Chapter 1. Structure and Function: Neuroanatomy and Research Methods

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By Brandon Keim When Lauren Strohacker received her second Covid-19 vaccine dose in the spring of 2021, she rejoiced. It meant she could see her friends again, go to concerts and live with far less fear that an infection might leave her physically or financially devastated. But it became a bittersweet memory. Not long after Ms. Strohacker, an artist based in Knox County, Tenn., returned home from the vaccination site, she read an article about monkeys used in testing Covid vaccines. “I thought, I’m afraid of a stupid needle,” she said. “And these animals have to deal with this all the time.” She reflected on how her newfound freedom, and quite possibly her health, came at the expense of animals suffering or dying to develop the vaccines. Merely being grateful for those animals seemed insufficient; Ms. Strohacker wanted to give something tangible in return. A little online research returned the National Anti-Vivisection Society’s sanctuary fund, which supports the care of retired lab animals. She made a small donation. “To give thanks was the very least I could do,” Ms. Strohacker said. Her gesture embodies a voice that is not often heard in debates about the use of animals in biomedical research. These tend to be polarized between opponents of the research, who claim that it is unethical and the benefits are overstated, and proponents who argue that the benefits are enormous and justify the harms to animals. The advancement of animal-free methods for developing drugs and testing product safety does raise the possibility that, at least in some cases, the use of animals can be avoided. But it will take years for that to happen, and few researchers think the use of animals will cease altogether. So long as animals are used, then, the question remains: What do people owe them? © 2023 The New York Times Company

Keyword: Animal Rights
Link ID: 28636 - Posted: 01.25.2023

ByDennis Normile After 5 years of planning and debate, China has finally launched its ambitious contribution to neuroscience, the China Brain Project (CBP). Budgeted at 5 billion yuan ($746 million) under the latest 5-year plan, the CBP will likely get additional money under future plans, putting it in the same league as the U.S. Brain Research Through Advancing Innovative Neurotechnologies (BRAIN) Initiative, which awarded $2.4 billion in grants through 2021, and the EU Human Brain Project, budgeted at $1.3 billion. The project “is really on the move,” says one of its architects, neuroscientist Mu-ming Poo, head of the Chinese Academy of Sciences’s (CAS’s) Institute of Neuroscience (ION). The details of the project remain murky. But China’s researchers “seem to be building on their strengths, which is great,” says neuroscientist Robert Desimone of the Massachusetts Institute of Technology, who collaborates with colleagues in China. The CBP focuses on three broad areas: the neural basis of cognitive functions, diagnosing and treating brain disorders, and brain-inspired computing. Monkey studies will play a key part in the research, and project leaders hope the virtual absence of animal rights activism in China will help lure talent from overseas. (Poo himself studied and worked in the United States for 40 years, including a decade at the University of California, Berkeley, and moved to China full-time in 2009.) Neuroscience was first identified as a priority in China’s 2016 Five-Year Plan, but soon became “a very contentious project,” says Denis Simon, a China science policy expert at Duke University. “There was hefty debate and discussion about how to choose projects, set priorities, and allocate funds,” Simon says. Deliberations dragged on until brain science was again designated as a priority field in the 2021 Five-Year Plan, adopted in March 2021. Funding for the CBP finally started to flow in December 2021, Poo says.

