Brain



"We found evidence that anxious individuals devoted more brain processing resources, especially in parts of the brain involved in working memory such as the prefrontal and parietal cortex, to threat stimuli that they were supposed to ignore rather than remember,” Stout explained. “This suggests that while non-anxious individuals can successfully prevent this threat information that is not related to the task at hand from entering working memory, anxious individuals are not effectively ignoring this information.”

“Also, we hypothesize that once this threat information enters working memory it may have downstream consequences, such as leading to more anxious thoughts and increasing anxiety. However, this has yet to be tested. If that were to be the case then designing treatments that would help anxious individuals better ignore potential threats and prevent them from being hashed over in working memory would be potentially helpful in ameliorating anxiety.”



Theory of mind is the ability to differentiate one’s own perspective and preferences from someone else’s. A classic experiment in theory of mind is known as the Sally-Anne test, in which a child is told Sally has a basket and Anne has a box. Sally puts an object in her basket, then leaves. While Sally is gone, Anne moves the object to the box.

The child is then asked where Sally will look for the object when she returns. Correctly answering that Sally will look in her basket signals the child understands they have a perspective that is different from Sally's.

Theory of mind is important for developing empathy, making friends and even doing well academically, Lytle said. Parents can help their children develop perspective by talking them through scenarios like the Sally-Anne test or reading books that help them to build cognitive parallels, she said. For example, in a book where a character goes to a doctor, they can compare the situation to when the child went to the doctor and discuss how the experiences were similar or different.



The brain's reward system - sociability, sex, drugs, and sugar












In the latest study, researchers honed in on the neural network structures within the brain using algebraic topology—a system used to describe networks with constantly changing spaces and structures. This is the first time this branch of math has been applied to neuroscience. They discovered that when they presented the virtual tissue with stimulus, groups of neurons form a clique. Each neuron connects to every other neuron in a very specific way to produce a precise geometric object. The more neurons in a clique, the higher the dimensions. The structures assembled formed enclosures for high-dimensional holes that the team have dubbed cavities. Once the brain has processed the information, the clique and cavity disappears.

Henry Markram, director of Blue Brain Project, said the findings could help explain why the brain is so hard to understand. "The mathematics usually applied to study networks cannot detect the high-dimensional structures and spaces that we now see clearly,” he said. "We found a world that we had never imagined. There are tens of millions of these objects even in a small speck of the brain, up through seven dimensions. In some networks, we even found structures with up to eleven dimensions."

“The stereotypical response pattern that we discovered indicates that the circuit always responds to stimuli by constructing a sequence of geometrical representations starting in low dimensions and adding progressively higher dimensions, until the build-up suddenly stops and then collapses: a mathematical signature for reactions to stimuli.



Studies in animal models have shown that new neurons are produced in the brain throughout the lifespan, and, so far, only one activity is known to trigger the birth of those new neurons: vigorous aerobic exercise, said Karen Postal, president of the American Academy of Clinical Neuropsychology. “That’s it,” she said. “That’s the only trigger that we know about.”

The other fascinating thing here is where these new cells pop up: in the hippocampus, a region of the brain associated with learning and memory. So this could help explain, at least partially, why so many studies have identified a link between aerobic exercise and improvement in memory. “If you are exercising so that you sweat — about 30 to 40 minutes — new brain cells are being born,” added Postal, who herself is a runner. “And it just happens to be in that memory area.”

Other post-run changes have been recorded in the brain’s frontal lobe, with increased activity seen in this region after people adopt a long-term habit of physical activity. This area of the brain — sometimes called the frontal executive network system — is located, obviously enough, at the very front: It’s right behind your forehead. After about 30 to 40 minutes of a vigorous aerobic workout – enough to make you sweat – studies have recorded increased blood flow to this region, which, incidentally, is associated with many of the attributes we associate with “clear thinking”: planning ahead, focus and concentration, goal-setting, time management.



Research has found that mindfulness training alters our brains and how we engage with ourselves, others, and our work. When practiced and applied, mindfulness fundamentally alters the operating system of the mind. Through repeated mindfulness practice, brain activity is redirected from ancient, reactionary parts of the brain, including the limbic system, to the newest, rational part of the brain, the prefrontal cortex.

In this way mindfulness practice decreases activity in the parts of the brain responsible for fight-or-flight and knee-jerk reactions while increasing activity in the part of the brain responsible for what’s termed our executive functioning. This part of the brain, and the executive functioning skills it supports, is the control center for our thoughts, words, and actions. It’s the center of logical thought and impulse control. Simply put, relying more on our executive functioning puts us firmly in the driver’s seat of our minds, and by extension our lives.



