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Javier E

The Lasting Lessons of John Conway's Game of Life - The New York Times - 0 views

www.nytimes.com/...math-conway-game-of-life.html

emergent life game lessons programming software simulation chaos

shared by Javier E on 29 Dec 20 - No Cached
  • “Because of its analogies with the rise, fall and alterations of a society of living organisms, it belongs to a growing class of what are called ‘simulation games,’” Mr. Gardner wrote when he introduced Life to the world 50 years ago with his October 1970 column.
  • The Game of Life motivated the use of cellular automata in the rich field of complexity science, with simulations modeling everything from ants to traffic, clouds to galaxies. More trivially, the game attracted a cult of “Lifenthusiasts,” programmers who spent a lot of time hacking Life — that is, constructing patterns in hopes of spotting new Life-forms.
  • The tree of Life also includes oscillators, such as the blinker, and spaceships of various sizes (the glider being the smallest).
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  • Patterns that didn’t change one generation to the next, Dr. Conway called still lifes — such as the four-celled block, the six-celled beehive or the eight-celled pond. Patterns that took a long time to stabilize, he called methuselahs.
  • The second thing Life shows us is something that Darwin hit upon when he was looking at Life, the organic version. Complexity arises from simplicity!
  • I first encountered Life at the Exploratorium in San Francisco in 1978. I was hooked immediately by the thing that has always hooked me — watching complexity arise out of simplicity.
  • Life shows you two things. The first is sensitivity to initial conditions. A tiny change in the rules can produce a huge difference in the output, ranging from complete destruction (no dots) through stasis (a frozen pattern) to patterns that keep changing as they unfold.
  • Life shows us complex virtual “organisms” arising out of the interaction of a few simple rules — so goodbye “Intelligent Design.”
  • I’ve wondered for decades what one could learn from all that Life hacking. I recently realized it’s a great place to try to develop “meta-engineering” — to see if there are general principles that govern the advance of engineering and help us predict the overall future trajectory of technology.
  • Melanie Mitchell— Professor of complexity, Santa Fe Institute
  • Given that Conway’s proof that the Game of Life can be made to simulate a Universal Computer — that is, it could be “programmed” to carry out any computation that a traditional computer can do — the extremely simple rules can give rise to the most complex and most unpredictable behavior possible. This means that there are certain properties of the Game of Life that can never be predicted, even in principle!
  • I use the Game of Life to make vivid for my students the ideas of determinism, higher-order patterns and information. One of its great features is that nothing is hidden; there are no black boxes in Life, so you know from the outset that anything that you can get to happen in the Life world is completely unmysterious and explicable in terms of a very large number of simple steps by small items.
  • In Thomas Pynchon’s novel “Gravity’s Rainbow,” a character says, “But you had taken on a greater and more harmful illusion. The illusion of control. That A could do B. But that was false. Completely. No one can do. Things only happen.”This is compelling but wrong, and Life is a great way of showing this.
  • In Life, we might say, things only happen at the pixel level; nothing controls anything, nothing does anything. But that doesn’t mean that there is no such thing as action, as control; it means that these are higher-level phenomena composed (entirely, with no magic) from things that only happen.
  • Stephen Wolfram— Scientist and C.E.O., Wolfram Research
  • Brian Eno— Musician, London
  • Bert Chan— Artificial-life researcher and creator of the continuous cellular automaton “Lenia,” Hong Kong
  • it did have a big impact on beginner programmers, like me in the 90s, giving them a sense of wonder and a kind of confidence that some easy-to-code math models can produce complex and beautiful results. It’s like a starter kit for future software engineers and hackers, together with Mandelbrot Set, Lorenz Attractor, et cetera.
  • if we think about our everyday life, about corporations and governments, the cultural and technical infrastructures humans built for thousands of years, they are not unlike the incredible machines that are engineered in Life.
  • In normal times, they are stable and we can keep building stuff one component upon another, but in harder times like this pandemic or a new Cold War, we need something that is more resilient and can prepare for the unpreparable. That would need changes in our “rules of life,” which we take for granted.
  • Rudy Rucker— Mathematician and author of “Ware Tetralogy,” Los Gatos, Calif.
  • That’s what chaos is about. The Game of Life, or a kinky dynamical system like a pair of pendulums, or a candle flame, or an ocean wave, or the growth of a plant — they aren’t readily predictable. But they are not random. They do obey laws, and there are certain kinds of patterns — chaotic attractors — that they tend to produce. But again, unpredictable is not random. An important and subtle distinction which changed my whole view of the world.
  • William Poundstone— Author of “The Recursive Universe: Cosmic Complexity and the Limits of Scientific Knowledge,” Los Angeles, Calif.
  • The Game of Life’s pulsing, pyrotechnic constellations are classic examples of emergent phenomena, introduced decades before that adjective became a buzzword.
  • Fifty years later, the misfortunes of 2020 are the stuff of memes. The biggest challenges facing us today are emergent: viruses leaping from species to species; the abrupt onset of wildfires and tropical storms as a consequence of a small rise in temperature; economies in which billions of free transactions lead to staggering concentrations of wealth; an internet that becomes more fraught with hazard each year
  • Looming behind it all is our collective vision of an artificial intelligence-fueled future that is certain to come with surprises, not all of them pleasant.
  • The name Conway chose — the Game of Life — frames his invention as a metaphor. But I’m not sure that even he anticipated how relevant Life would become, and that in 50 years we’d all be playing an emergent game of life and death.
anonymous

