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Scientists map schematic of brain's fibers
jake_the_blue_spruce writes "A simplified press release here and an abstract of the actual paper here details a Washington University study where they used MRI to track nerve fiber bundles from different identified areas of the brain. They made a 3D map of the resulting schematic. It's a lot like the bus-level view of a computer, with the various known brain areas as black boxes connected by fiber bundles. Cool. "Downside is that you have to request an image of it from the article. But I still think my brain looks like my Trash-80.
My condolences. There's still time to drop out and join an internet startup ;-^)
If you have bilateral temporal hemianopsia, I know right where the lesion is.
Almost always a lesion involving the chiasm, such as a pituitary adenoma or craniopharyngioma.
In fact, give me 100 patients with the same presenting visual disturbance, and the lesion will be in the same spot.
Unfortunately, this isn't quite accurate. Loss of vision in one eye might be caused by a central retinal artery embolus, a fracture involving the optic canal, an optic nerve glioma (intrinsic to the nerve), clinoidal segment aneurysm or meningioma (extrinsic compression), or perhaps a degenerative disease of the retina.
We know where the visual cortex is. We know how it receives data. We even know quite a bit on how he brain processes images, and what stages and levels of neurons do what processing. And it's the same in you, me, and Linus.
To a first approximation. Primary cortical areas are the most conserved, but higher order associative areas are poorly understood and difficult to map. I'm sure you are familiar with Penfield's experiments involving cortical stimulation during awake craniotomies for epilepsy. We still do not really understand these experiments. Moreover, there can be considerable variability between people of different sexes (more bilaterality of language representation in females), age (relative weakening of uncrossed pathways after childhood), and even among individuals. This is why we must do amytal tests and intraoperative cortical mapping in some cases. This is why it is probably a good idea to stimulate and record before making thalamotomy lesions, rather than simply depending upon a generic atlas
I will agree with the concept that interfacing directly with the cortex is probably technologically impossible for the reasons you state. However, getting data to the visual cortex, or any other part of the brain, for that matter, isn't that difficult.
A direct cortical interface is not that unrealistic. Although it would probably be impossible to implement an electrode grid with the same resolution of native visual cortex, it is reasonable to expect that we can achieve light, shapes, and shadows.
I'm sure you are also familiar with cochlear implants - electrodes essentially stimulating the cochlear nerve. At first, these patients hear a lot of distortion, but over time, their brain seems to tune itself to the input and they have serviceable hearing.
Also read Merznik's (sp?) work on cortical plasticity. Even in primary sensory or auditory cortex, the homotopic maps can be altered somewhat by changes in sensory inputs. Hence, representations of fingers change when they are sutured together, representations of tones change with auditory conditioning, and the relative sizes of barrel fields representing whiskers change with differential manipulation of the rodent's whiskers. I'm sure that this type of plasticity will be exploited in neurorestorative strategies.
I don't think the two are connected, but the tweaked mice raised my eyebrow too. I'm surprised it didn't get posted on /.
The CNN.COM version of the article ends with an ominous 'ethically questionable' blurb. B.S. says I! I've got my sleeve rolled up, and I'm waiting for the shot to come.
Mice are only good (in I.Q. research at least) for running through mazes and pushing on colored buttons. With this therapy/re-engineering, they got significantly better at their forte.
Imagine what an army of penguins could accomplish with the same genetic hack... And with gilded nerves... well...
-- What you do today will cost you a day of your life.
This modality - MRI - gives excellent spatial resolution. Unfortunately, it is not so good with temporal information, which can be at best on the order of a second, which is much slower than the brain processes information. In my lab we are using magnetoencepalography and related methods, in concert with MRI, to look at the temporal dynamics of the brain.
In other words, MRI gives a schematic of the brain, and fMRI tells you which parts get warm when doing certain tasks. We're trying to use MEG like a logic probe, to look at timing.
Our code base, both for signal processing and for visualization, is all developed on Debian GNU/Linux machines (both i386 and Alpha) and will all to be released under the GLP. It is also all being ported to SGIs and to large Linux clusters.
If you're interested in figuring out how the brain works and want to get a PhD or MS in CS at a really funky department while hacking Linux and playing with gonzo brain imaging data, don't be shy - get in touch.
Probably the best place to start reading about this sort of thing is Douglas R Hofstadter and Daniel C Dennett, "The Mind's I", but everything I've read by either author has been excellent.
I think the answer is this: *you* know you're thinking about your brain, at least if you stop to ask yourself, so clearly the information is available to brain processes should it be relevant. But it seems damn unlikely that it would look greatly different than other kinds of deep thought to any probe that only measured low-level activity like electrical patterns or chemical changes.
Put it this way: do you think your computer knows when you're recompiling a kernel?
--
Xenu loves you!
interesting, but unfortunately the paper fails to answer the most important questions for Slashdot readers :
Can this "human brain" thing run linux?
Can it be networked into a Beowulf?
I don't like to rain on people's parades, but as a student of cognitive science I consider it my job in this case. Don't believe the hype.
Beer recipe: free! #Source
Cold pints: $2 #Product
It would be really cool if someone requested the photo from the media affairs office and posted it somewhere . . . I would hate to think of what the
bror
I don't know about you, but I don't find skeletal structures to be particularly sexy...
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"'Is not a quine' is not a quine" is a quine.
"'Is not a quine' is not a quine" is a quine.
Quine "quine?
Interesting.. But why would thinking about itself have a different effect on the brain than thinking about anything else? For that matter, is thinking about thinking different than thinking about anything else? Is it 'meta-thinking'?
I think that I think, therefore I think that I am.. Uhhh... Maybe.
-- What you do today will cost you a day of your life.
Anyone ever read that?
It's a Walter Jon Williams cyberpunk book, akin to Count Zero, where people have their neural pathways 'treated' to improve their response/reflexes.. We might be seeing the first steps in that direction here.
Not too long from now, you won't have to practice that perfect golf swing for months. You'll just go to a walk-in clinic and have the responsible nerves anodized during lunch time, and be out on the green, kicking butt and taking names by early afternoon.
Talk about golden memories, too. Just have the neurons where the experience you want to remember are stored - gilded. It's like having gold-plated A/V contacts. You'd never forget anything again.
Too bad that doesn't work just from drinking Goldschlagger.
-- What you do today will cost you a day of your life.
Argh! Nooooo!
I've read it. Quite bizzare, even if interesting.
In Liberty, Rene