The Quiet Leadership Institute, in partnership with the University of Pennsylvania’s Scott Barry Kaufman, developed the assessment through months of rigorous testing and analysis. From this research, we determined that introversion and extroversion can best be explained through the facets of stimulation and deliberation. Stimulation measures your preference for environments that are either calm or exciting. Deliberation measures your preference for deliberation vs. action.

Given the choice, you’ll devote your social energy to a small group of people you care about most, preferring a glass of wine with a close friend to a party full of strangers. You think before you speak, have a more deliberate approach to risk, and enjoy solitude. You feel energized when focusing deeply on a subject or activity that really interests you. When you’re in overly stimulating environments (too loud, too crowded, etc.) you tend to feel overwhelmed. You seek out environments of peace, sanctuary, and beauty; you have an active inner life and are at your best when you tap into its riches.







Researchers examined the role of a group of neurons in the part of the brain known as the hypothalamus. The agouti-related neuropeptide, or AGRP, neurons regulate appetite and when activated make you eat and when fully inhibited, can lead to anorexia.

"Our findings suggest that a group of neurons in the brain coordinate appetite and energy expenditure, and can turn a switch on and off to burn or spare calories depending on what's available in the environment," Blouet said. "If food is available, they make us eat, and if food is scarce, they turn our body into saving mode and stop us from burning fat."

The study was published in eLife.



To move through fear and self-criticism in a way that genuinely changes how one relates to the world, to change not just one’s thoughts, but one’s experience and perception — that is a major feat, whether done as an adult or a child, and whether that process occurs in 10 minutes or 10 years.

I believe that miracles only contradict what we know of nature at this point in time. Modern physics is, for example, way ahead of traditional science, and its implications have not been fully incorporated into its perspectives and methods yet. So I believe that miracles actually are consistent with mental and spiritual laws that we are only beginning to study. This is the only way I can understand the similarities among all those with remarkable recoveries whom I have been interviewing.



While the descriptions of the subjective experience of ego dissolution are illuminating, neuroscience studies are revealing the cognitive underpinnings of the phenomenon. A 2016 study, which used functional Magnetic Resonance Imaging (fMRI) to peer inside the brains of participants tripping on acid, discovered the neural mechanisms underlying temporary ego loss. They found that ego dissolution occurs when there is increased global connectivity between regions of the brain involved in higher cognition. This means that when participants were ‘tripping,’ communication between brain areas that are normally very distinct in their activity opened up, and the level of communication among these areas was positively correlated with the reported degree of ego dissolution experienced. Specifically, there was greater connectivity between sensory areas of the brain and a region associated with self-consciousness, called the frontoparietal cortex.



The genes responsible for red and green cone cells are located on the X-chromosome. An individual genetic variation responsible for tetrachromacy would need two copies in order for the trait to be expressed. As such, it is assumed that because men only have one X-chromosome, only women are capable of being tetrachromats. On the flip side, this is also why men are more likely to be colorblind than women. Men don’t have a backup in case they receive a faulty copy of those genes. Women, on the other hand, would need to inherit two copies to code for color blindness.

Testing for tetrachromacy can be a bit difficult, as most tests are based on trichromatic vision. Genetic analysis revealed Antico does have the genetic variations that allow for a fourth type of cone cell. Though this mutation has given her an incredible gift of expanded color perception, it has left her daughter colorblind.







After nine generations of evolution in the laboratory, the researchers measured the sizes of the brains of the male and female fish from all their selection lines and from unselected control lines. They found that in the lines where males were selected to have longer gonopodia, the females had evolved larger brains that were around 6% heavier than the brains of females from the other lines.

What seems to be happening is that, when sexual conflict is most intense, females who can use their brains to avoid coercive mating are actually the most successful at reproducing. This could be because these clever females are harassed less and can get on with things like feeding, or because they are better able to select the best quality males to father their offspring.

These results suggest that conflict between the sexes can, at least in this case, cause the evolution of larger brains. But how general might this process be? Species where the males are this boorish and aggressive towards females are, thankfully, infrequent, and there are plenty other important evolutionary factors which can also lead to the evolution of bigger brains. For example, living in large, complicated social groups seems to require bigger brains (the so-called "social brain hypothesis").






FLOW

Flow — the mental state of being completely present and fully immersed in a task — is a strong contributor to creativity. When in flow, the creator and the universe become one, outside distractions recede from consciousness and one’s mind is fully open and attuned to the act of creating. There is very little self-awareness or critical self-judgement; just intrinsic joy for the task.

