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Brain Prosthesis Ready For Testing
jhouserizer writes "New Scientist is reporting that an artificial hippocampus is ready to undergo testing. The leader of the team of scientists is Theodore Berger of the University of Southern California in Los Angeles. They hope these artificial hippocampuses can replace damaged (stroke, Alzheimer's, etc.) portions of your brain. I wonder what portions of 'you' would be noticeably different to your family & friends? I wonder how long it will be before we can have HUDs, such as in this story by Cory Doctorow?"
It just has to say "I don't understand and "Where's my tea?".
A dyslexic man walks into a bra.
o/` Everybody wants prosthetic
foreheads on their real heads o/`
"Forgetting is the most beneficial process we possess," Williams says. It enables us to deal with painful situations without actually reliving them.
I am very interested in seeing how the brain would adapt to this. Would the brain always remember things or, in the case of trauma, learn to halt impulses before they reach the implanted area so that they are "forgotten"?
Where does the school board find them and why do they keep sending them to ME?
*taps prostetic arm*"I lost my arm in Nam.."
*taps prostetic leg*"I lost my leg in Korea.."
*taps head* "I lost my brain voting for Bush.."
I have a feeling this will be modded down.. heh.
Back in the day when I was studying to be a cognitive scientist (whatever that means), we did a lot of talking about what the nature of intelligence / mind actually is. There was a "strong anti-AI" camp which believed that Artificial Intelligence couldn't happen - even if you created a perfect simulation of a brain, you'd just be "simulating" intelligence, whatever that means.
So, we proposed an experiment. Let's say you took a guy who had completely lost function in a very small, localized area of the brain, and built a machine capable of reproducing its function entirely. You stuck it inside the guy's head, and he was magically fixed.
Now, make the area affected progressively larger - lets say, by replacing the whole hippocampus. Or the entire left hemisphere of the brain. Or, what the hell, the whole thing. At what point do you say that it's no longer a mind, and is "just" a machine?
So, that's the first thing I thought of when I saw this story. Once we can perfectly replicate the functionality of every last bit of the brain, do we just have a really nifty toy, or a genuine mind?
Unfortunately, that would violate the DMCA, and you know you haven't got a chance against the kind of lawyers God Himself can afford.
Karma: Chameleon (mostly affected when you come and go, you come and go)
The hippocampus integrates short-term memory into long-term. People who have had their hippocampus damaged (or removed) are unable to form any new long-term memories. They live incredibly interesting lives, because everyone they meet is a new person - every time they meet them. Why would you want to actually have yours replaced?
I told my wife that if I had my hippocampus removed, I'd get to sleep with a new woman every night, and not even be cheating on her! She didn't appreciate the comment so much, though....
steve
Oh, you're not stuck, you're just unable to let go of the onion rings.
You know, there's an old joke about a bunch of engineers being accidentally sent to hell, and being engineers, they spruced up the place considerably. Air conditioning, electricity, all the modern comforts. When God noticed the mistake, he went down and demanded that Satan return the engineers so they could go to heaven, as was their due. Satan refused and God threatened to sue. Satan's response was, "Sure, but where are you going to find a lawyer?"
I just want to take over the world...Why does that automatically make me EVIL?
You raise a very interesting point. Recording. With the chip designed to be external, there is definitely the ability to have your memories recorded onto chips. Or even more interesting, have people upload their memories to a computer, to where you can download them and store them in your head.
This could be a boon for training. Imagine being able to pull down a file from the net, jacking into a usb port, and after a while, being able to speak chinese. Or have an intimate knowlege of physics. Wow.
On the other hand, it would make the term "knowledge transfer" more insidious. Law enforcement would love this. Suspicious spouses too. Having an interface like this would end the last private place in your existence: your own head.
But this is only just come out of it's conceptual stage. It'll be interesting to see where the technology takes it.
These things are great. I just had one installed yesterday.
These things are great. I just had one installed yesterday.
These things are great. I just had one installed yesterday.
These things are great. I just had one installed yesterday.
These things are great. I just had one installed yesterday.
Who knows what changes in thought patterns might occur with completely fresh neurons in a brain?
No need to wonder; look at how "fresh neurons" behave in real life. In other words, look at newborn babies. The answer is "not much".
Neural weights only really have meaning in highly specific contexts. Even if you could "copy & paste" neurons in your brain, the new location would render the neurons effectively noise, having no coherent effect, and thus having effectively no effect at all.
Again, you can partially see this in the real world. We've watch people's brains adapt to losing vision and going to sound for their primary input, converting vision brain area to sound brain area in the process. It's not magical; the old vision stuff is effectively useless and completely re-purposed. Cognitive-level concepts are far, far, far higher then neural weights. So the old neurons are effectively full of garbage.
That's the reason this is so impressive to me. We've more-or-less decoded how the ear transmits sound to the brain, and have devices that can do this now, albiet not quite as well as real ears yet. We've started with ocular implants, though I don't know if that uses direct ocular nerve stimulation. This is because there are reasonably rational patterns that the sense data is transmitted in.
