One problem with materialist models of the mind — machine-like or not — is that they don’t account for people who have selves despite serious brain gaps.
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We are used to thinking of data compression in connection with computers but a recent study with mice shows that brains compress data too. The researchers ask us to imagine a dilemma from anearly video game: If you were a kid in the 80s, or are a fan of retro video games, then you must know Frogger. The game can be quite a challenge. To win, you must first survive a stream of heavy traffic, only to then narrowly escape oblivion by zig-zagging across speeding wooden logs. How does the brain know what to focus on within all this mess? Champalimaud Centre for the Unknown, “The brain applies data compression for decision-making” at Eurekalert (June 6, 2022) Driving in snarled, Read More ›
Neuroscientist Andrew Newberg, co-author with Daniel A. Monti, M.D., of Brain Weaver: Creating the Fabric for a Healthy Mind through Integrative Medicine (Kales Press, 2021), reflected recently on what studies on the mental health benefits of spirituality can teach us. Some of the benefits of spirituality are due to the lifestyle changes it promotes: For example, going to church or other social events that are part of a religious tradition can be beneficial because social support, in and of itself, is beneficial to our mental health. The more people that we have in our social support network, the better we are at coping with various life stressors including problems with jobs, relationships, or health. Most religions also teach people to Read More ›
Abigail Howell, a biomedical student at ArizonaState University, explains that there are three different types of optical illusion, in which the brain incorrectly interprets what the eyes are seeing: Literal optical illusions are often produced by putting together a collection of multiple images. Each individual image may be easy to see, but the images together may look very different than the originals. This is accomplished through what is known as the “filling-in phenomena.” When the eye sends visual information to the brain, the brain chooses what parts to focus on. Depending on the focus, different layers of the image may be seen. Abigail Howell, “Ask a biologist: What causes optical illusions?” at ArizonaState University She offers as an example of Read More ›
Death is an event that is more like a process. Some brain cells even become more active after we die. Neuroscientist Jeffrey A. Loeb explains: “Most studies assume that everything in the brain stops when the heart stops beating, but this is not so,” says the study’s corresponding author Jeffrey Loeb, the John S. Garvin Professor and head of neurology and rehabilitation at the UIC’s College of Medicine. Robby Berman, “‘Zombie’ genes in the brain get to work after you die” at Big Think (March 26, 2021) He and colleagues discovered gene expression in tissue from brain surgery that did not jive with the expressions observed in living humans, whether or not those humans had any neurological disorders. Because he Read More ›
In the ongoing research puzzle as to exactly why humans are significantly smarter than other animals, researchers writing in Nature Neuroscience have adopted an information theory approach, describing the human brain as a “distributed information-processing system.” They found that we process information differently from other primates. Our brain regions for sensory and motor functions use a simple input/output system with high reliability due to high redundancy (repetition). Our eyes duplicate most of each other’s information but that helps ensure that our view of the scene is correct. However, there is a very different way of processing information — synergistic processing — which integrates signals from across a variety of brain networks. This approach is better adapted, the researchers say, to Read More ›
At Scientific American, we learn from a team of neuroscientists, how our brains distinguish important from unimportant sensations. We filter out many more signals than we pay attention to, especially in familiar situations. We notice what has changed — especially if it’s an opportunity or a problem. While the prefrontal cortex is associated with decision-making, it turns out to get some help from a tiny structure in the brain stem, as these researchers discovered: How does the brain accomplish these feats of focus? In recent research at Northwestern University, the University of Chicago and the Salk Institute for Biological Studies in La Jolla, Calif., we have illuminated a new answer to this question. Through several studies, we have discovered that Read More ›
Although we have been told since 1968 that brain death is irreversible (“A definition of irreversible coma. Report of the Ad Hoc Committee of the Harvard Medical School to Examine the Definition of Brain Death”), some are beginning wonder whether, with newer technologies, that is still true. Bioquark CEO Ira S. Pastor offers some thoughts: Despite the label of irreversibility associated with the 1968 Harvard Ad Hoc Committee definition, there are several documented cases in the literature of potential brain death reversal, primarily associated with younger subjects whose central nervous system maintained some degree of underlying neuroplasticity. As most leaders in this field acknowledge that residual “nests” of neuronal activity and residual blood flow do indeed exist in the recently Read More ›
While the human brain appears essential to being human, people can live normally — and even excel — with large parts of the brain missing or with brains that have been cut in half. That happened to EG, who grew up missing her left temporal lobe. As told at Wired: 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 Read More ›
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 Read More ›
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 Read More ›
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 Read More ›
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 Read More ›
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 Read More ›
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 Read More ›
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. Read More ›
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 Read More ›
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 Read More ›
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 Read More ›
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 Read More ›