Inside the Science of Memory | Johns Hopkins Medicine - 0 views

www.hopkinsmedicine.org/...inside-the-science-of-memory

shared by anonymous on 03 Nov 20 - No Cached
  • “Memories are who we are,” says Huganir. “But making memories is also a biological process.”
  • This process raises many questions. How does the process affect our brain? How do experiences and learning change the connections in our brains and create memories?
  • Memory: It’s All About Connections
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  • When we learn something—even as simple as someone’s name—we form connections between neurons in the brain. These synapses create new circuits between nerve cells, essentially remapping the brain.
  • The sheer number of possible connections gives the brain unfathomable flexibility—each of the brain’s 100 billion nerve cells can have 10,000 connections to other nerve cells.
  • Huganir and his team discovered that when mice are exposed to traumatic events, the level of neuronal receptors for glutamate increases at synapses in the amygdala, the fear center of the brain, and encodes the fear associated with the memory. Removing those receptors, however, reduces the strength of these connections, essentially erasing the fear component of the trauma but leaving the memory.
  • Now Huganir and his lab are developing drugs that target those receptors. The hope is that inactivating the receptors could help people with post-traumatic stress syndrome by reducing the fear associated with a traumatic memory, while strengthening them could improve learning, particularly in people with cognitive dysfunction or Alzheimer’s disease.
  • Dementia (di-men-sha): A loss of brain function that can be caused by a variety of disorders affecting the brain. Symptoms include forgetfulness, impaired thinking and judgment, personality changes, agitation and loss of emotional control. Alzheimer’s disease, Huntington’s disease and inadequate blood flow to the brain can all cause dementia. Most types of dementia are irreversible.
  • Post-traumatic stress disorder (PTSD): A disorder in which your “fight or flight,” or stress, response stays switched on, even when you have nothing to flee or battle. The disorder usually develops after an emotional or physical trauma, such as a mugging, physical abuse or a natural disaster. Symptoms include nightmares, insomnia, angry outbursts, emotional numbness, and physical and emotional tension.
runlai_jiang

Impossible Colors and How to See Them - 0 views

www.thoughtco.com/le-colors-introduction-4152091

shared by runlai_jiang on 15 Jan 18 - No Cached
  • Impossible Colors and How to See Them
  • How Impossible Colors Work Basically, the human eye has three types of cone cells that register color that work in an antagonistic fashion:Blue versus yellowRed versus greenLight versus darkThere is overlap between the wavelengths of light covered by the cone cells, so you see more than just blue, yellow, red, and green. White, for example, is not a wavelength of light, yet the human eye perceives it as a mixture of different spectral colors. Because of the opponent process, you can't see both blue and yellow at the same time, nor red and green. These combinations are so-called impossible colors.
  • Chimerical Colors Hyperbolic colors may be seen by staring at a color and then viewing the afterimage on the complementary color opposite it on the color wheel. Dave King / Getty Images
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  • While you can't ordinarily see both red and green or both blue and yellow, visual scientist Hewitt Crane and his colleague Thomas Piantanida published a paper in Science claiming such perception was possible. In their 1983 paper "On Seeing Reddish Green and Yellowish Blue" they claimed volunteers viewing adjacent red and green stripes could see reddish green, while viewers of adjacent yellow and blue stripes could see yellowish blue. The researchers used an eye tracker to hold the
  • The impossible colors reddish green and yellowish blue are imaginary colors that do not occur in the light spectrum. Another type of imaginary color is a chimerical color. A chimerical color is seen by looking at a color until the cone cells are fatigued and then looking at a different color. This produces an afterimage perceived by the brain, not the eyes.Examples of chimerical colors include:Self-luminous colors: Self-luminous colors appear to glow even though no light is emitted. An
  • Stygian colors: Stygian colors are dark and supersaturated. For example, "stygian blue" may be seen by staring at bright yellow and then looking at black. The normal afterimage is dark blue. When viewed against black, the resulting blue is as dark as black, yet colored. Stygian colors appear on black because certain neurons only fire signals in the dark.Hyperbolic colors:
  • Impossible colors like reddish green or yellowish blue are trickier to see. To try to see these colors, put a yellow object and blue object right next to each other and cross your eyes so that the two objects overlap. The same procedure works for green and red. The overlapping region may appear to be a mix of the two colors (i.e., green for blue and yellow, brown for red and green), a field of dots of the component colors, or an unfamiliar color that is both red/green or yellow/blue at once!
krystalxu

5 things you should know about how your brain learns | Voices From Campus News for Coll... - 0 views

college.usatoday.com/...5-way-your-brain-learns

brain science memory working memory science knowledge

shared by krystalxu on 07 Oct 17 - No Cached
  • how your brain learns
  • Learning builds on prior knowledge
  • The human brain consists of special cells called neurons
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  • these brain fibers grow
  • fibers connect your brain cells to one another at contact points called synapses.
  • Practice leads to stronger connections in the brain
  • brain fibers can only grow from existing brain fibers.
  • build on information that is already stored in the brain.
  • having a strong understanding of the foundational content in a given subject is essential
  • The larger your brain fibers grow, and the more brain cells they connect, the more information can be stored in your brain.
  • With enough practice, these thickened brain fibers will eventually form double connections to one another.
  • causes your dendrites to grow thicker and to coat themselves with a fatty layer.
  • The fatty coating on brain fibers also speeds up your brain’s ability to process information.
  • solidify that information or ability in your brain more permanently.
  • the brain grows fibers that relate to what you are practicing.
  • , but to also perform that skill yourself. This will help you truly learn it.
  • its general limit is five to seven items.
  • memory can be improved by taking proper care of your brain and body.
  • grouping items together before you try to memorize them.
  • a routine lack of sleep can have detrimental impacts on your health.
  • sleep deprivation can drastically diminish your brain’s ability to take in new information.
  • it is extremely important to get a full night’s rest within the first 30 hours of learning new knowledge.
johnsonel7

