Wednesday, November 16, 2011

Cranial nerves

Cranial nerves are nerves that directly out of the brain, others with spinal nerves that exit the spinal cord segments. In humans, there are twelve pairs of cranial nerves. Only the first and second pairs of nerves exit the large brain (cerebrum), the remaining 10 pairs of cranial nerves exit the brain stem.

Cranial nerve I - olfactory nerve
Is a sensory nerve, derived from telensefalon with the nucleus in the anterior olfactory nucleus. Its function is to receive excitatory odor; located in olfaktorii foramina in the ethmoid bone kribriform plates.

Cranial nerves II - optic nerve

Sensory nerves originating from the nucleus diensefalon on retinal ganglion cells. Functions to deliver visual information to the brain; located on the optical channel.

Cranial nerve III - The nerve Okulomotorius
Primarily motor, derived from the midbrain to the nucleus in okulomotorius nucleus, nucleus of Edinger-Westpal. Its function is to supply the levator muscle palpebra superior, superior rectus, medial rectus, inferior rectus, and inferior oblique, which generally supplies the eyeball movements; also supplies the muscles spincter pupil, and the muscles of the body siliar. Located in superior orbital fissure.

Cranial nerve IV - The nerve trokhlearis
Primarily motor, derived from the midbrain. Trochlear nerve supplies the superior oblique muscle, which moves the eyeball downward, or sideways spins (on the optical axis), and intorts eyeball; Located in superior orbital fissure.

V cranial nerve - the trigeminal nerve
Is a sensory and motor nerves. Derived from the Pons. Trigeminal sensory nuclei in the nucleus, spinal trigeminal nucleus, mesencephalic trigeminal nucleus, motor trigeminal nucleus. Its function is to receive stimuli from the face and the muscles of mastication; located in the superior orbital fissure (nerve oftalmikus - V1), foramen rotundum (nerve maxillaris - V2) and foramen ovale (mandibular nerve - V3)

VI cranial nerve - The nerve Abdusen
Primarily motor. Derived from the Pons posterior margin of the core premises in the nucleus abdusen. Abdusen nerve supplies the lateral rectus muscle, which serves for the abduction of the eyeball; located in the superior orbital fissure.

VII cranial nerve - facial nerve
Is a sensory and motor nerves. Derived from the Pons (serebelopontin angle) above the olive. In the nucleus of the facial nucleus, nucleus solitarius, nucleus salivarius superior. The facial nerve supplies the muscles of facial expression, posterior belly muscles digastrik, and stapedius muscle. Sensory nerves receive excitatory taste of 2 / 3 anterior tongue, and supplies the salivary glands (except parotid gland) and glands lakrimalis; located in the internal acoustic canal, extending into the facial canal and exits the foramen stilomastoideus.

VIII cranial nerve - The nerve Vestibulokokhlearis (or vestibulo-auditory nerve or nerve statoakustikus)
Primarily sensory. Located in the lateral facial nerve (serebelopontin angle). The vestibular nuclei, and kokhlear. Receive excitatory noise, rotation and gravity (for balance and body movement). More specifically, the vestibular branch carry impulses for hearing; located in the internal acoustic canal.

IX cranial nerve - The nerve Glossofaringeus

Is the motor and sensory nerves. Derived from the medulla. Nucleus ambiguus, the nucleus of the inferior salivarius, the nucleus solitarius. Glossofaringeus receive excitatory nerve flavor of 1 / 3 back of the tongue, supply the parotid gland, and supplies the motion stilofaringeus. Some are also in the relay sensations to the brain from tonsila palatine. Sensation in the relay to the opposite side of the thalamus and some hypothalamic nuclei. located in the jugular foramen.

Cranial nerve X - vagus nerve
Is a sensory and motor nerves. Out of the sulcus posterolateral medulla. Nucleus ambiguus, dorsal motor vagal nucleus, nucleus solitarius. The vagus nerve supplies the motion brakhiomotorik for almost all the muscles of the pharyngeal and laringeral (except stafilofaringeus muscle, which is innervated by the nerve glossofaringeus); of the vagus as well as parasympathetic fibers to nearly all organs of the chest and abdominal viscera down to the flexure splenikus; and the vagus also receive a special taste sensation of the epiglottis. The main functions: to control the muscles of the sound and resonance. Symptoms of damage: dysphagia (trouble swallowing), velofaringeal insufficiency. Located in jugular foramen.

Cranial nerve XI - accessory nerve (or cranial accessory nerve or spinal accessory nerve)
Primarily motor. Derived from cranial and spinal roots. Nucleus ambiguus, nucleus asesorium cord. Nerve function is to control the sternokleidomastoideus and trapezius muscles, along with the function of the vagus. Examples of symptoms: inability shrug, weak head movement; located in the jugular foramen.

XII cranial nerves - nerves Hipoglosus
Is a motor nerve. Derived from the medulla. hipoglosal core. movement of the muscles of the tongue (except muscles are innervated palatoglossus of the vagus) and other glossal muscles. Important for swallowing (bolus formation) and the articulation of language. located on the canal hipoglosal.

Because of the importance of considering all the cranial nerves during nervous system examination, many created mnemonic to help remember names and cranial nerve function. The three most widely used mnemonic, for example:
"On Old Olympus's Towering Tops, A Fine-Vested German Viewed Some Hops,"
"Oh, Oh, Oh To Take A Family Vacation! Go Vegas After Hours ", and
"Oh, Oh, Oh, To Touch And Feel, A Good Velvet, Ahh, Heaven."
"Old Opie occasionally tries TRIGonometry And Feels Very Gloomy, Vague, And hypoactive"
And also there is a mnemonic to remember the kind of sensory (S) or motoris (M), or Both / Both (B), namely:
"Some Say Money Matters But My Brother Says Big Brains Matter Most".