What Are The Twelve Cranial Nerves?

What are the Twelve Cranial Nerves? Cranial nerves are nerves which emerge directly from the brain and transfer data directly to the desired specific cells. In contrast, all other nerves within the human body emerge from the spine and then data is transfered from the spine to the brain. The first 2 cranial nerves emerge from the cerebrum, where as the remaining 10 cranial nerves emerge from the brain stem directly.

These are the 12 cranial nerves:

Cranial Nerve I

The first cranial nerve is the Olfactory nerve and serves the primary function to transmit nerve impulses from the nose to the brain in order to develop and achieve a sense of smell.

Cranial Nerve II

The second cranial nerve is the Optic nerve, which serves the primary function to transmit nerve impulses (messages) from the eye to the brain to achieve vision.

Cranial Nerve III

The third cranial nerve is the Oculomotory nerve, which serves the primary function to transmit nerve impulses from the eye muscles to the brain, to achieve eye movement (this includes dilation and constriction of the pupils.

Cranial Nerve IV

The fourth cranial nerve is the Trochlear nerve, and serves the primary function to transmit nerve impulses from the external eye muscles to the brain in order to achieve eye movements.

Cranial Nerve V

The fifth cranial nerve is called the Trigeminal serves the purpose of transmitting messages from the skin around the head all the way through to the teeth in order to achieve the sensations within the face, mouth and also in order to produce mastication.

Cranial Nerve VI

The sixth cranial nerve is called the Abducens nerve and transmits information from the brain to the eyes in order to turn the eyes outward.

Cranial Nerve VII

The seventh cranial nerve is called the Facial nerve, and as the name suggests it serves the purpose of providing contraction and movement of the facial muscles in order to achieve facial expression, as well as producing a sense of smell.

Cranial Nerve VIII

The eighth cranial nerve is called the Acoustic nerve and as the name suggests in transmits nerve impulses from the ear to the brain in order to achieve the sense of hearing and balance (as associated with the middle ear).

Cranial Nerve IX

The ninth cranial nerve is called the Glossopharyngeal nerve, and is involved in proving a sense of taste, swallowing, movement of the throat and excretion of saliva during mastication.

Cranial Nerve X

The tenth cranial nerve is called the Vagus nerve and transmits nerve impulses from the throat, larynx, and organs in the thoracic and abdominal cavities through to the brain in order to maintain many homeostatic purposes, such as parasympathetic stimulation.

Cranial Nerve XI

The eleventh cranial nerve is called the Spinal Accessory nerve and transmits impulses from the brain to certain shoulder and neck muscles in order to achieve movements such as turning and head control.

Cranial Nerve XII

The twelfth and final cranial nerve is called the Hypoglossal nerve and transmits nerve impulses from the brain o the muscles of the tongue in order to achieve tongue movement.