture of the brain at the capillary level by using a fluorescent filled with tiny lead-sulfide-based particles called quantum dots. Additionally, unlike past procedures, DOLI does not need to break the animal’s skull and scalp to work. It is hoped the new non-invasive technique will lead to a better understanding of how brains work, including how neurological diseases first form. “Enabling high-resolution optical observations in deep living tissues represents a long-standing goal in the biomedical imaging field,” said research team leader Prof Daniel Razansky, who published the group’s findings in Optica, The Optical Society’s journal. (C) BBC

Paralysed man uses ‘mindwriting’ brain computer to compose sentences

Ian Sample Science editor A man who was paralysed from the neck down in an accident more than a decade ago has written sentences using a computer system that turns imagined handwriting into words. It is the first time scientists have created sentences from brain activity linked to handwriting and paves the way for more sophisticated devices to help paralysed people communicate faster and more clearly. The man, known as T5, who is in his 60s and lost practically all movement below his neck after a spinal cord injury in 2007, was able to write 18 words a minute when connected to the system. On individual letters, his “mindwriting” was more than 94% accurate. Frank Willett, a research scientist on the project at Stanford University in California, said the approach opened the door to decoding other imagined actions, such as 10-finger touch typing and attempted speech for patients who had permanently lost their voices. “Instead of detecting letters, the algorithm would be detecting syllables, or rather phonemes, the fundamental unit of speech,” he said. Amy Orsborn, an expert in neural engineering at the University of Washington in Seattle, who was not involved in the work, called it “a remarkable advance” in the field. Scientists have developed numerous software packages and devices to help paralysed people communicate, ranging from speech recognition programs to the muscle-driven cursor system created for the late Cambridge cosmologist Stephen Hawking, who used a screen on which a cursor automatically moved over the letters of the alphabet. To select one, and to build up words, he simply tensed his cheek. © 2021 Guardian News & Media Limited

Related chapters from BN: Chapter 2: Functional Neuroanatomy: The Cells and Structure of the Nervous System; Chapter 19: Language and Lateralization
Related chapters from MM:Chapter 2: Neurophysiology: The Generation, Transmission, and Integration of Neural Signals; Chapter 15: Language and Lateralization
Link ID: 27822 - Posted: 05.15.2021

Scientists remotely controlled the social behavior of mice with light

By Charles Q. Choi With the help of headsets and backpacks on mice, scientists are using light to switch nerve cells on and off in the rodents’ brains to probe the animals’ social behavior, a new study shows. These remote control experiments are revealing new insights on the neural circuitry underlying social interactions, supporting previous work suggesting minds in sync are more cooperative, researchers report online May 10 in Nature Neuroscience. The new devices rely on optogenetics, a technique in which researchers use bursts of light to activate or suppress the brain nerve cells, or neurons, often using tailored viruses to genetically modify cells so they respond to illumination (SN: 1/15/10). Scientists have used optogenetics to probe neural circuits in mice and other lab animals to yield insights on how they might work in humans (SN: 10/22/19). Optogenetic devices often feed light to neurons via fiber-optic cables, but such tethers can interfere with natural behaviors and social interactions. While scientists recently developed implantable wireless optogenetic devices, these depend on relatively simple remote controls or limited sets of preprogrammed instructions. These new fully implantable optogenetic arrays for mice and rats can enable more sophisticated research. Specifically, the researchers can adjust each device’s programming during the course of experiments, “so you can target what an animal does in a much more complex way,” says Genia Kozorovitskiy, a neurobiologist at Northwestern University in Evanston, Ill. © Society for Science & the Public 2000–2021.

