 The head and facial muscles are unique ◦ For the most part skeletal muscles originate and insert on the skeleton (bones!) ◦ The head and facial muscles often originate and/or insert on connective tissue or other muscles  The head and face muscles are grouped by jobs ◦ Facial expression ◦ Mastication ◦ Some muscles are responsible for both  The neck muscles’ actions affect the head, and also the structures inferior to the neck

 O: Cranial aponeurosis  I:Skin of eyebrows and nose  I:Facial nerve  A:Raises eyebrows and wrinkles forehead skin  (Aponeurosis – a broad, flat connective tissue, similar to a tendon, that binds muscles together and connects them to bone)

 O: Frontal bone and maxilla  I:Skin of eyelid  I:Facial nerve (temporal & zygomatic branches)  A:Blinking, squinting, and forceful closing of eyelids

 O: Zygomatic bone  I:Skin of superior mouth  I:Facial nerve (zygomatic branch)  A:Draws angle of mouth upward and laterally (smile!)

 O: Maxilla & mandible  I:Fibers of orbicularis oris  I:Facial nerve (buccal branch)  A:Compresses cheeks against teeth; synergist in chewing

 O: Tubercle of mandible  I:Mouth  I:Facial nerve (mandibular branch)  A:Depresses angle of mouth (frown)

 O: Anterior mandible  I:Chin  I:Facial nerve (mandibular branch)  A:Elevates & wrinkles skin of chin; protrudes lower lip

 O: Occipital bone & mastoid process of temporal bone  I:Galea aponeurosis  I:Facial nerve (posterior auricular branch)  A:Wrinkle brow; lift eyebrows

 O: Maxilla  I:Nasal bone  I:Facial nerve (buccal branch)  A:Compresses bridge of nose; depresses tip; elevates corners of nostrils

 O: Fibers of other mouth muscles  I:Muscles and skin at angle of mouth  I:Facial nerve (buccal branch)  A:Closes and protrudes lips

 O: Pectoralis & deltoid  I:Mandible & skin of mouth  I:Facial nerve (cervical branch)  A:Depresses mandible; draws angle of mouth downward; tightens skin of neck

 O: Zygomatic arch  I:Mandible  I:Mandibular nerve  A:Elevates mandible

 O: Temporal fossa  I:Coranoid process of mandible  I:Mandibular  A:Elevates and retracts mandible

 O: Sternum & medial clavicle  I:Mastoid process of temporal bone  I:Accessory nerve  A:Together – flex cervical column; Alone – rotate and flex neck to side

 O: Occipital bone & spinous processes of C 7 – T 12  I:Lateral clavicle, acromion process, & spine of scapula  I:Accessory nerve  A:Upward rotation, retraction, elevation, & depression of scapulae; extension, rotation, and lateral flexion of neck

 O: Transverse processes of C 1 – C 4  I:Medial border of scapula  I:Cervical nerves C 3 – C 5  A:Elevates scapula; rotates scapula downward; extends, rotates, and laterally flexes neck

 O: Cervical vertebrae C 2 – C 7  I:1 st and 2 nd ribs  I:Cervical nerves C 3 – C 8  A:Elevates ribs; flexes, laterally flexes, and rotates neck; synergist in inspiration