Keyword: Animal Rights
Link ID: 28483 - Posted: 09.21.2022

By Eduardo Medina An infection caused by a brain-eating amoeba killed a child who swam in a Nebraska river over the weekend, health officials said Friday. It was the first such death in the state’s history and the second in the Midwest this summer. The child, whose name was not released by officials, contracted the infection, known as primary amebic meningoencephalitis, while swimming with family in a shallow part of the Elkhorn River in eastern Nebraska on Sunday, according to the Douglas County Health Department. At a news conference on Thursday, health officials said the typically fatal infection is caused by Naegleria fowleri, also known as brain-eating amoeba, and most likely led to the child’s death. The Centers for Disease Control and Prevention confirmed Friday that it had found Naegleria fowleri in the child’s cerebrospinal fluid. Last month, a person in Missouri died because of the same amoeba infection, according to the Missouri Department of Health and Senior Services. The person had been swimming at the beach at Lake of Three Fires State Park in Iowa. Out of precaution, the Iowa Department of Public Health closed the lake’s beach for about three weeks. The brain-eating amoebas, which are single-cell organisms, usually thrive in warm freshwater lakes, rivers, canals and ponds, though they can also be present in soil. They enter the body through the nose and then move into the brain. People usually become infected while swimming in lakes and rivers, according to the C.D.C. Infections from brain-eating amoeba are extremely rare: From 2012 to 2021, only 31 cases were reported in the U.S., according to the C.D.C. An infection, however, almost always leads to death. In the United States, there were 143 infections from 1962 through 2017. All but four of them were fatal, the C.D.C. said. More than half of the infections occurred in Texas and Florida, where the climate is warm and water activities are popular. © 2022 The New York Times Company

Keyword: Miscellaneous
Link ID: 28437 - Posted: 08.20.2022

Bill Chappell Its name alone is terrifying. Add the fact that it kills most people it infects — and that while infections are rare, the parasite is fairly common — it's not surprising that a confirmed case of Naegleria fowleri infection in a swimmer in Iowa is drawing attention. Iowa officials closed the beach at Lake of Three Fires State Park on Thursday after confirming that a person who swam there was infected with Naegleria fowleri, an amoeba that causes a disease called primary amebic meningoencephalitis (PAM). It's both extremely rare — and extremely deadly. "The fatality rate is over 97%," the Centers for Disease Control and Prevention says of PAM infections. "Only four people out of 154 known infected individuals in the United States from 1962 to 2021 have survived." Details about the Iowa case have not yet been released. The person was visiting from Missouri, which is just over the border from the park in Iowa's southwest. Iowa's Department of Health and Human Services says it's working with the CDC to confirm whether Naegleria fowleri is present in the lake — a process that takes several days. The state agency is also in contact with the Missouri Department of Health, an Iowa representative told NPR. "It's strongly believed by public health experts that the lake is a likely source," Missouri's health department said on Friday. But it added, "Additional public water sources in Missouri are being tested." © 2022 npr

Keyword: Miscellaneous
Link ID: 28392 - Posted: 07.12.2022

By David Grimm In an unprecedented move, members of a confidential group that oversees animal research at the University of Washington (UW) have sued their own school to block the release of their names to an animal rights organization. People for the Ethical Treatment of Animals (PETA) has been trying to obtain this information for more than a year, charging that the makeup of the university’s Institutional Animal Care and Use Committee (IACUC) violates federal law. But the committee’s members—citing an uptick in animal rights activism at the school, including protests at the homes of individual scientists—say they fear PETA and other animal rights organizations will use their names to target them. “Animal rights groups have created a climate of fear at the university,” says the school’s IACUC chair, Jane Sullivan, who spearheaded the lawsuit. “I’m a huge fan of openness and transparency, but not when it threatens the safety of the members of my committee.” She and others fear PETA’s move is the beginning of a nationwide effort: The advocacy group also wants to name IACUC members at the University of Massachusetts (UMass) Amherst. Kathy Guillermo, a senior vice president at PETA, says her organization just wants UW's committee to comply with the law. “The IACUC is the last line of defense for animals in laboratories,” she says. But PETA suspects the university’s committee is so biased toward research interests that it’s not fulfilling its federal mandate. “The IACUC members’ supposed fear of releasing their names would appear to be more about hiding a flawed process than anything else.” Every U.S. institution that receives federal money for animal research must have an IACUC with five or more members, including scientists, veterinarians, and at least one nonscientist and one person unaffiliated with the institution. That makeup is supposed to ensure that animals are properly cared for and only necessary experiments take place, according to the U.S. National Institute of Health’s Office of Laboratory Animal Welfare (OLAW), which oversees these committees. Nonscientists can include ethicists and clergy members. © 2022 American Association for the Advancement of Science.

