Chapter 7. Life-Span Development of the Brain and Behavior

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Davide Castelvecchi The wrinkles that give the human brain its familiar walnut-like appearance have a large effect on brain activity, in much the same way that the shape of a bell determines the quality of its sound, a study suggests1. The findings run counter to a commonly held theory about which aspect of brain anatomy drives function. The study’s authors compared the influence of two components of the brain’s physical structure: the outer folds of the cerebral cortex — the area where most higher-level brain activity occurs — and the connectome, the web of nerves that links distinct regions of the cerebral cortex. The team found that the shape of the outer surface was a better predictor of brainwave data than was the connectome, contrary to the paradigm that the connectome has the dominant role in driving brain activity. “We use concepts from physics and engineering to study how anatomy determines function,” says study co-author James Pang, a physicist at Monash University in Melbourne, Australia. The results were published in Nature on 31 May1. ‘Exciting’ a neuron makes it fire, which sends a message zipping to other neurons. Excited neurons in the cerebral cortex can communicate their state of excitation to their immediate neighbours on the surface. But each neuron also has a long filament called an axon that connects it to a faraway region within or beyond the cortex, allowing neurons to send excitatory messages to distant brain cells. In the past two decades, neuroscientists have painstakingly mapped this web of connections — the connectome — in a raft of organisms, including humans. The authors wanted to understand how brain activity is affected by each of the ways in which neuronal excitation can spread: across the brain’s surface or through distant interconnections. To do so, the researchers — who have backgrounds in physics and neuroscience — tapped into the mathematical theory of waves.

Keyword: Brain imaging; Development of the Brain
Link ID: 28811 - Posted: 06.03.2023

By Robert Martone Neurological conditions can release a torrent of new creativity in a few people as if opening some mysterious floodgate. Auras of migraine and epilepsy may have influenced a long list of artists, including Pablo Picasso, Vincent van Gogh, Edvard Munch, Giorgio de Chirico, Claude Monet and Georges Seurat. Traumatic brain injury (TBI) can result in original thinking and newfound artistic drive. Emergent creativity is also a rare feature of Parkinson’s disease. But this burst of creative ability is especially true of frontotemporal dementia (FTD). Although a few rare cases of FTD are linked to improvements in verbal creativity, such as greater poetic gifts and increased wordplay and punning, enhanced creativity in the visual arts is an especially notable feature of the condition. Fascinatingly, this burst of creativity indicates that the potential to create may rest dormant in some of us, only to be unleashed by a disease that also causes a loss of verbal abilities. The emergence of a vibrant creative spark in the face of devastating neurological disease speaks to the human brain’s remarkable potential and resilience. A new study published in JAMA Neurology examines the roots of this phenomenon and provides insight into a possible cause. As specific brain areas diminish in FTD, the researchers find, they release their inhibition, or control, of other regions that support artistic expression. Frontotemporal dementia is relatively rare—affecting about 60,000 people in the U. S.—and distinct from the far more common Alzheimer’s disease, a form of dementia in which memory deficits predominate. FTD is named for the two brain regions that can degenerate in this disease, specifically the frontal and temporal lobes.

Keyword: Alzheimers; Attention
Link ID: 28797 - Posted: 05.27.2023

By Jennie Erin Smith José Echeverría spends restless days in a metal chair reinforced with boards and padded with a piece of foam that his mother, Nohora Vásquez, adjusts constantly for his comfort. The chair is coming loose and will soon fall apart. Huntington’s disease, which causes José to move his head and limbs uncontrollably, has already left one bed frame destroyed. At 42, he is still strong. José’s sister Nohora Esther Echeverría, 37, lives with her mother and brother. Just two years into her illness, her symptoms are milder than his, but she is afraid to walk around her town’s steep streets, knowing she could fall. A sign on the front door advertises rum for sale that does not exist. The family’s scarce resources now go to food — José and Nohora Esther must eat frequently or they will rapidly lose weight — and medical supplies, like a costly cream for Jose’s skin. Huntington’s is a hereditary neurodegenerative disease caused by excess repetitions of three building blocks of DNA — cytosine, adenine, and guanine — on a gene called huntingtin. The mutation results in a toxic version of a key brain protein, and a person’s age at the onset of symptoms relates, roughly, to the number of repetitions the person carries. Early symptoms can include mood disturbances — Ms. Vásquez remembers how her late husband had chased the children out of their beds, forcing her to sleep with them in the woods — and subtle involuntary movements, like the rotations of Nohora Esther’s delicate wrists. The disease is relatively rare, but in the late 1980s a Colombian neurologist, Jorge Daza, began observing a striking number of cases in the region where Ms. Vásquez lives, a cluster of seaside and mountain towns near Barranquilla. Around the same time, American scientists led by Nancy Wexler were working with an even larger family with Huntington’s in neighboring Venezuela, gathering and studying thousands of tissue samples from them to identify the genetic mutation responsible. © 2023 The New York Times Company