But once you're inside the brain, the nerve impulses have no objective meaning. "Thought transmission", if it is ever acheived by technology, won't be as simple as replaying neural impulses from one brain into another; there's no one-to-one correspondence between neurons, and certainly no corresponence to neural weights. (Odds are, we'd have to learn to use it, and it would 'just another' line of communication, not 'mind reading' as it was portrayed in past literature. Of course, if too much information is transmitted skilled "telepaths" might still get more information then the sender intended, just as reading body language can tell you more then the speaker intended.)
To acheive any success with an internal brain structure, understood or otherwise, is (IMHO, this is subjective of course) orders of magnitude more interesting then the ocular implants, which were pretty impressive themselves.
Again, I emphasize: This isn't magic. This is droll reality. Out of context, a neuron is nearly useless.
That's metaphysics; you are presupposing the existence of consciousness independent of a physical medium.
At present, there is no evidence to support (or refute) your hypothesis.
It's just as possible that consciousness is an epiphenomenon of chemical activity in a special configuration of neurons known as a "brain" - in much the same way that "Pac-Man" is an epiphenomenon of certain electrical impulses in special configuration of silicon known as a "Z80 CPU and EPROMs", or "P4 2.4GHz, hard drive, and MAME".
If the materialist viewpoint is the case, and the copy is destructive, then yes, one of me experiences death. And one of me experiences a lifetime before transfer to machine, followed by an odd transitional moment (which may not be "experienced" per se -- can a machine actually be said to be "running" code in the nanoseconds between clock cycles?), followed by life as a machine.
More interestingly, if the copying process is nondestructive, one of me experiences being the aforementioned weird transition from "running on meat" to "running on silicon", and the original experiences nothing worse than having some kind of funky scanner waved over me.
I'd like to run on silicon. fork() me a few times, plug my copies into space probes, and lob them off on random paths to star systems, and HLT me until there are enough photons bouncing off my solar panels to run my clock. It may take 500,000 years to go from star system to star system, but who cares? I cease to exist for half a million years at a time, but those are the boring parts of the trip anyways. Finally, I could see the galaxy on five Altarian dollars a day!
Anyway, when I first saw this headline I was thrilled at the prospect of scientists anywhere actually understanding any chunk of brain well enough to replace it (with a semiconductor, no less -- those must be some awesome I/O buffers on that ASIC -- what's brain voltage, uV? nV?).
Then I saw:
They just brute-forced it! This is remarkable achievement, but moreso from tech implementation standpoint than a brain understanding standpoint.
The point is, we don't have any clue at all about the uber-divx format that encodes human perception or memory. So the idea of storing it outside of the brain (or even viewing it, or cross-connecting 2 brains) is kinda silly at our level of understanding.
We just found a little chunk (the hippocampus) that is essential to storing memories and happens to get whacked often enough by stroke and such. Then we did an all-possible-input-combos test on this chunk (using rat brains, apparently), recorded the outputs, and burned the whole thing into a look-up table in a chip, and (this is the cool part) connected the chip to a real brain, bypassing a broken hippocampus chunk.
We just mimicked a relatively simple part of the brain with an exhaustive, brute-force approach that may not scale well to human hippocampi.
everything in moderation
No one understands how the hippocampus encodes information. So the team simply copied its behaviour. Slices of rat hippocampus were stimulated with electrical signals, millions of times over, until they could be sure which electrical input produces a corresponding output. Putting the information from various slices together gave the team a mathematical model of the entire hippocampus.
I suppose it's nice they were careful to avoid infringing on the brain's IP. (Or should that be The Brain's IP; I imagine he has a number of patents under his evil little belt.)
And the brethren went away edified.
...a math co-processor installed.
2+2? 5, of course. Dammit, I got an Intel.
if(!toilet_paper) roll.replace(new roll);
So how long before Hollywood forces them to add digital rights management so you can't steal the movie you just watched? I can see it now, you are only allowed to remember the movie for 3 days and then you have to go to the theatre again.
I do research on hippocampal functioning --- more specifically, I build neural network models of how the hippocampus supports memory for specific events. I was surprised by the statement in the new scientist article that "we know nothing about how the hippocampus encodes memories". There is actually quite a lot of consensus among researchers as to how the different subregions of the hippocampus support its overall function of storing and retrieving memories. If you want more information, a good place to start might be this paper that I wrote with my colleague Randy O'Reilly. Go to:
e mo ry/
http://www.princeton.edu/~psych/PsychSite/compm
then click on the first article under "Review Papers". You can follow the references to find other, relevant papers. Also, I should say that I am extremely skeptical that the prosthesis described in the New Scientist article will be able to substitue for an actual hippocampus. One of the key properties of the hippocampus (and the brain more generally) is that it *changes* as a function of experience --- every time you store a new memory in the hippocampus, it changes the strengths of synapses, which in turn changes the input-output function. So I can't see how it would be possible to replace the hippocampus using a simple, static lookup table. I may be missing something, but I think we are still a very long way from building an artificial hippocampus, and I think that we won't be successful in this endeavor unless we build in some knowledge about how the structure actually works...