Chapter 16. None
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By SABRINA TAVERNISE WASHINGTON — What would make a smoker more likely to quit, a big reward for succeeding or a little penalty for failing? That is what researchers wanted to know when they assigned a large group of CVS employees, their relatives and friends to different smoking cessation programs. The answer offered a surprising insight into human behavior. Many more people agreed to sign up for the reward program, but once they were in it, only a small share actually quit smoking. A far smaller number agreed to risk the penalty, but those who did were twice as likely to quit. The trial, which was described in The New England Journal of Medicine on Wednesday, was the largest yet to test whether offering people financial incentives could lead to better health. It used theories about human decision making that have been developed in psychology and economics departments over several decades and put them into practice with more than 2,500 people who either worked at CVS Caremark, the country’s largest drugstore chain by sales, or were friends or relatives of those employees. Researchers found that offering incentives was far more effective in getting people to stop smoking than the traditional approach of giving free smoking cessation help, such as counseling or nicotine replacement therapy like gum, medication or patches. But they also found that requiring a $150 deposit that would be lost if the person failed to stay off cigarettes for six months nearly doubled the chances of success. “Adding a bit of a stick was much better than a pure carrot,” said Dr. Scott Halpern, deputy director of the Center for Health Incentives and Behavioral Economics at the University of Pennsylvania School of Medicine, who led the study. © 2015 The New York Times Company
Keyword: Drug Abuse
Link ID: 20925 - Posted: 05.14.2015
Alison Abbott It is only when you read the words that Andreas Vesalius wrote as an angry young man in the 1540s that you get a feeling for what drove him to document every scrap of human anatomy his eye could see. His anger was directed at Galen, the second-century physician whose anatomical teachings had been held as gospel for more than a millennium. Roman Empire law had barred Galen from dissecting humans, so he had extrapolated as best he could from animal dissections — often wrongly. Human dissections were also banned in most of sixteenth-century Europe, so Vesalius travelled to wherever they were allowed. He saw Galen's errors and dared to report them, most explicitly in his seven-volume De Humani Corporis Fabrica (On the Fabric of the Human Body), which he began aged 24, working with some of the best art professionals of the time. His mission to learn through direct and systematic observation marked the start of a new way of doing science. In Brain Renaissance, neuroscientists Marco Catani and Stefano Sandrone present a translation from the Latin of the Fabrica's last volume, which focuses on the brain. Through it we can appreciate Vesalius's extraordinary attention to detail, and his willingness to believe his eyes, even when what he saw contradicted established knowledge. We learn his anatomical vocabulary. For example, he called the rounded surface protuberances near the brain stem “buttocks” and “testes”; these are now known as the inferior and superior colliculi, or 'little hills', which process sound and vision. © 2015 Macmillan Publishers Limited.
Keyword: Brain imaging
Link ID: 20924 - Posted: 05.14.2015
By Gareth Cook Much has been written on the wonders of human memory: the astounding feats of recall, the way memories shape our identity and are shaped by them, memory as a literary theme and a historical one. But what of forgetting? This is the topic of a new book by Douwe Draaisma, author of The Nostalgia Factory and a professor of the history of psychology at the University of Groningen. In Forgetting, Draaisma considers dreaming, amnesia, dementia and all of the ways that our minds — and lives — are shaped by memory’s opposite. He answered questions from Mind Matters editor Gareth Cook. What is your earliest memory and why, do you suppose, have you not forgotten it? Quite a few early memories in the Netherlands involve bicycles, and mine is no exception. I was two-and-a-half years old when my aunts walked my mother to the train station. They had taken a bike along to transport her bags. I was sitting on the back of the bike. Suddenly the whole procession came to a halt when my foot got caught between the spokes. I’m pretty sure this memory is accurate, since I had to see a doctor and there is a dated medical record. It’s a brief, snapshot-like memory, black-and-white. I don’t remember any pain, but I do remember the consternation among my mom and her sisters. Looking back on this memory from a professional perspective, I would say that it has the flash-like character typical for first memories from before age 3; ‘later’ first memories are usually a bit longer and more elaborate. It also fits the pattern of being about pain and danger. Roughly three in four first memories are associated with negative emotions. This may have an evolutionary origin: I never again had my foot between the spokes. And neither have any of my children. © 2015 Scientific American
Keyword: Learning & Memory
Link ID: 20918 - Posted: 05.13.2015
