Pathways of a Simple Reflex
The minute your skin touches a hot pan, an impulse travels from one end of a nerve in your skin to your spinal cord. Here the nerves leading from the spinal cord to the muscles of your arm transfer the impulse rapidly. The result is a quick jerk. The whole process takes a fraction of a second. Can you think that fast? If your hand had stayed on the pan until you decided what was wrong and what to do about it, you would have suffered a serious burn. You can observe another simple reflex more safely and painlessly. Cross you legs. Now strike your knee just below the kneecap with the edge of a book or a ruler. This knee jerk is a common test for reflex. When your doctor does this, he is merely checking the condition of your nerves and your spinal cord. Those tests simply test the state of your nerves if they are functioning well, And if they are in good condition.
