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Light Helps Injured Mice Walk Again
Mantrid42 writes "Researchers have been able to affect the brains of lab mice using light. Working in a new field called Optogenetics (optical stimulation plus genetic engineering), scientists injected lab mice with genes that can stimulate or inhibit neural activity based on the color of the light they're exposed to, and can be targeted to infect only on certain cell types. Additionally, another gene has been added to make neurons glow green when firing, allowing two-way communication between a brain and a machine."
yes in a way.. here's what i'm pondering. ounce for ounce, heat generated, how does the metabolism of a group of neurons stack up against computational elements taking the same space? Could you use the self orgainzing properties of neurons grown on a lab on a chip to connect in just the right way? Neurons are "better" at finding real world thresholds then there purely mathematical counterparts; i might say, more stable to me. Probably because they employ more then one method of signaling and collecting internally; chemical, electrical, inhibiting, unhibiting, etc. many states at once. perhaps if you could mass produce these and count on their self-assembly, you *could* make enough of it to be useful
i'm aware that computational simulation is often faster then taking a biological neuron _now_, but such a "computer" would be a wonderful platform for testing and learning about how neurons really *work* - it's like incredibly complex constraint system in programming (i mean, constraining one value to the value of something else)
CS majors know the time/space tradeoff, but they never get taught the 3rd, crucial, tradeoff of the set: comprehension!
This is the DNI we've been waiting for... The surgeon pops open your skull, injects some strategic locations with some gene altering viruses and installs some flashing lights. Now you can do two-way communication with a computer. What you experience depends on which cells were modified, and what program you're running. With sufficient funding for targeted research, we could see this technology in new kinds of: cochlear implants for the deaf, vision implants for the blind, artificial limb control and feeling for amputees.. and the continued improvement of those technologies will eventually lead to full sensation virtual reality immersion for anyone who can afford it. And we haven't even gotten into the gritty details of what we can learn about the brain using this technology.. reverse engineering is so much easier when you can poke as well as peek.
How we know is more important than what we know.
I mostly love this article, but it kinda glosses over how much more difficult it is to read out information out optically than it is to stimulate neurons with light. When you stimulate neurons you just need any ole photon, doesn't matter how many times it bounced around, or where it came from.. which is good because the brain isn't so much transparent, its kinda a milky haze. However, when you want to record optically from them you have to make an image of the neurons (unless you want all the neurons signals to get mixed together) and so you care about where all the photons came from. In order to take really effective pictures in the brain you need a fancy two photon microscope, and although some people are playing around with making tiny ones that one could potentially carry around on ones head.. they aren't really going to every be practically chronic implants for anyone, for many reasons.. but first of all you need to hook them up to a large, expensive infrared laser to make it work. That's not to say all this optical reading isn't really awesome, because scientists can make use of it to learn things about brains in more constrained situations.. i just wouldn't look to it to be the missing link in brain machine interfaces anytime soon.