Chapter 11. Motor Control and Plasticity

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By Jonathan Moens An artificial intelligence can decode words and sentences from brain activity with surprising — but still limited — accuracy. Using only a few seconds of brain activity data, the AI guesses what a person has heard. It lists the correct answer in its top 10 possibilities up to 73 percent of the time, researchers found in a preliminary study. The AI’s “performance was above what many people thought was possible at this stage,” says Giovanni Di Liberto, a computer scientist at Trinity College Dublin who was not involved in the research. Developed at the parent company of Facebook, Meta, the AI could eventually be used to help thousands of people around the world unable to communicate through speech, typing or gestures, researchers report August 25 at arXiv.org. That includes many patients in minimally conscious, locked-in or “vegetative states” — what’s now generally known as unresponsive wakefulness syndrome (SN: 2/8/19). Most existing technologies to help such patients communicate require risky brain surgeries to implant electrodes. This new approach “could provide a viable path to help patients with communication deficits … without the use of invasive methods,” says neuroscientist Jean-Rémi King, a Meta AI researcher currently at the École Normale Supérieure in Paris. King and his colleagues trained a computational tool to detect words and sentences on 56,000 hours of speech recordings from 53 languages. The tool, also known as a language model, learned how to recognize specific features of language both at a fine-grained level — think letters or syllables — and at a broader level, such as a word or sentence. © Society for Science & the Public 2000–2022.

Keyword: Language; Robotics
Link ID: 28470 - Posted: 09.10.2022

By Laurie McGinley Independent advisers to the Food and Drug Administration on Wednesday voted 7 to 2 to recommend approval of an experimental ALS drug with strong support from patients and advocates, making it likely the hotly debated treatment will be cleared by the agency within weeks. The vote was a stunning turnaround from late March when the panel voted 6 to 4 to recommend against FDA approval. At that meeting, the FDA’s Peripheral and Central Nervous System Drugs Advisory Committee concluded the evidence from a single clinical trial — with just 137 patients and some follow-up data — was not sufficient to show the drug, called AMX0035, slowed a degenerative disease that usually kills people within three to five years. But on Wednesday, after hours of discussion, several advisers said that additional analyses submitted by the drug’s manufacturer, Cambridge-based Amylyx, bolstered the case for approval, even though uncertainties remain. Advisers were also affected by the disease’s severity and the lack of effective treatments. A vow by a top Amylyx official to pull the drug from the market if a larger study, with 600 patients, fails to show effectiveness was also a factor in the vote. The FDA, which usually follows the recommendation of its outside advisers but is not required to, is expected to decide whether to approve the drug by Sept. 29. The improved fortunes of the medicine came despite criticism from FDA staff as recently as last week about the treatment’s effectiveness, the conduct of its clinical trial and the researchers’ interpretation of the data. But the medicine is considered safe, and the agency has been under intense pressure from ALS patients and physicians who say the treatment holds promise for a fatal disease that typically causes rapid deterioration and death.

Keyword: ALS-Lou Gehrig's Disease
Link ID: 28467 - Posted: 09.10.2022

Researchers have published two papers describing how they identified a potential new pathway for treating a sporadic form of amyotrophic lateral sclerosis (ALS). The studies were published as part of a cooperative research agreement between the National Institute of Neurological Disorders and Stroke (NINDS), part of the National Institutes of Health, and the Switzerland-based biotechnology company GeNeuro Inc. One unusual side effect of hundreds of thousands of years of evolution is that the human genome now contains DNA sequences from ancient retroviruses—referred to as human endogenous retroviruses (HERVs). Though most remain dormant, reactivation of HERVs have been implicated in several neurodegenerative diseases, including ALS. The first of these papers shows that a specific HERV produces a protein that can be found in the cerebrospinal fluid (CSF) of people with ALS. This protein, called HERV-K ENV, is toxic when added to neurons grown in laboratory dishes. In addition, a special kind of mouse genetically designed to create HERV-K ENV develops symptoms very similar to ALS. Adding the CSF from people with ALS to lab-grown neurons resulted in damage to the cells. When a synthetic antibody designed specifically to recognize HERV-K ENV was added as well to those neurons, the toxic effects were reduced. These findings together suggest that the improper activation of the HERV-K ENV gene could be the cause of the symptoms seen in certain cases of sporadic ALS. The discovery that a synthetic antibody to HERV-K ENV could be protective led the researchers to look at whether the immune system of people with ALS produced any antibodies, as well. In the second paper, the authors show that indeed higher levels of antibodies against HERV-K ENV were seen in the blood of a group of people with ALS as compared to healthy donors. The pattern of antibodies against this viral protein was also more complex in persons with ALS. In addition, there was also a correlation between higher antibody levels against HERV-K ENV and longer overall survival.

