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The visual system optimally maintains attention on relevant objects even as eye movements are made, shows a study by the German Primate Center.

Their study shows that the rhesus macaque's brain quickly and efficiently shifts attention with each eye-movement in a well-synchronized manner. Since humans and monkeys exhibit very similar eye-movements and visual function, these findings are likely to generalize to the human brain. These results may help understand disorders like schizophrenia, visual neglect and other attention deficit disorders.

Since different locations on the retina stimulate different visual neurons in the brain, this means that one set of visual neurons responds to the child before the eye-movement, while a different second set of neurons responds to the child after the eye-movement. Thus, to optimally maintain attention on the child, the brain has to enhance the responses of the first set of neurons right until the eye-movement begins and then switch to enhance the responses of the second set of neurons right around when the eye-movement ends.

paleontologists documented one of the most dramatic transitions in human evolution. We might call it the Brain Boom. Humans, chimps and bonobos split from their last common ancestor between 6 and 8 million years ago.

Starting around 3 million years ago, however, the hominin brain began a massive expansion. By the time our species, Homo sapiens, emerged about 200,000 years ago, the human brain had swelled from about 350 grams to more than 1,300 grams.

n that 3-million-year sprint, the human brain almost quadrupled the size its predecessors had attained over the previous 60 million years of primate evolution.

In 1928, Santiago Ramón y Cajal, the father of modern neuroscience, proclaimed that the brains of adult humans never make new neurons. “Once development was ended,” he wrote, “the founts of growth and regeneration ... dried up irrevocably. In the adult centers the nerve paths are something fixed, ended and immutable. Everything must die, nothing may be regenerated.”

For decades, scientists believed that neurogenesis—the creation of new neurons—whirs along nicely in the brains of embryos and infants, but grinds to a halt by adulthood. But from the 1980s onward, this dogma started to falter. Researchers showed that neurogenesis does occur in the brains of various adult animals, and eventually found signs of newly formed neurons in the adult human brain.

Finally, Gage and others say that several other lines of evidence suggest that adult neurogenesis in humans is real. For example, in 1998, he and his colleagues studied the brains of five cancer patients who had been injected with BrdU—a chemical that gets incorporated into newly created DNA. They found traces of this substance in the hippocampus, which they took as a sign that the cells there are dividing and creating new neurons.

So many large and small questions remain unanswered. How is information encoded and transferred from cell to cell or from network to network of cells?

Science found a genetic code but there is no brain-wide neural code; no electrical or chemical alphabet exists that can be recombined to say “red” or “fear” or “wink” or “run.” And no one knows whether information is encoded differently in various parts of the brain.

Single neurons, he said, are fairly well understood, as are small circuits of neurons.The question now on his mind, and that of many neuroscientists, is how larger groups, thousands of neurons, work together — whether to produce an action, like reaching for a cup, or to perceive something, like a flower.

In reality though, narcolepsy, cataplexy, and rapid eye movement (REM) sleep behavior disorder are all serious sleep-related illnesses. Researchers at the University of Tsukuba led by Professor Takeshi Sakurai have found neurons in the brain that link all three disorders and could provide a target for treatments.

In reality though, narcolepsy, cataplexy, and rapid eye movement (REM) sleep behavior disorder are all serious sleep-related illnesses. Researchers at the University of Tsukuba led by Professor Takeshi Sakurai have found neurons in the brain that link all three disorders and could provide a target for treatments.

Instead of being still during REM sleep, muscles move around, often going as far as to stand up and jump, yell, or punch.

primates have a remarkable ability to detect snakes, even in a chaotic visual environment.

first evidence of snake-selective neurons in the primate brain that I’m aware of,

recorded pulvinar neuronal activity via electrodes implanted into the brains of two adult macaques—one male, one female—as they were shown images of monkey faces, monkey hands, geometric shapes, and snakes. The brains of both monkeys—which were raised at a national monkey farm in Amami Island, Japan, and had no known encounters with snakes before the experiment—showed preferential activity of neurons in the medial and dorsolateral pulvinar to images of snakes, as compared with the other stimuli. Further, snakes elicited the fastest and strongest responses from these neurons.

General anesthesia has transformed surgery from a ghastly ordeal to a procedure in which the patient feels no pain.

“integrated-information theory,” which holds that consciousness relies on communication between different brain areas, and fades as that communication breaks down.

neural markers of consciousness—or more precisely, the loss of consciousness—a group led by Patrick Purdon

The more intelligent a person, the fewer connections there are between the neurons in his cerebral cortex.

Subsequently, the researchers associated the gathered data with each other and found out: the more intelligent a person, the fewer dendrites there are in their cerebral cortex.