Jessica Hamzelou Don't be too hard on them. Amoebas that weasel their way into our brains and chow down on our grey matter aren't welcome, but it's how our immune system reacts that's really lethal. Setting the story straight could help us deal with them better. Brain-eating amoebas (Naegleria fowleri) are found in warm freshwater pools around the world, feeding on bacteria. If someone swims in one of these pools and gets water up their nose, the amoeba heads for the brain in search of a meal. Once there, it starts to destroy tissue by ingesting cells and releasing proteins that make other cells disintegrate. The immune system launches a counter-attack by flooding the brain with immune cells, causing inflammation and swelling. It seldom works: of the 132 people known to have been infected in the US since 1962, only three survived. Brain-eating amoeba infections are more common elsewhere. "In Pakistan, we have something like 20 deaths per year," says Abdul Mannan Baig at the Aga Khan University in Karachi. There is no standard treatment. Doctors in the US have recently started trying to kill the amoebas with miltefosine, a drug known to work on the leishmaniasis parasite. Mannan thinks they should take a different approach, because the immune response may be more damaging than the amoeba itself. The problem is that enzymes released by the immune cells can also end up destroying brain tissue. And the swelling triggered by the immune system eventually squashes the brainstem, fatally shutting off communication between the body and the brain. © Copyright Reed Business Information Ltd
Link ID: 20917 - Posted: 05.13.2015
By C. CLAIBORNE RAY Q. I heard that people can’t look at a color in one room and then pick it out of a set of similar colors in the next room. But there are people with perfect pitch, so are there people with “perfect hue”? A. “The short answer is no,” said Mark D. Fairchild, director of the program of color science at the Munsell Color Science Laboratory of Rochester Institute of Technology. “Color is almost always judged relative to other colors,” Dr. Fairchild said, and the human ability to remember colors over any period of time, or even from room to room, is extremely poor. “Based on memory alone, we can probably reliably identify tens of colors, with some people perhaps able to study hard and get up to a hundred or so,” he said. “If we were to learn a systematic way to scale colors, we might be able to get up to several hundred.” If colors are compared side by side, however, “then we can easily distinguish several thousand colors, and some estimate more than a million,” Dr. Fairchild said. Such ability is somewhat analogous to differentiating tones in hearing, he said. Almost everyone can distinguish tones when they are compared in close succession, he said, but only a very small percentage of people have what is called perfect pitch or absolute pitch: the ability to recall and identify tones after a considerable period of time, without a reference tone for comparison. “Unfortunately, color appearance seems to be even more difficult to remember,” Dr. Fairchild said, “to the point that we don’t speak of anyone as having perfect hue.” © 2015 The New York Times Company
Link ID: 20916 - Posted: 05.13.2015
By Simon Makin After wandering around an unfamiliar part of town, can you sense which direction to travel to get back to the subway or your car? If so, you can thank your entorhinal cortex, a brain area recently identified as being responsible for our sense of direction. Variation in the signals in this area might even explain why some people are better navigators than others. The new work adds to a growing understanding of how our brain knows where we are. Groundbreaking discoveries in this field won last year's Nobel Prize in Physiology or Medicine for John O'Keefe, a neuroscientist at University College London, who discovered “place cells” in the hippocampus, a brain region most associated with memory. These cells activate when we move into a specific location, so that groups of them form a map of the environment. O'Keefe shared the prize with his former students Edvard Moser and May-Britt Moser, both now at the Kavli Institute for Systems Neuroscience in Norway, who discovered “grid cells” in the entorhinal cortex, a region adjacent to the hippocampus. Grid cells have been called the brain's GPS system. They are thought to tell us where we are relative to where we started. A third type—head-direction cells, also found in the entorhinal region—fires when we face a certain direction (such as “toward the mountain”). Together these specialized neurons appear to enable navigation, but precisely how is still unclear. For instance, in addition to knowing which direction we are facing, we need to know which direction to travel. Little was known about how or where such a goal-direction signal might be generated in the brain until the new study. © 2015 Scientific American
Keyword: Learning & Memory
Link ID: 20915 - Posted: 05.13.2015
By Smitha Mundasad Health reporter There has been a worrying rise in the number of working-age men and women having strokes, a charity has warned. In England in 2014 there were 6,221 hospital admissions for men aged 40-54 - a rise of 1,961 on 14 years earlier, a Stroke Association study shows. Experts said unhealthy lifestyles were partly to blame for the rise, though the growing population and changes to hospital practice also played a part. Overall the rate of strokes is going down in the UK, however. Researchers say based on their findings strokes should not be considered as a disease of the old. Strokes are caused by blood clots or bleeds to the brain and can lead to long-lasting disability. The majority occur in people aged over 65, and though rates are decreasing in this group, this report suggests growing numbers of younger people are at risk. Experts analysed national hospital admission data spanning 2000 to 2014. Trends for people in their 40s and early 50s appeared to be getting worse. In women aged 40-54, there were an extra 1,075 strokes recorded in 2014, compared with 2000. Experts said growing obesity levels, sedentary lives and unhealthy diets - which raise the risks of dangerous blood clots - all played a part. And they argued strokes among this age group had long-lasting personal and financial impacts on individuals and their families, as well as on the economy. Recovering patients can find it difficult to return to work and should have more support from employers, the report suggests. Jon Barrick, of the Stroke Association, said: "These figures show stroke can no longer be seen as a disease of older people. "There is an alarming increase in the numbers of people having a stroke in working age. © 2015 BBC.