Keyword: ALS-Lou Gehrig's Disease
Link ID: 28455 - Posted: 08.31.2022

By Pam Belluck An experimental therapy for A.L.S., the paralyzing and fatal neurological disorder, has been approved in Canada, adding a new treatment option for a disease for which there are few effective therapies. The approval, the first in the world for the treatment — AMX0035, to be marketed in Canada as Albrioza — comes with the condition that the drug company later provide better evidence that the treatment works. It is likely to be of major interest to patients with A.L.S. (amyotrophic lateral sclerosis) in the United States, where the same therapy is being evaluated by the Food and Drug Administration, which has raised questions about the treatment’s effectiveness. An F.D.A. review earlier this year found the treatment to be safe, but said there was not enough evidence that it was effective either in helping patients live longer or slowing the rate at which they lose functions like muscle control, speaking or breathing without assistance. A committee of independent advisers to the F.D.A. voted by a narrow margin in March that the therapy was not ready for approval. The F.D.A. had been scheduled to issue a final decision this month, but recently extended the deadline to Sept. 29, saying it needed more time to review additional analyses of data submitted by the company. In the meantime, Calaneet Balas, president and chief executive of the A.L.S. Association, one of several patient advocacy organizations pressing for F.D.A. approval, said, “We expect that Americans living with A.L.S. will try to access Albrioza in Canada, just as we have heard reports of people trying to buy the ingredients on Amazon.” © 2022 The New York Times Company

Keyword: ALS-Lou Gehrig's Disease
Link ID: 28369 - Posted: 06.14.2022

By Maria Temming The Terminator may be one step closer to reality. Researchers at the University of Tokyo have built a robotic finger that, much like Arnold Schwarzenegger’s titular cyborg assassin, is covered in living human skin. The goal is to someday build robots that look like real people — albeit for more altruistic applications. Super realistic-looking robots could more seamlessly interact with humans in medical care and service industries, say biohybrid engineer Shoji Takeuchi and his colleagues June 9 in Matter. (Whether cyborgs masked in living tissue would be more congenial or creepy is probably in the eye of the beholder.) To cover the finger in skin, Takeuchi and colleagues submerged the robotic digit in a blend of collagen and human skin cells called dermal fibroblasts. The mixture settled into a base layer of skin, or dermis, covering the finger. The team then poured a liquid containing human keratinocyte cells onto the finger, which formed an outer skin layer, or epidermis. After two weeks, skin covering the finger measured a few millimeters thick — comparable to the thickness of human skin. The lab-made skin was strong and stretchy enough to withstand the robotic finger bending. It could also heal itself: When researchers made a small cut on the robotic finger and covered it with a collagen bandage, the skin’s fibroblast cells merged the bandage with the rest of the skin within a week. Researchers at the University of Tokyo covered this robotic finger in living human skin to pave the way for ultrarealistic cyborgs. “This is very interesting work and an important step forward in the field,” says Ritu Raman, an MIT engineer who also builds machines with living components. “Biological materials are appealing because they can dynamically sense and adapt to their environments.” For instance, she’d like to see a future version of the living robot skin embedded with nerve cells to make robots more aware of their surroundings. © Society for Science & the Public 2000–2022.

