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asks and answers the question in every parent's mind, why are teenagers
reckless? It's due to how the teen brain interprets risks and rewards:
Recent studies in the neuroscientist B.J. Casey's lab at Cornell University suggest that adolescents aren't reckless because they underestimate risks, but because they overestimate rewards—or, rather, find rewards more rewarding than adults do. The reward centers of the adolescent brain are much more active than those of either children or adults. Think about the incomparable intensity of first love, the never-to-be-recaptured glory of the high-school basketball championship.
What teenagers want most of all are social rewards, especially the respect of their peers. In a recent study by the developmental psychologist Laurence Steinberg at Temple University, teenagers did a simulated high-risk driving task while they were lying in an fMRI brain-imaging machine. The reward system of their brains lighted up much more when they thought another teenager was watching what they did—and they took more risks.
Link (Image: Harry Campbell)
Researchers at Johns Hopkins University have discovered the neurochemical process that leads to memory formation, opening up the possibility of developing a pharmaceutical treatment for traumatic memories:
By looking at that process, Huganir and postdoctoral fellow Roger L. Clem discovered a “window of vulnerability” when unique receptor proteins are created. The proteins mediate signals traveling within the brain as painful memories are made. Because the proteins are unstable, they can be easily removed with drugs or behavior therapy during the window, ensuring the memory is eliminated.
Link via MArooned | Image: Columbia Pictures
Researchers at the Stanford School of Medicine attempted to measure the computational power of the combined synapses in the typical human brain. Lead researcher Stephen Smith wrote:
One synapse, by itself, is more like a microprocessor–with both memory-storage and information-processing elements–than a mere on/off switch. In fact, one synapse may contain on the order of 1,000 molecular-scale switches. A single human brain has more switches than all the computers and routers and Internet connections on Earth.
Link via Glenn Reynolds Photo by Flickr user dierk schaefer used under Creative Commons license
Stephanie Ortigue of Syracuse University conducted a study about the neurochemical reactions involved in falling in love. She found that different types of love are addressed by different parts of the brain.
For example, unconditional love, such as that between a mother and a child, is sparked by the common and different brain areas, including the middle of the brain. Passionate love is sparked by the reward part of the brain, and also associative cognitive brain areas that have higher-order cognitive functions, such as body image.
Ortigue also said (or at least the article about her study said) that falling in love takes one fifth of a second. That part of the article didn’t make a lot of sense to me, but perhaps Neatoramanauts more literate in biochemistry can explain.
Link via Ace of Spades HQ | Photo by Flickr user Garry Knight used under Creative Commons license
Paul Reber, professor of psychology at Northwestern University, responded to this question submitted to Scientific American:
The human brain consists of about one billion neurons. Each neuron forms about 1,000 connections to other neurons, amounting to more than a trillion connections. If each neuron could only help store a single memory, running out of space would be a problem. You might have only a few gigabytes of storage space, similar to the space in an iPod or a USB flash drive. Yet neurons combine so that each one helps with many memories at a time, exponentially increasing the brain’s memory storage capacity to something closer to around 2.5 petabytes (or a million gigabytes). For comparison, if your brain worked like a digital video recorder in a television, 2.5 petabytes would be enough to hold three million hours of TV shows. You would have to leave the TV running continuously for more than 300 years to use up all that storage.
Link | Image: US Department of Health and Human Services
The following is an article from Uncle John's Bathroom Reader Plunges into the Universe.
Cabinet-card portrait of Phineas Gage, shown holding the tamping iron
which injured him. From the Gage family of Texas collection.
Even if you're not a neurologist or a psychotherapist, you may
have heard of Phineas Gage. When a guy survives being impaled with a three-foot
iron rod in the skull, he tends to gain a certain notoriety. What makes
Gage's case interesting isn't the fact that he survived, it's
how he changed after his accident.
A
HOLE IN ONE
Phineas Gage considered himself a lucky man. At the age of 25, he had
a responsible, well-paid job as construction foreman for Rutland and Burlington
Railroad in Vermont. On September 13, 1848, as Gage was packing a load
of explosives into the ground, the charge exploded without warning. The
iron rod he was using to tamp the explosives into the earth flew into
the air with the force and speed of a rocket, hitting Phineas Gage directly
in the head. The 3'7" rod (109 cm), which weighed 13 pounds
(6 kg), entered his left cheek, careened straight through his skull and
brain, and emerged out of the top of his head like a yard-long bullet.