The researchers also found an association between flow and conscientiousness. Those who were more dutiful and persevering also tended to report higher levels of flow in their daily lives. This association is probably due to the fact that conscientiousness is positively related to other variables that are also associated with flow, such as social problem solving, life satisfaction, subjective happiness, positive affect and intrinsic motivation. Conscientious individuals are also more likely to spend the time practicing to master challenging tasks, conditions which make flow more likely. As the researchers note, “It seems likely that high conscientiousness involves emotional and motivational mechanisms that make an individual engage in flow promoting activities.”

🙏 ॐ 🙏

In a recent large review, Rex Jung and colleagues provide a "first approximation" regarding how creative cognition might map on to the human brain. Their review suggests that when you want to loosen your associations, allow your mind to roam free, imagine new possibilities, and silence the inner critic, it's good to reduce activation of the Executive Attention Network (a bit, but not completely) and increase activation of the Imagination and Salience Networks. Indeed, recent research on jazz musicians and rappers engaging in creative improvisation suggests that's precisely what is happening in the brain while in a flow state.

Also, converging research findings do suggest that creative cognition recruits brain regions that are critical for daydreaming, imagining the future, remembering deeply personal memories, constructive internal reflection, meaning making, and social cognition.



CREATIVITY


Evolutionary biologist Joe Henrich of the University of British Columbia, who recently wrote a book on the role of culture in the success of our species, expects that will indeed turn out to be the case. “I think the idea that innovation depends on individual geniuses is misguided. History shows that inventions invariably build on earlier findings that are recombined and improved upon. Most of the things we use every day are inventions that no single human being could ever design within her lifetime,” he observes. “Rather than the product of individual innovators, these inventions can be thought of as the product of our societies. Innovations rely on individuals learning from others—in that way, human society functions like a collective brain.”



Magnetite can occur naturally in the brain in tiny quantities but the particles formed that way are distinctively jagged. By contrast, the particles found in the study were not only far more numerous but also smooth and rounded - characteristics that can only be created in the high temperatures of a vehicle engine or braking systems. For every one natural magnetite particle identified, the researchers found about 100 of the pollution-derived ones.

Dubbed "nanospheres", the particles are less than 200 nanometres in diameter - by comparison, a human hair is at least 50,000 nanometres thick. While large particles of pollution such as soot can be trapped inside the nose, smaller types can enter the lungs and even smaller ones can cross into the bloodstream. But nanoscale particles of magnetite are believed to be small enough to pass from the nose into the olfactory bulb and then via the nervous system into the frontal cortex of the brain.




“What or who is having this experience right this moment, right now? It is your own being. It is your innermost being that is having the experience, your true self. Live here, with no regrets, no anticipation, no resistance, and you will be free. Freedom is always now. Being is now.”



Motion sickness: "So what’s happening there is the brain’s getting mixed messages. It’s getting signals from the muscles and the eyes saying we are still and signals from the balance sensors saying we’re in motion. Both of these cannot be correct. There’s a sensory mismatch there. And in evolutionary terms, the only thing that can cause a sensory mismatch like that is a neurotoxin or poison. So the brain thinks, essentially, it’s been being poisoned. When it’s been poisoned, the first thing it does is get rid of the poison, a.k.a. throwing up."

Preventions writes that this health trick has been shown in 40 studies to effectively reduce nausea from motion sickness: Press between the two tendons on the inside of your wrist, about three finger breadths below the base of your palm. Try it for about 30 seconds and you may feel immediately better, but some people may need several minutes. This technique may also help relieve anxiety.

In addition to medication and the soothing properties of ginger, opening a window isn't a bad idea. Cooler temperatures might also help, said Dr. Joseph M. Furman, a professor of otolaryngology and neurology at University of Pittsburgh Medical Center, who used to drive with the windows cracked in winter to soothe his son who was in elementary school.



A study printed in The Quarterly Journal of Experimental Psychology claims that talking to yourself makes your brain work more efficiently. Talking through things aloud can help organize your thoughts, as well as validate difficult decisions, according to psychologist Linda Sapadin. “It helps you clarify your thoughts, tend to what’s important, and firm up any decisions you’re contemplating.”

Talking to yourself about your goals also helps you attain them. It turns out saying your goals aloud is even better for achieving them than making a written list, which can seem daunting. As Sapadin says, "Saying your goals out loud focuses your attention, reinforces the message, controls your runaway emotions, and screens out distractions.”



Lead author of the study Professor Roger Whitaker, from Cardiff University's School of Computer Science and Informatics, said: "Our results suggest that the evolution of cooperation, which is key to a prosperous society, is intrinsically linked to the idea of social comparison -- constantly sizing each up and making decisions as to whether we want to help them or not.

