Posts Tagged ‘Neuroscience’
How Your Brain Will Betray You in a Court of Law [Crime]
Posted by: Gadget Boy in Gadget News on November 25th, 2009
I know it's science, which is ostensibly more objective than human intuition, but there's something unnerving about an MRI brain scan being admitted as evidence in a murder trial in Chicago, the first in the US.
True, here the fMRI is being used by the defense as a means to elude the death penalty, and only in the sentencing portion of the trial—not as a tool of conviction, as a dubious EEG scan was used to convict a woman of murder in India last year. Specifically, the fMRI scan is being submitted as evidence that the defendant Brian Dugan's brain is abnormal—psychopathic—and so he shouldn't be subject to the death penalty. The jury disagreed, but took 10 hours to reach the decision that the state should kill Dugan for his crime. Without the scan, Dugan's defense attorney says it would've take them an hour.
It's kind of hard to grasp, conceptually, looking inside somebody's brain, literally peering into their mind. It's something from fiction, something paranormal—mind readers and psychics—as a means of detection, a means of determining right and wrong, truth and lies. Brain scans to determine how much punishment your crime merits logically leads into brain scans that figure out whether or not you committed the crime, into scans that reveal every crime you have committed, a persistent and inescapable confessional. What secrets would your brain spill? [Science Mag via Wired]
Brain Scan Finds Man Was Not in a Coma—23 Years Later [Neuroscience]
Posted by: Gadget Boy in Gadget News on November 24th, 2009
Rom Houben has been trapped in a series of worst nightmares, including trying for 23 years to alert those around him that he was not in a coma. A new report suggests he's not alone in his experience.
In 1983, Belgian engineering student and martial arts enthusiast Houben, then 20, was in a car accident that was thought to have left him in a vegetative state. Doctors relied on the widely-used Glasgow Coma Scale, assessing his eyes, verbal, and motor responses. What they failed to notice was that Houben was actually conscious—but completely paralyzed.
"I screamed, but there was no one to hear," he says in an interview with the German magazine Der Spiegel. Three years ago, neurologist Steven Laureys used modern scanning techniques to discover that Houben's cerebral cortex was, in fact, functioning. (The doctor has only just now made Houben's story public.)
Houben, who communicates via a computer with a special keyboard activated with the slightest movement of his right hand, is now 46. He has spent more than half his life trapped in his own body, and says he only survived this excruciating existence by dreaming himself away. In the interview, this is what he typed:
I am called Rom. I am not dead. The nurses came, they patted me, they sometimes took my hand, and I heard them say "no hope." I meditated, I dreamed my life away—it was all I could do. I don't want to blame anyone—it wouldn't do any good. But I owe my life to my family. Everyone else gave up.
I studied what happened around me as if it were a tiny piece of world drama, the bizarre peculiarities of the other patients in the common room, the entry of the doctors into my room, the gossip of the nurses who were not embarrassed to speak about their boyfriends in front of "the extinct one." That made me an expert on relationships.
According to Laureys, Houben's case may be far more common than we'd like to think. The doctor, who leads the Coma Science Group and Department of Neurology at Liege University Hospital, says that while Houben's doctors were "not good," he's not sure better ones using this same coma scale would have detected brain activity either:
In Germany alone each year some 100,000 people suffer from severe traumatic brain injury. About 20,000 are followed by a coma of three weeks or longer. Some of them die, others regain health. But an estimated 3,000 to 5,000 people a year remain trapped in an intermediate stage—they go on living without ever coming back again.
In his paper, Laureys writes that in about 40 percent of "vegetative state" cases he has analyzed, current brain scanning techniques reveal signs of varying levels of consciousness. A case is being made, it seems, to stop relying on the Glasgow Coma Scale and start looking more closely at brain scanning images.
Optogenetics hold the key to future brain disease cures, still creep us out
Posted by: Gadget Boy in Gadget News on October 21st, 2009
Filed under: Science
Optogenetics hold the key to future brain disease cures, still creep us out originally appeared on Engadget on Wed, 21 Oct 2009 10:26:00 EST. Please see our terms for use of feeds.
Read | Permalink | Email this | CommentsMice run through Quake, Princeton neuroscientists scan their brains for traces of evil (video)
Posted by: Gadget Boy in Gadget News on October 15th, 2009
[Via Switched]
Filed under: Science
Mice run through Quake, Princeton neuroscientists scan their brains for traces of evil (video) originally appeared on Engadget on Thu, 15 Oct 2009 08:54:00 EST. Please see our terms for use of feeds.
Read | Permalink | Email this | CommentsReal Mouse Navigates Quake 2 Using a Trackball [Science]
Posted by: Gadget Boy in Gadget News on October 14th, 2009
Neuroscientists at Princeton created a new way to study the neurons of the classic mouse-in-a-maze: Strap it to a suspended ball and have it run through a virtual maze. That first virtual maze? Derived from a Quake 2 level.