SURVIVOR
They loaded him into an ox cart and took him - still conscious - to
a hotel where some local doctors treated him. They never expected him
to live; he was bleeding horribly and blind in his left eye. Yet, Gage
was still able to walk, talk, even to work. He returned home just ten
weeks after his accident. However, Gage wasn't unscathed, not by
any means. The iron bar that had practically destroyed the front left
lobe of his brain had irrevocably changed his personality.
I FEEL LIKE A NEW MAN
A few months after the accident he was feeling well enough to return
to work, but his old boss wouldn't hire him back at the same position
because - even though Gage was almost back to normal physically, emotionally,
and mentally - he was a changed man. Before his accident he'd
been efficient, capable, kind, and polite; now he was foul-mouthed, rude,
and easily annoyed.
A FREAK, ALIVE OR DEAD
Gage never worked as foreman again. He drove coaches and cared for horses
in New Hampshire and in Chile. He exhibited himself (and the rod) as a
curiosity at P.T. Barnum's Museum in New York. All in all, he lived
13 years after his dreadful accident and died in 1860 after a series of
epileptic seizures.
Gage's skull (and the rod) are now on display at Harvard Medical
School, where they've been studied intensively over the years by
neuroscientists.
FIRST THE GOOD STUFF
Gage's abrupt personality changes clues neurologists in to the
fact that certain portions of the brain corresponded with personality
functions. And in fact, Gage's case made the very first brain tumor
removal operation possible in 1885. After studying what had happened to
Gage, the operating physician concluded that lesions or tumors located
in the frontal lobes of the brain didn't affect the brain's
ability to take in sense information. Nor did they have an impact on physical
movements or speech. However, such localized lesions or tumors did produce
highly characteristic and unusual personality changes like Gage's.
In 1894, that same surgeon removed a tumor from a patient's left
frontal lobe. The patient had complained his thinking was becoming increasingly
slow and dull. Seeing the similarities between this patient's mental
faculties and Gage's, the doctor successfully removed the tumor
that lay, just as he expected, in the left frontal lobes of the brain.
THE BIRTH OF THE LOBOTOMY
Gage's case put scientists on alert. Now they knew that certain
areas of the brain were responsible for certain functions. In 1890, after
a German scientist discovered that dogs were tamer and calmer after their
temporal lobe was removed, the attending doctor at a Swiss insane asylum
began to perform lobotomies on his patients - six in 1892. The patients
who had been hard to handle, restless, and even violent, seemed much calmer
after their surgeries. Lobotomies fell out of favor for a time, but were
revived in the 1930s. Suddenly, a sort of lobotomy frenzy overtook the
American psychiatric world.
THE ICE PICK TRICK
Along
came enterprising physician and neurologist Walter Freeman, a.k.a. the
Lobotomy King, who performed over 3,000 lobotomies from the 1930s to the
1960s. Impatient with the slowness of other brain surgery methods, Freeman
even created the superquick ice pick lobotomy. Instead of surgically opening
a hole in the patient's head, he put his patients under local anesthesia
and plunged an ice pick through the skull and into the brain. Once in,
Freeman would swing the ice pick swiftly back and forth, severing the
prefrontal lobe. An ice pick lobotomy took only a few minutes. The lobotomy-happy
Freeman would set up production lines at mental hospitals, operating on
as many as ten patients in a single afternoon.
EVERBODY'S DOING IT
Lobotomies were the psychiatric cure-all of choice in the 1940s and 1950s.
They were used not just on uncontrollable patients, but homosexuals, political
radicals, “troublesome" personalities, and other so-called
undesirables who veered from established norms. Even amateur surgeons
got into the act; they performed hundreds of lobotomies without first
performing psychiatric evaluations. Joseph Kennedy ordered a lobotomy
on his “difficult" daughter Rosemary in 1941 without consulting
anyone else in the family. Playwright Tennessee Williams was devastated
to find in 1937 that his schizophrenic sister Rose Williams had been lobotomized,
altering her personality utterly and permanently. The movie, Frances,
is a true story of fiercely independent actress Frances Farmer (as played
by Jessica Lange), who, after her lobotomy is a tragic picture of blandness.