Link ID: 20912 - Posted: 05.12.2015
Tina Hesman Saey COLD SPRING HARBOR, N.Y. — Taming animals makes an impression on their DNA. Domesticated animals tend to have genetic variants that affect similar biological processes, such as brain and facial development and fur coloration. Alex Cagan of the Max Planck Institute for Evolutionary Anthropology in Leipzig, Germany, reported the results May 6 at the Biology of Genomes conference. Cagan and colleagues examined DNA in Norway rats (Rattus norvegicus) that had been bred for 70 generations to be either tame or aggressive toward humans. Docility was associated with genetic changes in 1,880 genes in the rats. American minks (Neovison vison) bred for tameness over 15 generations had tameness-associated variants in 525 genes, including 82 that were also changed in the rats. The researchers also compared other domesticated animals, including dogs, cats, pigs and rabbits, with their wild counterparts. The domestic species and the minks had tameness-associated changes in genes for epidermal growth factor and associated proteins that stimulate growth of cells. Those proteins are important for the movement of neural crest cells within an embryo. That finding seems to support a recent hypothesis that changes in neural crest cells could be responsible for domestication syndrome, physical traits, including floppy ears, spotted coats and juvenile faces, which accompany tameness in many domestic animals. © Society for Science & the Public 2000 - 2015.
Andrew Griffin Scientists have created an electronic memory cell that mimics the way that human brains work, potentially unlocking the possibility of the making bionic brains. The cell can process and store multiple bits of information, like the human brain. Scientists hope that developing it could make for artificial cells that simulate the brain’s processes, leading to treatments for neurological conditions and for replica brains that scientists can experiment on. The new cells have been likened to the difference between having an on-off light switch and a dimmer, or the difference between black and white pictures or those with full colour, including shade light and texture. While traditional memory cells for computers can only process one binary thing at a time, the new discovery allows for much more complex memory processes like those found in the brain. They are also able to retain previous information, allowing for artificial systems that have the extraordinary memory powers found in human beings. While the new discovery is a long way from leading to a bionic brain, the discovery is an important step towards the dense and fast memory cells that will be needed to imitate the human brain's processes. “This is the closest we have come to creating a brain-like system with memory that learns and stores analog information and is quick at retrieving this stored information,” Sharath Sriram, who led the project, said.
