Time on the Brain: How You Are Always Living In the Past, and Other Quirks of Perception. I always knew we humans have a rather tenuous grip on the concept of time, but I never realized quite how tenuous it was until a couple of weeks ago, when I attended a conference on the nature of time organized by the Foundational Questions Institute. This meeting, even more than FQXi’s previous efforts, was a mashup of different disciplines: fundamental physics, philosophy, neuroscience, complexity theory. Crossing academic disciplines may be overrated, as physicist-blogger Sabine Hossenfelder has pointed out, but it sure is fun. Like Sabine, I spend my days thinking about planets, dark matter, black holes—they have become mundane to me.
But brains—now there’s something exotic. So I sat rapt during the neuroscientists’ talks as they described how our minds perceive the past, present, and future. “Perceive” maybe isn’t strong enough a word: our minds construct the past, present, and future, and sometimes get it badly wrong. Whenever I hear about such tests, I brace myself for bad news. Flash-Lag Effect - D. M. Eagleman. This is a page of supplemental information for D. M. Eagleman and T. J. Sejnowski, Motion Integration and Postdiction in Visual Awareness, Science, 287(5460), 2000, and for follow-up Technical Comments. Eagleman, D.M. & Sejnowski, T.J. (2000) Motion integration and postdiction in visual awareness.
Science. 287(5460): 2036-8. [Full text (pdf)]Eagleman, D.M. & Sejnowski, T.J. (2000) The position of moving objects: Response. The goal of this line of research is to close in on a connection between physical mechanisms present in neural tissue and the perceptual functions that these mechanisms embody. "Life must be lived forward, but can only be understood backward" - Soren Kierkegaard, The Journals of Kierkegaard (Please note: this page is not currently maintained, and has not been updated since 2007) The flash-lag effect is a visual illusion wherein a flash and a moving object that appear in the same location are perceived to be displaced from one another (MacKay, 1958; Nijhawan, 1994).
The Cyborg in Us All. How Embarrassing: Researchers Pinpoint Self-Consciousness in the Brain. Feeling embarrassed? You can probably thank your pregenual anterior cingulate cortex (pACC), a boomerang-shaped region of the brain nestled behind the eyes. Cognitive scientists at the University of California, San Francisco, and U.C. Berkeley probed the neuroanatomy of embarrassment by asking healthy people and those with neurodegenerative diseases to sing along to the Temptations’ “My Girl.” Horns blared, strings flowed and the subject’s voice soared—and then the music and professional vocals were stripped away. The subjects had to watch a video of their own solitary singing while researchers measured their racing hearts, sweaty palms, squirms and grimaces. Those with damage in the right pACC were least likely to cringe at their own performance.
The study, presented in April at the American Academy of Neurology conference in Hawaii, adds further evidence that this brain region has a role in many emotions, says U.C.S.F. postdoctoral fellow Virginia Sturm. Neuroscience Challenges Old Ideas about Free Will. Do we have free will? It is an age-old question which has attracted the attention of philosophers, theologians, lawyers and political theorists. Now it is attracting the attention of neuroscience, explains Michael S. Gazzaniga, director of the SAGE Center for the Study of the Mind at the University of California, Santa Barbara, and author of the new book, “Who’s In Charge: Free Will and the Science of the Brain.”
He spoke with Mind Matters editor Gareth Cook. Cook: Why did you decide to tackle the question of free will? Gazzaniga: I think the issue is on every thinking person’s mind. I can remember wondering about it 50 years ago when I was a student at Dartmouth. Now, after 50 years of studying the brain, listening to philosophers, and most recently being slowly educated about the law, the issue is back on my front burner. Cook: What makes you think that neuroscience can shed any light on what has long been a philosophical question?