"We've shown that over time, evolution favors strategies to help those who are at least as successful as themselves."



Findings from a Florida Gulf Coast University study seem to support the idea that people with a high IQ get bored less easily, leading them to spend more time engaged in thought. And active people may be more physical as they need to stimulate their minds with external activities, either to escape their thoughts or because they get bored quickly.

But the weekends showed no difference between the two groups, something which has not been able to be explained. Researchers suggested the findings could lend weight to the idea that non-thinkers get bored more easily, so need to fill their time with physical activity. He suggested that the less active people, no matter how clever they are, should aim to raise their overall activity levels to improve their health.

The British Psychological Society quoted the study, saying: "Ultimately, an important factor that may help more thoughtful individuals combat their lower average activity levels is awareness. Awareness of their tendency to be less active, coupled with an awareness of the cost associated with inactivity, more thoughtful people may then choose to become more active throughout the day."







It's crucial that we use our ability to reflect and think deliberately not to introspect, but to become more mindful. This is an important distinction. Introspection involves asking questions, yet we've seen that we'll tend to answer those questions in a self-serving way. As Nietzsche hinted in Twilight of the Idols, "We want to have a reason for feeling as we do... it never suffices us simply to establish the mere fact that we feel as we do." Mindfulness, in contrast, involves observing without questioning. If the takeaway from research on cognitive biases is not simply that thinking errors exist but the belief that we are immune from them, then the virtue of mindfulness is pausing to observe this convoluted process in a non-evaluative way. We spend a lot of energy protecting our egos instead of considering our faults. Mindfulness may help reserve this.



"Studies have found that people who take 15-minute breaks every couple of hours end up being more productive, says Levitin. But these breaks must allow for mind-wandering, whether you’re walking, staring out the window, listening to music or reading. “Everyone gets there a different way. But surfing Facebook is not one of them,” he says. Social networks just produce more fractured attention, as you flit from one thing to the next.

Gloria Mark, professor in the department of informatics at the University of California, Irvine, says that when people are interrupted, it typically takes 23 minutes and 15 seconds to return to their work, and most people will do two intervening tasks before going back to their original project. This switching leads to a build up of stress, she says, and so little wonder people who have high rates of neuroticism, impulsivity, and are susceptible to stress tend to switch tasks more than others."



“Consciousness is the brain’s non-conceptual theory about itself, gained through experience—that is learning, interacting with itself, the world, and with other people,” he says.

In the paper where he puts forward his thesis, Cleeremans argues that in order to be aware, it’s necessary not simply to know information, but to know that one knows information. In other words, unlike a thermostat that simply records temperature, conscious humans both know and care that they know. Cleeremans claims that the brain is continually and unconsciously learning to re-describe its own activity to itself, and these descriptions form the basis of conscious experience.



Back in 1967, the psychologist Martin Seligman conducted a famous psychological experiment at the University of Pennsylvania. He administered shocks to two sets of dogs. The first set could stop the shocks by pressing a lever, or, later jumping over a low partition. The second set had no control over the frequency or duration of the shocks. Even when these subjects were given the chance to jump over the partition, they lay down passively and whined as shocks were administered.

Seligman’s experiment was a vivid confirmation of what psychologists call learned helplessness. Sociologists have since suggested that this concept governs societies as well as individuals. When a political culture cannot achieve desired goals, voters fall into a state of debility, dependency, and dread. This, in a nutshell, is the current state of the American electorate, though the more precise term is probably learned hopelessness.

"It turns out that the dogs suffering from learned helplessness—the ones being shocked on an electrified grid—were not swayed by threat, rewards, or even observed demonstrations of how they might escape. The only thing that worked, Seligman found, was for his experimenters to physically pick the dogs up and move their legs in such a way as to replicate how they might escape. This had to be done at least twice before the dogs would rescue themselves on their own."



Live mouse's dentate gyrus, responsible for learning and memory. Red-labeled young neurons.

"The researchers found that the younger neurons were more excitable than the mature neurons, firing off more indiscriminately. But that excitable period didn't last long. After about six weeks, the neurons became more precise, like their mature counterparts. This excitable period might be the key to forming memories about new experiences. When using optogenetics--which can turn light-sensitive neurons on or off using light--to silence the younger neurons, the mice were unable to remember which treadmill experience was pleasant and which was accompanied by the unpleasant shocks. Instead, the mice with the silenced neurons feared both unknown scenarios."



