Facial expression analysis

Facial expressions refer to movements of the mimetic musculature of the face. The vast majority of these muscles are innervated by the VIIth cranial nerve, emanating from the brainstem between the pons and medulla (Figure 1). The nerve includes a motor root that supplies somatic muscle fibers to the muscles of the face, scalp, and outer ear, enabling the muscle movements that comprise facial expressions. The sensory part of the nerve enables and augments some aspects of taste and sound (Standring, 2005).