Keyword: Huntingtons; Genes & Behavior
Link ID: 28796 - Posted: 05.23.2023

Sara Reardon Researchers have identified a man with a rare genetic mutation that protected him from developing dementia at an early age. The finding, published on 15 May in Nature Medicine1, could help researchers to better understand the causes of Alzheimer’s disease and potentially lead to new treatments. For nearly 40 years, neurologist Francisco Lopera at the University of Antioquia in Medellín, Colombia, has been following an extended family whose members develop Alzheimer’s in their forties or earlier. Many of the approximately 6,000 family members carry a genetic variant called the paisa mutation that inevitably leads to early-onset dementia. But now, Lopera and his collaborators have identified a family member with a second genetic mutation — one that protected him from dementia until age 67. “Reading that paper made the hair on my arms stand up,” says neuroscientist Catherine Kaczorowski at the University of Michigan in Ann Arbor. “It’s just such an important new avenue to pursue new therapies for Alzheimer’s disease.” Lopera and his colleagues analysed the genomes and medical histories of 1,200 Colombians with the paisa mutation, which causes dementia around ages 45—50. They identified the man with the second mutation when he was 67 and had only mild cognitive impairment. When the researchers scanned his brain, they found high levels of the sticky protein complexes known as amyloid plaques, which are thought to kill neurons and cause dementia, as well as a protein called tau that accumulates as the disease progresses. The brain looked like that of a person with severe dementia, says study co-author Joseph Arboleda, an ophthalmologist at Harvard Medical School in Boston, Massachusetts. But a small brain area called the entorhinal cortex, which coordinates skills such as memory and navigation, had low levels of tau. © 2023 Springer Nature Limited

Keyword: Alzheimers; Genes & Behavior
Link ID: 28786 - Posted: 05.18.2023

By Cordula Hölig, Brigitte Röder, Ramesh Kekunnaya Growing up in poverty or experiencing any adversity, such as abuse or neglect, during early childhood can put a person at risk for poor health, including mental disorders, later in life. Although the underlying mechanisms are poorly understood, some studies have shown that adverse early childhood experience leaves persisting (and possibly irreversible) traces in brain structure. As neuroscientists who are investigating sensitive periods of human brain development, we agree: safe and nurturing environments are a prerequisite for healthy brain development and lifelong well-being. Thus, preventing early childhood adversity undoubtedly leads to healthier lives. Poverty and adversity can cause changes in brain development. Harms can come from exposure to violence or toxins or a lack of nutrition, caregiving, perceptual and cognitive stimulation or language interaction. Neuroscientists have demonstrated that these factors crucially influence human brain development. Advertisement We don’t know whether these changes are reversed by more favorable circumstances later in life, however. Investigating this question in humans is extremely difficult. For one, multiple biological and psychological factors through which poverty and adversity affect brain development are hard to disentangle. That’s because they often occur together: a neglected child often experiences a lack of caregiving simultaneously with malnutrition and exposure to physical violence. Secondly, a clear beginning and end of an adverse experience is hard to define. Finally, it is almost impossible to fully reverse harsh environments in natural settings because most of the time it is impossible to move children out of their families or communities.. © 2023 Scientific American

Keyword: Development of the Brain; Learning & Memory
Link ID: 28783 - Posted: 05.13.2023