Sensory perception | Science Features | Naked Scientists - 0 views

www.thenakedscientists.com/...derstanding-sensory-perception

sense perception brain science

shared by johnsonel7 on 01 Nov 19 - No Cached
  • Deciphering how the brain processes sight and hearing could have implications for how we understand and treat conditions such as dyslexia, autism and schizophrenia.
  • schizophrenia
  • Through a project called SENSOCOM, she is exploring how sensory perception affects communication, focusing on the brain’s deep subcortical structures.By doing this, she and her team are exploring a part of the brain traditionally excluded by research trying to understand communication impairments found in autism spectrum disorder and dyslexia, conditions which affect around 53 million people in Europe.
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  • To do this they have been focusing on the sensory pathways linked to these deep structures. She and her group discovered that adults with dyslexia have weaker pathway connections between a visual subcortical structure (the left visual thalamus) with an area of the cortex called V5/MT, which is critical for the perception of visual motion. In the auditory mode, there was a similar finding. The team discovered weaker connections between the left auditory thalamus and a cortex structure linked to auditory motion, which is important for speech perception. These connections could therefore be important for reading and for predicting reading skill, according to Dr von Kriegstein.
  • So how might this translate into helping people with dyslexia? This is basic science, says Prof. von Kriegstein, so first it’s crucial to understand the mechanisms behind communications disorders before developing therapy training tools, although she is optimistic these could lie within reach.
  • The way the brain encodes information and in turn directs perception of that sensory experience is a highly variable process.
  • The sensory overload or distorted and heightened perceptions described by schizophrenia patients, for instance, could relate to these deficits. Sensory dysfunction has also been linked to delusions and hallucinations as well as difficulties with attention and reading the emotions or tone of others – all of which can affect social interaction.
  • According to Dr Fellin, decreased connectivity between nerve cells (neurons) appears to play an important role in the progression of schizophrenia. So far, Dr Fellin and his group have identified which specific neurons influence sensory responses in mouse studies, but not yet in animal models of schizophrenia, with similar investigations in glial cells  - the supporting cells of the nervous system.
anniina03

Schizophrenia study finds evidence of reduced links between brain cells | Science | The... - 0 views

www.theguardian.com/...renia-reduced-brain-cell-links

science research brain science psychology

shared by anniina03 on 14 Jan 20 - No Cached
  • A groundbreaking brain-scanning technique has uncovered evidence that suggests schizophrenia is linked to a loss of connections between brain cells.
  • They used a tracer that binds to the protein and which emits a signal that can be picked up by a PET brain scan, which provided an indirect measure of the density of connections. The team scanned 18 adults with schizophrenia and compared them with 18 people without the condition. They found that levels of SV2A were significantly lower in the front of the brain – the region involved in planning – in people with schizophrenia.
manhefnawi

Scientists Grow Working Human Brain Circuits | Mental Floss - 0 views

mentalfloss.com/...w-working-human-brain-circuits

Brain Science

shared by manhefnawi on 14 Jun 18 - No Cached
  • Scientists have been culturing brain cells in the lab for some time now. But previous projects have produced only flat sheets of cells and tissue, which can’t really come close to recreating the three-dimensional conditions inside our heads. The Stanford researchers were especially interested in the way brain cells in a developing fetus can join up together to create networks.
manhefnawi

See these first-of-a-kind views of living human nerve cells | Science News - 0 views

www.sciencenews.org/...views-living-human-nerve-cells

Human Brain

shared by manhefnawi on 14 Jun 18 - No Cached
  • The human brain is teeming with diversity. By plucking out delicate, live tissue during neurosurgery and then studying the resident cells, researchers have revealed a partial cast of neural characters that give rise to our thoughts, dreams and memories. 
manhefnawi

Human brains make new nerve cells - and lots of them - well into old age | Science News - 0 views

www.sciencenews.org/...lls-and-lots-them-well-old-age

Neurology

shared by manhefnawi on 14 Jun 18 - No Cached
  • Your brain might make new nerve cells well into old age.
  • Understanding how healthy brains change over time is important for researchers untangling the ways that conditions like depression, stress and memory loss affect older brains.
  • When it comes to studying neurogenesis in humans, “the devil is in the details,” says Jonas Frisén, a neuroscientist at the Karolinska Institute in Stockholm who was not involved in the new research. Small differences in methodology — such as the way brains are preserved or how neurons are counted — can have a big impact on the results, which could explain the conflicting findings. The new paper “is the most rigorous study yet,” he says.
Javier E

