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Since the 1960s, advances in resuscitation had helped to revive thousands of people who might otherwise have died. About 10% or 20% of those people brought with them stories of near-death experiences in which they felt their souls or selves departing from their bodies

According to several international surveys and studies, one in 10 people claims to have had a near-death experience involving cardiac arrest, or a similar experience in circumstances where they may have come close to death. That’s roughly 800 million souls worldwide who may have dipped a toe in the afterlife.

In the 1970s, a small network of cardiologists, psychiatrists, medical sociologists and social psychologists in North America and Europe began investigating whether near-death experiences proved that dying is not the end of being, and that consciousness can exist independently of the brain. The field of near-death studies was born.

in 1975, an American medical student named Raymond Moody published a book called Life After Life.

Meanwhile, new technologies and techniques were helping doctors revive more and more people who, in earlier periods of history, would have almost certainly been permanently deceased.

“We are now at the point where we have both the tools and the means to scientifically answer the age-old question: What happens when we die?” wrote Sam Parnia, an accomplished resuscitation specialist and one of the world’s leading experts on near-death experiences, in 2006. Parnia himself was devising an international study to test whether patients could have conscious awareness even after they were found clinically dead.

Borjigin, together with several colleagues, took the first close look at the record of electrical activity in the brain of Patient One after she was taken off life support. What they discovered – in results reported for the first time last year – was almost entirely unexpected, and has the potential to rewrite our understanding of death.

“I believe what we found is only the tip of a vast iceberg,” Borjigin told me. “What’s still beneath the surface is a full account of how dying actually takes place. Because there’s something happening in there, in the brain, that makes no sense.”

Over the next 30 years, researchers collected thousands of case reports of people who had had near-death experiences

Moody was their most important spokesman; he eventually claimed to have had multiple past lives and built a “psychomanteum” in rural Alabama where people could attempt to summon the spirits of the dead by gazing into a dimly lit mirror.

near-death studies was already splitting into several schools of belief, whose tensions continue to this day. One influential camp was made up of spiritualists, some of them evangelical Christians, who were convinced that near-death experiences were genuine sojourns in the land of the dead and divine

It is no longer unheard of for people to be revived even six hours after being declared clinically dead. In 2011, Japanese doctors reported the case of a young woman who was found in a forest one morning after an overdose stopped her heart the previous night; using advanced technology to circulate blood and oxygen through her body, the doctors were able to revive her more than six hours later, and she was able to walk out of the hospital after three weeks of care

The second, and largest, faction of near-death researchers were the parapsychologists, those interested in phenomena that seemed to undermine the scientific orthodoxy that the mind could not exist independently of the brain. These researchers, who were by and large trained scientists following well established research methods, tended to believe that near-death experiences offered evidence that consciousness could persist after the death of the individua

Their aim was to find ways to test their theories of consciousness empirically, and to turn near-death studies into a legitimate scientific endeavour.

Finally, there emerged the smallest contingent of near-death researchers, who could be labelled the physicalists. These were scientists, many of whom studied the brain, who were committed to a strictly biological account of near-death experiences. Like dreams, the physicalists argued, near-death experiences might reveal psychological truths, but they did so through hallucinatory fictions that emerged from the workings of the body and the brain.

Between 1975, when Moody published Life After Life, and 1984, only 17 articles in the PubMed database of scientific publications mentioned near-death experiences. In the following decade, there were 62. In the most recent 10-year span, there were 221.

Today, there is a widespread sense throughout the community of near-death researchers that we are on the verge of great discoveries

“We really are in a crucial moment where we have to disentangle consciousness from responsiveness, and maybe question every state that we consider unconscious,”

“I think in 50 or 100 years time we will have discovered the entity that is consciousness,” he told me. “It will be taken for granted that it wasn’t produced by the brain, and it doesn’t die when you die.”

it is in large part because of a revolution in our ability to resuscitate people who have suffered cardiac arrest

In his book, Moody distilled the reports of 150 people who had had intense, life-altering experiences in the moments surrounding a cardiac arrest. Although the reports varied, he found that they often shared one or more common features or themes. The narrative arc of the most detailed of those reports – departing the body and travelling through a long tunnel, having an out-of-body experience, encountering spirits and a being of light, one’s whole life flashing before one’s eyes, and returning to the body from some outer limit – became so canonical that the art critic Robert Hughes could refer to it years later as “the familiar kitsch of near-death experience”.

Loss of oxygen to the brain and other organs generally follows within seconds or minutes, although the complete cessation of activity in the heart and brain – which is often called “flatlining” or, in the case of the latter, “brain death” – may not occur for many minutes or even hours.

That began to change in 1960, when the combination of mouth-to-mouth ventilation, chest compressions and external defibrillation known as cardiopulmonary resuscitation, or CPR, was formalised. Shortly thereafter, a massive campaign was launched to educate clinicians and the public on CPR’s basic techniques, and soon people were being revived in previously unthinkable, if still modest, numbers.

scientists learned that, even in its acute final stages, death is not a point, but a process. After cardiac arrest, blood and oxygen stop circulating through the body, cells begin to break down, and normal electrical activity in the brain gets disrupted. But the organs don’t fail irreversibly right away, and the brain doesn’t necessarily cease functioning altogether. There is often still the possibility of a return to life. In some cases, cell death can be stopped or significantly slowed, the heart can be restarted, and brain function can be restored. In other words, the process of death can be reversed.