Scientists at the National Institutes of Health have identified new genetic risk factors for two types of non-Alzheimer’s dementia. These findings were published in Cell Genomics and detail how researchers identified large-scale DNA changes, known as structural variants, by analyzing thousands of DNA samples. The team discovered several structural variants that could be risk factors Lewy body dementia (LBD) and frontotemporal dementia (FTD). The project was a collaborative effort between scientists at the National Institute of Neurological Disorders and Stroke (NINDS) and the National Institute on Aging (NIA) at NIH. Structural variants have been implicated in a variety of neurological disorders. Unlike more commonly studied mutations, which often affect one or a few DNA building blocks called nucleotides, structural variants represent at least 50 but often hundreds, or even thousands, of nucleotides at once, making them more challenging to study. “If you imagine that our entire genetic code is a book, a structural variant would be a paragraph, page, or even an entire chapter that has been removed, duplicated, or inserted in the wrong place,” said Sonja W. Scholz, M.D., Ph.D., investigator in the neurogenetics branch of NINDS and senior author of this study. By combining cutting-edge computer algorithms capable of mapping structural variations across the whole genome with machine learning, the research team analyzed whole-genome data from thousands of patient samples and several thousand unaffected controls. A previously unknown variant in the gene TCPN1 was found in samples from patients with LBD, a disease, that like Parkinson’s disease, is associated with abnormal deposits of the protein alpha-synuclein in the brain. This variant, in which more than 300 nucleotides are deleted from the gene, is associated with a higher risk for developing LBD. While this finding is new for LBD, TCPN1 is a known risk factor for Alzheimer’s disease, which could mean that this structural variant plays a role in the broader dementia population.

Keyword: Alzheimers; Genes & Behavior
Link ID: 28775 - Posted: 05.10.2023

Sara Reardon For the second time, an experimental drug has been shown to reduce the cognitive decline associated with Alzheimer’s disease. On 3 May, pharmaceutical company Eli Lilly announced in a press release that its monoclonal antibody donanemab slowed mental decline by 35% for some participants in a 1,736-person trial — a rate comparable to that for competitor drug lecanemab. But researchers warn that until the full results are published, questions remain as to the drug’s clinical usefulness, as well as whether the modest benefit outweighs the risk of harmful side effects. Like lecanemab, donanemab targets amyloid protein, which is thought to cause dementia by accumulating in the brain and damaging neurons. The trial results provide strong evidence that amyloid is a key driver of Alzheimer’s, says Jeffrey Cummings, a neuroscientist at the University of Nevada, Las Vegas. “These are transformative in an enormously important way from a scientific point of view,” he adds. “They’re terrific.” But Marsel Mesulam, a neurologist at Northwestern University in Chicago, is more cautious. “The results that are described are extremely significant and impressive, but clinically their significance is doubtful,” he says, adding that the modest effect suggests that factors other than amyloid contribute to Alzheimer’s disease progression. “We’re heading to a new era — there’s room to cheer, but it’s an era that should make us all very sober, realizing that there will be no single magic bullet.” In the press release, Eli Lilly said that people with mild Alzheimer’s who received donanemab showed 35% less clinical decline over 18 months than did those who received a placebo, and 40% less decline in their ability to perform daily tasks. The company, based in Indianapolis, Indiana, says that it will present the full results at a conference in July and publish them in a peer-reviewed journal. It plans to apply for approval by the US Food and Drug Administration (FDA) in the next two months. Promising treatments © 2023 Springer Nature Limited

