Very important descending motion controlling management path. Part of the pyramidal system.
Begins in the anterior central cortex of the primary motor cortex and ends in the brainstem, mainly on the opposite side, in various motor cranial nerve nuclei. Is important for the voluntary control of the muscles of the face (especially the muscles around the mouth opening and cheeks), mandible, tongue, pharynx and larynx. This involves more or less direct contacts between nerve cells in the 5th layer of the cerebral cortex and the motor neurons that control muscles of importance for speech, both phonation and articulation.
Note that the motor neurons of the eye muscle nuclei , with one exception, are NOT affected by the tr.cortico-nuclearis, but are controlled from different gaze directional centers.
The exception is the motor neurons of the nucleus oculomotorius that control the "eyelid lifter muscle"; Musculus levator palpebrae superior.