Keyword: Pain & Touch; Robotics
Link ID: 28365 - Posted: 06.11.2022

ByRobert F. Service An experimental drug is raising new hopes for those with Parkinson’s disease. So far, the compound has only been tested in animals and in an initial safety assessment in humans. But results show it inhibits a cellular pathway that gives rise to the disease, which researchers have been working to target for nearly 20 years. Investigators are now launching expanded clinical trials. “This is a very, very important step forward,” says Patrick Lewis, a neuroscientist who studies the mechanisms of Parkinson’s at the University of London’s Royal Veterinary College. If further tests prove the compound is effective in humans, says Lewis, who was not involved with the new study, it would likely be given to patients as soon as they exhibit the first signs of developing the progressive disorder. “The hope is that [the new drug] would slow down the progression of disease.” Parkinson’s affects as many as 10 million people worldwide. It results when cells in the brain that produce the neurotransmitter dopamine stop working or die. Over time this causes a widespread decline in brain function, leading to shaking and loss of muscle control. Current drugs can help replace lost dopamine and reduce symptoms, but no therapies slow or halt disease progression itself. The new study focuses on a gene called leucine-rich repeat kinase 2 (LRRK2). People with mutations in this gene are at high risk for developing Parkinson’s. Among other roles, LRRK2 modifies a suite of proteins called Rab guanosine triphosphates, which act like air traffic controllers, orchestrating the flow of proteins in and out of cells. The mutations kick Rab into overdrive and reduce the efficiency of cellular structures called lysosomes, which chew up and recycle unwanted proteins. This creates a buildup of toxic byproducts that can kill neurons and lead to Parkinson’s, says Carole Ho, chief medical officer of Denali Therapeutics, a biotech startup in California. © 2022 American Association for the Advancement of Science.

Keyword: Parkinsons
Link ID: 28362 - Posted: 06.09.2022

By Lisa Sanders, M.D. “You have to take your husband to the hospital right now,” the doctor urged over the phone. “His kidneys aren’t working at all, and we need to find out why.” The woman looked at her 82-year-old spouse. He was so thin and pale. She thanked the doctor and called 911. For the past couple of months, every meal was a struggle. Swallowing food was strangely difficult. Liquids were even worse. Whatever he drank seemed to go down the wrong pipe, and he coughed and sputtered after almost every sip. It was terrifying. He saw an ear, nose and throat specialist, who scoped his mouth and esophagus. There wasn’t anything blocking the way. The doctor recommended that he get some therapy to help him strengthen the muscles he used to swallow, and until he did that, he should thicken his liquids to make drinking easier. The patient tried that once, but it was so disgusting he gave up on it. His wife was worried as she watched him eat and drink less and less. She could see that he was getting weaker every day. He had a stroke four months earlier, and since then his right foot dragged a little. But now she had to help him get out of his recliner. And he wasn’t able to drive — she had to make the 45-minute trip with him each day to his office. Finally, he agreed to see Dr. Richard Kaufman, their primary-care doctor. Kaufman was shocked by the man’s appearance, how the skin on his face hung in folds as if air had been let out of his cheeks. He’d lost nearly 40 pounds. He struggled to walk the few steps to the exam table. His right side, which was weakened by his stroke, was now matched by weakness on his left side. His stroke hadn’t done this. There was something else going on. Kaufman ordered some preliminary blood tests to try to see where the problem might lie. Those were the results that sent the couple to the emergency room. © 2022 The New York Times Company

Keyword: Neuroimmunology; Muscles
Link ID: 28339 - Posted: 05.28.2022

By Veronique Greenwood Lovebirds, small parrots with vibrant rainbow plumage and cheeky personalities, are popular pets. They swing from ropes, cuddle with companions and race for treats in a waddling gait with all the urgency of toddlers who spot a cookie. But, along with other parrots, they also do something strange: They use their faces to climb walls. Give these birds a vertical surface to clamber up, and they cycle between left foot, right foot and beak as if their mouths were another limb. In fact, a new analysis of the forces climbing lovebirds exert reveals that this is precisely what they are doing. Somehow, a team of scientists wrote in the journal Proceedings of the Royal Society B on Wednesday, the birds and perhaps other parrot species have repurposed the muscles in their necks and heads so they can walk on their beaks, using them the way rock climbers use their arms. Climbing with a beak as a third limb is peculiar because third limbs generally are not something life on Earth is capable of producing, said Michael Granatosky, an assistant professor of anatomy at the New York Institute of Technology and an author of the new paper. “There is this very deep, deep set aspect of our biology that everything is bilateral” in much of the animal kingdom, he said. The situation makes it developmentally unlikely to grow an odd numbers of limbs for walking. Some animals have developed workarounds. Kangaroos use their tails as a fifth limb when hopping slowly, pushing off from the ground with their posteriors the same way they push with their feet. To see if parrots were using their beaks in a similar way, Dr. Granatosky and a graduate student, Melody Young, as well as their colleagues brought six rosy-faced lovebirds from a pet store into the lab. They had the birds climb up a surface that was fitted with a sensor to keep track of how much force they were exerting and in what directions. The scientists found that the propulsive force the birds applied through their beaks was similar to what they provided with their legs. What had started as a way to eat had transformed into a way to walk, with beaks as powerful as their limbs. © 2022 The New York Times Company