Keyword: Alzheimers
Link ID: 28773 - Posted: 05.06.2023

By Sofia Quaglia With a large blade resembling a bread knife—but without the jagged edges—Stephanie Forkel slices through the human brain lying in front of her on the dissection table. A first-year university student, Forkel is clad in an apron and protective gear. It’s her first day working in the morgue at a university hospital in Munich, Germany, where the brains of people who’ve donated their bodies to science are examined for research. Her contact lenses feel dry because of the dense formaldehyde hanging in the air. But that’s not the only reason she squints a little harder. When she looks down at the annotated brain diagram in the textbook she’s supposed to use for reference, the real human brain in front of her looks nothing like the illustrated one. That was Forkel’s first eureka moment: The standard reference shape of the brain and real brains were actually vastly divergent. As she continued her studies, she confirmed that, indeed, “every individual brain looked very different,” she recounts decades later. A growing body of research now confirms there are plenty of physical dissimilarities between individual brains, particularly when it comes to white matter—the material nestled beneath the much-prized gray matter. And it’s not just anatomical. White matter hosts connections between the brain’s sections, like a city’s streets and avenues. So behavioral patterns can arise from even small physical differences in white matter, according to a late 2022 Science paper penned by Forkel and a colleague.1 Forkel is now one of a host of researchers probing subtle differences in white matter to better understand the extent of its role in making us who we are—including how much white matter dictates variations between people’s everyday behavior, and whether it’s implicated in how some patients recover better than others from life-threatening brain injuries. © 2023 NautilusNext Inc.,

Keyword: Development of the Brain
Link ID: 28762 - Posted: 05.03.2023

By Jaya Padmanabhan Speaking two languages provides the enviable ability to make friends in unusual places. A new study suggests that bilingualism may also come with another benefit: improved memory in later life. Studying hundreds of older patients, researchers in Germany found that those who reported using two languages daily from a young age scored higher on tests of learning, memory, language and self-control than patients who spoke only one language. The findings, published in the April issue of the journal Neurobiology of Aging, add to two decades of work suggesting that bilingualism protects against dementia and cognitive decline in older people. “It’s promising that they report that early and middle-life bilingualism has a beneficial effect on cognitive health in later life,” said Miguel Arce Rentería, a neuropsychologist at Columbia University who was not involved in the study. “This would line up with the existing literature.” In recent years, scientists have gained a greater understanding of bilingualism and the aging brain, though not all their findings have aligned. Some have found that if people who have fluency in two languages develop dementia, they’ll develop it at a later age than people who speak one language. But other research has shown no clear benefit from bilingualism. Neuroscientists hypothesize that because bilingual people switch fluidly between two languages, they may be able to deploy similar strategies in other skills — such as multitasking, managing emotions and self-control — that help delay dementia later on. The new study tested 746 people age 59 to 76. Roughly 40 percent of the volunteers had no memory problems, while the others were patients at memory clinics and had experienced confusion or memory loss. © 2023 The New York Times Company

Keyword: Alzheimers; Language
Link ID: 28761 - Posted: 04.29.2023

Nicola Davis Science correspondent From loud snores to twitching paws, dogs often appear to have a penchant for a good snooze. But researchers have said elderly canines with dementia appear to spend less time slumbering than those with healthy brains – mirroring patterns seen in humans. It has long been known that people with dementia can experience sleep problems, including finding it harder to get to sleep. Researchers have also found changes in the brainwaves of people with dementia during sleep – including decreased slow brain waves that occur during non-rapid eye movement deep sleep. These are important in memory consolidation and appear to be linked to the activity of the brain’s system for clearing away waste. Now it seems sleep impairment may occur in dogs experiencing a condition similar to dementia in humans. “Changes in sleep habits should be expected in older dogs, and could be a harbinger of decline in cognition,” said Prof Natasha Olby, senior author of a study at North Carolina State University. Writing in the journal Frontiers in Veterinary Science, Olby and colleagues reported on their study of 28 dogs aged between 10 and 16 years old. The canines’ brainwaves were recorded by electroencephalogram (EEG) while the dogs took a two-hour afternoon nap. The researchers also assessed owners’ answers to a questionnaire and each dog’s performance on a range of problem-solving, memory and attention tasks, to provide a score indicating whether the dog had, or was at risk of, canine dementia. Twenty of the dogs were deemed to have cognitive impairment, with this judged to be severe in eight of them. Combining their data, the team found dogs with higher dementia scores took longer to fall asleep and spent less time sleeping. © 2023 Guardian News & Media Limited