Keyword: Animal Rights
Link ID: 28238 - Posted: 03.16.2022

Iris Berent How can a cellist play like an angel? Why am I engrossed in my book when others struggle with reading? And while we’re at it, can you tell me why my child won’t stop screaming? Now neuroscience offers the answers—or so say the news headlines. The brains of musicians “really do” differ from those of the rest of us. People with dyslexia have different neural connections than people without the condition. And your screaming toddler’s tantrums originate from her amygdala, a brain region linked to emotions. It’s all in the brain! Neuroscience is fascinating. But it is not just the love of science that kindles our interest in these stories. Few of us care for the technical details of how molecules and electrical charges inthe brain give rise to our mental life. Furthermore, invoking the brain does not always improve our understanding. You hardly need a brain scan to tell that your toddler is enraged. Nor is it surprising that an amateur cellist’s brain works differently than Yo-Yo Ma’s—or that the brains of typical and dyslexic readers differ in some way. Where else would those differences reside? These sorts of science news stories speak to a bias: As numerous experiments have demonstrated, we have a blind spot for the brain. In classic work on the “seductive allure of neuroscience,” a team of researchers at Yale University presented participants with a psychological phenomenon (for instance, children learning new words), along with two explanations. One invoked a psychological mechanism, and the other was identical except it also dropped in a mention of a brain region. The brain details were entirely superfluous—they did nothing to improve the explanation, as judged by neuroscientists. Yet laypeople thought they did, so much so that once the brain was invoked, participants overlooked gross logical flaws in the accounts. © 2021 Scientific American,

Keyword: Attention
Link ID: 28105 - Posted: 12.11.2021

Monique Brouillette Last summer a group of Harvard University neuroscientists and Google engineers released the first wiring diagram of a piece of the human brain. The tissue, about the size of a pinhead, had been preserved, stained with heavy metals, cut into 5,000 slices and imaged under an electron microscope. This cubic millimeter of tissue accounts for only one-millionth of the entire human brain. Yet the vast trove of data depicting it comprises 1.4 petabytes’ worth of brightly colored microscopy images of nerve cells, blood vessels and more. “It is like discovering a new continent,” said Jeff Lichtman of Harvard, the senior author of the paper that presented these results. He described a menagerie of puzzling features that his team had already spotted in the human tissue, including new types of cells never seen in other animals, such as neurons with axons that curl up and spiral atop each other and neurons with two axons instead of one. These findings just scratched the surface: To search the sample completely, he said, would be a task akin to driving every road in North America. Lichtman has spent his career creating and contemplating these kinds of neural wiring diagrams, or connectomes — comprehensive maps of all the neural connections within a part or the entirety of a living brain. Because a connectome underpins all the neural activity associated with a volume of brain matter, it is a key to understanding how its host thinks, feels, moves, remembers, perceives, and much more. Don’t expect a complete wiring diagram for a human brain anytime soon, however, because it’s technically infeasible: Lichtman points out that the zettabyte of data involved would be equivalent to a significant chunk of the entire world’s stored content today. In fact, the only species for which there is yet a comprehensive connectome is Caenorhabditis elegans, the humble roundworm. Nevertheless, the masses of connectome data that scientists have amassed from worms, flies, mice and humans are already having a potent effect on neuroscience. And because techniques for mapping brains are getting faster, Lichtman and other researchers are excited that large-scale connectomics — mapping and comparing the brains of many individuals of a species — is finally becoming a reality. Share this article Simons Foundation All Rights Reserved © 2021