Having said that, philosophers can’t have all the fun. The Evolution of Grief, Both Biological and Cultural, in the 21st Century | Culturing Science. Three months ago, I received an email informing me that a high school friend, Pat, had died. I read his obituary and my body stopped functioning. I froze on the spot, limbs tense but trembling. My mouth went dry, my vision blurred. As I waited for my train in the packed station, I could barely stand as my muscles turned to jelly and legs folded beneath my body. I tried to maintain composure in the public space, but my contorted face betrayed my sorrow. It was shocking to me: I felt real physical pain — a biological response brought about by stress hormones — in response to death. Evolutionary biologists think that grief is passed on not because it provides benefit in itself, but rather it is a side effect of having relationships.
In more social animals, such as humans, those reciprocal relationships extend beyond parent-child. This idea was endlessly comforting in my mourning. Grief is the price we pay for friendship. Digital love The onslaught of mourning continued, nonetheless. Images: Why Walking through a Doorway Makes You Forget. The French poet Paul Valéry once said, “The purpose of psychology is to give us a completely different idea of the things we know best.” In that spirit, consider a situation many of us will find we know too well: You're sitting at your desk in your office at home. Digging for something under a stack of papers, you find a dirty coffee mug that’s been there so long it’s eligible for carbon dating. Better wash it. You pick up the mug, walk out the door of your office, and head toward the kitchen.
By the time you get to the kitchen, though, you've forgotten why you stood up in the first place, and you wander back to your office, feeling a little confused—until you look down and see the cup. So there's the thing we know best: The common and annoying experience of arriving somewhere only to realize you've forgotten what you went there to do. Sometimes, to get to the next object the participant simply walked across the room. This “doorway effect” appears to be quite general. Charles B. Cache Cab: Taxi Drivers' Brains Grow to Navigate London's Streets. Manhattan's midtown streets are arranged in a user-friendly grid. In Paris 20 administrative districts, or arrondissements, form a clockwise spiral around the Seine. But London? A map of its streets looks more like a tangle of yarn that a preschooler glued to construction paper than a metropolis designed with architectural foresight. Yet London's taxi drivers navigate the smoggy snarl with ease, instantaneously calculating the swiftest route between any two points.
These navigational demands stimulate brain development, concludes a study five years in the making. With the new research, scientists can definitively say that London taxi drivers not only have larger-than-average memory centers in their brains, but also that their intensive training is responsible for the growth. Neuroscientist Eleanor Maguire of University College London (U.C.L.) first got the idea to study London cab drivers from research on memory champions of the animal world. MIND Reviews: Harnessed: How Language and Music Mimicked Nature and Transformed Ape to Man. The Neuroscience of Barbie. In science fiction and fantasy tales, there is a long running fascination with the idea of dramatically diminishing or growing in stature. In the 1989 classic, Honey, I Shrunk the Kids, Rick Moranis invents a device which accidentally shrinks both his own and the neighbor’s children down to a quarter-of-an-inch tall.
Preceding this by more than 100 years, Lewis Carroll wrote about a little girl who, after tumbling down a rabbit hole, nibbles on some cake and then grows to massive proportions. Nearly 300 years ago, Jonathan Swift described the adventures of Gulliver while on the island of Lilliputan, on which he is a giant, and then on the island of Brobdingnag, where everyone else is a giant. These kinds of experiences, however, have been limited to the world of fictional stories. The world around us does not actually change in size. Nor, with the exception of too many late-night Chinese deliveries, do our bodies become appreciably larger or smaller. Crab's Brain Encodes Complex Memories. The Chasmagnathus granulatus crab leads a simple life. It spends its days burrowing for food and trying to avoid its nemesis, the seagull. But recent research has shown that despite its rudimentary brain, this crab has a highly sophisticated memory. For example, it can remember the location of a seagull attack and learn to avoid that area.
