why do eyes rarely get paralysed?
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Paralysis is often the result of spinal cord injury. Most of the “cables” (nerve tracts) that connect your brain to your muscles and somatosensory organs go through the spinal cord. The lower the muscle, the further down the spinal cord the nerve tract goes before branching out into the body. So, the higher up the damage to the spinal cord occurs, the more of these tracts that get interrupted, and the higher up the paralysis goes. If the damage is very low down, you might only get paralyzed in your legs, but if it’s higher, the paralysis might include e.g. the muscles in your pelvis, torso, arms, neck and so forth.
However, the eyes aren’t connected to the brain via the spinal cord. They send visual information to the brain via the *optic nerve*, and the brain sends motor commands to the eyes via the *oculomotor nerve*. These are two of a total of twelve so-called *cranial nerves.* The cranial nerves all connect to the brain without passing through the spinal cord, and are protected by the skull. As such, they aren’t vulnerable to neck or back injuries, which are a main source of paralysis (along with strokes and other damage to the brain itself).
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