Keyword: Alzheimers; Sleep
Link ID: 28760 - Posted: 04.29.2023

By Laurie McGinley — When Rebecca Chopp was diagnosed with early-stage Alzheimer’s disease, she and her husband did the only thing that seemed to make sense: They went to their favorite Mexican restaurant, held each other in a back booth and drank margaritas. And cried. After a while, they helped each other back across the street to their home. Chopp, at 67, was chancellor of the University of Denver, at the pinnacle of a career powered by a daunting intellect and relentless work. She was also an ordained minister, prolific author and former president of Swarthmore College and Colgate University. Sometimes, Chopp thought of herself as a brain with a body attached. The changes were subtle: Chopp was sleeping more. She got lost on the way to the doctor. Then came the diagnosis. (Joanna Kulesza/For The Washington Post ) Now, she was crushed, facing the loss of that beautiful mind. She worried she would soon be an empty shell, drooling and unkempt, a burden to the people she loved. “There is a sense that when you are diagnosed, you are immediately going to descend into madness,” Chopp said. When she relinquished the job she loved, Chopp fell into deep despair, confounded by the prescription given to her by an empathetic doctor: “Live with joy!” She had nightmares about going insane. But, eventually, she began to push back against the darkness. Chopp has mild cognitive impairment, a condition that involves subtle changes in thinking and memory and that, in most cases, leads to Alzheimer’s dementia, a fatal neurodegenerative disease that affects more than 6.7 million Americans. Using diet, exercise and joy to slow Alzheimer’s For years, there was little doctors could do for people with Alzheimer’s, even at a very early stage. Now, changes are coming in how the disease is diagnosed and treated, and patients with mild cognitive impairment are at the center of the efforts. Lacking a cure, scientists are trying desperately to delay the worst phase of the illness.

Keyword: Alzheimers
Link ID: 28752 - Posted: 04.26.2023

By Emily Underwood The ability to set a goal and pursue it without getting derailed by temptations or distractions is essential to nearly everything we do in life, from finishing homework to driving safely in traffic. It also places complex demands on the brain, requiring skills like working memory — the ability to keep small amounts of information in mind to perform a task — as well as impulse control and being able to rapidly adapt when rules or circumstances change. Taken together, these elements add up to something researchers call executive function. We all struggle with executive function sometimes, for example when we’re stressed or don’t get enough sleep. But in teenagers, these powers are still a work in progress, contributing to some of the contradictory behaviors and lapses in judgment — “My honor roll student did what on TikTok?” — that baffle many parents. This erratic control can be dangerous, especially when teens make impulsive choices. But that doesn’t mean the teen brain is broken, says Beatriz Luna, a developmental cognitive neuroscientist at the University of Pittsburgh and coauthor of a review on the maturation of one aspect of executive function, called cognitive control, in the 2015 Annual Review of Neuroscience. Adolescents have all the basic neural circuitry needed for executive function and cognitive control, Luna says. In fact, they have more than they need — what’s lacking is experience, which over time will strengthen some neural pathways and weaken or eliminate others. This winnowing serves an important purpose: It tailors the brain to help teens handle the demands of their unique, ever-changing environments and to navigate situations their parents may never have encountered. Luna’s research suggests that teens’ inconsistent cognitive control is key to becoming independent, because it encourages them to seek out and learn from experiences that go beyond what they’ve been actively taught. © 2023 Annual Reviews

Keyword: Development of the Brain; Attention
Link ID: 28751 - Posted: 04.26.2023

By R. Douglas Fields Dazzling intricacies of brain structure are revealed every day, but one of the most obvious aspects of brain wiring eludes neuroscientists. The nervous system is cross-wired, so that the left side of the brain controls the right half of the body and vice versa. Every doctor relies upon this fact in performing neurological exams, but when I asked my doctor last week why this should be, all I got was a shrug. So I asked Catherine Carr, a neuroscientist at the University of Maryland, College Park. “No good answer,” she replied. I was surprised — such a fundamental aspect of how our brain and body are wired together, and no one knew why? Nothing that we know of stops the right side of the brain from connecting with the right side of the body. That wiring scheme would seem much simpler and less prone to errors. In the embryonic brain, the crossing of the wires across the midline — an imaginary line dividing the right and left halves of the body — requires a kind of molecular “traffic cop” to somehow direct the growing nerve fibers to the right spot on the opposite side of the body. Far simpler just to keep things on the same side. Yet this neural cross wiring is ubiquitous in the animal kingdom — even the neural connections in lowly nematode worms are wired with left-right reversal across the animal’s midline. And many of the traffic cop molecules that direct the growth of neurons in these worms do the same in humans. For evolution to have conserved this arrangement so doggedly, surely there’s some benefit to it, but biologists still aren’t certain what it is. An intriguing answer, however, has come from the world of mathematics. The key to that solution lies in exactly how neural circuits are laid out within brain tissue. Neurons that make connections between the brain and the body are organized to create a virtual map in the cerebral cortex. If a neuroscientist sticks an electrode into the brain and finds that neurons there receive input from the thumb, for example, then neurons next to it in the cerebral cortex will connect to the index finger. This mapping phenomenon is called somatotopy, Greek for “body mapping,” but it’s not limited to the physical body. The 3D external world we perceive through vision and our other senses is mapped onto the brain in the same way. All Rights Reserved © 2023

