The axons of upper motor neuron cross to the opposite site of the brain.
Multipolar neurons are found in the cerebral cortex, amygdala. Pyramidal neurons are usually primary excitation unit of mammalian prefrontal cortex and corticospinal tract. Pyramidal tracts such as the corticospinal tracts and corticobulbar tract motor fibers are contained in the pyramids. The lower limit of pyramids is marked when the fiber crossed or decussate. Most of the fibers of the pyramidal tracts leave the pyramid in bundles and decussate in the anterior medial fissure of the medulla.