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Consciousness May Be the Product of Carefully Balanced Chaos ( 121

sciencehabit writes: The question of whether the human consciousness is subjective or objective is largely philosophical. But the line between consciousness and unconsciousness is a bit easier to measure. In a new study (abstract) of how anesthetic drugs affect the brain, researchers suggest that our experience of reality is the product of a delicate balance of connectivity between neurons—too much or too little and consciousness slips away. During wakeful consciousness, participants’ brains generated “a flurry of ever-changing activity”, and the fMRI showed a multitude of overlapping networks activating as the brain integrated its surroundings and generated a moment to moment “flow of consciousness.” After the propofol kicked in, brain networks had reduced connectivity and much less variability over time. The brain seemed to be stuck in a rut—using the same pathways over and over again.

New Clues To How the Brain Maps Time ( 79

An anonymous reader sends this excerpt from Quanta Magazine: Our brains have an extraordinary ability to monitor time. A driver can judge just how much time is left to run a yellow light; a dancer can keep a beat down to the millisecond. But exactly how the brain tracks time is still a mystery. Researchers have defined the brain areas involved in movement, memory, color vision and other functions, but not the ones that monitor time. Indeed, our neural timekeeper has proved so elusive that most scientists assume this mechanism is distributed throughout the brain, with different regions using different monitors to keep track of time according to their needs.

Over the last few years, a handful of researchers have compiled growing evidence that the same cells that monitor an individual's location in space also mark the passage of time. This suggests that two brain regions — the hippocampus and the entorhinal cortex, both famous for their role in memory and navigation — can also act as a sort of timer.


Weak Electrical Field Found To Carry Information Around the Brain ( 123

Zothecula writes: In a development that could lead to improved understanding of memory formation and epilepsy, scientists have discovered a new way information may be traveling throughout the brain. The team has identified slow-moving brainwaves it says could be carried only by the brain's gentle electrical field (abstract), a mechanism previously thought to be incapable of spreading neural signals altogether. "Although the electrical field is of low amplitude, the field excites and activates immediate neighbors, which, in turn, excite and activate immediate neighbors, and so on across the brain at a rate of about 0.1 meter per second."

How Procrastination Can Be Good For You ( 94 writes: Over 80 percent of college students are plagued by procrastination, requiring epic all-nighters to finish papers and prepare for tests. Roughly 20 percent of adults report being chronic procrastinators. But Adam Grant writes in the NY Times that while we think of procrastination as a curse for productivity, procrastination is really a virtue for creativity. According to Grant, our first ideas are usually our most conventional -- but when you procrastinate, you're more likely to let your mind wander, giving you a better chance of stumbling onto the unusual and spotting unexpected patterns. "When we finish a project, we file it away. But when it's in limbo, it stays active in our minds." Jihae Shin designed some experiments. She asked people to come up with new business ideas. Some were randomly assigned to start right away. Others were given five minutes to first play Minesweeper or Solitaire. Everyone submitted their ideas, and independent raters evaluated how original they were. The procrastinators' ideas were 28 percent more creative. When people played games before being told about the task, there was no increase in creativity. It was only when they first learned about the task and then put it off that they considered more novel ideas. It turned out that procrastination encouraged divergent thinking.

Even some monumental achievements are helped by procrastination. Grant says that according to those who knew him, Steve Jobs procrastinated constantly. Bill Clinton has been described as a "chronic procrastinator" who waits until the last minute to revise his speeches, and Frank Lloyd Wright spent almost a year procrastinating on a commission, to the point that his patron drove out and insisted that he produce a drawing on the spot. It became Fallingwater, Wright's masterpiece. Aaron Sorkin, the screenwriter behind Steve Jobs and The West Wing, is known to put off writing until the last minute. When Katie Couric asked him about it, he replied, "You call it procrastination, I call it thinking."


Brazil Cautions Women To Avoid Pregnancy Over Zika Virus Outbreak ( 102

iONiUM writes: According to an article at Discover, "Authorities in Brazil have recently issued an unusual and unprecedented announcement to women: don't get pregnant, at least not just yet. Amidst an intractable outbreak of the mosquito-borne Zika virus, public health authorities in Brazil are highly suspicious of an unusual surge of cases of microcephaly among newborn children." There were over 3,000 cases in 2015.