In a medical setting, “clinical death” is said to occur at the moment the heart stops pumping blood, and the pulse stops. This is widely known as cardiac arrest

In 2019, a British woman named Audrey Schoeman who was caught in a snowstorm spent six hours in cardiac arrest before doctors brought her back to life with no evident brain damage.

That is a key tenet of the parapsychologists’ arguments: if there is consciousness without brain activity, then consciousness must dwell somewhere beyond the brain

Some of the parapsychologists speculate that it is a “non-local” force that pervades the universe, like electromagnetism. This force is received by the brain, but is not generated by it, the way a television receives a broadcast.

In order for this argument to hold, something else has to be true: near-death experiences have to happen during death, after the brain shuts down

To prove this, parapsychologists point to a number of rare but astounding cases known as “veridical” near-death experiences, in which patients seem to report details from the operating room that they might have known only if they had conscious awareness during the time that they were clinically dead.

At the very least, Parnia and his colleagues have written, such phenomena are “inexplicable through current neuroscientific models”. Unfortunately for the parapsychologists, however, none of the reports of post-death awareness holds up to strict scientific scrutiny. “There are many claims of this kind, but in my long decades of research into out-of-body and near-death experiences I never met any convincing evidence that this is true,”

In other cases, there’s not enough evidence to prove that the experiences reported by cardiac arrest survivors happened when their brains were shut down, as opposed to in the period before or after they supposedly “flatlined”. “So far, there is no sufficiently rigorous, convincing empirical evidence that people can observe their surroundings during a near-death experience,”

The parapsychologists tend to push back by arguing that even if each of the cases of veridical near-death experiences leaves room for scientific doubt, surely the accumulation of dozens of these reports must count for something. But that argument can be turned on its head: if there are so many genuine instances of consciousness surviving death, then why should it have so far proven impossible to catch one empirically?

The spiritualists and parapsychologists are right to insist that something deeply weird is happening to people when they die, but they are wrong to assume it is happening in the next life rather than this one. At least, that is the implication of what Jimo Borjigin found when she investigated the case of Patient One.

Given the levels of activity and connectivity in particular regions of her dying brain, Borjigin believes it’s likely that Patient One had a profound near-death experience with many of its major features: out-of-body sensations, visions of light, feelings of joy or serenity, and moral re-evaluations of one’s life. Of course,

“As she died, Patient One’s brain was functioning in a kind of hyperdrive,” Borjigin told me. For about two minutes after her oxygen was cut off, there was an intense synchronisation of her brain waves, a state associated with many cognitive functions, including heightened attention and memory. The synchronisation dampened for about 18 seconds, then intensified again for more than four minutes. It faded for a minute, then came back for a third time.

n those same periods of dying, different parts of Patient One’s brain were suddenly in close communication with each other. The most intense connections started immediately after her oxygen stopped, and lasted for nearly four minutes. There was another burst of connectivity more than five minutes and 20 seconds after she was taken off life support. In particular, areas of her brain associated with processing conscious experience – areas that are active when we move through the waking world, and when we have vivid dreams – were communicating with those involved in memory formation. So were parts of the brain associated with empathy. Even as she slipped irre

something that looked astonishingly like life was taking place over several minutes in Patient One’s brain.

Although a few earlier instances of brain waves had been reported in dying human brains, nothing as detailed and complex as what occurred in Patient One had ever been detected.

In the moments after Patient One was taken off oxygen, there was a surge of activity in her dying brain. Areas that had been nearly silent while she was on life support suddenly thrummed with high-frequency electrical signals called gamma waves. In particular, the parts of the brain that scientists consider a “hot zone” for consciousness became dramatically alive. In one section, the signals remained detectable for more than six minutes. In another, they were 11 to 12 times higher than they had been before Patient One’s ventilator was removed.

“The brain, contrary to everybody’s belief, is actually super active during cardiac arrest,” Borjigin said. Death may be far more alive than we ever thought possible.

“The brain is so resilient, the heart is so resilient, that it takes years of abuse to kill them,” she pointed out. “Why then, without oxygen, can a perfectly healthy person die within 30 minutes, irreversibly?”

Evidence is already emerging that even total brain death may someday be reversible. In 2019, scientists at Yale University harvested the brains of pigs that had been decapitated in a commercial slaughterhouse four hours earlier. Then they perfused the brains for six hours with a special cocktail of drugs and synthetic blood. Astoundingly, some of the cells in the brains began to show metabolic activity again, and some of the synapses even began firing.

If a brain can make crazy leaps across the cosmos and bring extra passengers along (like you when you listen to me), then in a metaphorical way, the brain is bigger than what's around it, wrote 19th century poet Emily Dickinson. The brain is wider than the sky,For, put them side by side,The one the other will includeWith ease, and you beside.

"The universe is not only queerer than we suppose," said the biologist J.B.S. Haldane, "but queerer than we can suppose." In Haldane's view, the universe is bigger than the brain. There are things we just can't know, or even conjure with the brains we've got.

If a brain can make crazy leaps across the cosmos and bring extra passengers along (like you when you listen to me), then in a metaphorical way, the brain is bigger than what's around it, wrote 19th century poet Emily Dickinson. The brain is wider than the sky,For, put them side by side,The one the other will includeWith ease, and you beside.

"The universe is not only queerer than we suppose," said the biologist J.B.S. Haldane, "but queerer than we can suppose." In Haldane's view, the universe is bigger than the brain. There are things we just can't know, or even conjure with the brains we've got.