LOBOTOMY TODAY?
Lobotomies are now outlawed in most countries, although they're
still occasionally performed to control violent behavior in Japan, Australia,
Sweden, and India.
Even though Phineas Gage needed that 1848 accident like a, well, like
a hole in the head, his case revolutionized brain surgery - in good
ways and bad.
__________
The
article above is reprinted with permission from Uncle
John's Bathroom Reader Plunges Into the Universe.
Since 1988, the Bathroom Reader Institute had published a series of popular
books containing irresistible bits of trivia and obscure
yet fascinating facts.
If you like Neatorama, you'll love the Bathroom
Reader Institute's books - go ahead and check 'em out!
What goes together better than neuroscience and LOLcats? It doesn’t matter, because they are together in this handy study guide, complete with a sparkly title and lots of sweet sugary cuteness along the synapses. Link -via Metafilter
A team of European computer researchers are building a computer that will simulate the way that neurons work. They hope that successful development could aid in nanotechnology and smart pharmaceutical control systems. Here’s how it works:
What distinguishes the current project is that it will make use of stable “cells” featuring a coating that forms spontaneously, similar to the walls of our own cells, and uses chemistry to accomplish the signal processing similar to that of our own neurons.[...]
The group’s approach hinges on two critical ideas.
First, individual “cells” are surrounded by a wall made up of so-called lipids that spontaneously encapsulate the liquid innards of the cell.
Recent work has shown that when two such lipid layers encounter each other as the cells come into contact, a protein can form a passage between them, allowing chemical signalling molecules to pass.
Second, the cells’ interiors will play host to what is known as a Belousov-Zhabotinsky or B-Z chemical reaction. Simply put, reactions of this type can be initiated by changing the concentration of the element bromine by a certain threshold amount.
Link via Popular Science | Image: US Department of Health and Human Services
The picture above is a 3D image of some of the neural connections in an owl-monkey’s brain. The Human Connectome Project of the US National Institutes for Health is currently engaged in a similar, but more ambitious project: to map every connection in the human brain. It’s like a circuit map for neurologists:
The complexity of the brain and a lack of adequate imaging technology have hampered past research on human brain connectivity. The brain is estimated to contain more than 100 billion neurons that form trillions of connections with each other. Neurons can connect across distant regions of the brain by extending long, slender projections called axons — but the trajectories that axons take within the human brain are almost entirely uncharted.[...]
The field of neuroscience emerged in the late 19th century, when scientists observed individual brain cells for the first time. Since then, researchers have made breathtaking progress in understanding the anatomy, cell biology, physiology and chemistry of the brain in both health and disease. Yet many fundamental questions remain unanswered, including how brain function translates into mental function and why brain function declines with age. Advances in neuroimaging, genomics, computational neuroscience and engineering have put us on the brink of another great era in neuroscience, when we can expect to make unprecedented discoveries regarding normal brain activity, disorders of the brain and our very sense of self.
Press Release and Article Link via GearFuse | Image: Van Wadeen
Princeton neuroscientist David Tank wanted to study individual neurons in a mouse’s hippocamus as it moves. But the movement of the mouse’s body prevented accurate readings. So he placed the mouse on a giant trackball and let it run through a virtual maze from the video game Quake 2 displayed on screens. Brandon Keim writes in Wired:
Studying individual neurons has been possible in cell cultures, but brains in a dish behave different than real, living brains. Tracking individual neurons in moving animals has been impossible.
“The neurons move back and forth while you’re trying to measure things,” said Tank. “So we developed a way to keep the head fixed in space, but still have mice perform behaviors that are usually studied in mice running through a maze.”
Tank’s team designed an apparatus in which a mouse, its head firmly held in a metal helmet, walks on the surface of a styrofoam ball. The ball is kept aloft by a jet of air, so that it functions like a multidirectional treadmill. Around it are sensors taken from optical computer mice, which read the ball’s movement as the mouse runs.
Those readings were the input for the researchers’ virtual reality software — a modified version of the open source Quake 2 videogame engine, tweaked to project an image on a screen surrounding the mouse. Tank called it “a mini-IMAX theater.”