The new science of death: 'There's something happening in the brain that makes no sense... - 0 views

www.theguardian.com/...iousness-near-death-experience

death science brain science research psychology

shared by Javier E on 04 Apr 24 - No Cached
  • Jimo Borjigin, a professor of neurology at the University of Michigan, had been troubled by the question of what happens to us when we die. She had read about the near-death experiences of certain cardiac-arrest survivors who had undergone extraordinary psychic journeys before being resuscitated. Sometimes, these people reported travelling outside of their bodies towards overwhelming sources of light where they were greeted by dead relatives. Others spoke of coming to a new understanding of their lives, or encountering beings of profound goodness
  • Borjigin didn’t believe the content of those stories was true – she didn’t think the souls of dying people actually travelled to an afterworld – but she suspected something very real was happening in those patients’ brains. In her own laboratory, she had discovered that rats undergo a dramatic storm of many neurotransmitters, including serotonin and dopamine, after their hearts stop and their brains lose oxygen. She wondered if humans’ near-death experiences might spring from a similar phenomenon, and if it was occurring even in people who couldn’t be revived
  • when she looked at the scientific literature, she found little enlightenment. “To die is such an essential part of life,” she told me recently. “But we knew almost nothing about the dying brain.” So she decided to go back and figure out what had happened inside the brains of people who died at the University of Michigan neurointensive care unit.
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  • Since the 1960s, advances in resuscitation had helped to revive thousands of people who might otherwise have died. About 10% or 20% of those people brought with them stories of near-death experiences in which they felt their souls or selves departing from their bodies
  • According to several international surveys and studies, one in 10 people claims to have had a near-death experience involving cardiac arrest, or a similar experience in circumstances where they may have come close to death. That’s roughly 800 million souls worldwide who may have dipped a toe in the afterlife.
  • In the 1970s, a small network of cardiologists, psychiatrists, medical sociologists and social psychologists in North America and Europe began investigating whether near-death experiences proved that dying is not the end of being, and that consciousness can exist independently of the brain. The field of near-death studies was born.
  • in 1975, an American medical student named Raymond Moody published a book called Life After Life.
  • Meanwhile, new technologies and techniques were helping doctors revive more and more people who, in earlier periods of history, would have almost certainly been permanently deceased.
  • “We are now at the point where we have both the tools and the means to scientifically answer the age-old question: What happens when we die?” wrote Sam Parnia, an accomplished resuscitation specialist and one of the world’s leading experts on near-death experiences, in 2006. Parnia himself was devising an international study to test whether patients could have conscious awareness even after they were found clinically dead.
  • Borjigin, together with several colleagues, took the first close look at the record of electrical activity in the brain of Patient One after she was taken off life support. What they discovered – in results reported for the first time last year – was almost entirely unexpected, and has the potential to rewrite our understanding of death.
  • “I believe what we found is only the tip of a vast iceberg,” Borjigin told me. “What’s still beneath the surface is a full account of how dying actually takes place. Because there’s something happening in there, in the brain, that makes no sense.”
  • Over the next 30 years, researchers collected thousands of case reports of people who had had near-death experiences
  • Moody was their most important spokesman; he eventually claimed to have had multiple past lives and built a “psychomanteum” in rural Alabama where people could attempt to summon the spirits of the dead by gazing into a dimly lit mirror.
  • near-death studies was already splitting into several schools of belief, whose tensions continue to this day. One influential camp was made up of spiritualists, some of them evangelical Christians, who were convinced that near-death experiences were genuine sojourns in the land of the dead and divine
  • It is no longer unheard of for people to be revived even six hours after being declared clinically dead. In 2011, Japanese doctors reported the case of a young woman who was found in a forest one morning after an overdose stopped her heart the previous night; using advanced technology to circulate blood and oxygen through her body, the doctors were able to revive her more than six hours later, and she was able to walk out of the hospital after three weeks of care
  • The second, and largest, faction of near-death researchers were the parapsychologists, those interested in phenomena that seemed to undermine the scientific orthodoxy that the mind could not exist independently of the brain. These researchers, who were by and large trained scientists following well established research methods, tended to believe that near-death experiences offered evidence that consciousness could persist after the death of the individua
  • Their aim was to find ways to test their theories of consciousness empirically, and to turn near-death studies into a legitimate scientific endeavour.
  • Finally, there emerged the smallest contingent of near-death researchers, who could be labelled the physicalists. These were scientists, many of whom studied the brain, who were committed to a strictly biological account of near-death experiences. Like dreams, the physicalists argued, near-death experiences might reveal psychological truths, but they did so through hallucinatory fictions that emerged from the workings of the body and the brain.
  • Between 1975, when Moody published Life After Life, and 1984, only 17 articles in the PubMed database of scientific publications mentioned near-death experiences. In the following decade, there were 62. In the most recent 10-year span, there were 221.
  • Today, there is a widespread sense throughout the community of near-death researchers that we are on the verge of great discoveries
  • “We really are in a crucial moment where we have to disentangle consciousness from responsiveness, and maybe question every state that we consider unconscious,”
  • “I think in 50 or 100 years time we will have discovered the entity that is consciousness,” he told me. “It will be taken for granted that it wasn’t produced by the brain, and it doesn’t die when you die.”
  • it is in large part because of a revolution in our ability to resuscitate people who have suffered cardiac arrest
  • In his book, Moody distilled the reports of 150 people who had had intense, life-altering experiences in the moments surrounding a cardiac arrest. Although the reports varied, he found that they often shared one or more common features or themes. The narrative arc of the most detailed of those reports – departing the body and travelling through a long tunnel, having an out-of-body experience, encountering spirits and a being of light, one’s whole life flashing before one’s eyes, and returning to the body from some outer limit – became so canonical that the art critic Robert Hughes could refer to it years later as “the familiar kitsch of near-death experience”.