Researchers wirelessly record human brain activity during normal life activities

Researchers are now able to wirelessly record the directly measured brain activity of patients living with Parkinson’s disease and to then use that information to adjust the stimulation delivered by an implanted device. Direct recording of deep and surface brain activity offers a unique look into the underlying causes of many brain disorders; however, technological challenges up to this point have limited direct human brain recordings to relatively short periods of time in controlled clinical settings. This project, published in the journal Nature Biotechnology, was funded by the National Institutes of Health’s Brain Research Through Advancing Innovative Neurotechnologies (BRAIN) Initiative. “This is really the first example of wirelessly recording deep and surface human brain activity for an extended period of time in the participants’ home environment,” said Kari Ashmont, Ph.D., project manager for the NIH BRAIN Initiative. “It is also the first demonstration of adaptive deep brain stimulation at home.” Deep brain stimulation (DBS) devices are approved by the U. S. Food and Drug Administration for the management of Parkinson’s disease symptoms by implanting a thin wire, or electrode, that sends electrical signals into the brain. In 2018, the laboratory of Philip Starr, M.D., Ph.D. at the University of California, San Francisco, developed an adaptive version of DBS that adapts its stimulation only when needed based on recorded brain activity. In this study, Dr. Starr and his colleagues made several additional improvements to the implanted technology.

The Fading Dream of the Computer Brain

By Noah Hutton Twelve years ago, when I graduated college, I was well aware of the Silicon Valley hype machine, but I considered the salesmanship of private tech companies a world away from objective truths about human biology I had been taught in neuroscience classes. At the time, I saw the neuroscientist Henry Markram proclaim in a TED talk that he had figured out a way to simulate an entire human brain on supercomputers within 10 years. This computer-simulated organ would allow scientists to instantly and noninvasively test new treatments for disorders and diseases, moving us from research that depends on animal experimentation and delicate interventions on living people to an “in silico” approach to neuroscience. My 22-year-old mind didn’t clock this as an overhyped proposal. Instead, it felt exciting and daring, the kind of moment that transforms a distant scientific pipe dream into a suddenly tangible goal and motivates funders and fellow researchers to think bigger. And so I began a 10-year documentary project following Markram and his Blue Brain Project, with the start of the film coinciding with the beginning of an era of big neuroscience where the humming black boxes produced by Silicon Valley came to be seen as the great new hope for making sense of the black boxes between our ears. My decade-long journey documenting Markram’s vision has no clear answers except perhaps one: that flashy presentations and sheer ambition are poor indicators of success when it comes to understanding the complex biological mechanisms of brains. Today, as we bear witness to a game of Pong being mind-controlled by a monkey as part of a typically bombastic demonstration by Elon Musk’s start-up Neuralink, there is more of a need than ever to unwind the cycles of hype in order to grapple with what the future of brain technology and neuroscience have in store for humanity. © 2021 Scientific American

Related chapters from BN: Chapter 2: Functional Neuroanatomy: The Cells and Structure of the Nervous System; Chapter 17: Learning and Memory
Related chapters from MM:Chapter 2: Neurophysiology: The Generation, Transmission, and Integration of Neural Signals; Chapter 13: Memory and Learning
Link ID: 27794 - Posted: 05.01.2021

Ultrasound reads monkey brains, opening new way to control machines with thought

By Kelly Servick The most advanced mind-controlled devices being tested in humans rely on tiny wires inserted into the brain. Now researchers have paved the way for a less invasive option. They’ve used ultrasound imaging to predict a monkey’s intended eye or hand movements—information that could generate commands for a robotic arm or computer cursor. If the approach can be improved, it may offer people who are paralyzed a new means of controlling prostheses without equipment that penetrates the brain. “This study will put [ultrasound] on the map as a brain-machine interface technique,” says Stanford University neuroscientist Krishna Shenoy, who was not involved in the new work. “Adding this to the toolkit is spectacular.” Doctors have long used sound waves with frequencies beyond the range of human hearing to create images of our innards. A device called a transducer sends ultrasonic pings into the body, which bounce back to indicate the boundaries between different tissues About a decade ago, researchers found a way to adapt ultrasound for brain imaging. The approach, known as functional ultrasound, uses a broad, flat plane of sound instead of a narrow beam to capture a large area more quickly than with traditional ultrasound. Like functional magnetic resonance imaging (fMRI), functional ultrasound measures changes in blood flow that indicate when neurons are active and expending energy. But it creates images with much finer resolution than fMRI and doesn’t require participants to lie in a massive scanner. The technique still requires removing a small piece of skull, but unlike implanted electrodes that read neurons’ electrical activity directly, it doesn’t involve opening the brain’s protective membrane, notes neuroscientist Richard Andersen of the California Institute of Technology (Caltech), a co-author of the new study. Functional ultrasound can read from regions deep in the brain without penetrating the tissue. © 2021 American Association for the Advancement of Science.