"It's beyond our intellectual limits as a species. Put yourself into the position

"The universe is not only queerer than we suppose," said the biologist J.B.S. Haldane, "but queerer than we can suppose." In Haldane's view, the universe is bigger than the brain. There are things we just can't know, or even conjure with the brains we've got.

"The universe is not only queerer than we suppose," said the biologist J.B.S. Haldane, "but queerer than we can suppose." In Haldane's view, the universe is bigger than the brain. There are things we just can't know, or even conjure with the brains we've got.

"The universe is not only queerer than we suppose," said the biologist J.B.S. Haldane, "but queerer than we can suppose." In Haldane's view, the universe is bigger than the brain. There are things we just can't know, or even conjure with the brains we've got.

If a brain can make crazy leaps across the cosmos and bring extra passengers along (like you when you listen to me), then in a metaphorical way, the brain is bigger than what's around it, wrote 19th century poet Emily Dickinson. The brain is wider than the sky,For, put them side by side,The one the other will includeWith ease, and you beside.

"The universe is not only queerer than we suppose," said the biologist J.B.S. Haldane, "but queerer than we can suppose." In Haldane's view, the universe is bigger than the brain. There are things we just can't know, or even conjure with the brains we've got.

There are philosophers and scientists who say we will never understand the universe, we can't fathom the endless details or make good sense of the whole. We can try, but the universe is too big. The writer John Updike once explained the argument this way to reporter Jim Holt: "It's beyond our intellectual limits as a species. Put yourself into the position of a dog. A dog is responsive, shows intuition, looks at us with eyes behind which there is intelligence of a sort, and yet a dog must not understand most of the things it sees people doing. It must have no idea how they invented, say, the internal combustion engine. So maybe what we need to do is imagine that we're dogs and that there are realms that go beyond our understanding."

So does the universe get the crown?

Carl Sagan thought that we humans are good at finding patterns in nature, and if we know the rules, we can skip the details and understand the outline, the essence. It's not necessary for us to know everything. The problem is we don't know how many rules the cosmos has.

et the brain has its champions. "Consider the human brain," says physicist Sir Roger Penrose. "If you look at the entire physical cosmos, our brains are a tiny, tiny part of it. But they're the most perfectly organized part. Compared to the complexity of a brain, a galaxy is just an inert lump

my hunch is the universe will still outwit us, will still be "too wonderful" to be decoded, because we are, in the end, so much smaller than it is. And that's not a bad thing. To my mind, it's the search that matters, that sharpens us, gives us something noble to do.

Steven Weinberg famously said, "The effort to understand the universe is one of the very few things that lifts human life a little above the level of farce, and gives it some of the grace of tragedy."

The brain has bursts of growth and then periods of consolidation, when excess connections are pruned. The most notable bursts are in the first two or three years of life, during puberty, and also a final burst in young adulthood.

t is the most evolutionarily recent brain structure, dealing with more complex cognitive brain activities.

There are plenty of theories, of course, especially regarding why: increasingly complex social networks, a culture built around tool use and collaboration, the challenge of adapting to a mercurial and often harsh climate

Although these possibilities are fascinating, they are extremely difficult to test.

Although it makes up only 2 percent of body weight, the human brain consumes a whopping 20 percent of the body’s total energy at rest. In contrast, the chimpanzee brain needs only half that.

contrary to long-standing assumptions, larger mammalian brains do not always have more neurons, and the ones they do have are not always distributed in the same way.

The human brain has 86 billion neurons in all: 69 billion in the cerebellum, a dense lump at the back of the brain that helps orchestrate basic bodily functions and movement; 16 billion in the cerebral cortex, the brain’s thick corona and the seat of our most sophisticated mental talents, such as self-awareness, language, problem solving and abstract thought; and 1 billion in the brain stem and its extensions into the core of the brain

In contrast, the elephant brain, which is three times the size of our own, has 251 billion neurons in its cerebellum, which helps manage a giant, versatile trunk, and only 5.6 billion in its cortex

primates evolved a way to pack far more neurons into the cerebral cortex than other mammals did

The great apes are tiny compared to elephants and whales, yet their cortices are far denser: Orangutans and gorillas have 9 billion cortical neurons, and chimps have 6 billion. Of all the great apes, we have the largest brains, so we come out on top with our 16 billion neurons in the cortex.

“What kinds of mutations occurred, and what did they do? We’re starting to get answers and a deeper appreciation for just how complicated this process was.”

there was a strong evolutionary pressure to modify the human regulatory regions in a way that sapped energy from muscle and channeled it to the brain.

Accounting for body size and weight, the chimps and macaques were twice as strong as the humans. It’s not entirely clear why, but it is possible that our primate cousins get more power out of their muscles than we get out of ours because they feed their muscles more energy. “Compared to other primates, we lost muscle power in favor of sparing energy for our brains,” Bozek said. “It doesn’t mean that our muscles are inherently weaker. We might just have a different metabolism.

a pioneering experiment. Not only were they going to identify relevant genetic mutations from our brain’s evolutionary past, they were also going to weave those mutations into the genomes of lab mice and observe the consequences.

Silver and Wray introduced the chimpanzee copy of HARE5 into one group of mice and the human edition into a separate group. They then observed how the embryonic mice brains grew.

