I once read that if the folds in the cerebral cortex were smoothed out it would cover a card table. That seemed quite unbelievable but it did make me wonder just how big the cortex would be if you ironed it out. I thought it might just about cover a family-sized pizza: not bad, but no card-table. I was astonished to realize that nobody seems to know the answer. A quick search yielded the following estimates for the smoothed out dimensions of the cerebral cortex of the human brain. An article in Bioscience in November 1987 by Julie Ann Miller claimed the cortex was a "quarter-metre square." That is napkin-sized, about ten inches by ten inches. Scientific American magazine in September 1992 upped the ante considerably with an estimated of 1 1/2 square metres; thats a square of brain forty inches on each side, getting close to the card-table estimate. A psychologist at the University of Toronto figured it would cover the floor of his living room (I haven't seen his living room), but the prize winning estimate so far is from the British magazine New Scientist's poster of the brain published in 1993 which claimed that the cerebral cortex, if flattened out, would cover a tennis court. How can there be such disagreement? How can so many experts not know how big the cortex is? I don't know, but I'm on the hunt for an expert who will say the cortex, when fully spread out, will cover a football field. A Canadian football field.
Recent brain scans have shed light on how the brain simulates the future. These simulation are done mainly in the dorsolateral prefrontal cortex, the CEO of the brain, using memories of the past. On one hand, simulations of the future may produce outcomes that are desirable and pleasurable, in which case the pleasure centers of the brain light up (in the nucleus accumbens and the hypothalamus). On the other hand, these outcomes may also have a downside to them, so the orbitofrontal cortex kicks in to warn us of possible dancers. There is a struggle, then, between different parts of the brain concerning the future, which may have desirable and undesirable outcomes. Ultimately it is the dorsolateral prefrontal cortex that mediates between these and makes the final decisions. (Some neurologists have pointed out that this struggle resembles, in a crude way, the dynamics between Freud's ego, id, and superego.)
We live in the Age of the Higher Brain, the cerebral cortex that has grown enormously over the last few millennia, overshadowing the ancient, instinctive lower brain. The cortex is often called the new brain, yet the old brain held sway in humans for millions of years, as it does today in most living things. The old brain can't conjure up ideas or read. But it does possess the power to feel and, above all, to be. It was the old brain that caused our forebears to sense the closeness of a mysterious presence everywhere in Nature.
How do we regulate our emotions? The answer is surprisingly simple: by thinking about them. The prefrontal cortex allows each of us to contemplate his or her own mind, a talent psychologists call metacognition. We know when we are angry; every emotional state comes with self-awareness attached, so that an individual can try to figure out why he's feeling what he's feeling. If the particular feeling makes no sense-if the amygdala is simply responding to a loss frame, for example-then it can be discounted. The prefrontal cortex can deliberately choose to ignore the emotional brain.
How do we regulate our emotions? The answer is surprisingly simple: by thinking about them. The prefrontal cortex allows each of us to contemplate his or her own mind, a talent psychologists call metacognition. We know when we are angry; every emotional state comes with self-awareness attached, so that an individual can try to figure out why he's feeling what he's feeling. If the particular feeling makes no sense""if the amygdala is simply responding to a loss frame, for example""then it can be discounted. The prefrontal cortex can deliberately choose to ignore the emotional brain.
Planning. Short-term memory. Attention. At first glance, these three frontal lobe functions can seem like diverse activities that just happen to be packed into the same brain region. But on closer inspection it turns out that they are facets of the same basic phenomenon of 'restraint'. Planning restrains our brains from wandering from a chosen path of activity. Short-term memory retrains sensory cortex from moving on to different imagery. Attention constrains the kind of sensory data admitted to sensory cortex.
The brain makes up l/50th of our body mass but consumes a staggering 1/5th of the calories we burn for energy. If your brain were a car, in terms of gas mileage, it'd be a Hummer. Most of our conscious activity is happening in our prefrontal cortex, the part of our brain responsible for focus, handling short-term memory, solving problems, and moderating impulse control. It's at the heart of what makes us human and the center for our executive control and willpower. The 'last in, first out' theory is very much at work inside our head. The most recent parts of our brain to develop are the first to suffer if there is a shortage of resources. Older, more developed areas of the brain, such as those that regulate breathing and our nervous responses, get first helpings from our blood stream and are virtually unaffected if we decide to skip a meal. The prefrontal cortex, on the other hand, feels the impact. Unfortunately, being relatively young in terms of human development, it's the runt of the litter come feeding time.
