Dr. Michael P. Gillespie. Between the brain and spinal cord. 3 regions. Medulla oblongata. Pons. Midbrain. 2 Dr. Michael P. Gillespie.

Dr. Michael P. Gillespie

Between the brain and spinal cord.3 regions.

Medulla oblongata.Pons.Midbrain.

2Dr. Michael P. Gillespie

A continuation of the spinal cord.Sensory (ascending) tracts and motor

(descending) tracts travel through the white matter of the medulla.

Many nerves decussate (cross over) in the medulla.


Cardiovascular center regulates the heartbeat and the diameter of the blood vessels.


The medullary rhythmicity area adjusts the rhythm of the breathing and controls reflexes for vomiting, coughing, and sneezing.


The nuclei for the following cranial nerves reside in the medulla:VIII (vestibulocochlear).IX (glossopharyngeal).X (vagus).XI (accessory).XII (hypoglossal).


Pneumotaxic area and apneustic area regulate breathing.

Nuclei for cranial nerves V (trigeminal), VI (abducens), and VII (facial).


The midbrain or mesencephalon contains the superior colliculi (visual actvities) and inferior colliculi (auditory pathways).

The midbrain contains the substantia nigra which release dopamine to help control subconscious muscle activities. Loss of these neurons results in Parkinson disease.

Cranial nerves III (oculomotor) and IV (trochlear) originate here.







Type: sensory.Function: smell.Anosmia – loss of sense of smell.Does not connect with the brainstem.



Type: sensory.Function: vision.Anopia – blindness in one or both eyes.


Type: mixed (mainly motor).Function: movement of the upper eyelid

and eyeball. Accomodation of the lens for near vision and constriction of the pupil.

Strabismus – deviation of the eye in which both eyes don’t focus on the same object.

Ptosis – drooping of the upper eyelid.Diploia – double vision.


Type: mixed (mainly motor).Function: movement of the eyeball.Diplopia and strabismus occur with trochlear

nerve damage.



Type: mixed.Function: conveys impulses for touch, pain,

temperature and proprioception. Chewing.Trigeminal neuralgia (tic douloureux) – pain

to branches of the trigeminal nerve.Dentists apply anesthetic to branches of this

nerve.



Type: mixed (mainly motor).Function: movement of the eyeball.With damage to this nerve the eye cannot

move laterally beyond the midpoint and usually points medially.



Type: mixed.Function: Propriception and taste. Facial

expression. Secretion of saliva and tears.Injury produces bell’s palsy (paralysis of

facial muscles).



Type: mixed (mainly sensory).Function: conveys impulses for equilibrium

and hearing.Injury can cause vertigo, ataxia (muscular

incoordination), nystagmus (rapid movement of the eyeball), and tinnitus.


Type: mixed.Function: taste and somatic sensations from

the posterior 1/3 of the tongue. Elevates the pharynx during swallowing and speech. Stimulates the secretion of saliva.

Injury causes decreased salivary secretion, loss of taste, and difficulty swallowing.



Type: mixed.Function: taste and somatic sensations.

Swallowing, coughing, and voice production. Regulates GI tract and heart rate.

Injury interferes with swallowing, paralyzes vocal cords, and causes the heart rate to increase.



Type: mixed (mainly motor).Function: Proprioception. Swallowing,

movement of head and shoulders.If the nerves are damaged the SCM and

Trapezius become paralyzed.



Type: mixed (mainly motor).Function: Proprioception. Movement of the

tongue during speech and swallowing.Injury results in difficulty in chewing,

speaking, and swallowing. When protruded, the tongue curls towards the affected side and atrophies on the affected side.



I – OlfactoryII – OpticIII – OculomotorIV – TrochlearV – TrigeminalVI – Abducens

VII – FacialVIII – Auditory

(Vestibulocochlear)IX –

GlossopharyngealX – VagusXI – Spinal accessoryXII - Hypoglossal


On Old Olympus’ Towering Tops A Fin And German Viewed Some Hops.

This mnemonic device helps you memorize the names of the cranial nerves.

The first letter from each word corresponds to the first letter of each cranial nerve.


Some Say Marry Money, But My Brother Says Big Brains Matter Most.

This mnemonic device helps you memorize the sensory / motor distribution of the cranial nerves.

S = sensoryM = MotorB = Both


Twelve pairs of cranial nerves exit from the brain and brainstem.

These nerves innervate the face, head, and neck.They control all sensory and motor functions in

these areas including the special senses of vision, hearing, smell, and taste.

Cranial trauma, infections, aneurysm, stroke, degenerative diseases (i.e. multiple sclerosis), upper motor neuron lesions, lower motor neuron lesions, increased intracranial pressure, and abnormal masses or tumors can all affect the cranial nerves.


Some facial movements are performed in bilateral synchrony such as swallowing and moving the forehead and are thus innervated bilaterally.

Fine movements of the face are unilateral. The contralateral hemisphere innervates the affected area.


Dr. Michael P. Gillespie. Between the brain and spinal cord. 3 regions. Medulla oblongata. Pons. Midbrain. 2 Dr. Michael P. Gillespie.

Documents

trigeminal nerve

gillespiethe midbrain

cranial nerves v trigeminal

following cranial nerves

trochlear nerve damage

gillespiethe nuclei

medulla oblongata

sensory ascending tracts