  • Loss of oxygen to the brain and other organs generally follows within seconds or minutes, although the complete cessation of activity in the heart and brain – which is often called “flatlining” or, in the case of the latter, “brain death” – may not occur for many minutes or even hours.
  • That began to change in 1960, when the combination of mouth-to-mouth ventilation, chest compressions and external defibrillation known as cardiopulmonary resuscitation, or CPR, was formalised. Shortly thereafter, a massive campaign was launched to educate clinicians and the public on CPR’s basic techniques, and soon people were being revived in previously unthinkable, if still modest, numbers.
  • scientists learned that, even in its acute final stages, death is not a point, but a process. After cardiac arrest, blood and oxygen stop circulating through the body, cells begin to break down, and normal electrical activity in the brain gets disrupted. But the organs don’t fail irreversibly right away, and the brain doesn’t necessarily cease functioning altogether. There is often still the possibility of a return to life. In some cases, cell death can be stopped or significantly slowed, the heart can be restarted, and brain function can be restored. In other words, the process of death can be reversed.
  • In a medical setting, “clinical death” is said to occur at the moment the heart stops pumping blood, and the pulse stops. This is widely known as cardiac arrest
  • In 2019, a British woman named Audrey Schoeman who was caught in a snowstorm spent six hours in cardiac arrest before doctors brought her back to life with no evident brain damage.
  • That is a key tenet of the parapsychologists’ arguments: if there is consciousness without brain activity, then consciousness must dwell somewhere beyond the brain
  • Some of the parapsychologists speculate that it is a “non-local” force that pervades the universe, like electromagnetism. This force is received by the brain, but is not generated by it, the way a television receives a broadcast.
  • In order for this argument to hold, something else has to be true: near-death experiences have to happen during death, after the brain shuts down
  • To prove this, parapsychologists point to a number of rare but astounding cases known as “veridical” near-death experiences, in which patients seem to report details from the operating room that they might have known only if they had conscious awareness during the time that they were clinically dead.
  • At the very least, Parnia and his colleagues have written, such phenomena are “inexplicable through current neuroscientific models”. Unfortunately for the parapsychologists, however, none of the reports of post-death awareness holds up to strict scientific scrutiny. “There are many claims of this kind, but in my long decades of research into out-of-body and near-death experiences I never met any convincing evidence that this is true,”
  • In other cases, there’s not enough evidence to prove that the experiences reported by cardiac arrest survivors happened when their brains were shut down, as opposed to in the period before or after they supposedly “flatlined”. “So far, there is no sufficiently rigorous, convincing empirical evidence that people can observe their surroundings during a near-death experience,”
  • The parapsychologists tend to push back by arguing that even if each of the cases of veridical near-death experiences leaves room for scientific doubt, surely the accumulation of dozens of these reports must count for something. But that argument can be turned on its head: if there are so many genuine instances of consciousness surviving death, then why should it have so far proven impossible to catch one empirically?
  • The spiritualists and parapsychologists are right to insist that something deeply weird is happening to people when they die, but they are wrong to assume it is happening in the next life rather than this one. At least, that is the implication of what Jimo Borjigin found when she investigated the case of Patient One.
  • Given the levels of activity and connectivity in particular regions of her dying brain, Borjigin believes it’s likely that Patient One had a profound near-death experience with many of its major features: out-of-body sensations, visions of light, feelings of joy or serenity, and moral re-evaluations of one’s life. Of course,
  • “As she died, Patient One’s brain was functioning in a kind of hyperdrive,” Borjigin told me. For about two minutes after her oxygen was cut off, there was an intense synchronisation of her brain waves, a state associated with many cognitive functions, including heightened attention and memory. The synchronisation dampened for about 18 seconds, then intensified again for more than four minutes. It faded for a minute, then came back for a third time.
  • n those same periods of dying, different parts of Patient One’s brain were suddenly in close communication with each other. The most intense connections started immediately after her oxygen stopped, and lasted for nearly four minutes. There was another burst of connectivity more than five minutes and 20 seconds after she was taken off life support. In particular, areas of her brain associated with processing conscious experience – areas that are active when we move through the waking world, and when we have vivid dreams – were communicating with those involved in memory formation. So were parts of the brain associated with empathy. Even as she slipped irre
  • something that looked astonishingly like life was taking place over several minutes in Patient One’s brain.
  • Although a few earlier instances of brain waves had been reported in dying human brains, nothing as detailed and complex as what occurred in Patient One had ever been detected.
  • In the moments after Patient One was taken off oxygen, there was a surge of activity in her dying brain. Areas that had been nearly silent while she was on life support suddenly thrummed with high-frequency electrical signals called gamma waves. In particular, the parts of the brain that scientists consider a “hot zone” for consciousness became dramatically alive. In one section, the signals remained detectable for more than six minutes. In another, they were 11 to 12 times higher than they had been before Patient One’s ventilator was removed.
  • “The brain, contrary to everybody’s belief, is actually super active during cardiac arrest,” Borjigin said. Death may be far more alive than we ever thought possible.
  • “The brain is so resilient, the heart is so resilient, that it takes years of abuse to kill them,” she pointed out. “Why then, without oxygen, can a perfectly healthy person die within 30 minutes, irreversibly?”
  • Evidence is already emerging that even total brain death may someday be reversible. In 2019, scientists at Yale University harvested the brains of pigs that had been decapitated in a commercial slaughterhouse four hours earlier. Then they perfused the brains for six hours with a special cocktail of drugs and synthetic blood. Astoundingly, some of the cells in the brains began to show metabolic activity again, and some of the synapses even began firing.
oliviaodon

