What is a person's "reflex action"?

What is a person's "reflex action"?

If I were to tap your knee you would get a reflex action. When I tap the knee and your leg moves, it is because you tell your spinal cord that your knee has been tapped. So if you tap the knee, an impulse goes into the spinal cord, but it doesn't necessarily have to go up to the brain. It goes directly to the motor neuron, and the leg moves. There are diseases which will interfere with that. If the peripheral nerve is involved, your spinal cord may not know that you have been tapped, so the leg doesn't move. If the motor neuron has been damaged or the peripheral nerve has been damaged where the motor fiber is involved, it won't move either. So that is a reflex action. Although there is control over that, some people's reflexes are very brisk and some people's are not, that's from the brain and central nervous system, that's from up above. Movement - if you burn your hand and you pull it away, you don't need your brain, so that's being done on a spinal cord level. That's not going up very high. The fact that it hurts is going up high, but you could burn yourself and it could be a second or two before you realize you've hurt yourself, but you would have moved your hand before that. That would be the reflex.