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Old 06-24-2012
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Default Clasp Knife response

Hello guys quite confused with this response mechanism. Can someone explain this in layman's language. As i already read in KLN and Wiki but not able to get the point exactly. Thanks.
One day i will infect these microbes and they will search for "Anti-MEbiotic"....
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Old 06-24-2012
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It's pretty simple actually.
1. In UMN palsy, there's increased A-gamma motor neuron firing to the muscle spindle, making them more sensitive to stretch. So you have exaggerated reflexes and greater resistance to passive stretch. thats what we call spasticity.
2. However that being said, the golgi tendon organs are still functional(they function through a spinal reflex(Ib and A-alpha), so they're not affected). So when the muscle tendon is stretched beyond a certain point, there's relaxation of the muscle giving rise to a sudden release, like a clasp knife.

I hope you've understood. This is explained beautifully in Ganong physiology if you want to read up further.
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