After nine days of development, mice embryos begin to form a cortex, the outer wrinkly layer of the brain associated with the most sophisticated mental talents. On day 10, the human version of HARE5 was much more active in the budding mice brains than the chimp copy, ultimately producing a brain that was 12 percent larger

“It wasn’t just a couple mutations and—bam!—you get a bigger brain. As we learn more about the changes between human and chimp brains, we realize there will be lots and lots of genes involved, each contributing a piece to that. The door is now open to get in there and really start understanding. The brain is modified in so many subtle and nonobvious ways.”

As recent research on whale and elephant brains makes clear, size is not everything, but it certainly counts for something. The reason we have so many more cortical neurons than our great-ape cousins is not that we have denser brains, but rather that we evolved ways to support brains that are large enough to accommodate all those extra cells.

There’s a danger, though, in becoming too enamored with our own big heads. Yes, a large brain packed with neurons is essential to what we consider high intelligence. But it’s not sufficient

No matter how large the human brain grew, or how much energy we lavished upon it, it would have been useless without the right body. Three particularly crucial adaptations worked in tandem with our burgeoning brain to dramatically increase our overall intelligence: bipedalism, which freed up our hands for tool making, fire building and hunting; manual dexterity surpassing that of any other animal; and a vocal tract that allowed us to speak and sing.

Human intelligence, then, cannot be traced to a single organ, no matter how large; it emerged from a serendipitous confluence of adaptations throughout the body. Despite our ongoing obsession with the size of our noggins, the fact is that our intelligence has always been so much bigger than our brain.

since the 18th century “when people were happy to spout off about what men and women’s brains were like – before you could even look at them. They came up with these nice ideas and metaphors that fitted the status quo and society, and gave rise to different education for men and women.”

she couldn’t find any beyond the negligible, and other research was also starting to question the very existence of such differences. For example, once any differences in brain size were accounted for, “well-known” sex differences in key structures disappeared.

Are there any significant differences based on sex alone? The answer, she says, is no.

“The idea of the male brain and the female brain suggests that each is a characteristically homogenous thing and that whoever has got a male brain, say, will have the same kind of aptitudes, preferences and personalities as everyone else with that ‘type’ of brain. We now know that is not the case.

‘Forget the male and female brain; it’s a distraction, it’s inaccurate.’ It’s possibly harmful, too, because it’s used as a hook to say, well, there’s no point girls doing science because they haven’t got a science brain, or boys shouldn’t be emotional or should want to lead.”

The next question was, what then is driving the differences in behaviour between girls and boys, men and women?

“that the brain is moulded from birth onwards and continues to be moulded through to the ‘cognitive cliff’ in old age when our grey cells start disappearing.

The rules will change how the brain works and how someone behaves.” The upshot of gendered rules? “The ‘gender gap’ becomes a self-fulfilling prophecy.”

The brain is also predictive and forward-thinking in a way we had never previously realised.

the brain is much more a function of experiences. If you learn a skill your brain will change, and it will carry on changing.”

The brain is a biological organ. Sex is a biological factor. But it is not the sole factor; it intersects with so many variables.”

Letting go of age-old certainties is frightening, concedes Rippon, who is both optimistic about the future, and fearful for it.

On the plus side, our plastic brains are good learners. All we need to do is change the life lessons.

One major breakthrough in recent years has been the realisation that, even in adulthood, our brains are continually being changed, not just by the education we receive, but also by the jobs we do, the hobbies we have, the sports we play.

Once we acknowledge that our brains are plastic and mouldable, then the power of gender stereotypes becomes evident.

Beliefs about sex differences (even if ill-founded) inform stereotypes, which commonly provide just two labels – girl or boy, female or male – which, in turn, historically carry with them huge amounts of “contents assured” information and save us having to judge each individual on their own merits

With input from exciting breakthroughs in neuroscience, the neat, binary distinctiveness of these labels is being challenged – we are coming to realise that nature is inextricably entangled with nurture.

The 21st century is not just challenging the old answers – it is challenging the question itself.

You have probably heard of this theory, in which the left and right halves of the brain are characterized, respectively, as logical versus intuitive, verbal versus perceptual, analytic versus synthetic, and so forth. The trouble is that none of these sweeping generalizations has stood up to careful scientific scrutiny. The dif­ferences between the left and right sides of the brain are nuanced, and simple, sweeping dichotomies do not in fact explain how the two sides function.

top and bottom portions of the brain have very different functions. This fact was first discovered in the context of visual perception, and it was supported in 1982 in a landmark report by National Medal of Science winner Mortimer Mishkin and Leslie G. Ungerleider, of the National Institute of Mental Health.

scientists trained monkeys to perform two tasks. In the first task, the monkeys had to learn to recognize which of two shapes concealed a bit of food.

These functions occur relatively close to where neural connec­tions deliver inputs from the eyes and ears—but processing doesn’t just stop there.

top parts of our frontal lobe can take into account the confluence of information about “what’s out there,” our emo­tional reactions to it, and our goals.

Four distinct cognitive modes emerge from how the top-brain and bottom-brain systems can interac

The two systems always work together. You use the top brain to decide to walk over to talk to your friend only after you know who she is (courtesy of the bottom brain). And after talking to her, you formulate another plan, to enter the date and time in your calendar, and then you need to monitor what hap­pens (again using the bottom brain) as you try to carry out this plan (a top-brain activity).

speak of differences in the degree to which a person relies on the top-brain and bottom-brain systems, we are speaking of differences in this second kind of utilization, in the kind of processing that’s not simply dictated by a given situation. In this sense, you can rely on one or the other brain system to a greater or lesser degree.