It's believed this virus is linked to shrinking newborns brain, and it is spreading. "Zika virus is transmitted by mosquitoes, and it was first detected in Uganda in the 1940s. After spreading through Africa and parts of Asia, it has made its way to Latin America. There is no known vaccine to prevent or medicine to treat the disease caused by the virus. Since May 2015, the Brazilian government estimates that some 1.5 million people have been infected with the virus." The CDC has published an article about it, and travel warnings are now being issued for pregnant women.


Human Brain Still Beats Computers At Finding Messages and Meaning Within Noise ( 64

szczys writes: One thing the human brain still does a lot better than computers is to recognize patterns within noise. That's why CAPTCHA uses distorted images to prove you're human, and random number generators are often inspected by visual representation. There is a technology that leverages this human knack for signal processing to make us part of the machine. The Hellschreiber is a communications device which has no idea whatsoever what the message actually is. It transfers a signal from one unit to the next, before being assembled into an image. A human looking at the image will see words, much like CAPTCHA. But even if the signal isn't perfect, our brains can often pick out the order within the madness, much like inspecting a PRNG for uniform distribution.

How Brain Architecture Leads To Abstract Thought ( 106

catchblue22 writes: UMass Amherst scientists have analyzed fMRI data to link brain architecture with consciousness and abstract thought. "We momentarily thought our research failed when we saw that each cognitive behavior showed activity through many network depths. Then we realized that cognition is far richer, it wasn't the simple hierarchy that everyone was looking for. So, we developed our geometrical 'slope' algorithm," said neuroscientist Hava Siegelmann (abstract). "With a slope identifier, behaviors could now be ordered by their relative depth activity with no human intervention or bias," she adds. They ranked slopes for all cognitive behaviors from the fMRI databases from negative to positive and found that they ordered from more tangible to highly abstract.

"'Deep learning is a computational system employing a multi-layered neural net...the brain's processing dynamic is far richer and less constrained because it has recurrent interconnection, sometimes called feedback loops.' Her lab is now creating a 'massively recurrent deep learning network,' she says, for a more brain-like and superior learning AI."


Rodent Neural Activity Has a Geometric Structure ( 27

TheAlexKnapp writes: In a recent paper (abstract), a team used techniques from computational topology to look at the neural activity in the rat hippocampus as it solved a maze. Mathematician Kevin Knudson explains the findings: "This is the first time geometric structure has been found intrinsically in neural data. Certainly such a structure is to be expected since the rat's place cells keep track of the geometry of the environment, but this result is confirmation that it can be detected using only the pattern of correlations among the neurons. And it suggests that such geometric structure is a property of the underlying place cell network and not a result of the spatial structure of the input cells."

The Brains of Men and Women Aren't Really That Different, Study Finds ( 163

sciencehabit writes: In the mid-19th century, researchers claimed they could tell the sex of an individual just by looking at their disembodied brain. But a new study (abstract) finds that human brains do not fit neatly into "male" and "female" categories. Indeed, all of our brains seem to share a patchwork of forms; some that are more common in males, others that are more common in females, and some that are common to both. The findings could change how scientists study the brain and even how society defines gender.

Neurons Can Be Changed From One Type To Another, Communication Paths Rewired ( 31

schwit1 writes: A newly published study from Harvard biologists [here's a link to the paywalled paper's summary] shows how neurons can be dramatically changed from one type into another from within the brain and how neighboring neurons recognize the reprogrammed cells as different and adapt by changing how they communicate with them. Building on earlier work in which they disproved neurobiology dogma by "reprogramming" neurons — turning one form of neuron into another — in the brains of living animals, Harvard Stem Cell Institute researchers have now shown that the networks of communication among reprogrammed neurons and their neighbors can also be changed, or "rewired."

Symbolic vs. Mnemonic Relational Operators: Is "GT" Greater Than ">"? 304

theodp writes: "Mnemonic operators," writes SAS's Rick Wicklin as he weighs the pros-and-cons of Symbolic Versus Mnemonic Logical Operators, "tend to appear in older languages like FORTRAN, whereas symbolic operators are common in more recent languages like C/C++, although some relatively recent scripting languages like Perl, PHP, and Windows PowerShell also support mnemonic operators. SAS software has supported both operators in the DATA step since the very earliest days, but the SAS/IML language, which is more mathematically oriented, supports only the symbolic operators. Functionally, the operators are equivalent, so which ones you use is largely a matter of personal preference. Since consistency and standards are essential when writing computer programming, which operators should you choose?"

