The facial nerve emerges from the brainstem with the nerve of Wrisberg, ie, the nervus intermedius see the image below. The skin of the face has large number of sweat and sebaceous glands. The medical information on this site is provided as an information resource only, and is not to be used or relied on for any diagnostic or treatment purposes. The facial motor nuclei then send signals to the orbicularis oculi muscles of both eyes to contract via the temporal and zygomatic branches of the facial nerve. Muscles of the nose b. For the innervation of facial muscles, the corticobulbar tract sends motor signals via a sequence of two motor neurons: More prolonged and sustained muscle spasms may also be present separated by periods of absent muscle activity.
The Muscles of Facial Expression
The facial nerve and the nervus intermedius enter the IAC with the vestibulocochlear nerve. Orbicularis oris Marginal mandibular branch Risorius. Input from the trigeminal nerve and nucleus form the basis of the trigeminofacial reflexes; eg, the corneal reflex. Regarding facial expression, there is one vitally important nerve that allows us to partake in this form of communication, and it is aptly named the facial nerve. The cortical motor area of the face is supplied by the artery of the central sulcus Rolandic artery from the middle cerebral artery. The fibres are ordered into upper, intermediate and lower groups. If the lesion occurs distally to the branching of the greater petrosal nerve and chorda tympani, lacrimation, salivation, and taste sensation in the anterior two-thirds of the tongue may be unaffected.
Anatomy: Head and Neck Table of Muscles
Pain fibers from the external acoustic meatus may be carried with this nerve. Vl ophthalmic to the orbit, V2 maxillary to the upper jaw, and V3 mandibular to the lower jaw. View full topic index. Organization of the facial nucleus and corticofacial projection in the monkey: The SMAS also helps the surgeon to identify the location of the facial nerve during dissection toward the midline of the face, where the nerve can be found running on top of the masseter muscle just below the SMAS.
With nuclear and infranuclear lesions, loss of involuntary and voluntary facial movement occurs. The facial nerve is composed of approximately 10, neurons, 7, of which are myelinated and innervate the nerves of facial expression. It includes muscles of facial expression, vessels and nerves and varying amount of fat. You need to be a gold member supporter to access this content. The facial muscles can broadly be split into three groups; orbital , nasal and oral. Share Email Print Feedback Close.