The trigeminal motor nucleus contains
motor neurons that innervate muscles of the
first branchial arch, namely the muscles of
mastication
Chewing or mastication is the process by which food is crushed and ground by teeth. It is the first step of digestion, and it increases the surface area of foods to allow a more efficient break down by enzymes. During the mastication process, th ...
, the
tensor tympani,
tensor veli palatini,
mylohyoid, and anterior belly of the
digastric
The digastric muscle (also digastricus) (named ''digastric'' as it has two 'bellies') is a small muscle located under the jaw. The term "digastric muscle" refers to this specific muscle. However, other muscles that have two separate muscle bellie ...
. This nucleus is located in the mid-pons (i.e. in the center of the pons going inferior to superior).
Brainstem Nuclei of the Cranial Nerves at wustl.edu
Lesion
The trigeminal motor nucleus forms the efferent pathway of the jaw jerk reflex The jaw jerk reflex or the masseter reflex is a stretch reflex used to test the status of a patient's trigeminal nerve ( cranial nerve V) and to help distinguish an upper cervical cord compression from lesions that are above the foramen magnum. The ...
. Since the axons involved in this reflex do not decussate, a lesion involving the trigeminal motor nucleus would cause ipsilateral hemiparesis.
References
External links
Washington University
Cranial nerve nuclei
Trigeminal nerve
Pons
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