"Path dependency is an idea that tries to explain the continued use of a product or practice based on historical preference or use. This holds true even if newer, more efficient products or practices are available due to the previous commitment made. Path dependency occurs because it is often easier or more cost effective to simply continue along an already set path than to create an entirely new one."







Eldar Shafir, Ph.D. (professor of psychology and public affairs at Princeton): “When we attend to one thing, we attend much less to something else.”



"The human brain is capable of 1016 processes per second, which makes it far more powerful than any computer currently in existence. But that doesn't mean our brains don't have major limitations. A cognitive bias is a genuine deficiency or limitation in our thinking — a flaw in judgment that arises from errors of memory, social attribution, and miscalculations (such as statistical errors or a false sense of probability). Some social psychologists believe our cognitive biases help us process information more efficiently, especially in dangerous situations. Still, they lead us to make grave mistakes."



Cryptamnesia (unconscious plagiarism): "—a phenomenon, I guess, familiar to all of us, when what we experience as our own brilliant idea has actually been unknowingly adopted from something we have read or heard."



“People still don’t get it,” actress Alfre Woodard said. “They think it’s play time. They think it’s touchy feel-y. But it’s undeniable what music, painting, [and] movement do to the brain. It becomes more receptive to scientific ideas.” Damian Woetzel's vision is “to give kids the tools to become adults who are creative, adaptable, and collaborative, expressive—capable of having their eyes and ears and senses alive.”



"Out in public, Dr. Steiner-Adair added, “children have to know that life is fine off the screen. It’s interesting and good to be curious about other people, to learn how to listen. It teaches them social and emotional intelligence, which is critical for success in life.”

Children who are heavy users of electronics may become adept at multitasking, but they can lose the ability to focus on what is most important, a trait critical to the deep thought and problem solving needed for many jobs and other endeavors later in life."



"Children tend to fall within a spread of 13 IQ points above and below the average IQ of their parents. But sometimes the apple can fall twice as far from the tree—that is, two parents with 100 IQs producing a child with an IQ of 126. Hsu puts the chance of such a positive outlier at around 2 or 3 percent, and it depends mostly on which sperm meets which egg."



"In a recent study, a team of psychologists from the Northumbria University in the UK found that particular teas impact different cognitive functions. Specifically, their research revealed that peppermint tea helped improve working memory and long-term memory, whereas chamomile tea significantly significantly slowed memory and attention speed."







Joie de vivre is a French phrase often used in English to express a cheerful enjoyment of life; an exultation of spirit. It "can be a joy of conversation, joy of eating, joy of anything one might do… And joie de vivre may be seen as a joy of everything, a comprehensive joy, a philosophy of life, a Weltanschauung. Robert's Dictionnaire says joie is sentiment exaltant ressenti par toute la conscience, that is, involves one's whole being."

Expressing one's creativity, quest for spiritual enlightenment, pursuit of knowledge, and the desire to give to society are examples of self-actualization. In Goldstein's view, it is the organism's master motive, the only real motive: "the tendency to actualize itself as fully as possible is the basic drive... the drive of self-actualization." Carl Rogers similarly wrote of "the curative force in psychotherapy – man's tendency to actualize himself, to become his potentialities... to express and activate all the capacities of the organism."




"Previous work by Saldanha and his colleagues explored how hormones communicate with neurons. They discovered a new method of communication, synaptocrine signaling, by which neurons create and feed high levels of estrogen to one another. That’s when they also discovered which cells were synthesizing estrogen under conditions of brain injury: the glial cells, which are important, non-neuronal cells that live in the brain.

The release of estrogen in the brain to control inflammation is a natural process. It happens within about 24 hours in songbirds. The same process occurs in mammals over several days – perhaps far too late to stop brain degeneration or an end to life. In the current experiments, Saldanha discovered another important function of glial cells — that they activated the rapid response to protect the birds’ brains. However more needed to be understood about how the protective process was keeping inflammation in check."




"The researchers then showed that while the mice cannot recall their experiences when prompted by natural cues, those memories are still there. To demonstrate this, they first tagged the engram cells associated with the fearful experience with a light-sensitive protein called channelrhodopsin, using a technique they developed in 2012. Whenever these tagged engram cells are activated by light, normal mice recall the memory encoded by that group of cells. Likewise, when the researchers placed the Alzheimer's mice in a chamber they had never seen before and shined light on the engram cells encoding the fearful experience, the mice immediately showed fear.

The researchers also showed that the engram cells of Alzheimer's mice had fewer dendritic spines, which are small buds that allow neurons to receive incoming signals from other neurons. The researchers were also able to induce a longer-term reactivation of the "lost" memories by stimulating new connections between the entorhinal cortex and the hippocampus.



