Corticobulbar tract
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The corticobulbar (or corticonuclear) tract is a white matter pathway connecting the cerebral cortex to the brainstem (the term "bulbar" referring to the brainstem).
The 'bulb' is an archaic term for the medulla oblongata. In clinical usage, it includes the pons as well.
The muscles of the face, head and neck are controlled by the corticobulbar system, which terminates on motor neurons within brainstem motor nuclei. This is in contrast to the corticospinal tract, which connects the cerebral cortex to spinal motor neurons, and controls movement of the torso, upper and lower limbs.
The corticobulbar tract innervates cranial motor nuclei bilaterally with the exception of the lower facial nucleus which is innervated contralaterally. Among those nuclei that are bilaterally innervated a slightly stronger connection contralaterally than ipisilaterally is observed.