Showing posts with label Neuroscience. Show all posts
Showing posts with label Neuroscience. Show all posts
Saturday, October 1, 2011
Researchers Reconstruct Visual experience from Brain Activity
Posted by Youtube user: gallantlabucb
Last week researchers from the University of California released a paper describing an experiment in which scientists managed to generate rough representations of visual stimuli by monitoring activity in the brain. This paper's release was also accompanied by the above video, which shows a comparison of the original images shown to participants in the test, along side the reconstructed versions generated by the computer.
While it's an impressive, even if imperfect, result. Chances are the reconstructed images seen in the video were not generated the way you think they were. Assuming of course that, like me, your mind is filled with images of people wearing funny devices on their heads, staring into some kind of strange optical device with their eyelids wired open like Clockwork Orange, or maybe even having their brains somehow jacked directly into computers all Johnny Mnemonic style -whoa-. No? Okay, so maybe it's just me, and I need to get out more and watch less sci-fi. Either way, Not surprisingly, that isn't the case.
In reality, these images were not collected directly from the subject's mind using any form of what you'd likely consider to be "mind-reading", in the traditional sci-fi sense. Instead, these images were generated by first collecting data from a subjects brain, via FMRI(Functional, Magnetic, Resonance, Imaging), and then asking a computer to reinterpret that data, and generate an image.
In order to accomplish this, the machine tasked with generating these images was first fed some 18 million 1 second YouTube clips -clips that were never shown to the participants in the experiment. Next, the subjects themselves each spent several hours lying inside an MRI machine and staring at a blue dot while being shown random YouTube clips; this allowed researchers to generate a map of basic visual activities within the brain during viewing using FMRI. Finally, those activity maps were then fed into the computer as well, and that computer was then was then asked to select from it's newly generated database of video clips, the images which best represented those being seen by the participants based solely on the activity shown on the scans.
In other words; the images you're seeing aren't actually images taken from "inside" any one's head like you might think. But rather, are a collection of images chosen by a computer and compiled together to represent what it determined to be the best visual representation of what the subject was seeing at the time, based on his or her brain activity.
So while this may not yet be the astonishing sc-fi milestone you may have thought it to be upon first reading the headlines surrounding it, it is an impressive feat. And though actually reading someone's thoughts and turning them into images is a very different thing than reinterperating direct visual stimulations of the brain, this could still potentialy be a major step towards achieving that goal. An accomplishment that would be invaluable to individuals who are otherwise unable to communicate.
-CAINE-
Source: dawn.com Paper Summary: sciencedirect.com
Saturday, September 17, 2011
How to Make Mouse Embryos Transparent with Pee & Anti-freeze
When I first found this story, I assumed the headline attached to it, "How to Make a Transparent Mouse with a Few Simple Ingredients", really meant, as is typically the case, something far less unusual than it sounded. Turns out, I was wrong. Scientists from Riken, a natural sciences research center in Japan, have actually developed a solution that really does make tissue transparent, dead tissue of course, but it was the transparent part that I was suspicious of. Oh, and did I mention that there's urine and anti-freeze involved? Well, sort of.
Using a simple recipe containing urea (see, I told ya), a cell membrane-softening detergent (Ooh, does that mean that Snuggle comes in "Flesh softening" now?) called Triton-X (oh, guess not) , and Glycerol, a component of antifreeze; researchers were able to create a solution called Scale (yes, the "l" is italicized on purpose, I don't know why). Other clearing agents similar to this already exist, but the degree to which they render tissues transparent varies, and they can often interfere with fluorescent tags inserted into the tissues for study. A two week soak in Scale, on the other hand, eliminates both these problems. And because this newest clearing agent allows researches to look as deep as they like into tissues, such as the brain, without interfering with their tagging agents, researchers hope that Scale will provide a simpler and more effective way to trace circuits of the brain in order to create better connectivity maps of the organ; delicate work, that is currently still being done by hand.
It should go without saying that a two week soak in urea, Glycerol, and flesh-softening detergent, would be, not only unpleasant, but not particularly conducive to allowing living tissue to remain that way. So for now, at least, Scale's applications are limited to dead tissues. But researchers do hope to develop a milder version that could be used on living tissue as well. Which could be great news for teenagers of the future, who could no longer be limited to tattoos, piercings, ridiculous clothing, and silly hair cuts, to piss-off their parents; and could instead, be getting things "transparented".
I can hear it now:
"TRANSPARENT IS BEAUTIFUL TOO!" and "I'm totally having my skin transparified to protest racism and animal cruelty. Organs are beautiful man, not food! And there is no hate, if we're all see-thru."
-CAINE-
Source: Discover Magazine VIA: GGB on tumblr
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