Mind Matters Natural and Artificial Intelligence News and Analysis

CategoryNeuroscience

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3D human brain

Even Neurons Have Rich Clubs and Poor Clubs

Both — doing different jobs — are essential to the brain’s functioning

New York University School of Medicine neuroscientist György Buzsáki offers a long essay at Scientific American, explaining how he came to adopt an “inside-out,” rather than an “outside-in” perspective on how the brain works. The brain, in his view, is primarily preoccupied with self-organization and it incorporates outside information in order to help with that project. Along the way, he entertainingly describes two different types of neurons and what they do: Most neurons are only weakly connected to others, whereas a smaller subset retains robust links. The strongly connected minority is always on the alert. It fires rapidly, shares information readily within its own group, and stubbornly resists any modifications to the neurons’ circuitry. Because of the multitude of connections…

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A trio of woolly mammoths trudges over snow covered hills.  Behind them, mountains with snow covered peaks rise above dark green forests of fir trees. 3D Rendering

Did Small Brains Doom the Mammoth and the Giant Armadillo?

A recent study showed that survivors had brains that were 53% larger, which was perhaps useful in avoiding predators

A recent study of mammal extinctions during and after the Ice Age found that the large mammals (megafauna) that went extinct during the period of 115,000 years ago through 500 years ago (the Late Quaternary) had smaller brains in relation to body mass than those that survived: The researchers explain that the last Ice Age was characterized by the widespread extinction of large and giant animals on all continents on earth (except Antarctica). Among these were, in America, giant ground sloths weighing 4 tons, a giant armadillo weighing a ton, and mastodons; in Australia the marsupial diprotodon weighing a ton, giant kangaroos, and a marsupial ‘lion’; and in Eurasia giant deer, woolly rhinoceros, mammoth, and giant elephants weighing up to…

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nerve cells

New Learning Model for Brain Overturns 70 Years of Theory

The new model, if confirmed, could change the way algorithms are developed

According to new research, when learning takes place, it’s not just the synapses (by which neurons send signals to each other but the whole communication structure (the dendrites) of the neuron that changes. The researchers compare the synapses to leaves and the dendrites to a tree. This, if it replicates, is a radical revision from nearly a century ago. For the last 70 years a core hypothesis of neuroscience has been that brain learning occurs by modifying the strength of the synapses, following the relative firing activity of their connecting neurons. This hypothesis has been the basis for machine and deep learning algorithms which increasingly affect almost all aspects of our lives. But after seven decades, this long-lasting hypothesis has…

Independent Thinking

A British Philosopher Looks For a Way to Redefine Free Will

Julian Baggini’s proposed new approach assumes the existence of the very qualities that only a traditional view of the mind offers

British philosopher Julian Baggini, author of The Great Guide: What David Hume Can Teach Us about Being Human and Living Well (2021) argues against the idea of free will, as commonly understood (voluntarist free will). Citing the fact that the world is controlled by physics, he writes, No matter how free we feel, our understanding of nature tells us that no choice originates in us but traces its history throughout our histories and our environments. Even leaving aside physics, it seems obvious that, at the moment of any choice, the conditions for that choice have already been set, and to be able to escape them would be no more than the ability to generate random actions. And if all that…

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3D illustration of Interconnected neurons with electrical pulses.

The Mysterious White Matter of the Brain

It’s difficult to study but turns out to be very important

We all talk about “gray matter,” the cerebral cortex of the brain, thought to be the basis for learning, remembering, and reasoning. But what about “white matter”? Neurologist Christopher Filley has the story as to why we don’t know much about it: This lack of recognition largely stems from the difficulty in studying white matter. Because it’s located below the surface of the brain, even the most high-tech imaging can’t easily resolve its details. But recent findings, made possible by advancements in brain imaging and autopsy examinations, are beginning to show researchers how critical white matter is. White matter is comprised of many billions of axons, which are like long cables that carry electrical signals. Think of them as elongated…

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Close up of Grooved brain coral labyrinth

An Ocean in Our Brains?