In mammals, this kind of behavior requires multiple brain regions, but a study published in the June issue of the Journal of Neuroscience suggests that the C. granulatus crab can manage with just a few neurons. Neuroscientists at the University of Buenos Aires used cardboard cutouts of seagulls to test crabs’ memory skills. The researchers tied the crabs’ behavior to lobula giant neurons, a type of brain cell found in crustaceans. The American Fascination With Zombies | Anthropology in Practice. Ed note: As Halloween rapidly approaches in the US, AiP will be exploring superstitions, beliefs, and the things that go bump in the night.
This post originally appeared on AiP on May 17th, 2011, in response to Zombie Awareness Month—oh, it’s real all right. It’s been slightly modified for this posting. I think I must be prepared. For what? The impending zombie apocalypse, of course! Surely the plethora of zombie movies, books, survival guides, and even exercise regimens have given me a sense of how to survive in the event of this particular catastrophe. Zombies aren’t pretty creatures. Folklore is home to a host of undead characters: mummies, skeletons, vampires, ghouls, and ghosts can be found under one name or another in almost all mythologies. This corporeal zombie—distinguished from the spiritual zombie that Vodoun beliefs also permit—is the basis for the Hollywood zombie, which cannot be controlled and is bent on destruction. Zombies are not meant to be. Referenced: Neurons Offer Clues to Suicide. A certain type of brain cell may be linked with suicide, according to a recent investigation.
People who take their own lives have more densely packed von Economo neurons, large spindle-shaped cells that have dramatically increased in density over the course of human evolution. Researchers in Germany analyzed the roots of suicide in the brain by focusing on a neural network linked with psychological pain, which includes regions such as the anterior cingulate cortex and the anterior insula, where von Economo neurons are concentrated. These cells bear receptors for neurotransmitters that help to regulate emotion, such as dopamine, serotonin and vasopressin. Because they are found in highly gregarious animals such as whales, elephants and apes—with humans possessing the highest densities—scientists believe they might specifically deal with complex social emotions such as shame. Brain Likely Encodes the World in 2 Dimensions.
When we drive somewhere new, we navigate by referring to a two-dimensional map that accounts for distances only on a horizontal plane. According to research published online in August in Nature Neuroscience, the mammalian brain seems to do the same, collapsing the world into a flat plane even as the animal skitters up trees and slips deep into burrows. “Our subjective sense that our map is three-dimensional is illusory,” says Kathryn Jeffery, a behavioral neuroscientist at University College London who led the research.
Jeffery studies a collection of neurons in and around the rat hippocampus that build an internal representation of space. As the animal travels, these neurons, called grid cells and place cells, respond uniquely to distance, turning on and off in a way that measures how far the animal has moved in a particular direction. Past research has focused on how these cartographic cells encode two-dimensional space. The Neuroscience of Beauty. The notion of “the aesthetic” is a concept from the philosophy of art of the 18th century according to which the perception of beauty occurs by means of a special process distinct from the appraisal of ordinary objects. Hence, our appreciation of a sublime painting is presumed to be cognitively distinct from our appreciation of, say, an apple.
The field of “neuroaesthetics” has adopted this distinction between art and non-art objects by seeking to identify brain areas that specifically mediate the aesthetic appreciation of artworks. However, studies from neuroscience and evolutionary biology challenge this separation of art from non-art. Human neuroimaging studies have convincingly shown that the brain areas involved in aesthetic responses to artworks overlap with those that mediate the appraisal of objects of evolutionary importance, such as the desirability of foods or the attractiveness of potential mates. How does the anterior insula fit into this story? Brains Built to Cooperate: Scientific American Podcast.
We are social animals. So you might assume our brains are built to excel when we cooperate with each other, as opposed to when we function in isolation. Now research with another animal supports that notion. Plain-tailed wrens in Ecuador are famous for duets between males and females. While their song is done cooperatively, with the male and female singing alternate syllables, it sounds surprisingly like one bird singing solo. Scientists who have recorded and analyzed hundreds of such songs decided to capture some of the birds to monitor the brain regions responsible for singing. They anticipated that the birds’ neurons would respond strongest to their own individual voice.