"If you can transplant cells in a way that mimics how these cells are already configured in the brain, then you're one step closer to getting the brain to communicate with the cells that you're now transplanting," said Moghe, research director for the School of Engineering/Health Sciences Partnerships at Rutgers. "In this work, we've done that by providing cues for neurons to rapidly network in 3-D."

Moghe said a 3-D scaffold, developed by the scientists, consists of tiny polymer fibers. Hundreds of neurons attach to the fibers and branch out, sending their signals. Scaffolds are about 100 micrometers wide - roughly the width of a human hair... Indeed, the scaffold technology results in a 100-fold increase in cell survival over other methods, Moghe said.



"Simply blocking this pathway shouldn't have an effect on its strength," says Agnès Gruart from University Pablo Olavide. "When we investigated further, we discovered that activity in one of the other pathways was driving this weakening."

Interestingly, this active push for forgetting only happens in learning situations. When the scientists blocked the main route into the hippocampus under other circumstances, the strength of its connections remained unaltered.

"One explanation for this is that there is limited space in the brain, so when you're learning, you have to weaken some connections to make room for others," says Gross. "To learn new things, you have to forget things you've learned before."



During learning, the number of synapses onto interneurons was found to double along hippocampal mossy fibers. These new synapses indirectly inhibited other cells, known as pyramidal neurons, thereby contributing to the precision of what was learned. They thus laid down, for example, that at a certain point in the maze, the mouse should go to the right, but not to the left, straight ahead, back, up, or down. When the formation of these synapses was inhibited by the administration of a drug, the mouse would still find its way, but with less precision - it did not take the shortest route to the goal.

Caroni explains: "Our experiments have, for the first time, demonstrated a clear association between the formation of new synapses and behavior after learning. So we've shown a specific structural change in the brain induced by learning - and also that this change is required for the precision of learning."



A much more recent 2008 study published in the journal Social and Personality Psychology Compass by psychologist Jennifer Bosson of the University of South Florida, affirmed both the power and the pain of mask model narcissism. “The mask model offers an appealing answer to why narcissists behave as they do,” Bosson wrote. “Narcissists self-aggrandize, manipulate, derogate and exploit because deep down inside they actually dislike themselves. Not only does this answer make intuitive sense to many, it also fits nicely with current thinking about people’s introspective access to their own inner selves.”




"Previous studies had shown that neurons called place cells in the hippocampus become associated with particular places when rats explore mazes. During breaks when animals are inactive, they replay these place experiences in their minds (CA2). The place cells that activated while exploring the maze fire again in the same sequence, but on a much faster timescale. This is reflected in telltale split-second bursts of electrical activity called sharp-wave ripples (SWRs), in the hippocampus.

When they examined activity in groups of neurons in the two regions simultaneously as rats were learning spatial tasks, Jadhav and Rothschild’s team saw coordinated reactivation [associated with slow, rhythmic theta oscillations] during SWRs spanning both the hippocampus (CA1) and the prefrontal cortex (PFC). In the PFC, they were surprised to see that this reactivation involved both excitation as well as inhibition of functionally distinct populations of neurons. Within a particular SWR, prefrontal neurons that showed spatial representations similar to the concurrently reactivated hippocampal neurons were excited, whereas prefrontal neurons with unrelated representations were inhibited. Any potentially distracting activity inconsistent with the replayed information coming from the hippocampus would thus be suppressed, presumably optimizing awake memory function."



"A 2013 study published in the journal Frontiers in Human Neuroscience found that extraverts and introverts process experiences through the brain's "reward" centers quite differently. While extraverts often sense a feel-good rush of dopamine related to their surroundings, introverts tend to not experience such a shift. In fact, people who are naturally introverted do not process rewards from external factors as strongly as extraverts do."



"Researchers from the University of Michigan have revealed that cheese contains a chemical found in addictive drugs. Using the Yale Food Addiction Scale, designed to measure a person’s cravings, the study found that cheese is particularly moreish because it contains casein. The chemical, which is found in all dairy products, can trigger the brain’s opioid receptors, producing a feeling of euphoria linked to those of hard drug addiction."



"An extroverted brain's dopamine reward system responds more actively than an introverted brain's to rewards such as money, sex, social status, social affiliation and food, according to Scott Barry Kaufman, a psychologist and the scientific director of the Imagination Institute. (Dopamine is a neurotransmitter that helps regulate rewards and pleasures in the brain.) This may explain why an extrovert shows more excitement in a social setting than an introvert."