Link via Popular Science
Neuroscientist Craig Bennett bought a salmon to test an fMRI machine and work out some protocols.
So, as the fish sat in the scanner, they showed it “a series of photographs depicting human individuals in social situations.” To maintain the rigor of the protocol (and perhaps because it was hilarious), the salmon, just like a human test subject, “was asked to determine what emotion the individual in the photo must have been experiencing.”
The salmon, as Bennett’s poster on the test dryly notes, “was not alive at the time of scanning.”
Those involved got a laugh out of the situation, until the scans came back and showed that activity was detected in different areas of the brain when the fish was “shown” the pictures. Remember, the fish was dead.
The result is completely nuts — but that’s actually exactly the point. Bennett, who is now a post-doc at the University of California, Santa Barbara, and his adviser, George Wolford, wrote up the work as a warning about the dangers of false positives in fMRI data. They wanted to call attention to ways the field could improve its statistical methods.
Which is not to say that scans aren’t a useful research tool, but that they must be carefully monitored to avoid false positive results. Link -via reddit
Ever notice when you walk into a room that you know something has changed and it takes a moment to realize what’s missing? Your eyes may know the answer before you do, as simple memory games have shown that your eyes focus on the correct answer before you are able to identify it.
By observing the hippocampus part of the brain, which is responsible for traditional memories, neuroscientists Deborah Hannula and Charan Ranganath noted that persons giving incorrect answers still had increased activity when their eyes observed the correct answer. The prefrontal cortex (PFC), which is responsible for decision making, mirrored the behavior of the hippocampus.
So your hippocampus may have made the connection that the napkin holder is missing, but your PFC must get involved for you to realize it. “The idea is that recollection may be a two-stage process,” Hannula says. “First you have retrieval of the memory, and then you have a conscious appreciation of what’s been retrieved.”
The study provides strong support for the idea that the hippocampus can process relational memories without a person being aware of it, says Boston University neuroscientist Howard Eichenbaum.
From the Upcoming 
ueue, submitted by OddNumber.
Why is it so uncomfortable to stand really close to a stranger? Sure, there are the potentially icky things. Sometimes an elevator car is so crowded that you can smell a fellow rider’s shampoo or chewing gum (or worse). But even when a stranger is perfectly groomed, it’s usually a bit revolting to be pressed against him in public. Why?
A team of scientists from Caltech put SM through a series of tests in which they asked her to indicate the position at which she became uncomfortable as another woman, a researcher, approached her. SM’s preferred personal distance was 1.1 ft. (0.34 m), about half the preferred distance (2 ft., or 0.64 m) of a group of comparison subjects. At 1 ft., you can easily discern whether someone showered after the gym — although in the lab experiment, the Caltech researchers made sure the experimenter was well-scrubbed and had just chewed gum before interacting with SM.
From the Upcoming ueue, submitted by Rossy21.
This CBC news story describes a brain surgery simulator that doctors in Halifax, Canada use for practice before cutting open real patients. It simulates not a generic human brain, but the brain of the specific patient:
First, patient data from functional magnetic resonance imaging (fMRI) is rendered into a 3-D, high-resolution model of an individual’s brain. After the model is loaded into the system, doctors can touch and manipulate tumors and other virtual objects on screens in real time using a physical instrument resembling a scalpel. The instrument has six degrees of freedom and re-creates the force-feedback of the real tool and the varying resistance of tissue in brain regions with differing toughness. Meanwhile, photo-realistic on-screen imagery shows the simulated surgery, including bleeding and pulsing gray matter.
Link via Popular Science
Japanese scientists at the ATR Computational Neuroscience Labs have successfully built a machine that can read your mind – or at least getting images straight from your brain:
A Japanese research team has revealed it had created a technology that could eventually display on a computer screen what people have on their minds, such as dreams.
Researchers at the ATR Computational Neuroscience Laboratories succeeded in processing and displaying images directly from the human brain, they said in a study unveiled ahead of publication in the US magazine Neuron.
While the team for now has managed to reproduce only simple images from the brain, they said the technology could eventually be used to figure out dreams and other secrets inside people’s minds.
Link | Article at Pink Tentacle – via Gizmodo