I studied neuroscience at the cellular level, so I was looking at learning and memory in the visual cortex of rats. Neuroscience mainly exposed me to a way of thinking - about experimentation, about what you believe to be true and how you could prove it - and how to approach things in a methodical manner.
There is no other species on Earth that does science. It is, so far, entirely a human invention, evolved by natural selection in the cerebral cortex for one simple reason: it works. It is not perfect. It can be misused. It is only a tool. But it is by far the best tool we have, self-correcting, ongoing, applicable to everything.
I am delighted that I have found a new reaction to demonstrate even to the blind the structure of the interstitial stroma of the cerebral cortex. I let the silver nitrate react with pieces of brain hardened in potassium dichromate. I have already obtained magnificent results and hope to do even better in the future.
I learned in the computer game business early on that all senses are not equal. The best example is, you're listening to a radio play and you're driving down the road, and suddenly you realize you haven't seen the road in five minutes. It's because your visual cortex has been partying with your imagination, basically.
The problem is, is when your focus is created by a crisis, then the frontal lobe shuts down essentially, the frontal cortex which is your intuitive intelligence. So you get very clever and very stupid in a crisis. Also, you pump adrenalin into your body from what you - physiologically you'll crash.
The ego is first and foremost a bodily ego; it is not merely a surface entity, but is itself the projection of a surface. If we wish to find an anatomical analogy for it we can best identify it with the 'cortical homunculus' of the anatomists, which stands on its head in the cortex, sticks up its heels, faces
For the first time in longer than I can remember, I feel peaceful. Not happy. Not sad. Not anxious. Not horny. Just all the higher parts of my brain closing up shop. The cerebral cortex. The cerebellum. That's where my problem is. I'm now simplifying myself. Somewhere balanced in the perfect middle between happiness and sadness. Because sponges never have a bad day.
One by one they are being picked off around him: in his small circle of colleagues the ratio slowly grows top-heavy, more ghosts, more each winter, and fewer living... and with each one, he thinks he feels patterns on his cortex going dark, settling to sleep forever, parts of whoever he's been losing all definition, reverting to dumb chemistry...
Grace was pouring out everywhere, from hidden sounds, into Els's damaged auditory cortex. And all that secret, worldwide composition said the same thing: listen closer, listen smaller, listen lighter, to any noise at all, and hear what the world will still sound like, long after your concert ends.
My space chums think my unique hookup with humanity could be evolution's awkward attempt to jump-start itself up again. They're thinking just maybe, going crazy could be the evolutionary process trying to hurry up mind expansion. Maybe my mind didn't snap. Maybe it was just trying to stretch itself into a new shape. The cerebral cortex trying to grow a thumb of sorts.
The relative importance of the white and gray matter is often misunderstood. Were it not for the manifold connection of the nerve cells in the cortex by the tens of millions of fibres which make up the under-estimated white matter, such a brain would be useless as a telephone or telegraph station with all the interconnecting wires destroyed.
Edward Anthony Spitzka
When Western people train the mind, the focus is generally on the left hemisphere of the cortex, which is the portion of the brainthat is concerned with words and numbers. We enhance the logical, bounded, linear functions of the mind. In the East, exercises of this sort are for the purpose of getting in tune with the unconscious--to get rid of boundaries, not to create them.
Edward T. Hall
The good part about having a mental disorder is having a valid reason for all the stupid things we do because of a damaged prefrontal cortex. However, the best part is seeing someone completely sane do the exact same things, without a valid excuse. This is the great equalizer of God and his little gift for all us crazy people to enjoy.
Shannon L. Alder
We, through the cerebral cortex, add the consciousness, spirit and rationality, to this dolphin brained human body avatar. We control our destiny and this body can become a servant of our conscious will, once we learn to communicate fully with it. We are called to bridge the gap between our conscious mind and the subconscious mind.
What distinguishes our species is thought. The cerebral cortex is in a way a liberation. We need no longer be trapped in the genetically inherited behavior patterns of lizards and baboons: territoriality and aggression and dominance hierarchies. We are each of us largely responsible for what gets put in to our brains. For what as adults we wind up caring for and knowing about. No longer at the mercy of the reptile brain we can change ourselves. Think of the possibilities.
Let me tell you, though: being the smartest boy in the world wasn't easy. I didn't ask for this. I didn't want this. On the contrary, it was a huge burden. First, there was the task of keeping my brain perfectly protected. My cerebral cortex was a national treasure, a masterpiece of the Sistine Chapel of brains. This was not something that could be treated frivolously. If I could have locked it in a safe, I would have. Instead, I became obsessed with brain damage.