Keyword: Laterality; Development of the Brain
Link ID: 28749 - Posted: 04.22.2023

Jon Hamilton Boys born to mothers who got COVID-19 while pregnant appear nearly twice as likely as other boys to be diagnosed with subtle delays in brain development. That's the conclusion of a study of more than 18,000 children born at eight hospitals in Eastern Massachusetts. Nearly 900 of the children were born to mothers who had COVID during their pregnancy. In the study, boys, but not girls, were more likely to be diagnosed with a range of developmental disorders in the first 18 months of life. These included delays in speech and language, psychological development and motor function, as well as intellectual disabilities. In older children, these differences are often associated with autism spectrum disorder, says Dr. Roy Perlis, a co-author of the study and a psychiatrist at Massachusetts General Hospital. But for the young children in this study, "it's way too soon to reliably diagnose autism," Perlis says. "All we can hope to detect at this point are more subtle sorts of things like delays in language and speech, and delays in motor milestones." The study, which relied on an analysis of electronic health records, was published in March in the journal JAMA Network Open. The finding is just the latest to suggest that a range of maternal infections can alter fetal brain development, especially in male offspring. For example, studies have found links between infections like influenza and cytomegalovirus, and disorders like autism and schizophrenia. "Male fetuses are known to be more vulnerable to maternal infectious exposures during pregnancy," says Dr. Andrea Edlow, the study's lead author and a maternal-fetal medicine specialist at Massachusetts General Hospital. © 2023 npr

Keyword: Development of the Brain; Sexual Behavior
Link ID: 28743 - Posted: 04.18.2023

by Sarah DeWeerdt Many papers about autism-linked genes note that the genes are expressed throughout both the central and the peripheral nervous systems. The proportion of such prolific genes may be as high as two-thirds, according to one 2020 analysis. Yet few studies delve into what those genes are actually doing outside the brain. That’s starting to change. Although autism is typically thought of as a brain condition, a critical mass of researchers has started to investigate how the condition alters neurons elsewhere in the body. Their work — part of a broader trend in neuroscience to look beyond the brain — hints that the role of the peripheral nervous system in autism is, well, anything but peripheral: Neuronal alterations outside the brain may help to explain a host of the condition’s characteristic traits. Much of the research so far focuses on touch and the workings of the gut, but there is increasing interest in other sensory and motor neurons, as well as the autonomic nervous system, which orchestrates basic body functions such as heartbeat, blood pressure, breathing and digestion. It’s difficult to pinpoint whether some autism traits arise in the peripheral nervous system or the central nervous system; in many cases, complex feedback loops link the two. “Your nervous system doesn’t know that we’ve divided it that way,” says Carissa Cascio, associate professor of psychiatry and behavioral sciences at Vanderbilt University in Nashville, Tennessee. But at least some peripheral changes may offer novel treatment targets. And drugs that act in the peripheral nervous system could also prove more effective and have fewer side effects than brain-based therapies, says Julia Dallman, associate professor of biology at the University of Miami in Coral Gables, Florida. © 2023 Simons Foundation