Keyword: Brain imaging
Link ID: 28104 - Posted: 12.08.2021

By Jillian Kramer Mice are at their best at night. But a new analysis suggests researchers often test the nocturnal creatures during the day—which could alter results and create variability across studies—if they record time-of-day information at all. Of the 200 papers examined in the new study, more than half either failed to report the timing of behavioral testing or did so ambiguously. Only 20 percent reported nighttime testing. The analysis was published in Neuroscience & Biobehavioral Reviews. West Virginia University neuroscientist Randy Nelson, the study's lead author, says this is likely a matter of human convenience. “It is easier to get students and techs to work during the day than [at] night,” Nelson says. But that convenience comes at a cost. “Time of day not only impacts the intensity of many variables, including locomotor activity, aggressive behavior, and plasma hormone levels,” but changes in those variables can only be observed during certain parts of the diurnal cycle, says University of Wyoming behavioral neuroscientist William D. Todd. This means that “failing to report time of day of data collection and tests makes interpretation of results extremely difficult,” adds Beth Israel Deaconess Medical Center staff scientist Natalia Machado. Neither Todd nor Machado was involved in the new study. The study researchers say it is critical that scientists report the timing of their work and consider the fact that animals' behavioral and physiological responses can vary with the hour. As a first step, Nelson says, “taking care of time-of-day considerations seems like low-hanging fruit in terms of increasing behavioral neuroscience research reliability, reproducibility and rigor.” © 2021 Scientific American

Keyword: Biological Rhythms
Link ID: 27953 - Posted: 08.21.2021

By Laura Sanders A brush with death led Hans Berger to invent a machine that could eavesdrop on the brain. In 1893, when he was 19, Berger fell off his horse during maneuvers training with the German military and was nearly trampled. On that same day, his sister, far away, got a bad feeling about Hans. She talked her father into sending a telegram asking if everything was all right. To young Berger, this eerie timing was no coincidence: It was a case of “spontaneous telepathy,” he later wrote. Hans was convinced that he had transmitted his thoughts of mortal fear to his sister — somehow. So he decided to study psychiatry, beginning a quest to uncover how thoughts could travel between people. Chasing after a scientific basis for telepathy was a dead end, of course. But in the attempt, Berger ended up making a key contribution to modern medicine and science: He invented the electroencephalogram, or EEG, a device that could read the brain’s electrical activity. Berger’s machine, first used successfully in 1924, produced a readout of squiggles that represented the electricity created by collections of firing nerve cells in the brain. © Society for Science & the Public 2000–2021.

Keyword: Sleep
Link ID: 27895 - Posted: 07.08.2021

By Judith Warner Dr. Benjamin Rush, the 18th-century doctor who is often called the “father” of American psychiatry, held the racist belief that Black skin was the result of a mild form of leprosy. He called the condition “negritude.” His onetime apprentice, Dr. Samuel Cartwright, spread the falsehood throughout the antebellum South that enslaved people who experienced an unyielding desire to be free were in the grip of a mental illness he called “drapetomania,” or “the disease causing Negroes to run away.” In the late 20th century, psychiatry’s rank and file became a receptive audience for drug makers who were willing to tap into racist fears about urban crime and social unrest. (“Assaultive and belligerent?” read an ad that featured a Black man with a raised fist that appeared in the “Archives of General Psychiatry” in 1974. “Cooperation often begins with Haldol.”) Now the American Psychiatric Association, which featured Rush’s image on its logo until 2015, is confronting that painful history and trying to make amends. In January, the 176-year-old group issued its first-ever apology for its racist past. Acknowledging “appalling past actions” on the part of the profession, its governing board committed the association to “identifying, understanding, and rectifying our past injustices,” and pledged to institute “anti-racist practices” aimed at ending the inequities of the past in care, research, education and leadership. This weekend, the A.P.A. is devoting its annual meeting to the theme of equity. Over the course of the three-day virtual gathering of as many as 10,000 participants, the group will present the results of its yearlong effort to educate its 37,000 mostly white members about the psychologically toxic effects of racism, both in their profession and in the lives of their patients. © 2021 The New York Times Company