A. J. Jacobs
Destiny is no more than the fulfillment of purposive potentialities within us. The human cerebral cortex is a single sheet composed of more neurons than there are stars in the known universe folded like a paper crane to fit in a quart-sized cubbyhole; there is enough potential energy in a single person that if released would equal thirty hydrogen bombs. Destiny is nothing to sneeze at!
The part of the brain most affected by early stress is the prefrontal cortex, which is critical in self-regulatory activities of all kinds, both emotional and cognitive. As a result, children who grow up in stressful environments generally find it harder to concentrate, harder to sit still, harder to rebound from disappointments, and harder to follow directions. And that has a direct effect on their performance in school.
You know, Vik, you're amazingly human at times. (Alix) I know. But I wonder if the feelings I have are real or just electrical stimulations in my cortex that simulate human emotion. I wish I knew if they were real or imagined. (Vik) And that makes you completely human, sweetie. We all have those doubts. (Alix)
If you are one of those people who can't hold a lot in mind at once-you lose focus and start daydreaming in lectures, and have to get to someplace quiet to focus so you can use your working memory to its maximum-well, welcome to the clan of the creative. Having a somewhat smaller working memory means you can more easily generalize your learning into new, more creative combinations. Because you're learning new, more creative combinations. Having a somewhat smaller working memory, which grows from the focusing abilities of the prefrontal cortex, doesn't lock everything up so tightly, you can more easily get input from other parts of your brain. These other areas, which include the sensory cortex, not only are more in tune with what's going on in the environment, but also are the source of dreams, not to mention creative ideas. You may have to work harder sometimes (or even much of the time) to understand what's going on, but once you've got something chunked, you can take that chunk and turn it outside in and inside round-putting it through creative paces even you didn't think you were capable of! Here's another point to put into your mental chunker: Chess, that bastion of intellectuals, has some elite players with roughly average IQs. These seemingly middling intellects are able to do better than some more intelligent players because they practice more. That's the key idea. Every chess player, whether average or elite, grows talent by practicing. It is the practice-particularly deliberate practice on the toughest aspects of the material-that can help lift average brains into the realm of those with more 'natural' gifts. Just as you can practice lifting weights and get bigger muscles over time, you can also practice certain mental patterns that deepen and enlarge in your mind.
There is one brain organ that is optimised for understanding and articulating logical processes and that is the outer layer of the brain, called the cerebral cortex. Unlike the rest of the brain, this relatively recent evolutionary development is rather flat, only about 0.32 cm (0.12 in) thick and includes a mere 6 million neurons. This elaborately folded organ provides us with what little competence we do possess for understanding what we do and who we do it.
the parts of the brain corresponding to the limbic system (thought to respond only to more visceral, immediate rewards) were activated only when the decision involved comparing a reward today with one in the future. In contrast, the lateral prefrontal cortex (a more 'calculating' part of the brain) responded with a similar intensity to all decisions, regardless of the timing of the options. Brains that work like this would produce a lot of failed good intentions. And indeed, we do see a lot of those, from New Year's resolutions to gym memberships that lie unused.
Abhijit V. Banerjee
We are part of nature, a product of a long evolutionary journey. To some degree, we carry the ancient oceans in our blood. ... Our brains and nervous systems did not suddenly spring into existence without long antecedents in natural history. That which we most prize as integral to our humanity - our extraordinary capacity to think on complex conceptual levels - can be traced back to the nerve network of primitive invertebrates, the ganglia of a mollusk, the spinal cord of a fish, the brain of an amphibian, and the cerebral cortex of a primate.
There will come a time when a person you most likely pushed out through your vagina and nursed from your nipples, whose bottom you wiped, and whose snot and spit you cleaned up over several sleep-starved years will apprehend you with a mixture of boredom and irritation and say, 'Get a life, Mum.' This would be a good time to remember that a) violence never solved anything; b) teenagers don't have a full brain yet - the prefrontal cortex that controls the ability to make important distinctions, like who controls the pocket money, only kicks in around the age of twenty-four; and c) you are, in fact, the adult.
Despite their differences, pride, shame, and guilt all activate similar neural circuits, including the dorsomedial prefrontal cortex, amygdala, insula, and the nucleus accumbens. Interestingly, pride is the most powerful of these emotions at triggering activity in these regions - except in the nucleus accumbens, where guilt and shame win out. This explains why it can be so appealing to heap guilt and shame on ourselves - they're activating the brain's reward center.