Exercise Boosts Brain Health, but Is There a Downside? - The New York Times - 0 views

well.blogs.nytimes.com/...health-but-is-there-a-downside

brain science

shared by oliviaodon on 23 Oct 16 - No Cached
  • A 2014 experiment with mice first raised that worrying idea, finding that the more the animals exercised, the worse their long-term memories became.
  • Study after study in animals has shown that exercise, especially aerobic activities like running, can double or triple the number of new cells in the hippocampus, compared with the number in animals that do not exercise, and that these new cells translate into a significantly heightened ability to learn new skills. Animals that run, in essence, become brighter than those that do not. But most of these studies of exercise and neurogenesis have examined the effects on learning and short-term memory.
  • But for now, he believes that the available evidence suggests that, unless you are a mouse, working out is going to be “quite beneficial” for your brain.
Ellie McGinnis

The Mammoth Cometh - NYTimes.com - 2 views

www.nytimes.com/...the-mammoth-cometh.html

research science technology ethics conservation

shared by Ellie McGinnis on 27 Feb 14 - No Cached
  • Brand helped to establish in 1996 to support projects designed to inspire “long-term responsibility.”
  • The theme of the talk was “Is Mass Extinction of Life on Earth Inevitable?”
  • the resurrection of extinct species, like the woolly mammoth, aided by new genomic technologies developed by the Harvard molecular biologist George Church.
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  • Just as the loss of a species decreases the richness of an ecosystem, the addition of new animals could achieve the opposite effect.
  • National Geographic Society hosted a larger conference to debate the scientific and ethical questions raised by the prospect of “de-extinction.
  • “De-extinction went from concept to potential reality right before our eyes,
  • “This may be the biggest attraction and possibly the biggest benefit of de-extinction. It would surely be very cool to see a living woolly mammoth.”
  • less scientific, if more persuasive, argument was advanced by the ethicist Hank Greely and the law professor Jacob Sherkow, both of Stanford. De-extinction should be pursued, they argued in a paper published in Science, because it would be really
  • They will replace chunks of band-tailed-pigeon DNA with synthesized chunks of passenger-pigeon DNA, until the cell’s genome matches their working passenger-pigeon genome.
  • Scientists predict that changes made by human beings to the composition of the atmosphere could kill off a quarter of the planet’s mammal species, a fifth of its reptiles and a sixth of its birds by 2050
  • This cloning method, called somatic cell nuclear transfer, can be used only on species for which we have cellular material.
  • There is a shortcut. The genome of a closely related species will have a high proportion of identical DNA, so it can serve as a blueprint, or “scaffold.”
  • By comparing the fragments of passenger-pigeon DNA with the genomes of similar species, researchers can assemble an approximation of an actual passenger-pigeon genome.
  • “We’ve framed it in terms of conservation,”
  • the genome will have to be inscribed into a living cell.
  • As with any translation, there may be errors of grammar, clumsy phrases and perhaps a few missing passages, but the book will be legible. It should, at least, tell a good story.
  • MAGE (Multiplex Automated Genome Engineering). MAGE is nicknamed the “evolution machine” because it can introduce the equivalent of millions of years of genetic mutations within minutes
  • Developmental and behavioral biologists would take over, just in time to answer some difficult questions. Chicks imitate their parents’ behavior. How do you raise a passenger pigeon without parents of its own species? And how do you train band-tailed pigeons to nurture the strange spawn that emerge from their eggs; chicks that, to them, might seem monstrous: an avian Rosemary’s Baby?
  • For endangered species with tiny populations, scientists would introduce genetic diversity to offset inbreeding.
  • They will try to alter the birds’ diets, migration habits and environment. The behavior of each subsequent generation will more closely resemble that of their genetic cousins.
  • “There’s always this fear that somehow, if we do it, we’re going to accidentally make something horrible, because only nature can really do it right. But nature is totally random. Nature makes monsters. Nature makes threats. Many of the things that are most threatening to us are a product of nature. Revive & Restore is not going to tip the balance in any way.”
  • For species threatened by contagion, an effort would be made to fortify their DNA with genes that make them disease-resistant
  • This optimistic, soft-focus fantasy of de-extinction, while thrilling to Ben Novak, is disturbing to many conservation biologists, who consider it a threat to their entire discipline and even to the environmental movement.
  • The first question posed by conservationists addresses the logic of bringing back an animal whose native habitat has disappeared. Why go through all the trouble just to have the animal go extinct all over again?
  • There is also anxiety about disease
  • “If you recreate a species genetically and release it, and that genotype is based on a bird from a 100-year-old environment, you probably will increase risk.”
  • The scientific term for this type of genetic intervention is “facilitated adaptation.”
  • De-extinction also poses a rhetorical threat to conservation biologists. The specter of extinction has been the conservation movement’s most powerful argument. What if extinction begins to be seen as a temporary inconvenience?
  • De-extinction suggests that we can technofix our way out of environmental issues generally, and that’s very, very bad.
  • How will we decide which species to resurrect?
  • Philip Seddon recently published a 10-point checklist to determine the suitability of any species for revival, taking into account causes of its extinction, possible threats it might face upon resurrection and man’s ability to destroy the species “in the event of unacceptable ecological or socioeconomic impacts.”
  • But the most visceral argument against de-extinction is animal cruelty.
  • “Is it fair to do this to these animals?” Shapiro asked. “Is ‘because we feel guilty’ a good-enough reason?” Stewart Brand made a utilitarian counterargument: “We’re going to go through some suffering, because you try a lot of times, and you get ones that don’t take. On the other hand, if you can bring bucardos back, then how many would get to live that would not have gotten to live?”
  • In “How to Permit Your Mammoth,” published in The Stanford Environmental Law Journal, Norman F. Carlin asks whether revived species should be protected by the Endangered Species Act or regulated as a genetically modified organism.
  • He concludes that revived species, “as products of human ingenuity,” should be eligible for patenting.
  • The term “de-extinction” is misleading. Passenger pigeons will not rise from the grave
  • Our understanding of the passenger pigeon’s behavior derives entirely from historical accounts.
  • There is no authoritative definition of “species.” The most widely accepted definition describes a group of organisms that can procreate with one another and produce fertile offspring, but there are many exceptions.
  • Theseus’ ship, therefore, “became a standing example among the philosophers . . . one side holding that the ship remained the same, and the other contending that it was not the same.”
  • What is coming will go well beyond the resurrection of extinct species. For millenniums, we have customized our environment, our vegetables and our animals, through breeding, fertilization and pollination. Synthetic biology offers far more sophisticated tools. The creation of novel organisms, like new animals, plants and bacteria, will transform human medicine, agriculture, energy production and much else.
haubertbr