Keyword: Schizophrenia; Depression
Link ID: 27797 - Posted: 05.01.2021

By Sui-Lee Wee Mark Lewis was desperate to find monkeys. Millions of human lives, all over the world, were at stake. Mr. Lewis, the chief executive of Bioqual, was responsible for providing lab monkeys to pharmaceutical companies like Moderna and Johnson & Johnson, which needed the animals to develop their Covid-19 vaccines. But as the coronavirus swept across the United States last year, there were few of the specially bred monkeys to be found anywhere in the world. Unable to furnish scientists with monkeys, which can cost more than $10,000 each, about a dozen companies were left scrambling for research animals at the height of the pandemic. “We lost work because we couldn’t supply the animals in the time frame,” Mr. Lewis said. The world needs monkeys, whose DNA closely resembles that of humans, to develop Covid-19 vaccines. But a global shortage, resulting from the unexpected demand caused by the pandemic, has been exacerbated by a recent ban on the sale of wildlife from China, the leading supplier of the lab animals. The latest shortage has revived talk about creating a strategic monkey reserve in the United States, an emergency stockpile similar to those maintained by the government for oil and grain. As new variants of the coronavirus threaten to make the current batch of vaccines obsolete, scientists are racing to find new sources of monkeys, and the United States is reassessing its reliance on China, a rival with its own biotech ambitions. The pandemic has underscored how much China controls the supply of lifesaving goods, including masks and drugs, that the United States needs in a crisis. American scientists have searched private and government-funded facilities in Southeast Asia as well as Mauritius, a tiny island nation off southeast Africa, for stocks of their preferred test subjects, rhesus macaques and cynomolgus macaques, also known as long-tailed macaques. But no country can make up for what China previously supplied. Before the pandemic, China provided over 60 percent of the 33,818 primates, mostly cynomolgus macaques, imported into the United States in 2019, according to analyst estimates based on data from the Centers for Disease Control and Prevention. © 2021 The New York Times Company

Keyword: Animal Rights
Link ID: 27703 - Posted: 02.23.2021

By Sundas Hashmi It was the afternoon of Jan. 31. I was preparing for a dinner party and adding final touches to my cheese platter when everything suddenly went dark. I woke up feeling baffled in a hospital bed. My husband filled me in: Apparently, I had suffered a massive seizure a few hours before our guests were to arrive at our Manhattan apartment. Our children’s nanny found me and I was rushed to the hospital. That had been three days earlier. My husband and I were both mystified: I was 37 years old and had always been in excellent health. In due course, a surgeon dropped by and told me I had a glioma, a type of brain tumor. It was relatively huge but operable. I felt sick to my stomach. Two weeks later, I was getting wheeled to the operating theater. I wouldn’t know the pathology until much later. I said my goodbyes to everyone — most importantly to my children, Sofia, 6, and Nyle, 2 — and prepared to die. But right before the surgery, in a very drugged state, I asked the surgeon to please get photos of me and my brother from my husband. I wanted the surgeon to see them. My brother had died two decades earlier from a different kind of brain tumor — a glioblastoma. I was 15 at the time, and he was 18. He died within two years of being diagnosed. Those two years were the worst period of my life. Doctors in my home country of Pakistan refused to take him, saying his case was fatal. So, my parents gathered their savings and flew him to Britain, where he was able to get a biopsy (his tumor was in an inoperable location) and radiation. Afterward, we had to ask people for donations so he could get the gamma knife treatment in Singapore that my parents felt confident would save him. In the end, nothing worked, and he died, taking 18 years of memories with him. © 2020 The New York Times Company