Aaron E. Carroll When I was a kid, my parents refused to let me drink coffee because they believed it would “stunt my growth.” It turns out, of course, that this is a myth. Studies have failed, again and again, to show that coffee or caffeine consumption are related to reduced bone mass or how tall people are. Coffee has long had a reputation as being unhealthy. But in almost every single respect that reputation is backward. The potential health benefits are surprisingly large. When I set out to look at the research on coffee and health, I thought I’d see it being associated with some good outcomes and some bad ones, mirroring the contradictory reports you can often find in the news media. This didn’t turn out to be the case. Just last year, a systematic review and meta-analysis of studies looking at long-term consumption of coffee and the risk of cardiovascular disease was published. The researchers found 36 studies involving more than 1,270,000 participants. The combined data showed that those who consumed a moderate amount of coffee, about three to five cups a day, were at the lowest risk for problems. Those who consumed five or more cups a day had no higher risk than those who consumed none. Of course, everything I’m saying here concerns coffee — black coffee. I am not talking about the mostly milk and sugar coffee-based beverages that lots of people consume. These could include, but aren’t limited to, things like a McDonald’s large mocha (500 calories, 17 grams of fat, 72 grams of carbohydrates), a Starbucks Venti White Chocolate Mocha (580 calories, 22 grams of fat, 79 grams of carbs), and a Large Dunkin’ Donuts frozen caramel coffee Coolatta (670 calories, 8 grams of fat, 144 grams of carbs). I won’t even mention the Cold Stone Creamery Gotta-Have-It-Sized Lotta Caramel Latte (1,790 calories, 90 grams of fat, 223 grams of carbs). Regular brewed coffee has 5 or fewer calories and no fat or carbohydrates. © 2015 The New York Times Company
Keyword: Drug Abuse
Link ID: 20908 - Posted: 05.12.2015
Robin McKie The European parliament will on Monday debate a call – backed by a petition signed by 1.2 million people – to scrap animal research in the EU. The proposal has alarmed scientists, who worked for six years to set up the 2010 European directive that controls animal experimentation and welfare in the EU. Researchers fear that the petition, which was drawn up by the Italian-based Stop Vivisection European citizens’ initiative, could sway many newly elected MEPs who would then press the European commission into scrapping the directive which, in the UK, is enshrined in an amendment to the 1986 Animals (Scientific Procedures) Act. “Without the directive, research using animals would be blocked and that would have terrible consequences,” said Nancy Lee, senior policy adviser at the Wellcome Trust. “New medicines for Alzheimer’s, heart disease, cancer and other conditions could no longer be tested. Similarly, new drugs for animals would also be blocked.” This view is backed by Dame Kay Davies, director of the MRC functional genomics unit at Oxford University. “Removal of the directive would be a significant step backwards both for animal welfare in the EU and for Europe’s leading role in advancing human and animal health,” she said in last week’s Nature. Other citizens’ initiatives, which require a minimum of a million signatures before they are heard by the European parliament, have included calls for improved water supplies and stricter speed limits in Europe.
Keyword: Animal Rights
Link ID: 20905 - Posted: 05.11.2015
By Lena H. Sun Most babies in the United States are born on a weekday, with the highest percentages delivered between 8 a.m. to 9 a.m., and from noon to 1 p.m., according to a report published Friday by the National Center for Health Statistics. That won't come as too much of a surprise to many pregnant women who had cesarean deliveries. Most births in the United States take place in hospitals. And as C-sections and induced labor have increased during the past few decades, more deliveries take place during the day, to maximize coordination and care with doctors and hospital staff. But what happens if the baby isn't born in the hospital, but in the home, where most out-of-hospital births occur? (Less than 2 percent of all U.S. births take place outside the hospital.) Those births were most likely to take place in the wee morning hours between 1 a.m. and 4:59 a.m., the report found. The reason: mother nature. "Where nature is taking its course, infants are more likely to be born when it's completely dark out," said T.J. Mathews, a demographer with the National Center for Health Statistics, part of the U.S. Centers for Disease Control and Prevention. Researchers think evolution may have something to do with making the middle of the night an optimal time for delivery. Say you were pregnant and part of a nomadic tribe. Having your baby in the middle of the day could mean the rest of the tribe leaves you behind as they move from place to place. "You probably bled to death," said Aaron Caughey, chairman of the Department of Obstetrics and Gynecology at Oregon Health & Science University's School of Medicine.