Extracts - "Brain" In A Dish Acts As Autopilot Living Computer - 0 views

www.research.ufl.edu/...extract2.html

science

shared by haubertbr on 03 Mar 17 - No Cached
  • haubertbr on 03 Mar 17
     
    The "brain" - a collection of 25,000 living neurons, or nerve cells, taken from a rat's brain and cultured inside a glass dish - gives scientists a unique real-time window into the brain at the cellular level. By watching the brain cells interact, scientists hope to understand what causes neural disorders such as epilepsy and to determine noninvasive ways to intervene.
sissij

Bacteria Have a Social Contract, and Unnamed Natural Laws | Big Think - 1 views

bigthink.com/...-contract-unnamed-natural-laws

science education research social natural

shared by sissij on 30 Mar 17 - No Cached
  • the evolutionary logic of relationships beyond rivalry
  • ~98% of bacterial species don’t thrive outside mixed-species colonies.
  • Bacteria are not self-sufficient: They’ve co-evolved to depend on each other.
  • ...5 more annotations...
  • You’re in a collective extended “survival vehicle” relationship.
  • In a kind of no-brainer biochemical “social contract,” bacterial colonies, like human communities, have to handle the “common good” (suppressing cheating, free-riding, the “tragedy of the commons,” etc).
  • We dominate because we’re the best cooperators (Yuval Harari).
  • Evolution is itself a free-floating logic pattern (for discovering other, ever more effective logic patterns, and enacting “competence without comprehension").
  • Evolution’s logic is like geometry’s: in both relevant patterns and results arise from the intrinsic logic of the elements involved. In geometry, it’s lines, planes, etc. In evolution it’s kinetic functions like survival, varying replication, and adaptation.
  • sissij on 30 Mar 17
     
    I found this article very interesting. Evolution does not happen physically. There is also evolution in the social behavior and relationship in a specie. Even simple organisms like single-celled bacteria have certain behaviors that suggest evolution in "social behavior" even though they don't have brain or intelligence. I feel like it is just like the hydrogen bonds in chemistry that it forms naturally without a doubt. Common good is the ultimate goal of the nature. I think the logic is evolution is very amazing as all the results are because of mindless discovery. --Sissi (3/30/2017)
Maria Delzi

How Life Began: New Clues | TIME.com - 0 views

science.time.com/...egan-new-clues-from-new-worlds

shared by Maria Delzi on 17 Jan 14 - No Cached
  • Astronomers recently announced that there could be an astonishing 20 billion Earthlike planets in the Milky Way
  • How abundant life actually is, however, hinges on one crucial factor: given the right conditions and the right raw materials,
  • what is the mathematical likelihood that life will actually would arise?
  • ...8 more annotations...
  • biology would have to be popping up all over the place.
  • Andrew Ellington, of the Center for Systems and Synthetic Biology at the University of Texas, Austin, “I can’t tell you what the probability is. It’s a chapter of the story that’s pretty much blank.”
  • Given that rather bleak-sounding assessment, it may be surprising to learn that Ellington is actually pretty upbeat. But that’s how he and two colleagues come across in a paper in the latest Science. The crucial step from nonliving stuff to a live cell is still a mystery, they acknowledge, but the number of pathways a mix of inanimate chemicals could have taken to reach the threshold of the living turns out to be many and varied. “It’s difficult to say exactly how things did occur,” says Ellington. “But there are many ways it could have occurred.
  • The first stab at answering the question came all the way back in the 1950s, when chemists Stanley Miller and Harold Urey passed an electrical spark through a beaker containing methane, ammonia, water vapor and hydrogen, thought at the time to represent Earth’s primordial atmosphere.
  • Scientists have learned so much, in fact, that the number of places life might have begun has grown to include such disparate locations as the hydrothermal vents at the bottom of the ocean; beds of clay; the billowing clouds of gas emerging from volcanoes; and the spaces in between ice crystals.
  • The number of ideas about how the key step from organic chemicals to living organisms might have been taken has multiplied as well: there’s the “RNA world hypothesis” and the “lipid world hypothesis” and the “iron-sulfur world hypothesis” and more, all of them dependent on a particular set of chemical circumstances and a particular set of dynamics and all highly speculative.
  • “Maybe when they do,” says Ellington, “we’ll all do a face-plant because it turns out to be so obvious in retrospect.” But even if they succeed, it will only prove that a manufactured cell could represent the earliest life forms, not that it actually does. “It will be a story about what we think might have happened, but it will still be a story.”
  • The story Ellington and his colleagues have been able to tell already, however, is a reason for optimism. We still don’t know the odds that life will arise under the right conditions. But the underlying biochemistry is abundantly, ubiquitously available—and it would take an awfully perverse universe to take things so far only to shut them down at the last moment.
Sophia C