The Neuroscientist Who Tested a Brain Implant On Himself ( 58

An anonymous reader writes: Our understanding of the brain has come a long way in the past thirty years, but most brain-related medical procedures remain incredibly complicated and dangerous. Neurologist Phil Kennedy has been working on brain-computer interfaces since the 1980s. He was most notably involved in letting a patient with "locked in" syndrome interact with the outside world through a brain-controlled computer cursor. But the FDA has gradually ramped up its safety demands, and in the past decade they've shut down Kennedy's research. So he did what any determined inventor would do: he went to a hospital in Belize and had surgeons there implant electrodes on his own brain so he could continue his research.

"After returning home to Duluth, Georgia, Kennedy began to toil largely alone in his speech lab, recording his neurons as he repeated 29 phonemes (such as e, eh, a, o, u, and consonants like ch and j) out loud, and then silently imagined saying them. ... Kennedy says his early findings are 'extremely encouraging.' He says he determined that different combinations of the 65 neurons he was recording from consistently fired every time he spoke certain sounds aloud, and also fired when he imagined speaking them—a relationship that is potentially key to developing a thought decoder for speech." Eventually, Kennedy had to have the implants removed, but he hopes the data he gathered will help push the FDA toward supporting this research once more.


You Can't Get Smarter, But You Can Slow How Fast You Get Dumber ( 82

An anonymous reader writes: An article at the NY Times summarizes the state of research on cognitive improvement. There are multiple industries — from big pharma to the makers of "brain-training" games — trying to convince you there are ways to become more intelligent. Unfortunately, scientific research doesn't really bear that out. There is, however, evidence you can provide short-term boosts, slow aging-related cognitive decline, and trick yourself into achieving better outcomes. Experiments show that simply telling a group of low-performing students that intelligence is malleable led to higher test scores. Researchers also found a use for mental exercises, but only in adults over the age of 60, a time at which some level of cognitive decline is common. Physical exercise seems to help fight that cognitive shrinkage as well. Oddly, different exercises fight it in different ways. As for drugs, there is some evidence that stimulants help with long-term memory, but that's about it. That's not to say they have no effect, just that their effect is more to make you feel smarter instead of actually being smarter. The article does point out one of the best ways to combat cognitive decline: maintain social engagement as you get older. "[P]eople with the highest level of social integration had less than half the decline in their cognitive function of the least socially active subjects."

Researchers Switch Neurons Off and On Using Noninvasive Ultrasound 37

Jason Koebler writes: Optogenetics, the ability to control neurons using bursts of light, has been one of the most promising breakthroughs in neurology of this decade. It's been a boon for researchers, but its invasive nature (the brain must usually be exposed) has held the technology back. Sreekanth Chalasani of the Salk Institute for Biological Studies described a new, noninvasive method of controlling neurons using ultrasound pulses in Nature Communications. For the first time ever, he was able to manipulate a genetically modified organism using a new technique called sonogenetics.

Finding Hope In Cryonics, Despite Glacial Progress 87

biobricks writes: The NY Times covers cryonics and destructive mind uploading, with some news on progress in brain preservation research. Quoting: "Dr. Fahy, a cryobiologist whose research focuses on organ banking, had provided the most encouraging signs that cryonics did preserve brain structure. In a 2009 experiment, his team showed that neurons in slices of rabbit brains immersed in the solution, chilled to cryogenic temperatures and then rewarmed, had responded to electrical stimulation. His method, he contended, preserved the connectome in those slices. But a complication prevented him from entering the prize competition: Brain tissue perfused with the cryoprotectant invariably becomes dehydrated, making it nearly impossible to see the details of the shrunken neurons and their connections under an electron microscope. ... He could fix the brain’s structure in place with chemicals first, just as Dr. Mikula was doing, buying time to perfuse the cryoprotectant more slowly to avoid dehydration. But he lacked the funds, he said, for a project that would have no practical business application for organ banking."

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