Related chapters from BN: Chapter 2: Functional Neuroanatomy: The Cells and Structure of the Nervous System; Chapter 11: Motor Control and Plasticity
Related chapters from MM:Chapter 2: Neurophysiology: The Generation, Transmission, and Integration of Neural Signals; Chapter 5: The Sensorimotor System
Link ID: 27741 - Posted: 03.23.2021

How is this horse feeling? New mobile brain wave reader could tell

By Christa Lesté-Lasserre The famed stallion Black Beauty felt joy, excitement, and even heartbreak—or so he tells us in the 1877 novel that bears his name. Now, scientists say they’ve been able to detect feelings in living animals by getting them straight from the horse’s mouth—or in this case, its head. Researchers have devised a new, mobile headband that detects brain waves in horses, which could eventually be used with other species. “This is a real breakthrough,” says Katherine Houpt, a veterinary behaviorist at Cornell University who was not involved with the work. The device, she says, “gets into the animals’ minds” with objectivity and less guesswork. Ethologist Martine Hausberger had the idea while investigating whether stressed horses had a harder time learning to open a sliding door over a food box. (Spoiler alert: They do.) Hausberger, of the University of Rennes, noticed some of the animals—specifically, those living in cramped spaces—were paying less attention to the lessons. Were they depressed? An electroencephalogram (EEG) could theoretically pick up on such a mental state. Scientists have used the devices, which record waves of electrical impulses in the brain, since the early 1900s to study epilepsy and sleep patterns. More recently, they’ve discovered that certain EEG waves can signal depression, anxiety, and even contentedness in humans. EEG studies in rodents, farm animals, and pets, meanwhile, have revealed how they react to being touched by a human or undergoing anesthesia. But so far, no one had found a way to record brain waves in animals while they move around. © 2021 American Association for the Advancement of Science.

Three visions of the future, inspired by neuroscience’s past and present

By Laura Sanders A century ago, science’s understanding of the brain was primitive, like astronomy before telescopes. Certain brain injuries were known to cause specific problems, like loss of speech or vision, but those findings offered a fuzzy view. Anatomists had identified nerve cells, or neurons, as key components of the brain and nervous system. But nobody knew how these cells collectively manage the brain’s sophisticated control of behavior, memory or emotions. And nobody knew how neurons communicate, or the intricacies of their connections. For that matter, the research field known as neuroscience — the science of the nervous system — did not exist, becoming known as such only in the 1960s. Over the last 100 years, brain scientists have built their telescopes. Powerful tools for peering inward have revealed cellular constellations. It’s likely that over 100 different kinds of brain cells communicate with dozens of distinct chemicals. A single neuron, scientists have discovered, can connect to tens of thousands of other cells. Yet neuroscience, though no longer in its infancy, is far from mature. Today, making sense of the brain’s vexing complexity is harder than ever. Advanced technologies and expanded computing capacity churn out torrents of information. “We have vastly more data … than we ever had before, period,” says Christof Koch, a neuroscientist at the Allen Institute in Seattle. Yet we still don’t have a satisfying explanation of how the brain operates. We may never understand brains in the way we understand rainbows, or black holes, or DNA. © Society for Science & the Public 2000–2021.