Keyword: Evolution
Link ID: 28336 - Posted: 05.25.2022

Nicola Davis Science correspondent Mice with spinal cord injuries have shown remarkable recovery after being given a drug initially developed for people with lung disease, researchers have revealed, saying the treatment could soon be tested on humans. It is thought there are about 2,500 new spinal cord injuries in the UK every year, with some of those affected experiencing full loss of movement as a result. Despite a number of promising areas of research, at present damage to the spinal cord is not reversible. Now researchers at the University of Birmingham say a drug called AZD1236, initially developed to treat chronic obstructive pulmonary disease in humans, has shown promise in mice with spinal cord compression injuries, a type of injury often associated with motor accidents in humans, but which is also linked to conditions such as osteoarthritis. A similar drug, called AZD3342, showed comparable benefits in rats. The results, published in the journal Clinical and Translational Medicine, suggested the drugs block the action of enzymes known as MMP-9 and MMP-12 that rise after spinal cord injury. The upshot was that swelling of the spinal cord was reduced, levels of proteins linked to inflammation and pain were lowered, and breakdown of the blood-spinal cord barrier was limited. Scarring of connective tissue was also reduced. The team said that compared with injured mice not given AZD1236, those given the drug for three days showed 85% improvement in movement and sensation six weeks after the spinal injury, while their nerve function was 80% of that seen in uninjured mice. Furthermore, the benefits were similar whether the drug was given immediately after spinal injury or 24 hours later. © 2022 Guardian News & Media Limited

Keyword: Regeneration
Link ID: 28333 - Posted: 05.21.2022

By Ferris Jabr To hear more audio stories from publications like The New York Times, download Audm for iPhone or Android. On the evening of Oct. 10, 2006, Dennis DeGray’s mind was nearly severed from his body. After a day of fishing, he returned to his home in Pacific Grove, Calif., and realized he had not yet taken out the trash or recycling. It was raining fairly hard, so he decided to sprint from his doorstep to the garbage cans outside with a bag in each hand. As he was running, he slipped on a patch of black mold beneath some oak trees, landed hard on his chin, and snapped his neck between his second and third vertebrae. While recovering, DeGray, who was 53 at the time, learned from his doctors that he was permanently paralyzed from the collarbones down. With the exception of vestigial twitches, he cannot move his torso or limbs. “I’m about as hurt as you can get and not be on a ventilator,” he told me. For several years after his accident, he “simply laid there, watching the History Channel” as he struggled to accept the reality of his injury. Some time later, while at a fund-raising event for stem-cell research, he met Jaimie Henderson, a professor of neurosurgery at Stanford University. The pair got to talking about robots, a subject that had long interested DeGray, who grew up around his family’s machine shop. As DeGray remembers it, Henderson captivated him with a single question: Do you want to fly a drone? Henderson explained that he and his colleagues had been developing a brain-computer interface: an experimental connection between someone’s brain and an external device, like a computer, robotic limb or drone, which the person could control simply by thinking. DeGray was eager to participate, eventually moving to Menlo Park to be closer to Stanford as he waited for an opening in the study and the necessary permissions. In the summer of 2016, Henderson opened DeGray’s skull and exposed his cortex — the thin, wrinkled, outermost layer of the brain — into which he implanted two 4-millimeter-by-4-millimeter electrode arrays resembling miniature beds of nails. Each array had 100 tiny metal spikes that, collectively, recorded electric impulses surging along a couple of hundred neurons or so in the motor cortex, a brain region involved in voluntary movement. © 2022 The New York Times Company