"The cause of psychopathy is different than the cause of sociopathy. It is believed that psychopathy is the largely the result of “nature” (genetics) while sociopathy is more likely the result of “nurture” (environment). Psychopathy is related to a physiological defect that results in the underdevelopment of the part of the brain responsible for impulse control and emotions. Sociopathy, on the other hand, is more likely the product of childhood trauma and physical/emotional abuse. Because sociopathy appears to be learned rather than innate, sociopaths are capable of empathy in certain limited circumstances but not in others, and with a few individuals but not others."



The researchers used data from two imaging techniques -- magnetic resonance imaging (MRI) and diffusion tensor imaging (DTI) -- to build three-dimensional maps of the structure of the brains of ten people.

"The MRI gave us the structure of their cortex -- the wrinkly surface of the brain -- and the DTI gave us an anatomical map of the underlying connections of the white matter in the brain," says Associate Professor Pearson. The team then analyzed these brain maps using the mathematical framework of Laplace Eingenmodes, or harmonic waves, which describe natural vibrations of a system where all parts move together at the same frequency.

"Our results show the shape of the brain matters, in the same way that the precise wooden shape of a Stradivarius violin matters if you want to produce an exquisite sound when the strings are vibrated," says Associate Professor Pearson.



"My advice: Don't assume that the people you're communicating with have context. Frame your message to focus on what matters to them. And provide the background they need to easily understand what you mean."



"Not surprisingly, offers that required low levels of effort were more likely to be accepted, but the team noticed something unusual: in the premotor cortex region of the brain, activity was higher rather than lower in those apparently 'apathetic' people who struggled to make decisions and accept the 'high-effort' offers. This suggests that inefficient processes within the brain rather than a lack of brain activity is behind our apathetic tendencies."



"If we understood something just one way, we would not understand it at all."
     -Marvin Minsky, cognitive scientist and founder of MIT's A.I. lab



In Gerd Gigerenzer's view this group includes much of the medical profession, most financial analysts and advisers, and, of course, many academics. The desire for ever greater complexity in the process of decision-making, driven by ever greater access to data, in practice produces what he calls risk-averse "defensive decision-making", or covering your backside. You don't do what your instinct and experience tells you is right: you find the data to support an inferior, but less personally risky choice.

Gigerenzer believes above all in the power of simple rules in the real, unfathomably complex world. "Probability theory is the best thing in a world where you can measure the risks exactly and the parameters are not too complicated. But for most problems it provides another illusion of certainty, and becomes part of the problem," he argues.



"Danish physicist Per Bak introduced self-organized criticality in a landmark 1987 paper — one of the most highly cited physics papers of the last 30 years. Bak began to see the stabilizing role of frequent smaller ["sand pile"] collapses wherever he looked. His 1996 book, “How Nature Works,” extended the concept beyond simple sand piles to other complex systems: earthquakes, financial markets, traffic jams, biological evolution, the distribution of galaxies in the universe — and the brain. Bak’s hypothesis implies that most of the time, the brain teeters on the edge of a phase transition, hovering between order and disorder."



Neurogenesis: Working Memory, Spatial Memory, Pattern Separation, Learning Flexibility
+Exercise, Enrichment
-Stress, Depression, Anxiety, Diabetes

"The dentate gyrus may also have a functional role in stress and depression. For instance, neurogenesis has been found to increase in response to chronic treatment with antidepressants. The physiological effects of stress, often characterized by release of glucocorticoids such as cortisol, as well as activation of the sympathetic division of the autonomic nervous system, have been shown to inhibit the process of neurogenesis in primates. Both endogenous and exogenous glucocorticoids are known to cause psychosis and depression, implying that neurogenesis in the dentate gyrus may play an important role in modulating symptoms of stress and depression."



"Evolutionarily, the creation of a maleness-femaleness mosaic within one brain makes sense, providing organisms with greater variability and therefore adaptability to changing environments. But another striking aspect of brain sexual differentiation that my colleagues and I have noted is that for each endpoint we examine, we find the magnitude of the sex difference to be constrained within the relatively low range of just one- to twofold. While this is still significantly greater than the extremely small variance within each sex, it is by no means colossal, as one might describe the difference between a male peacock’s tail and that of a peahen. It is as if something is both pushing the brains of the sexes apart and keeping them together at the same time."



"A new study published this week in the Proceedings of the National Academy of Sciences challenges that notion and puts forth a different theory: That that 'runners high' could be due to different substance called endocannabinoids [not endorphins]. Endocannabinoids can basically be thought of as the body's self-produced marijuana and, like cannabis, can impact a wide range of physiological processes, including appetite, pain, memory and mood.