Dr. John Bentson, Who Invented a Better Brain-Imaging Tool, Dies at 83

By Alex Vadukul In the early 1970s, the field of neuroradiology was still in its formative years, and among its early practitioners was Dr. John Bentson, at UCLA Medical Center in Los Angeles. As he helped patients with the aid of new technology like the CT scan and computer imaging, he saw an opportunity for innovation. A subspecialty of radiology, neuroradiology involves diagnosing and treating ailments in the brain, spinal cord and nerves. One tool used in treatment is the combination of an angiographic guidewire and catheter, essentially a slender wire and tube. Inserted through the leg, it can aid with the injection of contrast dye for diagnostic brain imaging and the treatment of aneurysms. At the time, however, guidewires were rigid and at worst could injure a blood vessel. Dr. Bentson decided to design a better type. He conceived of a more supple guidewire that also featured a flexible tip, and after UCLA built an early prototype for him, other neuroradiologists started using his model. Cook Medical began manufacturing the device in 1973, and it’s still in use today, commonly known as a Bentson guidewire. Dr. Bentson died at 83 on Dec. 28 at a hospital in Los Angeles. The cause was complications of Covid-19, his daughter Dr. Erika Drazan said. “He liked to push boundaries if he thought he could help the patient,” she said. “He liked saying that the vessels in the body are just like a tree, and that he could get where he wanted through them by feel.” Thousands of patients have benefited from his innovation, The American Society of Neuroradiology said after his death. John Reinert Bentson was born on May 15, 1937, in Viroqua, Wis., to Carl and Stella (Hagen) Bentson, who were of Norwegian heritage. He was raised on his family’s dairy farm, going to school in the winter on wooden skis. His mother prepared Norwegian fare like lutefisk. © 2021 The New York Times Company

Famous brain sketches come to life again as embroideries

By Laura Sanders In the late 1800s, Santiago Ramón y Cajal, a Spanish brain scientist, spent long hours in his attic drawing elaborate cells. His careful, solitary work helped reveal individual cells of the brain that together create wider networks. For those insights, Cajal received a Nobel Prize for physiology or medicine in 1906. Now, a group of embroiderers has traced those iconic cell images with thread, paying tribute to the pioneering drawings that helped us see the brain clearly. The Cajal Embroidery Project was launched in March of 2020 by scientists at the University of Edinburgh. Over a hundred volunteers — scientists, artists and embroiderers — sewed panels that will ultimately be stitched into a tapestry, a project described in the December Lancet Neurology. Catherine Abbott, a neuroscientist at the University of Edinburgh, had the idea while talking with her colleague Jane Haley, who was planning an exhibit of Cajal’s drawings. These meticulous drawings re-created nerve cells, or neurons, and other types of brain cells, including support cells called astrocytes. “I said, off the cuff, ‘Wouldn’t it be lovely to embroider some of them?’” © Society for Science & the Public 2000–2021.

Documentary follows implosion of billion-euro brain project

Alison Abbott In October 2013, I attended the launch of the Human Brain Project in Lausanne, Switzerland, as correspondent for Nature. I hoped to leave with a better understanding of the exact mission of the baffling billion-euro enterprise, but I was frustrated. Things became clear the following year, when the project fell spectacularly, and very publicly, apart. Noah Hutton’s documentary In Silico captures a sense of what it was like behind the scenes of the project, which was supported with great fanfare by the European Commission. It had been hyped as a quantum leap in understanding how the human brain works. Instead, it left a trail of angry neuroscientists across Europe. Yet aspects of what went so expensively wrong still remain elusive. In Silico is more about the back story of the Human Brain Project (HBP). Hutton was 22 years old when he watched a 2009 talk by Henry Markram, the controversial figure who later became the first director of the HBP. Markham was speaking about the Blue Brain Project, a major initiative he had launched a few years before at one of Europe’s top universities, the Swiss Federal Institute of Technology in Lausanne, with generous funding from the Swiss government. He claimed that he would — with the help of a supercomputer related to the one that beat world chess champion Garry Kasparov in 1997 — simulate an entire rodent brain within a decade. He planned to build it from information about the brain’s tens of millions of individual neurons. © 2020 Springer Nature Limited

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