Keyword: Autism
Link ID: 28739 - Posted: 04.15.2023

By Azeen Ghorayshi Morénike Giwa Onaiwu was shocked when day care providers flagged some concerning behaviors in her daughter, Legacy. The toddler was not responding to her name. She avoided eye contact, didn’t talk much and liked playing on her own. But none of this seemed unusual to Dr. Onaiwu, a consultant and writer in Houston. “I didn’t recognize anything was amiss,” she said. “My daughter was just like me.” Legacy was diagnosed with autism in 2011, just before she turned 3. Months later, at the age of 31, Dr. Onaiwu was diagnosed as well. Autism, a neurodevelopmental disorder characterized by social and communication difficulties as well as repetitive behaviors, has long been associated with boys. But over the past decade, as more doctors, teachers and parents have been on the lookout for early signs of the condition, the proportion of girls diagnosed with it has grown. In 2012, the Centers for Disease Control and Prevention estimated that boys were 4.7 times as likely as girls to receive an autism diagnosis. By 2018, the ratio had dipped to 4.2 to 1. And in data released by the agency last month, the figure was 3.8 to 1. In that new analysis, based on the health and education records of more than 226,000 8-year-olds across the country, the autism rate in girls surpassed 1 percent, the highest ever recorded. More adult women like Dr. Onaiwu are being diagnosed as well, raising questions about how many young girls continue to be missed or misdiagnosed. “I think we just are getting more aware that autism can occur in girls and more aware of the differences,” said Catherine Lord, a psychologist and autism researcher at the University of California, Los Angeles. © 2023 The New York Times Company

Keyword: Autism; Sexual Behavior
Link ID: 28737 - Posted: 04.12.2023

Alison Abbott When neurologist Reisa Sperling stepped up to receive her lifetime achievement award at an international Alzheimer’s conference last December, she was more excited about the future than about celebrating the past. What thrilled Sperling, who won the award for her work on clinical trials of Alzheimer’s treatments, was a sense of hope, which has been conspicuously missing from research into the disease for many years. Most other attendees felt the same. Just a few months before the meeting, researchers had announced that an antibody drug called lecanemab clearly lowered the amount of amyloid protein plaques — a tell-tale sign of the disease — in the brains of participants in a clinical trial, and slowed their cognitive decline. Sperling, who runs a laboratory at Harvard Medical School in Boston, Massachusetts, was buoyant as she gripped the microphone tightly. After spending more than 30 frustrating years in Alzheimer’s research, she said, there was finally proof that she and her colleagues were on the right track. “But still, it isn’t enough,” she said. In the trial, treatment led to a 25% slowing of decline, enough to give participants a few extra months of independent living1. “But actually conquering a destructive disease that affects tens of millions of people worldwide is a different story,” she says. What’s more, lecanemab, marketed in the United States as Leqembi, makes for a tough treatment regime. It has to be infused through a vein by a nursing professional. And because the drug can cause potentially life-threatening brain swelling and bleeds, people taking it have to be monitored regularly.

Keyword: Alzheimers
Link ID: 28736 - Posted: 04.12.2023

By Amber Dance Isabelle Lousada was in her early 30s when she collapsed at her Philadelphia wedding in 1995. A London architect, she had suffered a decade of mysterious symptoms: tingling fingers, swollen ankles, a belly distended by her enlarged liver. The doctors she first consulted suggested she had chronic fatigue syndrome or that she’d been partying and drinking too hard. But her new brother-in-law, a cardiologist, felt that something else must be going on. A fresh series of doctor’s visits led, finally, to the proper diagnosis: Malformed proteins had glommed together inside Lousada’s bloodstream and organs. Those giant protein globs are called amyloid, and the diagnosis was amyloidosis. Amyloid diseases that affect the brain, such as Alzheimer’s and Parkinson’s diseases, receive the lion’s share of attention from medical professionals and the press. In contrast, amyloid diseases that affect other body parts are less familiar and rarely diagnosed conditions, says Gareth Morgan, a biochemist at Boston University Chobanian & Avedisian School of Medicine. Physicians may struggle to recognize and distinguish them, especially in early stages. Treatment options have also been limited — Lousada, now CEO of the nonprofit Amyloidosis Research Consortium in Newton, Massachusetts, was fortunate to survive thanks to a stem cell transplant that is too grueling or unsuitable for many with amyloidosis. Several new medications have come out in the last five years — and these, Lousada says, “have been real game-changers.” But although these therapies can block the formation of new, damaging amyloid, they can’t dissolve the amyloid that’s already built up. The body has natural processes to do so, but these are often too slow to clear years’ worth of built-up amyloid, especially in older individuals. And so patients still deal with amyloid clogging their organs, and people still die of amyloidosis, even if they survive longer than they once did. © 2023 Annual Reviews