The degree to which you tend to use each system will affect your thoughts, feel­ings, and behavior in profound ways. The notion that each system can be more or less highly utilized, in this sense is the foundation of the Theory of Cognitive Modes. 

when faced with a change that has the potential to make us more likely to survive, some brains are able to adapt more easily than others.

Daniel Amen has studied over 63,000 brains using brain imaging to study blood flow and activity patterns.

One interesting conclusion of his studies is that a healthy brain is much better equipped to make positive changes and stick to them.

The discovery of brain plasticity has proven that you can help people change their brains almost immediately, by providing an environment to support learning

brain learns better when it is healthy, adopting a healthier lifestyle can help learners develop brains that are more receptive to change and new ideas.

Even a few drinks a week can reduce overall brain function and create areas of reduced brain function.

Prolonged exposure to high blood pressure not only restricts blood flow to the brain, but increase the risk of dementia, heart attack and stroke.

a physical pattern, in the form of neural connections, is formed in the brain. Every time we go over this pattern by revisiting this thought, we make the behavior stronger.

Brains with a high degree of new activity tend to stay that way. Brains that are slow to learn new things gradually lose some of their ability to change.

In our sleep-deprived world, the average adult is walking around in a brain-induced fog. The brain uses sleep to rebuild and reorganize. Sleep deprivation can result in lower brain performance and less ability to change.

Counter to previous beliefs, meditation has been shown to activate the cerebral cortex, which is the seat of conscious thought.

These past studies of exercise and neurogenesis understandably have focused on distance running. Lab rodents know how to run. But whether other forms of exercise likewise prompt increases in neurogenesis has been unknown and is an issue of increasing interest

new study, which was published this month in the Journal of Physiology, researchers at the University of Jyvaskyla in Finland and other institutions gathered a large group of adult male rats. The researchers injected the rats with a substance that marks new brain cells and then set groups of them to an array of different workouts, with one group remaining sedentary to serve as controls.

They found very different levels of neurogenesis, depending on how each animal had exercised. Those rats that had jogged on wheels showed robust levels of neurogenesis. Their hippocampal tissue teemed with new neurons, far more than in the brains of the sedentary animals. The greater the distance that a runner had covered during the experiment, the more new cells its brain now contained. There were far fewer new neurons in the brains of the animals that had completed high-intensity interval training. They showed somewhat higher amounts than in the sedentary animals but far less than in the distance runners. And the weight-training rats, although they were much stronger at the end of the experiment than they had been at the start, showed no discernible augmentation of neurogenesis. Their hippocampal tissue looked just like that of the animals that had not exercised at all.

“sustained aerobic exercise might be most beneficial for brain health also in humans.”

Just why distance running was so much more potent at promoting neurogenesis than the other workouts is not clear, although Dr. Nokia and her colleagues speculate that distance running stimulates the release of a particular substance in the brain known as brain-derived neurotrophic factor that is known to regulate neurogenesis. The more miles an animal runs, the more B.D.N.F. it produces. Weight training, on the other hand, while extremely beneficial for muscular health, has previously been shown to have little effect on the body’s levels of B.D.N.F.

As for high-intensity interval training, its potential brain benefits may be undercut by its very intensity, Dr. Nokia said. It is, by intent, much more physiologically draining and stressful than moderate running, and “stress tends to decrease adult hippocampal neurogenesis,” she said.

These results do not mean, however, that only running and similar moderate endurance workouts strengthen the brain, Dr. Nokia said. Those activities do seem to prompt the most neurogenesis in the hippocampus. But weight training and high-intensity intervals probably lead to different types of changes elsewhere in the brain. They might, for instance, encourage the creation of additional blood vessels or new connections between brain cells or between different parts of the brain.

The cerebrum has two halves, or hemispheres, that are further divided into four regions, or lobes. The frontal lobes, located behind the forehead, are involved with speech, thought, learning, emotion, and movement.

Behind them are the parietal lobes, which process sensory information such as touch, temperature, and pain.

At the rear of the brain are the occipital lobes, dealing with vision

Lastly, there are the temporal lobes, near the temples, which are involved with hearing and memory.

The second-largest part of the brain is the cerebellum, which sits beneath the back of the cerebrum.

diencephalon, located in the core of the brain. A complex of structures roughly the size of an apricot, its two major sections are the thalamus and hypothalamus

The brain is extremely sensitive and delicate, and so it requires maximum protection, which is provided by the hard bone of the skull and three tough membranes called meninges.

Want more proof that the brain is extraordinary? Look no further than the blood-brain barrier.

This led scientists to learn that the brain has an ingenious, protective layer. Called the blood-brain barrier, it’s made up of special, tightly bound cells that together function as a kind of semi-permeable gate throughout most of the organ. It keeps the brain environment safe and stable by preventing some toxins, pathogens, and other harmful substances from entering the brain through the bloodstream, while simultaneously allowing oxygen and vital nutrients to pass through.

One in five Americans suffers from some form of neurological damage, a wide-ranging list that includes stroke, epilepsy, and cerebral palsy, as well as dementia.

Alzheimer’s disease, which is characterized in part by a gradual progression of short-term memory loss, disorientation, and mood swings, is the most common cause of dementia. It is the sixth leading cause of death in the United States

50 million people suffer from Alzheimer’s or some form of dementia. While there are a handful of drugs available to mitigate Alzheimer’s symptoms, there is no cure.

