Latest news with #MartaPaterlini
Yahoo
10-07-2025
- Health
- Yahoo
Scientists Just Ended a 60-Year Debate About the Human Brain
For decades, scientists have argued over one of neuroscience's most fundamental questions: Can the adult human brain grow new neurons? Now, researchers say they finally have the answer, and it changes everything. A team led by Marta Paterlini at the Karolinska Institute in Sweden published their findings in Science. The study confirms that neurogenesis, the process of forming new brain cells, does in fact occur in adult humans—even into old age. Researchers from the Karolinska Institute in Sweden found clear evidence of neural precursor cells and immature neurons in brains ranging from children to adults as old as 78. That discovery finally settles a controversy that's lingered for more than 60 years. In other animals, scientists have long known that the brain continues to make new neurons throughout life. But in humans, evidence was murky. Some previous studies identified young-looking brain cells in adults, but it wasn't clear if they were truly new or just slowly maturing cells leftover from early development. To find out, researchers used advanced RNA sequencing to detect the molecular signatures of newly formed neurons and their precursors. First, they tested brain samples from children. Then, they searched for those same genetic markers in 19 postmortem brains ranging from 13 to 78 years old. They found what they were looking for—proof of active neurogenesis in most of the adult samples, including in regions of the hippocampus, the part of the brain involved in memory and learning. The findings open new doors for brain research, especially when it comes to neurodegenerative diseases and mental health conditions. Disrupted neurogenesis has been linked to Alzheimer's disease and depression in mice, raising the possibility that therapies targeting this process could help prevent or treat these conditions in humans. Knowing these cells still exist in adulthood opens potential pathways for therapies that could stimulate brain now believe other areas of the brain could also support neurogenesis, but that research is still ongoing. This study doesn't just lay to rest a stubborn scientific question. It lays a foundation for new research into brain plasticity, aging, and mental illness. As scientists now have proof of active neurogenesis in adult humans, the next steps will target how to harness and enhance this natural capacity. For now, the long-standing debate has finally been resolved. Adult brains don't just age—they adapt, and in some cases, they even Just Ended a 60-Year Debate About the Human Brain first appeared on Men's Journal on Jul 10, 2025
Yahoo
04-07-2025
- Health
- Yahoo
Can adults make new brain cells? New study may finally settle one of neuroscience's greatest debates
When you buy through links on our articles, Future and its syndication partners may earn a commission. Researchers say they have found clear evidence that the human brain can keep making new neurons well into adulthood, potentially settling decades of controversy. This new neuron growth, or "neurogenesis," takes place in the hippocampus, a critical part of the brain involved in learning, memory and emotions. "In short, our work puts to rest the long-standing debate about whether adult human brains can grow new neurons," co-lead study author Marta Paterlini, a researcher at the Karolinska Institute in Stockholm, told Live Science in an email. Other experts agree that the work makes a strong case for adult neurogenesis. While a single study does not constitute absolute proof, "this is strong evidence in support of the idea" that stem cells and precursors to new neurons exist and are proliferating in the adult human brain, said Dr. Rajiv Ratan, CEO of the Burke Neurological Institute at Weill Cornell Medicine, who was not involved in the study. "This is a perfect example of great science teeing up the ball for the clinical neuroscience community," he told Live Science. Related: Babies' brain activity changes dramatically before and after birth, groundbreaking study finds The researchers combined advanced techniques, including single-nucleus RNA sequencing and machine learning, to sort and examine brain tissue samples from international biobanks, they reported in a paper published July 3 in the journal Science. RNA, a cousin of DNA, reflects genes that are "switched on" inside cells, while machine learning is a type of artificial intelligence often used to crunch huge datasets. Since the 1960s, researchers have known that mice, rats and some nonhuman primates make new brain cells in the dentate gyrus, part of the hippocampus, throughout life. But getting quality brain tissue samples from adult humans is extremely challenging. "Human tissue comes from autopsies or surgeries, so how it's handled — how long before it's fixed in preservative, which chemicals are used, how thin the slices are — can hide those newborn cells," Paterlini said. Employing new technologies enabled the team to overcome this challenge. They analyzed more than 400,000 individual nuclei of hippocampus cells from 24 people, and in addition, looked at 10 other brains using other techniques. The brains came from people ages 0 to 78, including six children and four teens. Using two cutting-edge imaging methods, the team mapped where new cells sat in the tissue. They saw groups of dividing precursor cells sitting right next to the fully formed neurons, in the same spots where animal studies have shown that adult stem cells reside. "We didn't just see these dividing precursor cells in babies and young kids — we also found them in teenagers and adults," Paterlini said. "These include stem cells that can renew themselves and give rise to other brain cells." The newer technologies enabled the researchers to detect the new brain cells at various stages of development and conduct research that wouldn't have been possible a few years ago, Ratan added. The team also used fluorescent tags to mark the proliferating cells. This enabled them to build a machine learning algorithm that identified the cells that they knew would turn into neurogenic stem cells, based on past rodent studies. This was a "clever approach" for tackling the challenges of studying