For one, it had been previously ascertained that intelligent people tend to have larger brains. "The assumption has been that larger brains contain more neurons and, consequently, possess more computational power," says Erhan Genç. However, other studies had shown that -- despite their comparatively high number of neurons -- the brains of intelligent people demonstrated less neuronal activity during an IQ test than the brains of less intelligent individuals.

Even after one exposure to the composites, neurons that had previously fired exclusively in response to one picture—like that of Eastwood—significantly increased their firing rate  when exposed to the image with which it had been combined—in one case, by 230%, Fried and colleagues report today in the journal Neuron. The fact that an individual neuron can adapt its firing rate so quickly could help explain how large, dynamic neuronal networks form complicated memories of past events, Fried says.

Slow transit constipation (STC) is a common disease characterized by markedly delayed colonic transit time as a result of colonic motility dysfunction. It is well established that STC is mostly caused by disorders of relevant nerves, especially the enteric nervous system (ENS).

After 5 weeks of treatment, CES could enhance the colonic electromyogram (EMG) signal to promote colonic motility, thereby improving the colonic content emptying of STC beagles. HE staining and transmission electron microscopy confirmed that CES could regenerate ganglia and synaptic vesicles in the myenteric plexus.

Taken together, pulse train CES could induce the regeneration of myenteric plexus neurons, thereby promoting the colonic motility in STC beagles.

Genomic analyses of single human neurons—either from postmortem brains or those derived in culture—reveal a considerable degree of DNA copy number variation, according to a paper

likely that these genetic differences affect brain cell function, and they may even shape our personalities, academic abilities, and susceptibilities to neurological diseases.

There was a really long-standing hypothesis that given the huge diversity of cell types in the brain, there might be [genetic] mechanisms . . . to generate [the] diversity,” Hall explained.

Neurologically, how does our brain adapt itself to new technologies? Nicholas Carr: A couple of types of adaptations take place in your brain. One is a strengthening of the synaptical connections between the neurons involved in using that instrument, in using that tool. And basically these are chemical – neural chemical changes. So you know, cells in our brain communicate by transmitting electrical signals between them and those electrical signals are actually activated by the exchange of chemicals, neurotransmitters in our synapses. And so when you begin to use a tool, for instance, you have much stronger electrochemical signals being processed in those – through those synaptical connections. And then the second, and even more interesting adaptation is in actual physical changes,anatomical changes. Your neurons, you may grow new neurons that are then recruited into these circuits or your existing neurons may grow new synaptical terminals. And again, that also serves to strengthen the activity in those, in those particular pathways that are being used – new pathways. On the other hand, you know, the brain likes to be efficient and so even as its strengthening the pathways you’re exercising, it’s pulling – it’s weakening the connections in other ways between the cells that supported old ways of thinking or working or behaving, or whatever that you’re not exercising so much.

And it was only in around the year 800 or 900 that we saw the introduction of word spaces. And suddenly reading became, in a sense, easier and suddenly you had to arrival of silent reading, which changed the act of reading from just transcription of speech to something that every individual did on their own. And suddenly you had this whole deal of the silent solitary reader who was improving their mind, expanding their horizons, and so forth. And when Guttenberg invented the printing press around 1450, what that served to do was take this new very attentive, very deep form of reading, which had been limited to just, you know, monasteries and universities, and by making books much cheaper and much more available, spread that way of reading out to a much larger mass of audience. And so we saw, for the last 500 years or so, one of the central facts of culture was deep solitary reading.

What the book does as a technology is shield us from distraction. The only thinggoing on is the, you know, the progression of words and sentences across page after page and so suddenly we see this immersive kind of very attentive thinking, whether you are paying attention to a story or to an argument, or whatever. And what we know about the brain is the brain adapts to these types of tools.

Computers have entered the age when they are able to learn from their own mistakes, a development that is about to turn the digital world on its head.

Not only can it automate tasks that now require painstaking programming — for example, moving a robot’s arm smoothly and efficiently — but it can also sidestep and even tolerate errors, potentially making the term “computer crash” obsolete.

The new computing approach, already in use by some large technology companies, is based on the biological nervous system, specifically on how neurons react to stimuli and connect with other neurons to interpret information.

Most people have so-called flashbulb memories of where they were and what they were doing when something momentous happened: the assassination of President John F. Kennedy, say, or the explosion of the space shuttle Challenger.

But as clear and detailed as these memories feel, psychologists find they are surprisingly inaccurate.

Nader believes he may have an explanation for such quirks of memory. His ideas are unconventional within neuroscience, and they have caused researchers to reconsider some of their most basic assumptions about how memory works

the pace of improvement in technology would become a runaway phenomenon that would transform all aspects of human civilization.

the structure and functioning of the human brain is actually quite simple, a basic unit of cognition repeated millions of times. Therefore, creating an artificial brain will not require simulating the human brain at every level of detail. It will only require reverse engineering this basic repeating unit.