Keyword: Biological Rhythms
Link ID: 20904 - Posted: 05.09.2015
By Chris Cesare For bats, too many echoes can be like blurry vision. That’s because the nocturnal creatures navigate by bouncing ultrasonic sound off of their surroundings, a technique known as echolocation. In cramped spots, these sounds can reverberate, creating a noisy background that clouds the mammals’ sonic sight. Now, new research published online before print in the Proceedings of the National Academy of Sciences has discovered one way that bats might overcome this auditory ambush. Scientists found that the animals modify the width of their navigation pulses on the fly by adjusting the size of their mouth gape. The researchers used an array of cameras, flashes, and ultrasonic recorders to take snapshots of bats while they swooped down to take a sip at a desert pond in Israel. As the bats descended toward the confined banks of the pond, they opened their mouths wider to more tightly focus their sound pulses. As the bats left, they narrowed their mouths, projecting an ultrasonic beam up to four times wider than on the descending leg. These counterintuitive effects were due to diffraction, which causes sound waves traveling through a smaller hole to spread out more. The researchers repeated the experiment with captive bats and found the same effect, controlling for the possibility that they had observed a behavior tied to drinking. The team writes that these changes in gape allow the animals to “zoom in” on their view of an area, potentially reducing the amount of distracting echoes in a tight space. © 2015 American Association for the Advancement of Science
Link ID: 20901 - Posted: 05.09.2015
by Clare Wilson IT IS considered a soft drug, but increasing numbers of people are seeking help for cannabis addiction – and there's growing interest in finding ways to treat them. Paradoxically, the most promising treatment may be an extract of cannabis. Last month, researchers at the British Neuroscience Association meeting in Edinburgh, UK, described how the compound, called cannabidiol, helped one person who was severely addicted. A clinical trial is underway. Unlike most forms of drug addiction, there are no medical treatments to help people reduce their cannabis use. "Cannabis dependence is a huge unmet need with no pharmacological treatments," says Tom Freeman of University College London, who is involved in the trial. "It's vital we get one." A possible connection between smoking pot and schizophrenia is fairly well known, but the link is controversial and it affects only a small minority of users. Addiction seems to be a more common problem – yet is often overlooked. There is no universal definition of addiction or dependence. Someone is usually deemed to be addicted to a drug if they want to stop but cannot, or if it has a negative impact on their life. They would probably be experiencing withdrawal symptoms that make it hard to give up. In the case of heavy cannabis use, these can include anxiety and insomnia.
Keyword: Drug Abuse
Link ID: 20900 - Posted: 05.08.2015
By Rachel Feltman Animals didn't always have heads. We know that sometime during the Cambrian Period -- around 500 million years ago, as animals transitioned from the squishy likes of the penis worm to hard-bodied arthropods -- body segments started transitioning into something like the head/body differentiation we see today. But figuring out just how that transition went can be tricky. A study published on Thursday in Current Biology looks to one of the oldest-ever brain fossils for clues. Brains, being all squishy and stuff, aren't commonly found in fossilized form, especially not 500 million years after the fact. But the new study compares two specimens: A trilobite with a squishy body and Odaraia alata, a creature said to resemble a submarine. Cute, yeah? The Cambrian was such a great time. Lead author Javier Ortega-Hernández, a postdoctoral researcher from Cambridge's Department of Earth Sciences, found that the front portions of both creatures' brains had nerve connections to their eye stalks and a hard plate called the anterior sclerite. In modern arthropods, that brain region controls the eyes. Ortega-Hernández believes that this anterior sclerite was a bridge between ancient arthropods and more modern ones. Anomalocaridids, which lived at the same time but looked very different, have a plate that Ortega-Hernández thinks came from the same ancestral anatomy that went on to form anterior sclerites in the animals he examined (and, eventually, a more modern head structure today).
Link ID: 20899 - Posted: 05.08.2015
by Clare Wilson WHAT is it like to be a bat? It's a question philosophers interested in consciousness like to ponder. Yet a few people already have something of a bat's world view. Brian Borowski, a 59-year-old Canadian who was born blind, began teaching himself to echolocate aged 3. He clicks with his tongue or snaps his fingers as he moves about, unconsciously decoding the echoes. Although many blind people get information from sounds around them, few turn this into a supersense by making sounds to help themselves get around. "When I'm walking down a sidewalk and I pass trees, I can hear the tree: the vertical trunk of the tree and maybe the branches above me," says Borowski. "I can hear a person in front of me and go around them." Borowski, who works as a programmer at Western University in London, Ontario, suspects he experiences "images" in a similar way to people who can see, just with less detail. "I store maps of information in my head and I compare what I have in my memory with what I'm hearing around me," he says. "I am matching images of some sort." This probably isn't too far from the truth – we know from brain scans of Borowski and another echolocator that the strategy co-opts the same parts of the brain that usually deal with visual information. For his latest scientific collaboration, he helped a team of researchers to explore how well echolocators can determine the relative sizes and distances of objects. © Copyright Reed Business Information Ltd
Link ID: 20898 - Posted: 05.08.2015
By Melissa Healy contact the reporter Schizophrenia is one of psychiatry's most puzzling afflictions, with a complex of symptoms that goes far beyond its hallmark hallucinations and delusional thinking. But new research has found connections among several of schizophrenia's peculiar collection of symptoms -- including agitation and memory problems -- and linked them to a single genetic variant among the hundreds thought to heighten risk of the disorder. The findings offer new insights into the molecular basis for schizophrenia and could lead to treatments for the disease that are more targeted and more comprehensive. Published Monday in the journal Nature Neuroscience, the study looks at how a gene variant called Arp2/3 contributes to psychosis, agitation and problems of short- and long-term memory. Mice that were genetically modified to lack the Arp2/3 gene variant showed all three symptoms (although to measure psychosis in mice, scientists looked instead for an abnormal startle response that is also seen in humans in the grips of psychosis). The study's authors, led by Duke University neurobiologist Scott Soderling, then dug below those behaviors to see whether brain abnormalities linked to such behaviors had anything in common. Mice that lacked the Arp2/3 gene variant, they discovered, had not only symptoms of schizophrenia, but also several of the underlying brain abnormalities most closely linked to psychosis, agitation and memory problems seen in those with schizophrenia.