Keyword: Alzheimers; Parkinsons
Link ID: 28731 - Posted: 04.09.2023

Visual: Andrew Bret Wallis/The Image Bank via Getty Images By Lina Tran At 25, Dasha Kiper moved in with a 98-year-old man. She’d just left a graduate program in clinical psychology; Mr. Kessler was a Holocaust survivor in the early stages of Alzheimer’s disease, whose son had hired Kiper as a live-in caregiver. One day, Mr. Kessler clambers onto a chair to replace the battery in a smoke detector. When he ignores her instructions to come down, Kiper loses her cool. She shouts that he’s incapable of changing the battery and doing much of anything for himself. Later, Kiper is filled with remorse. She should have known better than to yell at a nonagenarian with dementia. This is the focus of Kiper’s “Travelers to Unimaginable Lands: Stories of Dementia, the Caregiver, and the Human Brain” — not the mind of the patient, but the caregiver. Often, the spouses, children, and loved ones of people living with dementia succumb to arguing or pleading with their patients, despite reason. “We want to reestablish a shared reality,” Kiper writes. “It’s not cruelty but desperation that drives us to confront them with the truth.” Caregivers aren’t mere observers to cognitive decline but the “invisible victims” of dementia disorders, Kiper writes. They traverse warped realities that operate under different rules of time and memory. One caregiver says, referring to a famous case study by neurologist and author Oliver Sacks, it’s “like being an anthropologist on Mars.” But a caregiver’s slip-up isn’t necessarily the result of character flaws or a lapse in compassion. Rather, Kiper shows the healthy brain is riddled with cognitive biases that impede the work of caring for a person with an impaired mind. This takes a heavy toll. “People always ask about the patient,” one exasperated woman tells Kiper, after recounting how her husband, who doesn’t recognize her, takes to locking her out of their apartment each night. She starts carrying a spare key to let herself in after he falls asleep. “Let me tell you something, the patient is fine; it’s the caregiver who’s going crazy.”

Keyword: Alzheimers; Stress
Link ID: 28728 - Posted: 04.09.2023

ByJennifer Couzin-Frankel A class of Alzheimer’s drugs that aims to slow cognitive decline, including the antibody lecanemab that was granted accelerated approval in the United States in January, can cause brain shrinkage, researchers report in a new analysis. Although scientists and drug developers have documented this loss of brain volume in clinical trial participants for years, the scientific review, published yesterday in Neurology, is the first to look at data across numerous studies. It also links the brain shrinkage to a better known side effect of the drugs, brain swelling, which often presents without symptoms. “We don’t fully know what these changes might imply,” says Jonathan Jackson, a cognitive neuroscientist at Massachusetts General Hospital. But, “These data are extremely concerning, and it’s likely these changes are detrimental.” The analysis, which found that trial participants taking these Alzheimer’s drugs often developed more brain shrinkage than when they were on a placebo, alarmed Scott Ayton, a neuroscientist at the Florey Institute of Neuroscience and Mental Health in Melbourne, Australia, who led the work. “We’re talking about the possibility of brain damage” from treatment, says Ayton, who was invited by Eisai to join an advisory board on lecanemab’s rollout in Australia if the drug is approved there. “I find it very peculiar that these data, which are very important, have been completely ignored by the field.” A spokesperson for Eisai suggested there are benign theories for the brain shrinkage, too. The company said that although participants in its pivotal trial did experience “greater cortical volume loss on lecanemab relative to placebo,” those reductions may be due to antibody clearing the protein beta amyloid from the brain, and reducing inflammation. © 2023 American Association for the Advancement of Science.

Keyword: Alzheimers; Brain imaging
Link ID: 28721 - Posted: 03.29.2023