Neurosciences & Brain Imaging Open Access

Cranial Nerve

Cranial nerve connect the muscles and sense organs of the head and thoracic region directly to the brain.Cranial nerves relay information between the brain and parts of the body, primarily to and from regions of the head and neck. Cranial nerves have paths within and outside the skull.

The paths within the skull are called "intracranial" and the paths outside the skull are called "extracranial".All cranial nerves are paired, which means that they occur on both the right and left sides of the body. The cranial nerves leave the brain via their own individual apertures in the skull.

Twelve Pairs of cranial nerves are I Olfactory (Smell), II Optic (Sight), III Oculomotor (Moves eyelid and eyeball and adjusts the pupil and lens of the eye), IV Trochlear (Moves eyeballs), V Trigeminal (Facial muscles incl. chewing; Facial sensations), VI Abducens (Moves eyeballs), VII Facial (Taste, tears, saliva, facial expressions), VIII Vestibulocochlear (Auditory), IX Glossopharyngeal (Swallowing, saliva, taste), X Vagus (Control of PNS e.g. smooth muscles of GI tract), XI Accessory (Moving head & shoulders, swallowing), XII Hypoglossal (Tongue muscles - speech & swallowing).