In a study published in the journal Cell Metabolism, they compared normal mice with genetically engineered mice that lacked a leptin-sensitive protein called STAT3 that relays the leptin signal to release the reward chemical dopamine. The normal mice logged an average of six kilometers a day on a running wheel. But the genetically engineered mice ran nearly twice as much as the normal mice — 11 kilometers — each day."







"In the current issue of the journal Nature, a research team led by neuroscientists at UCLA and Caltech has rather haphazardly located a neuron that 'looks for all the world like a 'Jennifer Aniston' cell,' writes Charles Connor of Johns Hopkins University. Conner was not involved in the study.

These experiments were part of a study to localize the seizures in eight patients with epilepsy. The subjects consented to having electrodes implanted in their brains to record the signals of individual neurons. The researchers found that the neurons were selective (not firing for related subject matter) and invariant (firing for entirely different representations of the same person or thing).



"The 17th-century French mathematician and philosopher René Descartes famously introduced the notion of mind-body dualism, which holds that the world of the body is fundamentally separate from the world of the mind, or soul, although the two may interact. In the 19th century, the English biologist Thomas Huxley helped develop the theory of epiphenomenalism, the idea that physical events in the brain give rise to mental phenomena. On a World Science Festival panel, philosopher Colin McGinn of the University of Miami talked about panpsychism, the view that the universe is made of minds.

According to Susan Greenfield, a professor of pharmacology at Oxford University, the mind is made up of the physical connections between neurons. These connections evolve slowly and are influenced by our past experiences and therefore, everyone's brain is unique. But whereas the mind is rooted in the physical connections between neurons, Greenfield believes that consciousness is an emergent property of the brain, similar to the 'wetness' of water or the 'transparency' of glass, both of which are properties that are the result of -- that is, they emerge from -- the actions of individual molecules."



"Recently, researchers discovered a brain area that acts as a kind of on-off switch for the brain. When they electrically stimulated this region, called the claustrum, the patient became unconscious instantly. In fact, Koch and Francis Crick, the molecular biologist who famously helped discover the double-helix structure of DNA, had previously hypothesized that this region might integrate information across different parts of the brain, like the conductor of a symphony."



"The reason for this delay probably has to do with the undeveloped nature of a baby's brain, Kouider said. The second phase of activity that accompanies consciousness arises because the visual parts of the brain send information to the prefrontal cortex, which sits in the front of the skull. The prefrontal cortex directs and maintains attention and is crucial to consciousness. This part of the brain also develops slowest, going through major changes at about a year of age.

Babies' brains also lack myelin, a fatty substance that sheathes nerve fibers in the brain. Myelin acts as insulation, speeding up signals from one area of the brain to another. Before the brain is fully myelinated, neural impulses don't move as quickly from the visual brain regions at the back of the brain to the prefrontal cortex as the front."



» Wired: "Accept Defeat: The Neuroscience of Screwing Up"



» Nature: "Neuroscience vs. Philosophy: Taking aim at free will"



"People high in Machiavellianism are more likely to agree with statements like: 'It is wise to flatter important people' and 'The best way to handle people is to tell them what they want to hear'... In short, these new neuroimaging results suggest that when you’re mean to a jerk, his or her brain barely fires a synapse in response — it’s all that he expects from his fellow (wo)man. By contrast, if you show the jerk signs of fairness and cooperation, you’ll send his or her brain into a spin, as the manipulator works out the best way to take advantage of you. It’s a new and intriguing piece of evidence that we can add to the jigsaw puzzle of antisocial behavior."



"In 1986, the roundworm C. elegans, which has a mere 302 neurons, was the first, and to this date only, animal to have its complete connectome mapped (the researchers who did this won a Nobel Prize). Yet the brain of the worm, whose behaviors amount to smelling food and moving toward it, has never been successfully simulated. Human brains have about 100 billion neurons, so the enormousness of the task for a human brain is hard to overstate.

But some progress is being made — enough, anyway, so that the Obama administration signed off last year on a request by the National Institutes of Health for $4.5 billion to deliver a "comprehensive, mechanistic understanding of mental function" by 2025. Private foundations, like the Allen Institute for Brain Science and the Howard Hughes Medical Institute, have also announced major investments in basic brain research in recent years. And this summer, the blue-sky research arm of the United States intelligence agencies, Iarpa, distributed some $50 million in five-year grants to map the connectome in a cubic millimeter of mouse brain linked to learning behavior, record the corresponding neurons in live mouse brains and simulate the circuits in a computer. "

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