Keyword: Robotics
Link ID: 28326 - Posted: 05.14.2022

By Laura Sanders Deep in the human brain, a very specific kind of cell dies during Parkinson’s disease. For the first time, researchers have sorted large numbers of human brain cells in the substantia nigra into 10 distinct types. Just one is especially vulnerable in Parkinson’s disease, the team reports May 5 in Nature Neuroscience. The result could lead to a clearer view of how Parkinson’s takes hold, and perhaps even ways to stop it. The new research “goes right to the core of the matter,” says neuroscientist Raj Awatramani of Northwestern University Feinberg School of Medicine in Chicago. Pinpointing the brain cells that seem to be especially susceptible to the devastating disease is “the strength of this paper,” says Awatramani, who was not involved in the study. Parkinson’s disease steals people’s ability to move smoothly, leaving balance problems, tremors and rigidity. In the United States, nearly 1 million people are estimated to have Parkinson’s. Scientists have known for decades that these symptoms come with the death of nerve cells in the substantia nigra. Neurons there churn out dopamine, a chemical signal involved in movement, among other jobs (SN: 9/7/17). But those dopamine-making neurons are not all equally vulnerable in Parkinson’s, it turns out. “This seemed like an opportunity to … really clarify which kinds of cells are actually dying in Parkinson’s disease,” says Evan Macosko, a psychiatrist and neuroscientist at Massachusetts General Hospital in Boston and the Broad Institute of MIT and Harvard. © Society for Science & the Public 2000–2022.

Keyword: Parkinsons
Link ID: 28320 - Posted: 05.07.2022

Liam Drew James Johnson hopes to drive a car again one day. If he does, he will do it using only his thoughts. In March 2017, Johnson broke his neck in a go-carting accident, leaving him almost completely paralysed below the shoulders. He understood his new reality better than most. For decades, he had been a carer for people with paralysis. “There was a deep depression,” he says. “I thought that when this happened to me there was nothing — nothing that I could do or give.” But then Johnson’s rehabilitation team introduced him to researchers from the nearby California Institute of Technology (Caltech) in Pasadena, who invited him to join a clinical trial of a brain–computer interface (BCI). This would first entail neurosurgery to implant two grids of electrodes into his cortex. These electrodes would record neurons in his brain as they fire, and the researchers would use algorithms to decode his thoughts and intentions. The system would then use Johnson’s brain activity to operate computer applications or to move a prosthetic device. All told, it would take years and require hundreds of intensive training sessions. “I really didn’t hesitate,” says Johnson. The first time he used his BCI, implanted in November 2018, Johnson moved a cursor around a computer screen. “It felt like The Matrix,” he says. “We hooked up to the computer, and lo and behold I was able to move the cursor just by thinking.” Johnson has since used the BCI to control a robotic arm, use Photoshop software, play ‘shoot-’em-up’ video games, and now to drive a simulated car through a virtual environment, changing speed, steering and reacting to hazards. “I am always stunned at what we are able to do,” he says, “and it’s frigging awesome.” © 2022 Springer Nature Limited

Keyword: Brain imaging; Robotics
Link ID: 28292 - Posted: 04.20.2022

Allison Whitten Every time you reach for your coffee mug, a neuroscientific mystery takes shape. Moments before you voluntarily extend your arm, thousands of neurons in the motor regions of your brain erupt in a pattern of electrical activity that travels to the spinal cord and then to the muscles that power the reach. But just prior to this massively synchronized activity, the motor regions in your brain are relatively quiet. For self-driven movements like reaching for your coffee, the “go” signal that tells the neurons precisely when to act — instead of the moment just before or after — has yet to be found. In a recent paper in eLife, a group of neuroscientists led by John Assad at Harvard Medical School finally reveals a key piece of the signal. It comes in the form of the brain chemical known as dopamine, whose slow ramping up in a region lodged deep below the cortex closely predicted the moment that mice would begin a movement — seconds into the future. Dopamine is commonly known as one of the brain’s neurotransmitters, the fast-acting chemical messengers that are shuttled between neurons. But in the new work, dopamine is acting as a neuromodulator. It’s a term for chemical messengers that slightly alter neurons to cause longer-lasting effects, including making a neuron more or less likely to electrically communicate with other neurons. This neuromodulatory tuning mechanism is perfect for helping to coordinate the activity of large populations of neurons, as dopamine is likely doing to help the motor system decide precisely when to make a movement. The new paper is one of the latest results to expand our knowledge of the crucial and varied roles that neuromodulators play in the brain. With recent advances in technology, neuroscientists can now view neuromodulators at work in networks that traverse the entire brain. The new findings are overturning some long-held views about these modulators adrift in the brain, and they’re revealing exactly how these molecules allow the brain to flexibly change its internal state amid ever-changing environments. All Rights Reserved © 2022