Keyword: Glia
Link ID: 27536 - Posted: 10.21.2020

Keith A. Trujillo1, Alfredo Quiñones-Hinojosa2, Kenira J. Thompson3 Joe Louis Martinez Jr. died on 29 August at the age of 76. In addition to making extraordinary contributions to the fields of neurobiology and Chicano psychology, Joe was a tireless advocate of diversity, equity, and inclusion in the sciences. He established professional development programs for individuals from underrepresented groups and provided lifelong mentoring as they pursued careers in science and academia. Joe was passionately devoted to expanding opportunities in the sciences well before diversity became a visible goal for scientific organizations and academic institutions. Born in Albuquerque, New Mexico, on 1 August 1944, Joe received his bachelor's degree in psychology from the University of San Diego in 1966; his master's in experimental psychology from New Mexico Highlands University in 1968; and his Ph.D. in physiological psychology from the University of Delaware in 1971. His faculty career began in 1972 at California State University, San Bernardino (CSUSB), shortly after the campus was established. He later completed postdocs in the laboratory of neurobiologist James McGaugh at the University of California, Irvine, and with neurobiologist Floyd Bloom at the Salk Institute for Biological Studies in San Diego, California. The University of California, Berkeley, recruited Joe in 1982, and he served as a professor as well as the area head of biopsychology and faculty assistant to the vice chancellor for affirmative action. As the highest-ranking Hispanic faculty member in the University of California system, Joe used his voice to help others from underrepresented groups. However, he felt that he could have a greater impact on diversity in the sciences by helping to build a university with a high concentration of Hispanic students, so in 1995 he moved to the University of Texas, San Antonio (UTSA). He began as a professor of biology and went on to assume a range of leadership roles, including director of the Cajal Neuroscience Institute. At UTSA, he worked with colleagues to obtain nearly $18 million in funding for neuroscience research and education. In 2012, he moved to the University of Illinois at Chicago where he served as professor and psychology department head until his retirement in 2016. At each institution, he embraced the opportunity to provide guidance and mentoring to innumerable students, faculty, and staff. © 2020 American Association for the Advancement of Science.

Keyword: Learning & Memory
Link ID: 27523 - Posted: 10.16.2020

By James Gorman Montessa, a 46-year-old chimpanzee, has been through a lot. The first record of her life is the note that she was purchased from an importer in 1975 for the research colony in New Mexico at the Holloman Air Force Base, when she was about a year old. She’s still there. It’s now called the Alamogordo Primate Facility, and Montessa, who was probably born in the wild and captured for sale, is just one of 39 chimpanzees living in limbo there, all of them the property of the National Institutes of Health. Over the past 45 years, Montessa has been pregnant five times and given birth four times. Publicly available records don’t show much about what kind of experiments were performed on her, but she was involved in a hormone study one year, and in two other years underwent a number of liver biopsies. When Dr. Francis Collins, the director of the N.I.H., decided in 2015 that all federally owned chimps would be permanently retired from research, it seemed that Montessa might get a chance to wander around on the grass at Chimp Haven in Louisiana, the designated and substantially N.I.H.-supported sanctuary. No such luck. The retirement plan had one caveat: Any chimpanzees considered too frail to be moved because of age, illness or both would stay at Alamogordo. They would no longer be subject to experiments, they were supposed to be housed in groups of seven or more, and they would have access to outdoor space and behavioral stimulation (toys, for example). But a year ago, the N.I.H. decided that Montessa and 38 other chimpanzees could not move to Chimp Haven, relying on Alamogordo staff recommendations that the chimps, many with diabetes or heart disease, would suffer and might even die if they were transferred to the sanctuary. © 2020 The New York Times Company

Keyword: Animal Rights
Link ID: 27507 - Posted: 10.07.2020

Paulina Villegas Texas Gov. Greg Abbott issued a disaster declaration in Brazoria County on Sunday after the discovery in the local water supply system of an amoeba that can cause a rare and deadly infection of the brain. “The state of Texas is taking swift action to respond to the situation and support the communities whose water systems have been impacted by this ameba,” Abbott (R) in a news release Sunday. “I urge Texans in Lake Jackson to follow the guidance of local officials and take the appropriate precautions to protect their health and safety as we work to restore safe tap water in the community.” The governor’s declaration follows an investigation of the death of 6-year-old Josiah McIntyre in Lake Jackson this month after he contracted the brain-eating microbe, which prompted local authorities and experts from the Centers for Disease Control and Prevention to test the water. The preliminary results came back Friday, showing that three out of 11 samples collected tested positive. One of the samples came from a hose bib at the boy’s home, Lake Jackson City Manager Modesto Mundo said, according to CBS News. The others came from a “splash pad” play fountain and a hydrant. “The notification to us at that time was that he had played at one of [the] play fountains and he may have also played with a water hose at the home,” Mundo said. On Friday night, the Brazosport Water Authority issued a do-not-use advisory for eight communities after confirmation of the presence of Naegleria fowleri, which destroys brain tissue, then causes swelling of the brain, known as amebic meningoencephalitis. It urged residents to not use the tap water for drinking and cooking. © 1996-2020 The Washington Post