Gene therapy scores big wins against blood cancers - Yahoo News - 0 views

news.yahoo.com/t-blood-cancers-160100028.html

gene research science knowledge

shared by Sophia C on 08 Dec 13 - No Cached
  • "You can take a cell that belongs to a patient and engineer it to be an attack cell."
grayton downing

BBC News - First human trial of new bone-marrow transplant method - 0 views

www.bbc.co.uk/...health-24609025

human trial transplant science

shared by grayton downing on 22 Oct 13 - No Cached
  • Doctors at London's Great Ormond Street Hospital have carried out a pioneering bone-marrow transplant technique.
  • Mohammed Ahmed, who is nearly five years old, was among the first three children in the world to try out the new treatment.
  • Mohammed's doctors then modified these donated immune cells, called "T-cells", in the lab to engineer a safety switch - a self-destruct message that could be activated if Mohammed's body should start to reject them once transplanted.
  • ...2 more annotations...
  • "We waited for a full match but it did not come. By the grace of God, we took the decision to have the treatment.
  • There are currently about 1,600 people in the UK waiting for a bone-marrow transplant and 37,000 worldwide.
summertyler

Forget what you think you know about how memory works | Genetic Literacy Project - 0 views

www.geneticliteracyproject.org/...ou-know-about-how-memory-works

memory research psychology

shared by summertyler on 02 Jun 15 - No Cached
  • Where do memories come from?
  • For quite some time the science of memories seemed focused on one pathway, but now there is new research indicating that this is only part of a larger story
  • There’s a kind of fashion about memory – like many mental models constructed for difficult concepts, the signs of the times inform how the current models approach the inquiry.
  • ...8 more annotations...
  • movement in the nervous system created memories
  • memories are the encoding of experiences on webs of neurons in the brain
  • memory involved molecular changes via neurotransmitters in the brain
  • the neuron cell bodies themselves have some connection to the memory and control over the development and sustainment of synapses.
  • “Long-term memory is not stored at the synapse,”
  • part of memory is stored within the cells (neurons) themselves, and that they are using this memory storage to determine how many synapses to form and where.
  • Long-term memory is a function of the growth of new synaptic connections caused by the serotonin
  • As long-term memories are formed, the brain creates new proteins that are involved in making new synapses. If that process is disrupted — for example by a concussion or other injury — the proteins may not be synthesized and long-term memories cannot form. This is why people cannot remember what happened moments before a concussion.
  • summertyler on 02 Jun 15
     
    How memory works.
julia rhodes

Do Our Bones Influence Our Minds? : The New Yorker - 0 views

www.newyorker.com/...bones-influence-our-minds.html

psychology brain science technology science research knowledge bones influence minds

shared by julia rhodes on 05 Nov 13 - No Cached
  • But their skeletons appeared essentially normal, he says, a result that left him “deeply depressed.”
  • It turns out that osteocalcin is a messenger, sent by bone to regulate crucial processes all over the body.
  • The finding represents new ground in how researchers view the skeleton: not only do bones provide structural support and serve as a repository for calcium and phosphate, they issue commands to far-flung cells
  • ...8 more annotations...
  • “This is a biggie,” said Eric Kandel, the neuroscientist and Nobel Laureate. “Who thinks of the bone as being an endocrine organ? You think of the adrenal gland, you think of the pituitary, you don’t think of bone.”
  • he most recent finding concerns the skeleton and the brain.
  • Karsenty showed that bone plays a direct role in memory and mood. Mice whose skeletons did not produce osteocalcin as a result of genetic manipulation were anxious, depressed, and almost completely unable to master a test of spatial memory. When Karsenty infused them with the missing hormone, however, their moods improved and their performance on the memory test became nearly normal. He also found that, in pregnant mice, osteocalcin from the mother’s bones crossed the placenta and helped shape the development of the fetus’s brain. In other words, bones talk to neurons even before birth.
  • As we age, our bone mass decreases. Memory loss, anxiety, and depression also become more common. These may be separate, unfortunate facts about getting old, but they could also be related.
  • Even more fantastically: Would it ever be possible to protect memory or treat age-related cognitive decline with a skeletal hormone? These are the kinds of questions that can spur either false hopes or imaginative leaps.
  • “I don’t know of any hormone that functions in mice but not to some extent in humans,” Thomas Clemens, of Johns Hopkins, told me in 2011
  • ne tantalizing hint comes from men who are unable to respond to the hormone as a result of a genetic mutation
  • Karsenty also believes that we know enough now to recognize that the body is far more networked and interconnected than most people think. “No organ is an island,” he likes to say.
pantanoma

Introduction: The Human Brain - life - 04 September 2006 - New Scientist - 0 views

www.newscientist.com/...nt-expert-the-human-brain.html

human brain science

shared by pantanoma on 31 May 15 - No Cached
  • The brain is the most complex organ in the human body
  • It is in these changing connections that memories are stored, habits learned and personalities shaped, by reinforcing certain patterns of brain activity, and losing others.
  • While people often speak of their "grey matter", the brain also contains white matter. The grey matter is the cell bodies of the neurons, while the white matter is the branching network of thread-like tendrils - called dendrites and axons - that spread out from the cell bodies to connect to other neurons.
  • ...2 more annotations...
  • The brain has bursts of growth and then periods of consolidation, when excess connections are pruned. The most notable bursts are in the first two or three years of life, during puberty, and also a final burst in young adulthood.
  • t is the most evolutionarily recent brain structure, dealing with more complex cognitive brain activities.
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