Keyword: Movement Disorders; Drug Abuse
Link ID: 28251 - Posted: 03.23.2022

Linda Geddes A completely locked-in patient is able to type out words and short sentences to his family, including what he would like to eat, after being implanted with a device that enables him to control a keyboard with his mind. The findings, published in Nature Communications, overturn previous assumptions about the communicative abilities of people who have lost all voluntary muscle control, including movement of the eyes or mouth, as well as giving a unique insight into what it’s like to be in a “locked in” state. Locked-in syndrome – also known as pseudocoma - is a rare condition, where people are conscious and can see, hear, and smell, but are unable to move or speak due to complete paralysis of their voluntary muscles, eg as a result of the progressive neurodegenerative disease amyotrophic lateral sclerosis (ALS). Advertisement Some can communicate by blinking or moving their eyes, but those with completely locked-in syndrome (CLIS) cannot even control their eye muscles. In 2017, doctors at the University of Tübingen in Germany enabled three patients with CLIS to answer “yes” or “no” to questions by detecting telltale patterns in their brain activity, using a technology called functional near-infrared spectroscopy (fNIRS). The advance generated widespread media coverage, and prompted the parents of the current patient, who was diagnosed with ALS in 2015, to write to the medical team, saying he was losing the ability to communicate with his eye movements, and could they help. The problem with using fNIRS to help CLIS patients to communicate is that it is relatively slow, and only gives the correct answer 70% of the time, meaning questions have to be repeated to get a reliable answer. “It was always our goal to enable a patient in a completely locked down state to spell out words, but with a classification accuracy of 70%, it is almost impossible to enable free spelling,” said Dr Ujwal Chaudhary, a biomedical engineer and managing director of ALS Voice gGmbH in Mössingen, Germany, who co-led the research. © 2022 Guardian News & Media Limited

Keyword: ALS-Lou Gehrig's Disease ; Movement Disorders
Link ID: 28250 - Posted: 03.23.2022

By Linda Searing The more fit you are, the less likely you may be to develop Alzheimer’s disease — with those who are the most fit having a 33 percent lower risk for this dementia than the least fit, according to a report to be presented to the American Academy of Neurology at its annual meeting next month. FAQ: What to know about the omicron variant of the coronavirus D.C.-based researchers, from the Washington VA Medical Center and George Washington University, tested and tracked 649,605 veterans (average age 61) for nearly a decade. Based on their cardiorespiratory fitness, participants were divided into five categories, from lowest to highest fitness level. 10-minute exercising may slow progression to dementia for those with mild cognitive impairment The researchers found that, as fitness improved, people’s chances of developing the ailment decreased. Compared with the least-fit group, those slightly more fit had a 13 percent lower risk for Alzheimer’s; the middle group was 20 percent less likely to develop the disease; the next higher group was 26 percent less likely; with the odds reaching a 33 percent lower risk for those in the most-fit group. Alzheimer’s is the most common type of dementia. It is a progressive brain disorder that, over time, destroys memory and thinking skills and interferes with the ability to carry out daily tasks. About 6 million Americans 65 and older have Alzheimer’s. There are no proven ways to cure the disease. © 1996-2022 The Washington Post