Keyword: Miscellaneous
Link ID: 27499 - Posted: 09.30.2020

Jon Hamilton Mental illness can run in families. And Dr. Kafui Dzirasa grew up in one of these families. His close relatives include people with schizophrenia, bipolar disorder and depression. As a medical student, he learned about the ones who'd been committed to psychiatric hospitals or who "went missing" and were discovered in alleyways. Dzirasa decided to dedicate his career to "figuring out how to make science relevant to ultimately help my own family." He became a psychiatrist and researcher at Duke University and began to study the links between genes and brain disorders. Then Dzirasa realized something: "I was studying genes that were specifically related to illness in folks of European ancestry." His family had migrated from West Africa, which meant anything he discovered might not apply to them. Dzirasa also realized that people with his ancestry were missing not only from genetics research but from the entire field of brain science. "It was a really crushing moment for me," he says. So when a group in Baltimore asked Dzirasa to help do something about the problem, he said yes. The group is the African Ancestry Neuroscience Research Initiative. It's a partnership between community leaders and the Lieber Institute for Brain Development, an independent, nonprofit research organization on the medical campus of Johns Hopkins University. © 2020 npr

Keyword: Attention
Link ID: 27491 - Posted: 09.28.2020

For Armin Raznahan, publishing research on sex differences is a fraught proposition. Now chief of the section on developmental neurogenomics at the National Institutes of Health, Raznahan learned early that searching for dissimilarities between men’s and women’s brains can have unintended effects. “I got my fingers burned when I first started,” Raznahan says. As a PhD student, he published a study that examined structural differences between men’s and women’s brains and how they changed with age. “We observed a particular pattern, and we were very cautious about just describing it, as one should be, not jumping to functional interpretations,” he says. Despite his efforts, The Wall Street Journal soon published an article that cited his study in a defense of single-sex schooling, under the assumption that boys and girls must learn in distinct ways because their brain anatomy is slightly different. “That really threw me,” he says. “The experience has stayed with me.” Nevertheless, Raznahan has continued to study sex differences, in the hope that they could help us better understand neurodevelopmental disorders. He focuses on people with sex chromosome aneuploidy, or any variation other than XX (typically female) and XY (typically male). People with genetic variations (such as XXY) have an inflated risk of autism spectrum disorder, ADHD, and anxiety, among other ailments. Raznahan’s hope is that uncovering if and how men’s and women’s brains differ—for example, in the sizes of regions or the strengths of the connections among them—could help us figure out why people with aneuploidy are more likely to experience neurodevelopmental and psychiatric concerns. Solving this puzzle could be a step toward unlocking the perplexing mystery of psychiatric illness. © 2020 Condé Nast