One afternoon in April 1929, a journalist from a Moscow newspaper turned up in Alexander Luria’s office with an unusual problem: He never forgot things.Dr. Luria, a neuropsychologist, proceeded to test the man, who later became known as subject S., by spouting long strings of numbers and words, foreign poems and scientific formulas, all of which S. recited back without fail. Decades later, S. still remembered the lists of numbers perfectly whenever Dr. Luria retested him.

“We’re inundated with so much information every day, and much of that information is turned into memories in the brain,” said Ronald Davis, a neurobiologist at the Scripps Research Institute in Jupiter, Fla. “We simply cannot deal with all of it.”

Researchers like Dr. Davis argue that forgetting is an active mechanism that the brain employs to clear out unnecessary pieces of information so we can retain new ones. Others have gone a step further, suggesting that forgetting is required for the mental flexibility inherent in creative thinking and imagination.

Theories of consciousness come from religion, from philosophy, from cognitive science, but not so much from evolutionary biology. Maybe that’s why so few theories have been able to tackle basic questions such as: What is the adaptive value of consciousness? When did it evolve and what animals have it?

The Attention Schema Theory (AST), developed over the past five years, may be able to answer those questions.

The theory suggests that consciousness arises as a solution to one of the most fundamental problems facing any nervous system: Too much information constantly flows in to be fully processed. The brain evolved increasingly sophisticated mechanisms for deeply processing a few select signals at the expense of others, and in the AST, consciousness is the ultimate result of that evolutionary sequence

Every culture ever studied has been found to make music, and among the oldest artistic objects known are slender flutes carved from mammoth bone some 43,000 years ago — 24,000 years before the cave paintings of Lascaux.

, many researchers had long assumed that the human brain must be equipped with some sort of music room, a distinctive piece of cortical architecture dedicated to detecting and interpreting the dulcet signals of song. Yet for years, scientists failed to find any clear evidence of a music-specific domain through conventional brain-scanning technology

devised a radical new approach to brain imaging that reveals what past studies had missed. By mathematically analyzing scans of the auditory cortex and grouping clusters of brain cells with similar activation patterns, the scientists have identified neural pathways that react almost exclusively to the sound of music — any music. It may be Bach, bluegrass, hip-hop, big band, sitar or Julie Andrews. A listener may relish the sampled genre or revile it. No matter. When a musical passage is played, a distinct set of neurons tucked inside a furrow of a listener’s auditory cortex will fire in response.Other sounds, by contrast — a dog barking, a car skidding, a toilet flushing — leave the musical circuits unmoved.

Judith, "barely clothed and fresh from the seduction and slaying of Holofernes, glows in her voluptuousness. Her hair is a dark sky between the golden branches of Assyrian trees, fertility symbols that represent her eroticism. This young, ecstatic, extravagantly made-up woman confronts the viewer through half-closed eyes in what appears to be a reverie of orgasmic rapture," writes Eric Kandel in his new book, The Age of Insight. Wait a minute. Writes who? Eric Kandel, the Nobel-winning neuroscientist who's spent most of his career fixated on the generously sized neurons of sea snails

Kandel goes on to speculate, in a bravura paragraph a few hundred pages later, on the exact neurochemical cognitive circuitry of the painting's viewer:

"At a base level, the aesthetics of the image's luminous gold surface, the soft rendering of the body, and the overall harmonious combination of colors could activate the pleasure circuits, triggering the release of dopamine. If Judith's smooth skin and exposed breast trigger the release of endorphins, oxytocin, and vasopressin, one might feel sexual excitement. The latent violence of Holofernes's decapitated head, as well as Judith's own sadistic gaze and upturned lip, could cause the release of norepinephrine, resulting in increased heart rate and blood pressure and triggering the fight-or-flight response. In contrast, the soft brushwork and repetitive, almost meditative, patterning may stimulate the release of serotonin. As the beholder takes in the image and its multifaceted emotional content, the release of acetylcholine to the hippocampus contributes to the storing of the image in the viewer's memory. What ultimately makes an image like Klimt's 'Judith' so irresistible and dynamic is its complexity, the way it activates a number of distinct and often conflicting emotional signals in the brain and combines them to produce a staggeringly complex and fascinating swirl of emotions."

Where do memories come from?

For quite some time the science of memories seemed focused on one pathway, but now there is new research indicating that this is only part of a larger story

There’s a kind of fashion about memory – like many mental models constructed for difficult concepts, the signs of the times inform how the current models approach the inquiry.