David D. Burns
Each time we check a Twitter feed or Facebook update, we encounter something novel and feel more connected socially (in a kind of weird impersonal cyber way) and get another dollop of reward hormones. But remember, it is the dumb, novelty-seeking portion of the brain driving the limbic system that induces this feeling of pleasure, not the planning, scheduling, higher-level thought centers in the prefrontal cortex. Make no mistake: E-mail, Facebook, and Twitter checking constitute a neural addiction
Daniel J. Levitin
Warning: This data storage unit, or "book, " has been designed to reprogram the human brain, allowing it to replicate the lost art that was once called reading. It is a simple adjustment and there will be no negative or harmful effects from this process. What you are doing: "Reading" Explained Each sheet is indelibly printed with information and the sheets are visually scanned from left to right, and from top to bottom. This scanned information is passed through the visual cortex directly into the brain, where it can then be accessed just like any other data.
Mike A. Lancaster
Most people don't see half of what's in front of them. Your visual cortex does a shit load of imaging processing before the signal even gets to your brain, whose priorities are still checking the ancestral Savannah for dangerous predators, edible berries and climable trees. That's why a sudden cat in the night can make you jump and some people when distracted, can walk right out in front of a bus. Your brain just isn't interested in those large moving chunks of metal or the static heaps of brightly colored stuff that piles up in drifts around us. Never mind all that, says your brain, it's those silent fur-covered merchants of death you've got to watch out for.
Inside any man resides a wild beast, of course, if he holds a true male brain. More precisely, amygdala-part of any brain, which is larger in men, takes the responsibility for it. It can be tamed by Prefrontal Cortex, another part of the brain, which regulates the emotions and keeps them from going wild, and which is larger in women. Men's mature wisdom, in most cases, is a mask that hides a wild beast, and it is not a result of tamed instincts. Naked truth is that men are wild beasts born and only fear of being punished prevent them against being such.
Classifying depression as an illness serves the psychiatric community and pharmaceutical corporations well; it also soothes the frightened, guilty, indifferent, busy, sadistic, and unschooled. To understand depression as a call for life-changes is not profitable. Stagnation is not a medical term. The 17.5 million Americans diagnosed as suffering a major depression in 1997 were mostly damned. (Psychobiological examinations confuse cause and symptom.) Deficient serotonergic functioning, ventral prefrontal cerebral cortex, dis-inhibition of impulsive-aggressive behavior, blah blah blah: the medical lexicon boils emotion from human being. Go take a drug, the doctor says. Pain is a biochemical phenomenon. Erase all memory.
As the language areas of the left hemisphere enter their sensitive period during the middle of the second year of life, grammatical language in the left integrates with the interpersonal and prosodic elements of communication already well developed in the right. As the cortical language centers mature, words are joined together to make sentences and can be used to express increasingly complex ideas flavored with emotion. As the frontal cortex continues to expand and connect with more neural networks, memory improves and a sense of time slowly emerges and autobiographical memory begins to connect the self with places and events, within and across time. The emerging narratives begin to organize the nascent sense of self and become the bedrock of our sense of self in interpersonal and physical space
Our visual field, the entire view of what we can see when we look out into the world, is divided into billions of tiny spots or pixels. Each pixel is filled with atoms and molecules that are in vibration. The retinal cells in the back of our eyes detect the movement of those atomic particles. Atoms vibrating at different frequencies emit different wavelengths of energy, and this information is eventually coded as different colors by the visual cortex in the occipital region of our brain. A visual image is built by our brain's ability to package groups of pixels together in the form of edges. Different edges with different orientations - vertical, horizontal and oblique, combine to form complex images. Different groups of cells in our brain add depth, color and motion to what we see.
Jill Bolte Taylor
The Happiest Man in The World The French interpreter for the 14th Dalai Lama, former academic and dedicated meditator Matthieu Ricard, came into the spotlight in the field of neural science after being named 'the happiest man in the world'. Naturally, there are many other men and women who demonstrate such equanimity, but the studies on his brain uncovered truly astonishing results. MRI scans showed that Matthieu Ricard and other serious long-term meditators (with more than 10, 000 hours of practice each) were mentally, emotionally and spiritually fulfilled and displayed an abundance of positive emotions and equanimity in the left pre-frontal cortex of the brain. When talking about his mindfulness training, Matthieu Ricard said with humility that: 'Happiness is a skill. It requires effort and time'.