Keyword: Sexual Behavior; Brain imaging
Link ID: 27451 - Posted: 09.05.2020

By Moises Velasquez-Manoff Jack Gallant never set out to create a mind-reading machine. His focus was more prosaic. A computational neuroscientist at the University of California, Berkeley, Dr. Gallant worked for years to improve our understanding of how brains encode information — what regions become active, for example, when a person sees a plane or an apple or a dog — and how that activity represents the object being viewed. By the late 2000s, scientists could determine what kind of thing a person might be looking at from the way the brain lit up — a human face, say, or a cat. But Dr. Gallant and his colleagues went further. They figured out how to use machine learning to decipher not just the class of thing, but which exact image a subject was viewing. (Which photo of a cat, out of three options, for instance.) One day, Dr. Gallant and his postdocs got to talking. In the same way that you can turn a speaker into a microphone by hooking it up backward, they wondered if they could reverse engineer the algorithm they’d developed so they could visualize, solely from brain activity, what a person was seeing. The first phase of the project was to train the AI. For hours, Dr. Gallant and his colleagues showed volunteers in fMRI machines movie clips. By matching patterns of brain activation prompted by the moving images, the AI built a model of how the volunteers’ visual cortex, which parses information from the eyes, worked. Then came the next phase: translation. As they showed the volunteers movie clips, they asked the model what, given everything it now knew about their brains, it thought they might be looking at. The experiment focused just on a subsection of the visual cortex. It didn’t capture what was happening elsewhere in the brain — how a person might feel about what she was seeing, for example, or what she might be fantasizing about as she watched. The endeavor was, in Dr. Gallant’s words, a primitive proof of concept. And yet the results, published in 2011, are remarkable. The reconstructed images move with a dreamlike fluidity. In their imperfection, they evoke expressionist art. (And a few reconstructed images seem downright wrong.) But where they succeed, they represent an astonishing achievement: a machine translating patterns of brain activity into a moving image understandable by other people — a machine that can read the brain. © 2020 The New York Times Company

Keyword: Vision; Brain imaging
Link ID: 27448 - Posted: 09.02.2020

When it comes to brain cells, one size does not fit all. Neurons come in a wide variety of shapes, sizes, and contain different types of brain chemicals. But how did they get that way? A new study in Nature suggests that the identities of all the neurons in a worm are linked to unique members of a single gene family that control the process of converting DNA instructions into proteins, known as gene expression. The results of this study could provide a foundation for understanding how nervous systems have evolved in many other animals, including humans. The study was funded by the National Institute of Neurological Disorders and Stroke (NINDS), part of the National Institutes of Health. “The central nervous systems of all animals, from worms to humans, are incredibly intricate and highly ordered. The generation and diversity of a plethora of neuronal cell types is driven by gene expression,” said Robert Riddle, Ph.D., program director at NINDS. “So, it is surprising and exciting to consider that the cell diversity we see in the entire nervous system could come from a just a single group of genes.” Researchers led by Oliver Hobert, Ph.D., professor of biochemistry and molecular biophysics at Columbia University in New York City and graduate student Molly B. Reilly, wanted to know how brain cells in the C. elegans worm got their various shapes and functions. For these experiments, the researchers used a genetically engineered worm in which individual neurons were color coded. In addition, coding sequences for green fluorescence protein were inserted into homeobox genes, a highly conserved set of genes known to play fundamental roles in development. Homeobox gene expression patterns were determined by examining the patterns of the glowing fluorescent marker.

Keyword: Development of the Brain; Brain imaging
Link ID: 27428 - Posted: 08.20.2020

By Abdul-Kareem Ahmed “He doesn’t look like himself,” his wife said. It was midnight, and I was consulting on a patient in the emergency room. He was 48 years old and complaining of a headache. Ten years ago my attending had partially removed a benign tumor growing in his cerebellum, part of the hindbrain that controls movement, coordination and speech. Our team had also placed a shunt in his brain. The brain is buoyed and bathed by cerebrospinal fluid. This clear fluid is made in large cavities, called ventricles, and is eventually absorbed by veins. The tumor’s inoperable remnant had blocked the fluid’s natural escape, causing it to build up, a condition known as hydrocephalus. A shunt is a thin rubber tube that is placed in the ventricles of the brain and tunneled under the skin, into the abdomen. It can have a programmable pressure valve, a gauge that sits under the scalp. His shunt had been siphoning excess fluid to his abdomen for years where it was absorbed, preventing life-threatening high pressure in the brain. Today, however, something was wrong, and I thought it was revealed on his new head CT. His ventricles were very large, suggesting high pressure. “I get a bad headache when I sit up,” he mumbled. “Sometimes I vomit. I feel better when I lie flat.” His wife, a strong and kindhearted woman, corroborated his complaint. “He’s also having memory problems, and he’s losing his balance when he walks,” she added. His symptoms were the opposite of what I expected. He was describing a low-pressure headache. He was relieved by lying down but worsened when sitting up.

Keyword: Pain & Touch
Link ID: 27397 - Posted: 08.03.2020