Why does decussation of the motor and sensitive tracts in the nervous system occur?

Question

Why do the motor and sensitive tracts cross on their way to the cerebrum? I can't seem to find a reasonable explanation for this phenomenon.

Answer 1

I don't know if there is a scientific answer to this. However, I have postulated that it is a matter of protection. If an attack or injury comes from the left side and damages the brain/nervous system, the right brain can still provide defensive maneuvers to the left side of the body.