Commenting acidly on a writer whom I perhaps too naively admired, my old classics teacher put on his best sneer to ask: 'Wouldn't you say, Hitchens, that his writing was somewhat journalistic?' This lofty schoolmaster employed my name sarcastically, and stressed the last term as if he meant it to sting, and it rankled even more than he had intended. Later on in life, I found that I still used to mutter and improve my long-meditated reply. e‰mile Zola-a journalist. Charles Dickens-a journalist. Thomas Paine-another journalist. Mark Twain. Rudyard Kipling. George Orwell-a journalist par excellence. Somewhere in my cortex was the idea to which Orwell himself once gave explicit shape: the idea that 'mere' writing of this sort could aspire to become an art, and that the word 'journalist'-like the ironic modern English usage of the word 'hack'-could lose its association with the trivial and the evanescent.
Think of cocaine. In its natural form, as coca leaves, it's appealing, but not to an extent that it usually becomes a problem. But refine it, purify it, and you get a compound that hits your pleasure receptors with an unnatural intensity. That's when it becomes addictive. Beauty has undergone a similar process, thanks to advertisers. Evolution gave us a circuit that responds to good looks - call it the pleasure receptor for our visual cortex - and in our natural environment, it was useful to have. But take a person with one-in-a-million skin and bone structure, add professional makeup and retouching, and you're no longer looking at beauty in its natural form. You've got pharmaceutical-grade beauty, the cocaine of good looks. Biologists call this "supernormal stimulus" [... ] Our beauty receptors receive more stimulation than they were evolved to handle; we're seeing more beauty in one day than our ancestors did in a lifetime. And the result is that beauty is slowly ruining our lives. How? The way any drug becomes a problem: by interfering with our relationships with other people. We become dissatisfied with the way ordinary people look because they can't compare to supermodels.
Uncouth, clannish, lumbering about the confines of Space and Time with a puzzled expression on his face and a handful of things scavenged on the way from gutters, interglacial littorals, sacked settlements and broken relationships, the Earth-human has no use for thinking except in the service of acquisition. He stands at every gate with one hand held out and the other behind his back, inventing reasons why he should be let in. From the first bunch of bananas, his every sluggish fit or dull fleabite of mental activity has prompted more, more; and his time has been spent for thousands of years in the construction and sophistication of systems of ideas that will enable him to excuse, rationalize, and moralize the grasping hand. His dreams, those priceless comic visions he has of himself as a being with concerns beyond the material, are no more than furtive cannibals stumbling round in an uncomfortable murk of emotion, trying to eat each other. Politics, religion, ideology - desperate, edgy attempts to shift the onus of responsibility for his own actions: abdications. His hands have the largest neural representation in the somesthetic cortex, his head the smallest; but he's always trying to hide the one behind the other.
M. John Harrison
These computer simulations try only to duplicate the interactions between the cortex and the thalamus. Huge chunks of the brain are therefore missing. Dr. [Dharmendra] Modha understands the enormity of his project. His ambitious research has allowed him to estimate what it would take to create a working model of the entire human brain, and not just a portion or a pale version of it, complete with all parts of the neocortex and connections to the senses. He envisions using not just a single Blue Gene computer [with over a hundred thousand processors and terabytes of RAM] but thousands of them, which would fill up not just a room but an entire city block. The energy consumption would be so great that you would need a thousand-megawatt nuclear power plant to generate all the electricity. And then, to cool off this monstrous computer so it wouldn't melt, you would need to divert a river and send it through the computer circuits. It is remarkable that a gigantic, city-size computer is required to simulate a piece of human tissue that weighs three pounds, fits inside your skull, raises your body temperature by only a few degrees, uses twenty watts of power, and needs only a few hamburgers to keep it going.
As information processing machines, our ability to process data about the external world begins at the level of sensory perception. Although most of us are rarely aware of it, our sensory receptors are designed to detect information at the energy level. Because everything around us - the air we breathe, even the materials we use to build with, are composed of spinning and vibrating atomic particles, you and I are literally swimming in a turbulent sea of electromagnetic fields. We are part of it. We are enveloped within in, and through our sensory apparatus we experience what is. Each of our sensory systems is made up of a complex cascade of neurons that process the incoming neural code from the level of the receptor to specific areas within the brain. Each group of neurons along the cascade alters or enhances the code, and passes it on to the next set of cells in the system, which further defines and refines the message. By the time the code reaches the outermost portion of our brain, the higher levels of the cerebral cortex, we become conscious of the stimulation. However, if any of the cells along the pathway fail in their ability to function normally, then the final perception is skewed away from normal reality.
Jill Bolte Taylor