1 : the action of crossing (as of nerve fibers) especially in the form of an X. 2 : a crossed tract of nerve fibers passing between centers on opposite sides of the nervous system.

What is the purpose of decussation?

Objective: In the chordate and vertebrate central nervous system, sensory and motor nerve tracts cross from one side to the other as they connect the brain with sensory receptors and motor neurons. These "decussations," crossings in the form of an X, relate each side of the brain to the opposite side of the body.

What is a decussation in anatomy?

A decussation is an intersection of pathways in the form of an X. Most nerve pathways between our brain and spinal cord cross over at some point. This accounts for why each side of our brain (two cerebral hemispheres) has control over the opposite side of our body.