Medulla Flashcards
Where does the corticospinal tract decussate?
ventral medulla
Where are the pyramids found in the brainstem?
ventral medulla
What three structures are in the ventral medulla?
- Pyramids
- Inferior olives
- Motor decussation
What is found in the pyramids of the ventral medulla?
Corticospinal tracts
What is found in the inferior olives of the ventral medulla?
inferior olivary complex
What is found in the tuberculum cinereum of the ventral medulla?
Spinal nucleus and trigeminal tract
What four structures are found in the dorsal medulla?
- 4th ventricle
- Fasciculus gracilis
- Fasciculus cuneatus
- Inferior cerebella peduncle
What is found in the Gracile and Cuneate tubercles of the dorsal medulla?
Nucleus gracilis and Nucleus cuneatus
The 4th ventricle portion of the dorsal medulla is called _____ medulla
open (rostral)
The central canal portion of the dorsal medulla is called _____ medulla
closed (caudal)
What three structures are in the open medulla?
- Hypoglossal trigone
- Vagal trigone
- Lateral recess (vestibular and hearing)
Know the locations of the structures of the dorsal medulla (open and closed)
MEMORIZE DAT SHIT
What structures are found in the hypoglossal trigone?
hypoglossal nucleus
nucleus prepositus hypoglossi
Where is the dorsal motor nucleus of CN X?
Vagal trigone (vagus nerve… CN X)
Where does the 4th ventricle become the central canal of the spinal cord?
Obex
In what structure is there a hole in the blood brain barrier so the brain can detect toxins in the blood and trigger vomiting?
Area Postrema
where is the medulla developed from the 3-vesicle brain?
from the 5-vesicle brain?
3: rhombencephalon
5: myelencephalon
what are the boundaries of the medulla?
rostral: post pontine protuberance to 4th ventricle
caudal: foramen magnum (1mm to motor decuss)
What is the function of the Hypoglossal nucleus?
Move the tongue
CN XII
What is the function of the dorsal motor nucleus of X?
Viscera of thorax and adomen
CN X
What is the function of the Inferior salivatory nucleus?
Innervate parotid gland
CN IX
What is the function of the Motor Nucleus of IX, X and XI?
IX. Stylopharyngeus muscle
X. Pharynx and larynx (speech / swallowing)
XI. Laryngeal muscles
What is the function of the rostral Nucelus Solitarius of VII, IX, and X?
VII. Taste - ant. 2/3
IX. Taste - post. 1/3
X. Taste - root of tongue
(Solitarius - eating a donut alone)
What is the function of the caudal Nucleus Solitarius of X, and IX?
X. Abdominal/thoracic viscera; larynx/pharynx, aortic body/sinus
IX. Carotid sinus/body, pharynx, auditory tube
Motor nuclei in the medula is _____ while sensory nuclei is _____
Motor - medial
Sensory - lateral
What is the function of the vestibular nucleus of VIII?
Inner ear (vestibular division)
What is the function of the cochlear nucleus of VII?
Inner ear (auditory division)
What is the function of the spinal trigeminal nucleus of V?
Skin face, forehead, anterior scalp, sinus cavities. ant 2/3 of tongue
What is the function of the spinal trigeminal of VII, IX, and X?
VII - skin behind ear
IX - post 1/3 of tonue
X - root of tongue
What are the cranial nerves associated with the medulla?
IX, X, XI, XII
CN XI lesions cause _____ LMN signs
unilateral LMN signs
can’t speak/chew/swallow
What does CN XI do?
Shrug shoulders, nod/shake head
What four nuclei does CN X transmit information to or from?
- Dorsal motor nucleus of X
- Nucleus ambiguus
- Nucleus solitarius
- Spinal trigeminal nucleus
* know these functions!*
What is the afferent and efferent limb of the gag reflex?
afferent: CN 9
efferent: CN 10
* this is on test!*
Cranial nerves arise _____ in the brainstem and emerge ______
arise dorsal (nuclei) emerge ventral (rootlets)
A lesion in the medulla leading to many sensory problems is typically due to a stroke of the _____ or _____
PICA (posterior inferior cerebellar artery) or
vertebral artery
lateral brainstem syndromes are due to srokes of the _______ blood supply branches
circumferential
medial brainstem syndromes are due to stroke of the _________ blood supply branches
parameridian
PICA (posterior inferior cerebellar artery) can play a significant role in _______ syndrome
Wallenberg
Damage to the nucleus ambiguus would lead to ______
difficulty swallowing
Damage to the descending autonomics would lead to ______
Horner’s Syndrome
Medial Medullary Syndrome affects what three structures?
- medial lemniscus (contra)
- CN XII (ipsi)
- Corticospinals (contra)
When you see facial analgesia on one saide and opposite body pain and temp loss, you are where? and what side?
Medulla
side of Horner’s Syndrome
What are the symptoms of Wallenberg’s Syndrome?
- Spinal nucleus and tract of V (loss of ipsi pain/temp)
- Spinothalamic tract (loss of contra pain/temp)
- Ipsi ataxia
- Ipsi nucleus ambiguus failure
- Ipsi Horner’s Syndrome (descending sympathetic)
- Lost corneal reflex
what is the function of the tract of V
the head’s version of Lissauer’s tract/substatia gelatinosa-conveys pain and temp sensations from the IPSIlateral face
what do raphe nuclei do
where are they located
secrete and synthesize serotonin (5HT)
along the midline
