what is the process by which reflex arcs are regenerated after spinal cord injury?
106953
Nerve injuries may be graded as follows from least severe to most severe:\n\nNeuropraxia: damage is minimal. Axons remain intact but conduction ceases due to segmental demyelination. This is transient with spontaneous recovery in days to weeks\n\nAxonometsis: Literally axonal seperation. Axons are severely damaged usually by traction or compression and the distal portions degenerate. The investing endoneural sheath remains intact however so recovery is likely although delayed\n\nNeurotmesis: Nerve completely divided and spontaneous recovery does not occur.
431392
the motor neurons in the peripheral nervous system.
364424
Most lizards have a characteristic called autotomy: they can lose a part of their tail (usually at times of danger from predators) as a defense mechanism and it grows back (however, the regenerated structure is not exactly the same as the original tail). They cannot grow other body parts back. \nThe ability to regenerate is present in most "lower" (as in having simpler organization) animals, but also in some vertebrates such as fish and amphibians. The acquisition or loss of this ability has to do with the evolutionary paths of each type of organism and thus your question does not have a simple answer. At a macromolecular/genetic level, we lack some genes (or they're inactivated) that are necessary for regeneration to occur.\nSome of these genes have been identified in animals that have regenerative ability:\nhttp://pda.physorg.com/lofi-news-genes-planarian-alvarado_3953.html
1147280
There is local injury to the ligaments and to the cartilege of the joints, which some researchers indicate may predispose to arthritis.  There is often noise.  Sometimes, in the presence of muscle spasm, it can trigger a "reset" of the "setpoint" of the alpha motor cells in the region, causing some relaxation, much like slapping the side of a malfunctioning TV will make it (sometimes) start working right.\n\nThis is about all that has been subjected to well controlled experimentation and demonstrated clearly.  The other claims made for spinal manipulation are not well researched (done with controls getting fake manipulations, and with numbers in the hundreds to thousands) and are not adequately proven.\n\nIf spinal manipulation had to get past the FDA, with the current data, it couldn't...  There isn't the safety and efficacy ( = research showing that it works) data out there that there is for, say, Lipitor or Fosamax or Lamictal or Prilosec or Zantac or....  frankly every drug it's legal to prescribe (or that once required prescription)...
1077350
Hats off to you. My condolences. My nephew also sustained a spinal cord injury. He is a quadraphelgic. He is 25 years old. He was diving and hit his head on a rock. He is otherwise healthy and adjusting well. Stem cell research and treatment is a great way to get going on finding a treatment and possible cure. If you want to get involved follow this link :http://www.paralysis.org/site/c.erJMJUOxFmH/b.1169107/k.BE3A/Home.htm.\nKeep up the good work. Bless you on your journey!
841920
If you have torn your ligaments, you probably have strained the neural tissue in the associated area. I would bet that you are having the ligaments repaired on the front-outer edge of your ankle. Following an ankle sprain/tear, you can damage the nerve that runs over the front of the ankle, and a nerve that is under the ankle bone on the inside of your foot. Either can cause a burning sensation esp. at night.\n\nIf the burning sensation is over the top of the foot, is the former, and if its the sole of the foot, is the latter.\n\nWhen you have your op. you will be in plaster for a few weeks. that should help settle it down.\n\nAfterwards, with post-op physio, you will get exercises, and probably neural stretches which will help.
695189
A voluntary reaction is one that when a sensory neuron feels something, say heat, it sends a signal to the spinal cord, then to the brain, the brain makes the conscious decision to remove your hand and send the signal to do so back to the hand muscles.\n\nA reflex reaction is one that takes the sensory neuron's signal, takes it to the spinal cord to an interneuron and directly back to the muscle where it retracts without the brain even needing to take the time consuming decision process.
714561
i am a chiropractor and specialize in spine related injuries. the disc acts as both a cushion and a spacer between each vertebrae. if a disc is bulging/herniated, that bulge can put pressure on the nerves exiting between each vertebra which causes a "pinched nerve." also if the disc is wearing out (getting thinner) you lose the space between the vertebra, which leaves less room for those nerves to exit--and again can pinch a nerve. the nerves in your cervical spine (neck) go all the way down your arm while the nerves in your lumbar spine (low back) form the sciatic nerve which runs all the way down your leg. if any of these are "pinched" they can cause pain, numbess, tingling, weakness wherever these nerves go (down arms/legs).\n\nas a chiropractor i see this type of scenario on a daily basis. for those who have degenerative disc disease, disc herniation, disc bulging, etc.--normal chiropractic care can usually help with those problems. but there are also many people out there that have had this problem for many years and can't find relief with anything they try--including chiropractic. \n\nbut now there is a treatment that is perfect for your situation and the best part is: it's non-surgical and non-invasive. if you haven't heard of it yet it is called spinal decompression. this type of treatment focuses on disc injuries and the problems they cause. i use the DRX9000 spinal decompression system in my office and it works wonders for people with these types of injuries (approx. 90% successful). the DRX9000 is fda approved and is the best decompression system available (there are cheap knock-offs that don't give the same results). \n\nmy recommendation would be to see a chiro, especially if you've never tried it before-just to see what they have to say. also do some research on this treatment and then contact someone (usually a chiro) who uses it in their office. i would just google "DRX9000" to find info on it and doctors in your area who may have it. this treament is able to encourage the disc to go back to it's normal orientation and also rebuild its height--which then takes the pressure off whatever nerve it is compressing. pain meds, cortisone shots, epidurals won't do anything to solve the problem--all they do is cover it up and they become less and less effective over time. surgery AT BEST is 50% successful and usually doesn't solve the problem since most people need another surgery 5-10 years down the road for the same issue. it's typically a viscious cycle. remember: surgery is always an option, so try something prior to surgery to see if you can avoid it--cause once you do the surgery there is no going back.\n\nthis treatment is extremely effective for degenerative disc disease, disc bulging, herniation, etc. and also sciatica type of cases, especially if you haven't had surgery yet. i've had many patients who were scheduled for surgery, tried this treatment as a last resort, and then ended up cancelling their surgery altogether after treatment was completed. it really does work and that's what my recommendation would be for you. good luck and hopefully this gives insight to others experiencing similar problems--there is a solution!!!