Unfortunately, negative attitudes toward people who suffer from mental illness are widespread. The stigma attached to mental illness can create feelings of shame, embarrassment, and rejection, causing many people to suffer in silence.

In the United States, where anxiety disorders are the most common forms of mental illness, only about 40 percent of sufferers receive treatment. Anxiety disorders often stem from abnormalities in the brain’s hippocampus and prefrontal cortex.

Attention-deficit/hyperactivity disorder, or ADHD, is a mental health condition that also affects adults but is far more often diagnosed in children.

ADHD is characterized by hyperactivity and an inability to stay focused.

Depression is another common mental health condition. It is the leading cause of disability worldwide and is often accompanied by anxiety. Depression can be marked by an array of symptoms, including persistent sadness, irritability, and changes in appetite.

The good news is that in general, anxiety and depression are highly treatable through various medications—which help the brain use certain chemicals more efficiently—and through forms of therapy

The top brain comprises the entire parietal lobe and the top (and larger) portion of the frontal lobe. The bottom comprises the smaller remainder of the frontal lobe and all of the occipital and temporal lobes.

research reveals that the top-brain system uses information about the surrounding environment (in combination with other sorts of information, such as emotional reactions and the need for food or drink) to figure out which goals to try to achieve. It actively formulates plans, generates expectations about what should happen when a plan is executed and then, as the plan is being carried out, compares what is happening with what was expected, adjusting the plan accordingly.

The bottom-brain system organizes signals from the senses, simultaneously comparing what is being perceived with all the information previously stored in memory. It then uses the results of such comparisons to classify and interpret the object or event, allowing us to confer meaning on the world.

The top- and bottom-brain systems always work together, just as the hemispheres always do. Our brains are not engaged in some sort of constant cerebral tug of war

Although the top and bottom parts of the brain are always used during all of our waking lives, people do not rely on them to an equal degree. To extend the bicycle analogy, not everyone rides a bike the same way. Some may meander, others may race.

You can use the top-brain system to develop simple and straightforward plans, as required by a situation—or you have the option to use it to develop detailed and complex plans (which are not imposed by a situation).

Our theory predicts that people fit into one of four groups, based on their typical use of the two brain systems. Depending on the degree to which a person uses the top and bottom systems in optional ways, he or she will operate in one of four cognitive modes: Mover, Perceiver, Stimulator and Adaptor.

Mover mode results when the top- and bottom-brain systems are both highly utilized in optional ways. Oprah Winfrey

According to the theory, people who habitually rely on Mover mode are most comfortable in positions that allow them to plan, act and see the consequences of their actions. They are well suited to being leaders.

Perceiver mode results when the bottom-brain system is highly utilized in optional ways but the top is not. Think of the Dalai Lama or Emily Dickinson

People who habitually rely on Perceiver mode try to make sense in depth of what they perceive; they interpret their experiences, place them in context and try to understand the implications.

such people—including naturalists, pastors, novelists—typically lead lives away from the limelight. Those who rely on this mode often play a crucial role in a group; they can make sense of events and provide a bigger picture

Stimulator mode, which results when the top-brain system is highly utilized but the bottom is not. According to our theory, people who interact with the world in Stimulator mode often create and execute complex and detailed plans (using the top-brain system) but fail to register consistently and accurately the consequences of acting on those plans

they may not always note when enough is enough. Their actions can be disruptive, and they may not adjust their behavior appropriately.

Examples of people who illustrate Stimulator mode would include Tiger Woods

Adaptor mode, which results when neither the top- nor the bottom-brain system is highly utilized in optional ways. People who think in this mode are not caught up in initiating plans, nor are they fully focused on classifying and interpreting what they experience. Instead, they become absorbed by local events and the immediate requirements of the situation

They are responsive and action-oriented and tend to "go with the flow." Others see them as free-spirited and fun to be with.

those who typically operate in Adaptor mode can be valuable team members. In business, they often form the backbone of an organization, carrying out essential operations.

No one mode is "better" than the others. Each is more or less useful in different circumstances, and each contributes something useful to a team. Our theory leads us to expect that you can work with others most productively when you are aware not just of the strengths and weakness of their preferred modes but also of the strengths and weakness of your own preferred mode

The left cerebral hemisphere is to the “right-brained” poet or novelist as the hamstrings and quadriceps are to a competitive sprinter

Because the ability to understand and produce language is focused in the left side of the brain in almost everyone, caricaturing these creative types as using their right brain more than their left brain is silly.

visual-spatial abilities—localized to the right cerebral hemisphere—are skills that are absolutely critical for “left-brained” talents like science or engineering.

But much of our obsession with the brain’s left and right cerebral hemispheres may have started with studies of split brain patients in the ‘50s. During this time, people who suffered multiple seizures a day underwent intense surgery to treat their epilepsy.

To calm the electrical storms that ravaged these patients’ brains, the nerve fibers connecting the left and right hemispheres of the brain were cut. These fibers are collectively known as the corpus callosum

Once the corpus callosum is severed on the operating table, the new split brain patient appears astonishingly normal at first glance

But careful experiments reveal that this person is really two persons, two streams of consciousness in one body

only the left hemisphere can speak

The right hemisphere cannot speak, but it can point to words like “yes” or “no” to answer a question

Each hemisphere, it seems, maintains independent beliefs and personalities, challenging the notion that we are each an indivisible “self.”

We are all “brain-ambidextrous.”

