Medulla Flashcards
dorsal column/medial lemniscal system
Fasciculus gracilis synapse with ____ afferents in ____
2° afferents in Nucleus Gracilis
dorsal column/medial lemniscal system
Fasciculus cuneatus axons synapse with ____
Nucleus Cuneatus
dorsal column/medial lemniscal system
Crossing Axons of both sets of DCML 2° afferents form ____
Internal Arcuate Fibers (crossing fibers)
Axons forming Internal Arcuate Fibers cross to the opposite site via….
the Great Sensory Decussation
What forms the Medial Lemniscus?
Tract of 2° afferents carrying deep sensibility from the contralateral half of the body (DCML)
When internal Arcuate fibers cross the great sensory decussation they form ____
Medial Lemniscus
Spinocerebellar tracts carry ____ from the ____
Proprioception from the lower body
Dorsal spinocerebellar tract enters the cerebellum via ____
The inferior cerebellar peduncle
Ventral spinocerebellar tract enters the cerebellum via ___
The superior cerebellar peduncle
What crosses at the great sensory decussation?
Internal Arcuate fibers (DCLM)
pain & temperature from ipsilateral face & other areas of the head enter the ____
spinal tract of the trigeminal nerve (CN V)
pain & temperature from the face
1° axons from the spinal tract of the trigeminal nerve synapse with ____ in the ____
secondary afferents in the nucleus of the spinal tract of trigeminal
pain & temperature from the face
secondary axons cross the midline to form the ____
trigeminal lemniscus
trigeminal lemniscus ends at the ____
thalamus
what carries pain & temperature from the contralateral side of the body to the thalamus?
spinothalamic tracts
spinothalamic tracts carry ____ neurons for ____
secondary afferent neurons for pain & temperature
the pyramid contains ____ to the ____ half of the body
corticospinal fibers (UMNs) to the contralateral side of the body
at the pyramidal decussation, ____% of fibers cross to form the ____
85%
lateral corticospinal tract
at the pyramidal decussation, ____% of fibers do not cross, and form the ____
15%
ventral corticospinal tract
tract connecting cranial nerve nuclei and autonomic centers to coordinate vestibular input & head, neck, and eye movements
connects cranial nerves that move the eyes
medial longitudinal fasciculus (MLF)
medial longitudinal fasciculus is involved in ____
conjugate horizontal eye movements (eyes move in synchrony)
lesion to medial longitudinal fasciculus causes ____
internuclear opthalmopegia
eyes cannot move in synchrony
synchronous eye movement requires coordination through the ____
medial longitudinal fasciculus
diffuse area in the brainstem with small nuclei and fibers
reticular formation
reticular formation is involved in ____
autonomic functions
- sympathetic & parasympathetic
- includes cardiovascular & respiratory centers
what is responsible for maintaining consciousness & alertness by monitoring sensory stimuli?
reticular activating system
what is responsible for breathing rate & HR?
reticular formation
lesion of reticular formation may lead to ____
coma or death
the hypoglossal nucleus is located under ___
hypoglossal trigone
hypoglossal nucleus contains ____
cell bodies of LMNs to ipsilateral tongue muscles
dorsal motor nucleus of the vagus is a ____
parasympathetic nucleus for respiratory system, heart, and GI system
dorsal motor nucleus is mostly for the ____ nerve
vagus nerve (CN X)
vestibular nuclei receive afferents from the ____
vestibulocochlear nerve (CN VIII)
vestibulocochlear nerve contains afferents responsible for ____
balance & equilibrium
vestibular nuclei project to the…
spinal cord, cerebellum, MLF
solitary tract & nucleus receives taste fibers from the ____, ____, and ____ nerves
facial (CN VII)
glossopharyngeal (CN IX)
vagus (CN X)
involved in afferent autonomic limb of visceral reflexes of cardiovascular and GI systems
solitary tract & nucleus
What is the motor nucleus to the ipsilateral muscles of larynx, pharynx and palate?
Nucleus ambiguus
What nerves innervate larynx, pharynx, and palate?
Glossopharyngeal (CN IX)
Vagus (CN X)
Accessory (CN XI)
What nerve innervates stylopharyngeus muscle?
CN IX - glossopharyngeal
What nerves innervate other laryngeal, pharyngeal and palatal muscles by means of the Vagus?
CN X Vagus
CN XI accessory
Lesion of nucleus ambiguus or CN X leads to…
Dysphonia (hoarseness speaking)
Dysphasgia (difficulty swallowing)
Uvula deviation to good side due to paralyzed innervated muscles
Inferior Olivary nucleus is involved in ____
Motor control
Inferior olivary nucleus receives input from ____
Spinal cord, cortex, and other areas
Inferior olivary nucleus projects to ____
Cerebellum
What is the Inferior cerebellar peduncle?
A large bundle of fibers, mostly going to the cerebellum
Inferior cerebellar peduncle contains…
Dorsal spinocerebellar tract (DSCT) and olivocerebellar fibers
Dorsal cochlear nucleus receives fibers involved in…
Hearing
Dorsal cochlear receives fibers from…
Vestibulocochlear nerve (CN VIII)
What are Olivocerebellar fibers?
Axons involved in motor control from inferior olivary nucleus to contralateral cerebellum
Dorsal cochlear nucleus is located in…
Acoustic tubercle
What nuclei are located in the lower medulla?
Nucleus of trigeminal
Nucleus gracilis
Nucleus cuneatus
What nuclei are located in the middle medulla?
Vestibular
Solitary
Dorsal motor nucleus of X
Hypoglossal
Ambiguus
Inferior olivary
What nuclei are located in the upper medulla?
Inferior olivary
Ambiguus
Hypoglossal
Dorsal motor nucleus of X