988969
Get a clue, your body is trying to tell you something. You need to see your doctor.\n\nTreatment may include:putting ice packs on the injured area for 20 to 30 minutes every 3 to 4 hours for 2 to 3 days or until the pain goes away, taking anti-inflammatory medications prescribed by your doctor and doing rehabilitation exercises to help you return to your activity.\n\nWhile you are recovering from your injury, you will need to change your activity to one that does not make your condition worse. You may need to swim instead of running.
375099
Spinal\n\n\n\nErection is basically a spinal reflex that can be initiated by recruitment of penile afferents, but also by visual, olfactory, and imaginary stimuli. The reflex involves both autonomic and somatic efferents and is modulated by supraspinal influences. Several central transmitters involved in the erectile control have been identified. Dopamine, acetylcholine, nitric oxide (NO), and peptides, such as oxytocin and adrenocorticotropic/alpha-melanocyte-stimulating hormone, seem to have a facilitatory role, whereas serotonin may be either facilitatory or inhibitory, and enkephalins are inhibitory.
406206
I answered that same question yesterday:\nThe impulse reaches the terminal end of the motor neuron and breaks open the synaptic vesicles, releasing the neurotransmitter acetylcholine into the synaptic cleft.\nACh then binds to receptor molecules in the motor end plate of the muscle fiber.\nThe action potential is started in sarcolemma and passes along the membrane until it reaches the sarcoplasmic reticulum releasing calcium. Calcium diffuses in sarcoplasm and binds to the troponin in the thin filaments.\nThe binding sites on the actin molecules are freed, allowing\nthe heads of myosin (thick filaments) to attach on the binding sites forming the cross-bridges connections.\nThe cross-bridges shift their angle causing the thin filaments to slide over the thick filaments; this produces the contraction.\nATP is needed for the last step. ATP is bound to myosin; calcium activates ATP breakdown into ADP and phosphate.\nPart of the energy produced is used to move bridges, the other part is released as heat, increasing the body temperature.\nMore ATP breaks the bond between thick and thin filaments in the cross bridge; calcium returns to thesarcoplasmic reticulum and the thin filaments return to their original position, closing off the binding site to cross bridges and causing the muscle to relaxe.
327965
Nerve damage! if your nerves got severed and were reattached, you need to keep doing the Physical therapy you did at the sessions. It has to be a constant thing.If it is painful, remember that whilst the nerves are still healing , it will hurt. If this was a recent accident please DO NOT rest your hand for extensive periods of time thinking that your hand will heal and be better, it is the complete opposite and your hand will become immobile for sure from not moving.Compare it to an ungreased bycicle chain, you hear it creaking,squeaking because it wasn't greased and it doesn't want to go anywhere.That is why you want to keep your fingers and hand moving as much as you can. Get a remote and do finger pressing excersising, from the top button all the way down. Do this every half hour while you are awake. Are you wearing a hand brace? Something that keeps your hand tight, it's an elastic thing.Try not to wear it too much.\nOpen and close your fist as much as you can, same as the finger excersices. If you have no open wounds on your hands, try using a few drops of pepermint oil with a base of avocado oil (Bath and body works) and rub it on your hands, it should really help with your numbness as the pepermint oil gets your nerves reacting, and it penetrates.\nIf you can't move the fingers willingly, move each finger up and down and flex them with the help of your other hand and fingers. Don't let the hand get lazy.Keep it moving.Nerves will regenerate and they will pick up where they left off if you keep them busy and functioning. Keep the idea of the ungreased bycicle chain in your head and move your hand and use it so it doesn't stop working.Don't become unmotivated or lazy. Do things as normal. Even if your hand is in pain, do things, it's because your nerves are trying to repair themselves that they hurt and it feels like shooting pain.So the more you move, the better it will be. I cannot say that enough.
226533
A simple was to state it: The sensation that you react to, like a pinprick, or sudden shortening of your tendon (like when you slip) sends a message along the sensory axon.  This communicates with a motorneuron in your spinal cord, which immediately sends a signal to a muscle-so that you jerk your hand back from pain, or move your leg to catch yourself before you fall.  The whole sequence doesnt involve your brain at all, its all done in your spinal cord- a single synapse.
140735
http://sloscience.hypermart.net/Biology/Frog%20Dissection/dorsal%20muscles.htm
457493
You should have asked this in a Medical category if you wanted more answers and quicker answers.\n\nTry these sites:\n\nhttp://www.spine-health.com/topics/cd/overview/lumbar/old/degen01.html\n\nhttp://www.spineuniverse.com/displayarticle.php/article243.html
413425
It depends on what area of the spine was injured and the extent of the injury.  Even people who were told they were paralyzed can make alot of progress,  there is a scientist I believe it was in Japan that was featured on Yahoo last summer where he had a girl who was paralyzed waist down, up and walking with some sensory equipment, not very far but still that's major progress.  Even Christopher Reeve, though paralyzed neck down could breathe at times without a respirator from rehab.  It just depends on how hard you work, where your injury is, to what extent you are injured, and how much rehab you have.
673269
It most likely will eventually. Nerves can regenerate.  I had the same experience and after maybe a year I noticed that the sense of feeling had returned.\n\nActually, it may have taken longer than a year to get completely back to normal but the point is that it did eventually.