Apparently it's difficult to control and study the neurons of a mouse when it's physically moving, and this method makes that easier. The ball is suspended on a jet of air, and the mouse is strapped in place with a collar on top of it (like a giant trackball, sort of). Given that I don't understand psychology at all, or even totally know what a neuron is, I'm going to go ahead and assume this is an elaborate ruse to get a mouse to play Quake 2. Well played, scientists. [Pop Sci]
Let’s hear it for inventors and makers
Posted by: Gadget Boy in Technology on August 25th, 2009
Galileo and his telescope are rightly celebrated. But will the inventors of integrated circuits, DNA sequencing and X-ray crystallography be remembered by future generations?
If it weren't for Google, which has transformed its logo into a telescopic doodle to mark the occasion, the 400th anniversary of the first public demonstration of Galileo's revolutionary telescope might have gone unnoticed. How strange that the public – and the media – can be captivated by revolutionary ideas in science, such as evolution and relativity, but fail to be impressed by the invention of new scientific instruments, which have arguably been far more important for human progress.
In centuries to come will we mark the anniversary of the invention of X-ray crystallography, DNA sequencing, magnetic resonance imaging, the silicon chip?
In his book Imagined Worlds, which is next month's Guardian Science Book Club title, Freeman Dyson notes that in the past 500 years there have been only seven concept-driven revolutions in science, which will forever be associated with the names Copernicus, Newton, Darwin, Maxwell, Freud, Einstein and Heisenberg. Over the same period, there have been 20 tool-driven revolutions, but none has captured the public imagination in quite the same way.
Dyson blames Thomas Kuhn and his famous book The Structure of Scientific Revolutions:
It misled a whole generation of students and historians of science into believing that all scientific revolutions are concept-driven. The concept-driven revolutions are the ones that attract the most attention and have the greatest impact on the public awareness of science, but in fact they are comparatively rare ... Two prime examples of tool-driven revolutions are the Galilean revolution resulting from the use of the telescope in astronomy, and the Crick-Watson revolution resulting from the use of X-ray diffraction to determine the structure of big molecules in biology.
Later in the book Dyson has fun speculating about future tool-driven revolutions, including "radioneurology" which would make telepathy possible. And he's perfectly serious:
There is no law of physics that declares such an observational tool to be impossible ... We need a technology that allows us to build and deploy large areas of small transmitters inside a living brain, just as integrated-circuit technology allows us to build large arrays of small transistors on a chip of silicon.
So let's hear it for the unsung heroes of human progress: the technicians and toolmakers. Galileo's telescope we remember, but what about Max von Laue (X-ray crystallography), Fred Sanger (DNA and protein sequencing), Jack Kilby and Robert Noyce (silicon chips)?
They deserve a Google doodle, all of them.
The quest to simulate a human brain
Posted by: Gadget Boy in Technology on July 22nd, 2009
Speaking at the TEDGlobal conference in Oxford, Henry Markram said that the model of the human brain he is building will fight disease and help us understand reality
Henry Markram is on a quest to find the holy grail of neuroscience, to understand the design of the neo-cortex, the newest part of the brain.
The neo-cortex, found only in mammals, developed to deal with parenthood and complex social interactions, Markram said. The number of neurons has increased by so much that the brain has actually outgrown the space in the human skull. It began to fold back on itself, leading to the grooved and wrinkled surface of our brains. The folds increased the surface area available for the billions of neurons in the human neo-cortex.
Markram is working to develop a model of the human brain because it is a key step to our understanding of the neo-cortex, and scientists cannot continue doing animal experimentation forever. It is key to understanding diseases and disorders, including Alzheimer's and autism.
99% of what we "see" is actually our brain inferring things about our surroundings, and he believes that a model of the brain will help us understand reality by understanding this fundamental internal reality.
Through intense study of the neo-cortex, not only the billions of neurons but just as importantly the rules of communications and connectivity, they have been able to build a three dimensional model of the neo-cortex. They have coded the rules that neurons use as a basis for communication with each other.
No two neurons are the same. They intersect in a complex network, creating what Markram described as the fabric of the brain. While the neurons are all different, the neurons fit together in a similar pattern in every human brain.
On a small scale, they now have the equations to simulate neurons and the electro-chemical reactions between them. It is a complex computer simulation. That in itself is a complex computer simulation. It is too difficult to simulate the connections between multiple neurons in silicon, Markram said.
To simulate a single neuron takes the computing power equivalent of a laptop. To build even a small model of the brain, they need a lot of laptops, about 10,000. But using an IBM supercomputer, "we can take the magic carpet for a ride".
They are now able to stimulate this simulated brain with images. If they show the brain a rose, what happens? "We can now follow the energy. We saw these ghostly electrical columns in the neo-cortex," Markram wrote.
They still have a lot more to do with these theories, but he said,
It is not impossible to build a brain, and if we succeed, in 10 years we will send a hologram to talk to you.