But the impacts of learning on one of the most primal portions of the brain have been surprisingly underappreciated, both scientifically and outside the lab. Most of us pay little attention to our motor cortex, which controls how well we can move.

We like watching athletes in action, he said. But most of us make little effort to hone our motor skills in adulthood, and very few of us try to expand them by, for instance, learning a new sport. We could be short-changing our brains. Past neurological studies in people have shown that learning a new physical skill in adulthood, such as juggling, leads to increases in the volume of gray matter in parts of the brain related to movement control.

Even more compelling, a 2014 study with mice found that when the mice were introduced to a complicated type of running wheel, in which the rungs were irregularly spaced so that the animals had to learn a new, stutter-step type of running, their brains changed significantly. Learning to use these new wheels led to increased myelination of neurons in the animals’ motor cortexes. Myelination is the process by which parts of a brain cell are insulated, so that the messages between neurons can proceed more quickly and smoothly.

Scientists once believed that myelination in the brain occurs almost exclusively during infancy and childhood and then slows or halts altogether. But the animals running on the oddball wheels showed notable increases in the myelination of the neurons in their motor cortex even though they were adults.

In other words, learning the new skill had changed the inner workings of the adult animals’ motor cortexes; practicing a well-mastered one had not. “We don’t know” whether comparable changes occur within the brains of grown people who take up a new sport or physical skill, Dr. Krakauer said. But it seems likely, he said. “Motor skills are as cognitively challenging” in their way as traditional brainteasers such as crossword puzzles or brain-training games, he said. So adding a new sport to your repertory should have salutary effects on your brain, and also, unlike computer-based games, provide all the physical benefits of exercise.

these brain fibers grow

fibers connect your brain cells to one another at contact points called synapses.

Practice leads to stronger connections in the brain

brain fibers can only grow from existing brain fibers.

build on information that is already stored in the brain.

having a strong understanding of the foundational content in a given subject is essential

The larger your brain fibers grow, and the more brain cells they connect, the more information can be stored in your brain.

causes your dendrites to grow thicker and to coat themselves with a fatty layer.

With enough practice, these thickened brain fibers will eventually form double connections to one another.

The fatty coating on brain fibers also speeds up your brain’s ability to process information.

solidify that information or ability in your brain more permanently.

the brain grows fibers that relate to what you are practicing.

, but to also perform that skill yourself. This will help you truly learn it.

its general limit is five to seven items.

memory can be improved by taking proper care of your brain and body.

grouping items together before you try to memorize them.

a routine lack of sleep can have detrimental impacts on your health.

sleep deprivation can drastically diminish your brain’s ability to take in new information.

it is extremely important to get a full night’s rest within the first 30 hours of learning new knowledge.

“Bees manage surprisingly complex behavior with tiny brains,” making the evolution of bee brains an especially interesting subject.

Bees that only go through one generation each year have larger brains, relative to their body size, than bees with multiple generations a year.

A bee with a broad diet can fly into a field and drink the first nectar it finds. But a bee with a specialized diet may have to spot its preferred bloom, with its specific color and fragrance, among a whole field of similar flowers — a task that might require more brain.

Larger brains have also been linked to social behavior in primates and other mammals. But scientists found no connection between brain size and whether a bee lived in hives like honeybees or was a loner like our big-brained aster-eater.

“Highly social species have smaller brains because each individual is more like a cell in the body of the hive,”

Dr. Tibbetts said that even for vertebrates, whether bigger-brained animals are smarter is a topic of wide debate.

The effectiveness of this process is so great that human brain is able to accurately identify words and whole phrases from a noisy background. This power of analysis brings to minds the great similarity between the brain and powerful supercomputers.

Functional imaging of the brain revealed that activated brain parts are different between native and non-native speakers. The superior temporal gyrus is an important brain region involved in language learning. For a native speaker this part is responsible for automated processing of lexical retrieval and the build of phrase structure. In native speakers this zone is much more activated than in non-native ones.

infants begin their lives with a very flexible brain that allows them to acquire virtually any language they are exposed to. Moreover, they can learn a language words almost equally by listening or by visual coding. This brain plasticity is the motor drive of the children capability of “cracking the speech code” of a language. With time, this ability is dramatically decreased and adults find it harder to acquire a new language.

clearly demonstrated that there are anatomical brain differences between fast and slow learners of foreign languages. By analyzing a group of people having a homogenous language background, scientists found that differences in specific brain regions can predict the capacity of a person to learn a second language.

Until the last decade few studies compared the language acquisition in adults and children. Thanks to modern imaging and electroencephalography we are now able to address this question.

Language acquisition is a long-term process by which information are stored in the brain unconsciously making them appropriate to oral and written usage. In contrast, language learning is a conscious process of knowledge acquisition that needs supervision and control by the person.

Pregnancy, she explained, may help a woman’s brain specialize in “a mother’s ability to recognize the needs of her infant, to recognize social threats or to promote mother-infant bonding.”

Researchers wanted to see if the women’s brain changes affected anything related to mothering. They found that relevant brain regions in mothers showed more activity when women looked at photos of their own babies than with photos of other children.

During another period of roiling hormonal change — adolescence — gray matter decreases in several brain regions that are believed to provide fine-tuning for the social, emotional and cognitive territory of being a teenager.

evidence against the common myth of ‘mommy brain.’

Despite his injuries, Turner began giving first aid and pulled other soldiers to safety. As he worked, he was shot twice — one bullet breaking a bone in his arm. Yet Turner would say later that he felt almost no pain.