Keyword: Alzheimers
Link ID: 28239 - Posted: 03.16.2022

By Gina Kolata Dr. John Q. Trojanowski, a neuropathologist whose work was at the forefront of research on Alzheimer’s and other neurodegenerative diseases, died on Feb. 8 in a hospital in Philadelphia. He was 75. His wife and longtime collaborator, Virginia M.-Y. Lee, said the cause was complications of chronic spinal cord injuries. Dr. Trojanowski “was a giant in the field,” said Leslie Shaw, a professor with Dr. Trojanowski in the department of pathology and laboratory medicine at the University of Pennsylvania — adding that he meant that in two ways. At 6 feet 4 inches, Dr. Trojanowski towered over his colleagues. And, Dr. Shaw said, he was also a towering figure in his field, whose scientific contributions were “phenomenal” because they combined pathology and biochemistry to figure out what goes wrong, and why, when people get diseases as disparate as Alzheimer’s, Parkinson’s and A.L.S. The results can lead to improved diagnosis and potential treatments. Key to the work Dr. Trojanowski did with Dr. Lee was their establishment of a brain bank: stored brains from patients with diseases like Alzheimer’s and Parkinson’s, as well as from people without degenerative brain diseases. It allowed them to compare the brains of people with and without the conditions and ask what proteins were involved in the diseases and what brain regions were affected. Among their first quests was an attempt to solve the mystery of strange areas in the brains of people with Alzheimer’s. Known as tangles and first described by Alois Alzheimer himself at the turn of the 20th century, they look like twisted strands of spaghetti in dying nerve cells. In 1991, Dr. Trojanowski and Dr. Lee determined that the regions are made up of a malformed protein called tau, which causes the structure of nerve cells to collapse. At a time when most Alzheimer’s researchers and drug companies were focused on a different protein, amyloid, Dr. Trojanowski and Dr. Lee insisted that tau was equally important. They then discovered that it also played a central role in a rare group of degenerative dementias known as frontotemporal lobar degeneration. © 2022 The New York Times Company

Keyword: Alzheimers; ALS-Lou Gehrig's Disease
Link ID: 28225 - Posted: 03.02.2022

By Amanda Coletta Health officials in New Brunswick released a long-awaited report Thursday into a mysterious and debilitating neurological disorder that has struck dozens of people with bizarre symptoms — including a belief that family members have been replaced by impostors — stumped doctors and stoked fears across the province. The conclusion? There is no new disorder. “The oversight committee has unanimously agreed that these 48 people should never have been identified as having a neurological syndrome of unknown cause, and that based on the evidence reviewed, no such syndrome exists,” said Jennifer Russell, chief medical officer of health for the Canadian province. “Public Health concurs with these findings. But I stress again, this does not mean that these people aren’t seriously ill. It means they are ill with a known neurological condition.” The report’s authors say the 48 cases in what was thought to be a cluster were randomly allocated to pairs of neurologists who reviewed them and presented their findings to an oversight committee of six New Brunswick neurologists and other officials. The committee said none of the cases met the full criteria of the case definition. But that finding, coming at the end of an investigation marred by accusations of opacity from the start and allegations that Canada’s top scientists and experts from around the world had been abruptly shut out of the process, appeared unlikely to assuage alarm in the province and more likely to deepen mistrust. Patients and their family members questioned the committee’s findings Thursday, saying the province has not carried out the relevant testing and opted to “abandon scientific rigor in exchange for political expediency.” © 1996-2022 The Washington Post

Keyword: Stress; Prions
Link ID: 28222 - Posted: 02.26.2022

by Laura Dattaro Some genomic areas that help determine cerebellar size are associated with autism, schizophrenia and bipolar disorder, according to a new study. But heritable genetic variants across the genome that also influence cerebellar size are not. The cerebellum sits at the base of the skull, below and behind the much larger cerebrum. It coordinates movement and may also play roles in social cognition and autism, according to previous research. The new work analyzed genetic information and structural brain scans from more than 33,000 people in the UK Biobank, a biomedical and genetic database of adults aged 40 to 69 living in the United Kingdom. A total of 33 genetic sequence variants, known as single nucleotide polymorphisms (SNPs), were associated with differences in cerebellar volume. Only one SNP overlapped with those linked to autism, but the association should be explored further in other cohorts, says lead investigator Richard Anney, senior lecturer in bioinformatics at Cardiff University in Wales. “There’s lots of caveats to say why it might be worth following up on,” Anney says. “But from this data alone, it’s not telling us there’s a major link between [autism] and cerebellar volume.” So far, cognitive neuroscientists have largely ignored the cerebellum, says Jesse Gomez, assistant professor of neuroscience at Princeton University, who was not involved in the work. The new study represents a first step in better understanding genetic influences on the brain region and its role in neurodevelopmental conditions, he says. “It’s a fun paper,” Gomez says. “It’s the beginning of what’s an exciting revolution in the field.” Of the 33 inherited variants Anney’s team found, 5 had not previously been significantly associated with cerebellar volume. They estimated that the 33 variants account for about 50 percent of the differences in cerebellar volume seen across participants. © 2022 Simons Foundation

