lecture 9 brainstem Flashcards
(37 cards)
what 2 types of tracts does the brain stem carry?
- ascending sensory tracts- dorsally located
- descending motor tracts- ventrally located
what 6 descending tracts originate in the brain stem?
- tectospinal
- rubrospinal
- retciulospianal
- vestibulospinal
- ceruleospinal
- raphespinal
what two things are located on the brainstem?
cranial nerve nuclei and colliculi
what is the ventral division of the brainstem?
basilar- structures related to motor activity
what is the dorsal division of stem proper?
tegmentum- structure related to sensory input
what is the additional dorsal layer of the brainstem?
tectum- structures related to orienting the auditory and visual input
what is the function of the medulla?
coordination of the head/ neck movement, breathing, swallowing, HR
what 5 structures does the medulla contain?
- pyramids: descending motor tracts; pyramidal decussation- lateral corticospinal tract
- olives: inferior olivary nucleus: projections to cerebellum and spinal cord (climbing fibers)
- cranial nuclei: 5,7-10,12
- cuneate and gracilis tubercles
- ascending tracts
What is the function of the basilar portion of the pons?
descending tracts from cortex to pons and spinal levels (corticospinal tracts)
what is the function of the tegmentum portion of the pons?
ascending sensory tracts, reticular formation, ANS pathways, sensory CN nuclei 5,6,7, medial longitudinal fasciculas tract for coordination of eye and head
what is the function of the tectum?
posterior to the tegmentum at midbrain level controlling eye muscles and head orientation to sight and sounds
- pretectal area-aids in pain control; located between the colliculi and cerebral aqueduct
- superior and inferior colliculi
what type of CN nuclei is VIII?
special for sensory and motor- located in the pons
what CN has a somatic function for sensory input?
V
what 3 CN have a visceral function for sensory input?
VII, IX, X
what 4 CN are motor and have visceral function?
III, VII, IX, X
what 5 CN are motor and have brachial functions (swallowing, speech production)
V, VII, IX, X,XI
what 4 CN are motor and have somatic function (muscle)?
III, IV,VI, XII
what are the 3 functions of the reticular formation?
- integrates sensory and cortical info
- regulates motor and autonomic functions and consciousness
- modulates ascending pain with defending influences
where is dopamine located and what is its function?
Ventral tegmental nuclei
-decision making, feeling or pleasure and addiction
where is acetylcholine located and what is its function?
Pedunculopontine
-influences movement vis basal ganglia, vestibular and recticulospinal connections
where is serotonin located and what is its function?
raphe nuclei
-mood, movement modulator, pain inhibition, cardiovascular regulation
where is norepinephrine located and what is its function?
locus ceruleus
-attention/ sleep regulation, pain inhibition
where are norepinephrine and epinephrine located and what is the function?
medial reticular area
-autonomic regulation of respiration, viscera, cardiovascular response
what structure is located posterior to the cerebral peduncles?
substantia nigra