Link ID: 20895 - Posted: 05.06.2015
By Jocelyn Kaiser One of the most heralded successes of gene therapy may not be the permanent fix that many had hoped. Leaders of two clinical trials report this week that a treatment that restored some vision to blind patients begins to fade within a few years. A third group, however, says their patients, who received a different version of the therapy, are retaining their improved vision, and a company is moving ahead with efforts to gain regulatory approval for their treatment. It is not a huge surprise that the treatment effects may not last, says eye disease researcher Mark Pennesi of Oregon Health & Science University in Portland, who is running a similar trial. “These are complex diseases and everything that’s been done is sort of first generation,” he says. “The fact that there was biological activity at all is a milestone.” At issue is gene therapy for a rare form of inherited blindness known as Leber’s congenital amaurosis (LCA) that results in complete vision loss by about age 40. About 10% of cases are due to a mutation in retinal pigment epithelium 65 (RPE65), a gene that codes for an enzyme that helps retinal cells make rhodopsin. The pigment is needed by photoreceptor cells—the retina’s light-sending rods and cones—and when RPE65 is mutated, the photoreceptor cells gradually die. In 2007, in the first-ever effort to use gene therapy to treat people with blindness, three separate teams in the United States and the United Kingdom launched clinical trials for the RPE65 type of LCA. A surgeon injected one eye of each patient with a solution containing a harmless virus that ferried a good copy of RPE65 into retinal cells. © 2015 American Association for the Advancement of Science
Link ID: 20892 - Posted: 05.05.2015
By Jonathan Webb Science reporter, BBC News Scientists have stumbled upon one of the secrets behind the big gulps of the world's biggest whales: the nerves in their jaws are stretchy. Rorquals, a family that includes blue and humpback whales, feed by engulfing huge volumes of water and food, sometimes bigger than themselves. Researchers made the discovery by inadvertently stretching a thick cable they found in the jaw of a fin whale. Most nerves are fragile and inelastic, so this find is first for vertebrates. The work is reported in the journal Current Biology. A Canadian research team had travelled to Iceland to investigate some of these whales' other anatomical adaptations to "lunge feeding" - things like their muscles, or the remarkable sensory organ in their jaws, discovered in 2012. They were working with specimens in collaboration with commercial whalers. "It's probably one of the only places in the world where you can do this sort of work, because these animals are so huge that even getting in through the skin is something you can't do without having heavy machinery around," said Prof Wayne Vogl, an anatomist at the University of British Columbia and the study's first author. When you are working with a 20m fin whale, it's important to have the right equipment, he said. "If a heart falls on you, it could kill you." © 2015 BBC.
James Gorman If modern science is right, the great mystery of embryonic development is less about how life unfolds, and more about how it folds. Embryos of many organisms grow from two cells to four, then eight, and so on until there are thousands in a kind of ball. Then sheets of cells start to make folds or furrows as the basic shape of the creature — fly or fish or human — begins to emerge. One of the most striking examples is a moment in the development of Volvox, a kind of algae that forms one of the simplest multicellular organisms. When it is a sphere of a few thousand cells, it reaches adult size, but not adult shape. So it turns itself inside out. Scientists at the University of Cambridge in England have made a time-lapse recording of the process that shows it in three dimensions for the first time and has enough detail that researchers can check their mathematical descriptions of the transformation. © 2015 The New York Times Company
Keyword: Development of the Brain
Link ID: 20888 - Posted: 05.05.2015