An “ocean” does not hardly begin to describe our brains.,

An “ocean” does not hardly begin to describe our brains: For years, the brain has been thought of as a biological computer that processes information through traditional circuits, whereby data zips straight from one cell to another. While that model is still accurate, a new study shows that there’s also a second, very different way that the brain parses information: through the interactions of waves of neural activity. The findings help researchers better understand how the brain processes information. Salk Institute, “An ocean in your brain: Interacting brain waves key to how we process information ” at Salk Institute (April 22, 2022) It is probably much more complex even than that. The paper is open access. You may also wish…

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In Control Room Doctor and Radiologist Discuss Diagnosis while Watching Procedure and Monitors Showing Brain Scans Results, In the Background Patient Undergoes MRI or CT Scan Procedure.

Can a Human Being Be Gifted Despite Missing Lots of Brain?

So many would think — but that’s not what the evidence shows

A most interesting recent article by Grace Browne at Wired discusses the fact that a woman who prefers to be known only as EG — but is in her fifties — has lived a quite interesting life while missing a large portion of her brain: For EG, who is in her fifties and grew up in Connecticut, missing a large chunk of her brain has had surprisingly little effect on her life. She has a graduate degree, has enjoyed an impressive career, and speaks Russian—a second language––so well that she has dreamed in it. She first learned her brain was atypical in the autumn of 1987, at George Washington University Hospital, when she had it scanned for an unrelated reason.…

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Dolbadarn Castle

Yes! There Is Evidence For the Intelligent Design of the Brain

If our brains were not intelligently designed, we would have no reason to believe anything our senses tell us

This is a big topic, of course. The brain, like all of biology, is obviously intelligently designed. From the elegant coordination of neural activity between neurons and brain regions to the remarkable law-like behavior of individual molecules and atoms that comprise neurons and neurotransmitters, the brain carries the unmistakable fingerprint of a Designer. But there is another common-sense way to infer design of the brain that is simple and I think quite convincing — it is based on our belief that our perceptions and concepts accord with truth. To see how this points to intelligent design of the brain, consider a very compelling argument for God’s existence proposed by philosopher Richard Taylor (1919–2003) in his book Metaphysics. Thomist philosopher Edward…

A man going through the dark old tunnel. Tunnel with traffic lights and a silhouette of a man

Remember When Near-Death Experiencers Were Mental Cases?

Scientists “knew” it wasn’t true. Then modern medicine started bringing people back from the dead…

Here’s ScienceDaily’s writeup of the near-death experiences paper published at the New York Academy of Sciences. It didn’t used to be the case that near-death experiences got written up anywhere except in a psychiatrist’s notebook. Something is changing: “Cardiac arrest is not a heart attack, but represents the final stage of a disease or event that causes a person to die,” lead author Parnia explains. “The advent of cardiopulmonary resuscitation (CPR) showed us that death is not an absolute state, rather, it’s a process that could potentially be reversed in some people even after it has started. “What has enabled the scientific study of death,” he continues, “is that brain cells do not become irreversibly damaged within minutes of oxygen…

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tunnel of light

Neuroscientists: Near-death perceptions not just hallucinations

Published in the Annals of the New York Academy of Sciences

One of the authors, Sam Parnia is a well-known researcher in this area: Due to advances in resuscitation and critical care, many people are surviving near-death experiences. Survivors’ recalled experiences are not consistent with hallucinations, but instead, follow a specific narrative arc involving perception. Scientific advances in the 20th and 21st centuries have led to a major evolution in the understanding of death. At the same time, for decades, people who have survived an encounter with death have recalled unexplained lucid episodes involving heightened consciousness and awareness. These have been reported using the popular—yet scientifically ill-defined—term “near-death experiences”. A multidisciplinary team of national and international leaders, led by Sam Parnia, MD, Ph.D., director of Critical Care and Resuscitation Research at…

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neuron cell with electrical pulses concept 3d illustration.

