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Scientists Restore Walking After Spinal Cord Injury
Spinal cord damage blocks the routes that the brain uses to send messages to the nerve cells that control walking. Until now, doctors believed that the only way for injured patients to walk again was to re-grow the long nerve highways that link the brain and base of the spinal cord. For the first time, a UCLA study shows that the central nervous system can reorganize itself and follow new pathways to restore the cellular communication required for movement. The lead researcher said, "This pessimistic view [that severe injury to the spinal cord means permanent paralysis] has changed over my lifetime, and our findings add to a growing body of research showing that the nervous system can reorganize after injury."
I think your brain is compensating for a mismatched nerve map. Your sensations appear to be coming from the right place only because you know where they are supposed to be coming from.
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Ah, I see he cites that famous source, "a psychological study."
Here's something slightly more specific, with some references.
http://www.madsci.org/posts/archives/1997-03/858984531.Ns.r.html
They would try it, but broken spinal cord develops scar tissue that axons can't penetrate.
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It is basically random. It is recommended to touch and massage toddlers so they can develop better sense of their bodies.
Extreme Programming - Redundant Array of Inexpensive Developers
I know that one ! (My stepfather used to work in that field)
Spinal cord injuries may be repaired (even self heal) when you're harmed in the higher part of the spinal cord, near the brain. Counterintuitively, when it's cut near the bottom, it's nearly always definitive. Why ? Because the irrigation system is way more fragile in the lower part, and that's often where the problem is. When part of the spinal cord doesn't receive blood anymore, necrosis happens fast and then you can't do anything anymore.
Actually he is not far off base but most of the time it's not the feds, it's the local 5'o that overreacts. There was a case where a local family took some pictures of dad playing with his 3 and 5 year old daughters. He was tickling them doing that blowing on the belly thing.
The pictures where processed and since the pictures contained nude children the local police were called. That afternoon the children were taken by child custody and the parents were arrested for child molestation and production of child pornography.
After a few months the case was dismissed because the judge saw it for exactly what it was. It took another year for the parents to get their children back. Bullshit about being accused of child molestation, being proven innocent of the said charges had no bearing on the case. It took a court order and threatened jail time from the same judge to get that done.
So it's not always the feds. Sometimes it's just some local prosecutor with a bug up his ass to ruin a family. Ask the Duke lacrosse players if you don't believe me.
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Your brain compensates for flaws in your vision more than people think. People would be suprised how shitty their eyes really are and how much the brain makes up for it. I saw a show on the discovery channel. It illistrated how your vision, esp. behind your optic nerve, has holes in it. They demonstrated how much your brain just fills in that part by what it thinks should go there.
it was pretty amazing, and pretty scary. i had to drive the next day.
Supporting World Peace Through Nuclear Pacification
Key words there being is seen as - as seen by US. Obviously "seen as" is subjective and varies over time and among societies.
Yes, I agree completely, particularly since you're now saying that we're "deciding" rather than that's just "the way the system works".
That's actually a fairly well-studied question. In lower organisms like worms and flies, the nerve map is totally hard-wired. Every neuron is born in a specific location and extends its axons along specific pathways to pre-determined targets. In mammals it's a bit more complicated. There are millions of neurons and billions of precise connections between them. Looked at from a pragmatic point of view, there simply aren't enough genes in the genome to encode all of that specificity directly. So the body generally uses an approach to making its proper connections that you can divide into a few basic phases: getting there, finding your partners, and fighting for survival.
"Getting there" is all about pathfinding. Instead of individual neurons, groups of neurons have molecular identities in that they express cell surface molecules that probe the environment and react to it by either growing towards attractive molecules or away from repulsive molecules. Different groups of neurons can respond in opposite ways (or not respond at all) to the same exact signal, allowing combinatorial groups of signals to be used to guide the groups of neurons in their intricate paths through the brain and body.
The specificity of the "finding your partners" phase varies depending on the system you're looking at. For some groups of neurons it's almost a free-for-all within the group, while other groups of neurons follow very specific patterns. In the visual system, for instance, the neurons in the eye project into the brain in what's called a topographic map. That is, neurons that are near to each other in the eye form connections that are near each other in the brain, allowing the relative orientation of the signals from the eye to be directly mapped onto the correct region of the brain. This is done with 2-dimensional gradients of cues in the targets and of the receptors for those cues in the neurons that allow growing axons to hone in on just the level of the signal that is correct for them and find their correct general area. (See Ephrin and Eph signaling in the eye for more info.)
Once connections have been established, the "fight for survival" begins. Since it's not guaranteed that the connections that the neurons form will be the correct ones, the body has to have some way of keeping only the connections that are correct and eliminating unwanted ones. It often does this by strengthening connections that are properly formed and able to stimulate target neurons at the proper times and weakening those that don't work well by a process called Hebbian competition. This allows the map to be fine-tuned once the general arrangement has been worked out. There is usually a "critical period" during which the map can easily undergo dynamic rearrangement in response to experience. After this time, however, the ability of the brain to rewire in response to experience decreases drastically and the map is fairly fixed. For example, if someone loses function in one eye as a young child, their other eye will take over much more than half of the visual system space in the brain, while this does not happen to anywhere near the same extent if it happens later in life. This is also the reason that children with strabismus (unaligned eyes) have to be treated very early in life in order to ensure that their visual maps from each eye are aligned. If they aren't treated within the critical period, their vision can never be fixed.
Anyway, didn't mean to write such a long post, but there it is in case anyone's interested. I just wanted to add that the article title and summary are fairly misleading. I haven't read the article in full, but even from the abstract it's clear that the scientists did not use any new techniques to "restore walking" in these mice. It's been known for a while that mice have a high incidence and rate of spontaneous recovery after spinal cord injury in the lab. That is, they are often able to regain function of their hindlimbs despite the fact that the injured axons themselves do not grow back