"Soldiers in the heat of the moment don't recognize the pain that's happening," Linden says. But once that moment is over, those same soldiers may feel a lot of pain from something minor, like a hypodermic needle, he says.

CIA interrogators used both tactics after Sept. 11, according to a Senate report released late last year.

One system determines the pain's location, intensity and characteristics: stabbing, aching, burning, etc.

there is a completely separate system for the emotional aspect of pain

positive emotions — like feeling calm and safe and connected to others — can minimize pain. But negative emotions tend to have the opposite effect. Torturers have exploited that aspect for centuries.

they want to accentuate pain during torture they can do this with humiliation [or] with an unpredictable schedule of delivering pain

Those things will make the emotional component of the pain experience stronger."

brain also determines the emotion we attach to each painful experience, Linden says. That's possible, he explains, because the brain uses two different systems to process pain information coming from our nerve endings.

One thing scientists are still trying to understand is precisely how the brain regulates the perception of pain

The team studied low-frequency brain waves in a part of the brain that responds to sensations in the hand,

Earlier research had shown that these rhythms increase when the brain is blocking sensory information from the hand.

reseasrchers monitored the brain waves of a dozen people who were asked to pay attention only to their hand or only to their foot. During the experiment the scientists delivered a light tap to each person's finger or toe.

ocused on their feet, low-frequency rhythms increased in the brain area that responds to hand sensations — because participants were asking their brains to ignore sensory input from the hand, and it's these low-frequency rhythms that do the blocking of such information.

low-frequency rhythms also increased in a different brain area — the region that ignores distractions, the team discovered.

The two areas became synchronized

"There's coordination between the front part of the brain, which is the executive control region of the brain, and the sensory part of the brain, which is filtering information from the environment," she says.

suggests that at least some people can teach their brains how to filter out things like chronic pain, perhaps through meditation

It found that people who practiced mindfulness meditation for eight weeks greatly improved their control of the brain rhythms that block out pain.

“At first, I was startled, and worried for myself, but it was so beautiful that I just stood in my slippers and stared.” It was like, “watching a slow-motion film.”

Before, he never rose beyond pre-Algebra.

Padgett is one of the few people on earth who can draw fractals accurately, freehand.

savant syndrome

There are two ways for it to occur, either through an injury that causes brain damage or through a disorder, such as autism.

It’s estimated that around 50% of those with savant syndrome are autistic.

“The most common ability to emerge is art, followed by music,” Treffert told The Guardian. “But I’ve had cases where brain damage makes people suddenly interested in dance, or in Pinball Wizard.”

During this time, the BrainEx system not only preserved brain cell structure and reduced cell death, but also restored some cellular activity.

For example, although scientists are a long way from being able to restore brain function in people with severe brain injuries, if some restoration of brain activity is possible, "then we would have to change our definition of brain death," Singhal told Live Science.

The work also could stimulate research on ways to promote brain recovery after loss of blood flow to the brain, such as during a heart attack.

invoked an old metaphor to explain why he isn’t convinced by the analysis: He compared it to establishing a theory of how weather works by pointing a video camera out the window for 7 hours.

Indeed, among neuroscientists, the new “comprehensive atlas” of the cerebral cortex is almost as controversial as a historical atlas of the Middle East. That’s because every word has a constellation of meanings and associations — and it’s hard for scientists to agree about how best to study them in the lab.

For this study, neuroscientist Jack Gallant and his team at the University of California, Berkeley played more than two hours’ worth of stories from the Moth Radio Hour for seven grad students and postdocs while measuring their cerebral blood flow using functional magnetic resonance imaging. Then, they linked the activity in some 50,000 pea-sized regions of the cortex to the “meaning” of the words being heard at that moment.

How, you might ask, did they establish the meaning of words? The neuroscientists pulled all the nouns and verbs from the podcasts. With a computer program, they then looked across millions of pages of text to see how often the words from the podcasts are used near 985 common words taken from Wikipedia’s List of 1,000 Basic Words. “Wolf,” for instance, would presumably be used more often in proximity to “dog” than to, say, “eggplant.” Using that data, the program assigned numbers that approximated the meaning of each individual word from the podcasts — and, with some fancy number crunching, they figured out what areas of the brain were activated when their research subjects heard words with certain meanings.

Everyone agrees that the research is innovative in its method. After all, linking up the meanings of thousands of words to the second-by-second brain activity in thousands of tiny brain regions is no mean feat. “That’s way more data than any human being can possibly think about,” said Gallant.

What they can’t agree on is what it means. “In this study, our goal was not to ask a specific question. Our goal was to map everything so that we can ask questions after that,” said Gallant. “One of the most frequent questions we get is, ‘What does it mean?’ If I gave you a globe, you wouldn’t ask what it means, you’d start using it for stuff. You can look for the smallest ocean or how long it will take to get to San Francisco.”

This “data-driven approach” still involves assumptions about how to break up language into different categories of meaning

“Of course it’s a very simplified version of how meaning is captured in our minds, but it seems to be a pretty good proxy,” she said.

hordes of unanswered questions: “We can map where your brain represents the meaning of a narrative text that is associated with family, but we don’t know why the brain is responding to family at that location. Is it the word ‘father’ itself? Is it your memories of your own father? Is it your own thinking about being a parent yourself?” He hopes that it’s just those types of questions that researchers will ask, using his brain map as a guide.