Our Neurons’ Electrical Synapses Are the Dark Matter of the Brain

These aren’t the familiar chemical synapses but a second set, the electrical synapses that enable currents to travel directly between neurons from pore to pore.

The universe has its dark matter, the 23% of matter that we know is out there but can’t see because it emits no light. The brain has its own “dark matter” too, in the form of electrical synapses. These are not the chemical synapses by which neurons transmit a stimulus from one cell to the next. They are a second layer of synapse that allows message-carrying currents to flow passively from one neuron to another through pores in the neurons’ cell walls. They are likely important because just about every type of animal except echinoderms (starfish and sand dollars, for example) has them — and yet we don’t know much about them: ”Electrical synapses are much rarer and are hard…

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Super macro shot tiny fruit flies on the top of a banana

The Brain Unfolds Like a Drama, With Neurons in Different Roles

Researchers studying fruit flies hope that spotting the stages at which human neurons go missing or wrong can help develop treatments to insert or replace them

We are not accustomed to thinking of fruit flies as even having brains. But they have 120 types of neurons in their visual system alone (which could be why they are so pesky): In the research published in Nature, the researchers studied the brains of the fruit fly Drosophila to uncover the complete set of tTFs needed to generate the roughly 120 neuron types of the medulla, a specific brain structure in the visual system of flies. They used state-of-the-art single-cell mRNA sequencing to obtain the transcriptome — all of the genes expressed in a given cell — of more than 50,000 individual cells that were then grouped into most of the cell types present in the developing medulla… The…

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Brain surgery

What Would Head or Partial Brain Transplants Do To Consciousness?

Researchers had some success swapping rodent heads (though there’s a catch) but no luck with monkeys. And then animal lovers weighed in…

Science writer Max G. Levy, profiling Brandy Schillace’s book, Mr. Humble and Dr. Butcher (2021), reminds us of the strange case of neurosurgeon Dr. Robert White (1926–2010) and his quest to develop human head transplants — or, as he liked to put it, body transplants. A new body for your old head… an offbeat form of immortality. White started with rhesus monkeys. At Case Western Reserve University, starting in 1970, he attempted many such transplants. Only one attempt succeeded (sort of). Without the usual spinal connections and thus without access to a body, the monkey head lived only nine days. Another such monkey head transplant was reported in 2016 — carried out by Xiaoping Ren at Harbin Medical University, China…

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dramatic lit image of a bloody crime scene with a knife on the floor

Firefly Episode 9: A Medical Heist — the Best So Far

Simon, with access to medical equipment, diagnoses his erratic sister’s neurological issues — after she has unaccountably stabbed Jayne

This is my favorite episode so far. It’s a classic heist with all the traditional beats! The crew is sitting around the table talking and eating while Jayne cleans his gun. He keeps spitting on the various parts for some reason, and Simon asks him to stop. He doesn’t. Jayne keeps spitting on the parts, glaring at Simon all the while River, Simon’s sister, gets up, grabs a butcher knife, and slashes Jayne across the chest. Jayne hits her, but she looks up, stares at the big man, and says, “He looks better in red.” With the stakes suddenly raised, the mystery of what happened to River surges to the forefront again. It’s time to get some answers. It so…

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Orchestra rehearsal

Memory Leans More on the Brain’s Electric Field Than on Neurons

MIT researchers compare the electric field to an orchestra conducting the neurons as players

The Picower Institute for Learning and Memory at MIT offers an interesting new model of how memories are processed in the brain. Using two macaques playing a game while their brain activities were recorded, the researchers suggest the orchestra as a model. The neurons are the players and the electric field is the conductor: As the brain strives to hold information in mind, such as the list of groceries we need to buy on the way home, a new study suggests that the most consistent and reliable representation of that information is not the electrical activity of the individual neurons involved but an overall electric field they collectively produce. Indeed, whenever neuroscientists have looked at how brains represent information in…

Depth electrode on brain MRI imaging.