Keyword: Autism; Genes & Behavior
Link ID: 28215 - Posted: 02.23.2022

Linda Geddes A simple test could end years of uncertainty for people with relatively common neurological conditions, new research has found. Historically, obtaining a definitive diagnosis for conditions including Huntingdon’s disease and some forms of amyotrophic lateral sclerosis has been difficult, because, although the cause of the symptoms is genetic, knowing which test to carry out has resulted in delays of many years. Now, a new study suggests that whole genome sequencing (WGS) can quickly and accurately detect the most common inherited neurological disorders, and could be implemented in routine clinical practice with immediate effect. “It is very exciting because it opens up the vista of a test that could end the diagnostic odyssey for many patients,” said Prof Sir Mark Caulfield from Queen Mary University of London and former chief scientist at Genomics England. “This work paves the way for this to be implemented immediately within the NHS.” WGS is already offered to people in England with rare disorders or childhood cancers through the NHS Genomic Medicine Service. However, the technique wasn’t thought to work on people with ‘repeat expansion disorders’ caused by the insertion of short repetitive chunks of DNA into the genetic code – in some cases, stretching across long distances – because they can be difficult to quantify. Such disorders are relatively common, affecting around one in 3,000 people, and include neurodegenerative and movement disorders such as Fragile X syndrome, Huntington’s disease, Friedreich’s ataxia, and some forms of amyotrophic lateral sclerosis or frontal lobe dementia. © 2022 Guardian News & Media Limited

Keyword: Huntingtons; Genes & Behavior
Link ID: 28210 - Posted: 02.19.2022

By Lisa Sanders, M.D. “OK, I give up,” said the 74-year-old man. “I’ll go to the hospital.” His wife of 46 years gave an inner sigh of relief. Her husband was stubborn, a seventh-​generation Mainer, not given to complaining. But a few weeks earlier, she noticed that he was parking his tractor next to the back porch so he could get on it without pulling himself up. Then he needed help getting out of his big chair. Now he could barely walk. It happened so suddenly it scared her. She eased the car right next to the porch. He needed both hands on the railing to get down, grunting with each step. His legs moved awkwardly, as if they had somehow forgotten what to do. At the LincolnHealth-Miles Campus Hospital in nearby Damariscotta, it was clear to the E.R. doctors that the patient wasn’t weak but ataxic, lacking not strength but coordination. Virtually every movement the body makes requires several muscles working together — a collaboration that occurs in the cerebellum. The uncertain and awkward way the patient moved made doctors at LincolnHealth worry that something — maybe a stroke, maybe a tumor — had injured that part of the brain. But two CT scans and an M.R.I. were unrevealing. When his doctors weren’t sure what to do next, the patient decided it was time to go home. His wife was supportive but worried. How could she help him get around? He was a big guy and outweighed her by 50 pounds. And they still needed to figure out what was wrong with him. Couldn’t they try another hospital? Maybe, he said, but first he wanted to go home. So that’s where she took him. Once there, it took only a day for the man to recognize, again, that he couldn’t just tough it out at home. There was another hospital, a larger one a couple of towns over in Brunswick: Mid Coast Hospital. His wife was happy to take him there. Those few steps he took from porch to car, supported by his wife, were the last he would take for weeks. © 2022 The New York Times Company

Keyword: Movement Disorders; Neuroimmunology
Link ID: 28204 - Posted: 02.16.2022