But that’s not what happened. They found that the birds’ neurons reacted far more strongly to the duet than when they sang their parts alone. That’s fine for Ecuadorian birds but what about us humans? —Christie Nicholson [The above text is a transcript of this podcast.] Neural Networking: Your Brain's Internal Connections Operate Like a Country Club: Scientific American Gallery. Conciousness and healthy brain function appear to emerge not from neurons, but from the networks linking them together. Scientists are only just beginning to map that complex network and understand how it works.
Whereas previous studies have shown that some regions of the human brain have more connections than others, until now no one has known exactly how those "hubs" interact. A new study, published November 2 in The Journal of Neuroscience, used MRI scans to map brain activity in 21 people. They found that the areas with the most connections—the hubs—were more strongly connected to one another than to other, less popular regions. The researchers liken the favored networks to a country club setting, in which people with a great number of social connections bond with other connection-rich socialites.
The close-knit organization of these central hubs helps the brain stay resilient to damage. —Sarah Fecht. Memory in the Brain [Interactive] Female orgasm captured in series of brain scans | Science. Bedside detection of awareness in the vegetative state: a cohort study. Guiding lights. Brain Exam Detects Awareness in 3 ‘Vegetative’ Patients. The Evolution of REM Dreaming. Anesthesia May Leave Patients Conscious—and Finally Show Consciousness in the Brain | The Crux. Alzheimer’s Spreads Like a Virus From Neuron to Neuron, Studies Show | 80beats. Why Did Consciousness Evolve, and How Can We Modify It? | Science Not Fiction. Amazing video shows us the actual movies that play inside our mind.
Scientists use brain imaging to reveal the movies in our mind. Scientists say they're getting closer to Matrix-style instant learning. Vision Scientists Demonstrate Innovative Learning Method. News - Video - Researchers explain Decoded Neurofeedback. Neuroimagen (III): Resonancia magnética, funcional y Conectoma. Bee swarms behave just like neurons in the human brain. What happens when your brain is split in two - and you survive? 10 Incredibly Strange Brain Disorders. Metaphors actually trigger the sensory parts of our brains.
"Teleported" mice reveal secrets of memory. Cómo aprende nuestro cerebro a base de ritmo. The Scientist Who Controlled People with Brain Implants. Jose Rodriguez Delgado: Implantes cerebrales - Vìdeo Dailymotion. How does your brain create short-term memories? Answer quickly: are there more fish on the left or right side of this image? Brain rhythms are key to learning. Why don't we normally hallucinate? How does our brain know what is a face and what’s not? Seeking the neurological roots of conflict. How scientists discovered the "fear center" of the brain. 10 Things You Probably Didn't Know About Dreams. Take a psychedelic trip through 700 layers of the human brain. A form of blindness where you can see everything, but recognize nothing. This is what your brain on drugs really looks like.
This is what your brain on drugs really looks like. Black and white TV generation have monochrome dreams. How exactly do neurons pass signals through your nervous system? Breakthrough: The first sound recordings based on reading people's minds. Why do people have phobias? Knowing a painting is forged changes how your brain sees it. ¿Por qué algunas melodías nos suenan mejores que otras?
Sweet Music to your Nerves | Physical Review Focus. El poderoso derrame de iluminación de Jill Bolte Taylor. Just How Free Is Free Will? | Innovations. Men Remember Repulsive Images, Women Pleasant Ones. As Social Network Grows, so Does the Brain | Social Networking, Brain Matter & Animal Dominance. Inside the Brain: A Journey Through Time | Brain Imaging Advances | Neurons & Neuroscience.
How the Brain Unscrambles Jumbled Letters | Why Poelpe Can Raed This, 4ND 7H15 | Why People Can Read Jumbled Words and Numbers In Place of Letters. What Falling in Love Does to the Brain | Love & the Brain. The Science of Sarcasm? Yeah, Right. Is a Memory Pill a Good Idea? | Innovations.