brain-cell formation in adolescents and adults, Ratan said. As expected, the brains of children produced more new brain cells than the brains of adolescents or adults did. Meanwhile, nine out of 14 adult brains analyzed with one technique showed signs of neurogenesis, while 10 out of 10 adult brains analyzed with a second technique bore new cells. Regarding the few brains with no new cells, Paterlini said it's too soon to draw conclusions about the disparity between adult brains with evidence of new cells and those without. RELATED STORIES —How much of your brain do you need to survive? —You're born with most of your neurons — but the brain makes some mysterious new ones in adulthood —Brain aging accelerates dramatically around age 44 — could ketone supplements help? Next, the researchers could explore whether the adults who produced new brain cells did so in response to a neurological disease, such as Alzheimer's, or whether adult neurogenesis is a sign of good brain health, said Dr. W. Taylor Kimberly, chief of neurocritical care at Massachusetts General Brigham, who was not involved in the study. "They were able to find these needles in a haystack," Kimberly told Live Science. "Once you detect them and learn about them and understand their regulation," scientists can research how to track the precursor cells through time and see how their presence relates to disease, he said. He envisioned comparing patients who have dementia to "super agers" who are cognitively resilient in old age. If the link between neurogenesis and disease can be uncovered, perhaps that could open the door to treatments. "Although the precise therapeutic strategies in humans are still under active research," Paterlini said, "the very fact that our adult brains can sprout new neurons transforms how we think about lifelong learning, recovery from injury and the untapped potential of neural plasticity."
Gizmodo
03-07-2025
- Health
- Gizmodo
New Research Debunks Myth That Brain Cells Stop Growing After Childhood
You've probably heard the old canard that new brain cells simply stop forming as we become adults. But research out today is the latest to show that this isn't really true. Scientists in Sweden led the study, published Thursday in Science. They found abundant signs of neural stem cells growing in the hippocampus of adult brains. The findings reveal more about the human brain as we get older, the researchers say, and also hint at potential new ways to treat neurological disorders. 'We've found clear evidence that the human brain keeps making new nerve cells well into adulthood,' study co-author Marta Paterlini, a neuroscientist at the Karolinska Institute in Stockholm, told Gizmodo. This Is What Your Brain Looks Like When You Solve a Problem This isn't the first paper to chip away at the idea of new neurons ceasing to form in adulthood (a concept not to be confused with general brain development, which does seem to reach maturity around age 30). In 2013, study researcher Jonas Frisén and his team at the Karolinska Institute concluded that substantial neuron growth—also known as neurogenesis—occurs throughout our lives, albeit with a slight decline as we become elderly. But there's still some debate ongoing among scientists. In spring 2018, for instance, two different studies of neurogenesis published a month apart came to the exact opposite conclusion. The researchers were hoping to settle one particular aspect of human neurogenesis in adults. If we do keep growing new neurons as we age, then we should be able to spot the cells that eventually mature into neurons, neural progenitor cells, growing and dividing inside the adult brain. To look for these cells, the team analyzed brain tissue samples from people between the ages of 0 and 78 using relatively new advanced methods. These methods allowed them to figure out the characteristics of brain cells on an individual level and to track the genes being expressed by a single cell's nucleus. All told, the researchers examined more than 400,000 individual cell nuclei from these samples. And as hoped, they found these progenitor cells along various stages of development in adult brains, including cells just about to divide. They also pinpointed the location within the hippocampus where the new cells appeared to originate: the dentate gyrus, a brain region critical to helping us form certain types of memory. 'We saw groups of dividing precursors sitting right next to the fully formed nerve cells, in the same spots where animal studies have shown adult stem cells live,' said Paterlini, a senior scientist at the Frisén lab. 'In short, our work puts to rest the long-standing debate about whether adult human brains can grow new neurons.' Something Strange Happens to Brains During a Marathon The findings, as is often true in science, foster more questions in need of an answer. Our adult precursor cells seem to have different patterns of gene activity compared to the cells found in pigs, mice, and other mammals with clear evidence of adult neurogenesis, for instance. The researchers also found that some adults' brains were filled with these growing precursors, while others had relatively few. These differences—combined with the team's earlier research showing that adult neurogenesis slows down over time—may help explain people's varying risk of neurological or psychological conditions, the authors say. And likewise, finding a safe way to improve the adult brain's existing ability to grow new cells could help treat these conditions or improve people's recovery from serious head injuries. 'Although precise therapeutic strategies for humans are still being researched, the simple fact that our adult brains can generate new neurons radically changes the way we view lifelong learning, recovery from injury, and the untapped potential of neuronal plasticity,' said Paterlini. There's plenty more to be learned about how our brains change over time. The team is planning to investigate other likely hotspots of neurogenesis in the adult brain, such as the wall of the lateral ventricles (c-shaped cavities found in each of the brain's cerebral hemispheres) and nearby regions. But we can be fairly certain that our neurons keep on growing and replacing themselves into adulthood—at least for some of us.