Imaging Studies Fail Badly at Linking Brain and Behavior

Aha! news stories about what brain imaging reveals about human behavior are probably based on studies whose findings would not be confirmed by further research.

Brain imaging has shed much light on medical conditions in recent decades. So it was hardly good news for neuroscientist Scott Marek at the University of Washington when the results of a study linking brain function with intelligence in 2000 children produced very counterintuitive results. He and his colleagues had divided the sample into two groups of 1000 and run the same analysis on each — and they did not match. At first, he told Nature, “I stared out of my apartment window in depression, taking in what it meant for the field.” Then the team decided to study the problem on a larger scale, using the three key studies in this type of research, the Adolescent Brain Cognitive Development…

Brain under water 3D render, subconscious mental life and brainstorm idea.

Consciousness Experiments Confirm Each Research Group’s Theories

Human consciousness is by far the biggest mystery in the universe. We can be pretty sure that a researcher bold enough to claim to have found simple answer is mistaken. A recent study out of Tel Aviv University dramatically illustrates the problems we face. The researchers, focusing on the methods of study (methodological choices) that consciousness researchers from various schools of thought chose, found that a computer program could predict their results with 80% accuracy. That wasn’t supposed to happen: “The big question is how consciousness is born out of activity in the brain, or what distinguishes between conscious processing and unconscious processing,” Prof Mudrik explains. “For example, if I see a red rose, my visual system processes the information…

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Concept of modern technical equipment to scanning damaged brain

Confirmed: “Secret” Tunnels Connect Our Skulls and Brains

The newly confirmed skull tunnels produce immune system cells and funnel them to the brain in case of inflammation or damage

Neuroscientists usesd to think that immune system cells were carried in the bloodstream from, say, big leg bones in order to address brain inflammation following a stroke, injury, or disorder. It turns out that the brain gets neutrophils from much closer to home, right under the scalp. That’s what one group discovered when looking for the cells in the tibia (the larger of the shinbones in the leg) in mice: They found that the skull contributed significantly more neutrophils to the brain in the event of stroke and meningitis than the tibia. But that raised a new question – how were the neutrophils being delivered? “We started examining the skull very carefully, looking at it from all angles, trying to…

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Frog hiding in the mud

Science Writer: Explain-Away-the-Mind Book Doesn’t Succeed

In a departure from an all-too familiar approach to science writing, Philip Ball offers constructive criticism of the “nothing but”approach to the mind

At eminent science journal Nature, science writer Philip Ball reviews a book offering to explain how the mind arose from the mud. And he departs from the script. The book is Journey of the Mind: How Thinking Emerged from Chaos by neuroscientists Ogi Ogas and Sai Gaddam. One would expect a conventional science writer to announce that this new book is an important contribution to the quest to naturalize the human mind — to show that the mind is a mere adaptation that enabled the tailless ape to survive the savannah. Such a belief needn’t be true (and isn’t); it’s intended as a placeholder for a better-founded purely naturalist belief. Yet Ball looks at the claims made in Journey of…

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Texture of multi-colored sweet marshmallows. Marshmallows candy for background.

Can Waiting for a Marshmallow Predict a Child’s Future?

Believing so was all the rage in recent decades but later research didn’t back up the idea

You’ve maybe heard of Stanford University’s “marshmallow experiment,” right? A child’s future can be predicted, we were told by psychologist Walter Mischel (1930–2018), by whether the child can delay gratification: Walter Mischel’s pioneering research at Bing in the late 1960s and early 1970s famously explored what enabled preschool-aged children to forgo immediate gratification in exchange for a larger but delayed reward… This research identified some of the key cognitive skills, strategies, plans and mindsets that enable self-control. If the children focused on the “hot” qualities of the temptations (e.g., “The marshmallows are sweet, chewy, yummy”), they soon rang the bell to bring the researcher back. If they focused on their abstract “cool” features (“The marshmallows are puffy and round like…