The Brainstem Flashcards
the brainstem is made up of
medulla oblongata
pons
midbrain
the brainstem occupies the ________ of the skull
posterior cranial fossa
the brainstem extends from the _______ to the __________
pyramidal decussation to the posterior commisure
blood supply of the brainstem
vertebrobasilar
the brainstem contains all the important nuclei of CN ____
3-12
the brainstem contains important reflex centers associated with the control of _____
respiration and the CV system and control of consciousness
smallest and least differentiated division of brainstem
midbrain (mesencephalon)
the midbrain comprises 2 lateral halves called the
cerebral peduncles
the midbrain is divided into
anterior crus cerebri and posterior tegmentum
the midbrain mediates what reflexes
auditory and visual
the midbrain contains
substantia nigra
largest nucleus of Mb and paramedian reticular formation
the midbrain extends from the _____ to the _____
superior medullary velum to the posterior commisure
3 parts of midbrain
- Tectum
- Tegmentum
- Crura Cerebri
the tectum lie dorsal to
cerebral aqueduct
the tectum is formed by
2 pairs of colliculi and corpora qaudrigemina
the superior and inferior colliculi together with the corpora qaudrigemina forms the
tectum
contain neurons that receive visual as
well as other input and serve ocular reflexes
superior colliculi
involved in auditory reflexes and in
determining side on which sound originates
inferior colliculi
round eminences on posterior
surface.
corpora quadrigemina
central part of the midbrain
tegmentum
the tegmentum is ventral to
cerebral aqueduct
the tegmentum contains
- oculomotor nuclei
- mesenphalic
- reticular formation
red nuclei
the red nucleus receives
crossed efferent fibers from cerebellum
the red nucleus is characterized by
pinkish yellow color (high vascularization)
the red nucleus sends fibers to
thalamus and contralateral spinal cord
the red nucleus is an important component for
motor coordination
this contains descending cortical projections
crura cerebri
the crura cerebri contains _______ projections
descending cortical
this contributes to the formation of crossed tectospinal tracts
colliculi
the colliculi contributes to the formation of
crossed tectospinal tracts
deep depression in the midline
interpeduncular fossa
boundary of interpeduncular fossa
crus cerebri
region where many small
blood vessels perforate the floor of interpeduncular fossa
Posterior perforated substance
emerges from a groove on medial
side of crus ceribri
occulomotor nerve
Separates tectum from tegmentum
Cerebral aqueduct
Separates midbrain tegmentum from crus cerebri
Substantia nigra
Contains descending autonomic tracts, endorphinproducing
cells (suppress pain)
Periaqueductal Gray matter
Contains efferent fibers from dentate nucleus of cerebellum
to opposite red nucleus and vental spinocerebellar tracts
Superior Cerebellar Peduncle
the inferior colliculus forms part of the
auditory pathway
superior colliculus forms part of the
visual reflexes
what connects the superior colliculus to the lateral geniculate body
superior brachium
the pons contains
auditory relay nuclei and vestibular nuclei
the pons is connected to the cerebellum by
middle cerebellar peduncle
the facial and abducens nucleus forms the
facial colliculus
CN found in pons
5-8
the dorsal tegmental portion of the pons is a continuation of the
reticular formation of the medulla oblongata
in the lower part of the pons are collected into a distinct
strand, named the
trapezoid body.
In the substance of the trapezoid body is a collection of
nerve cells, which constitutes the
trapezoid nucleus
continuous with those of the medulla oblongata
longitudinal fibers
small mass of gray substance situated on the dorsal
surface of the lateral part of the trapezoid body
superior olivary nucleus
most caudal segment of the brainstem
medulla oblongata
appearance of pyramids on anterior surface partially
obliterates the
anterior median fissure
swelling on each side of the median fissure,
pyramid
the pyramid is composed of
bundles of nerve fibers and corticospinal fibers
oval elevations produced by underlying inferior olivary
nuclei
olives
emerge from the groove between pyramid
and olive
hypoglossal nerve
the hypoglossal nerve emerge from
groove between pyrmaid and olive
posterior to olives, connect
medulla to cerebellum
inferior cerebellar peduncles
elongated swelling produced by gracile
nucleus
gracile tubercle
swelling lateral to gracile tubercle, produced
by underlying cuneate nucleus
cuneate tubercle
the supraspinal nucleus is composed of
somatic motor neurons extending to the lower medulla
the fiber tracts of white matter have the same arrangements as in
cervical spinal segments
a stalk-like bundle of fibers containing 1 or
more axon tracts.
peduncle
all fibers of the inferior cerebellar peduncle are ______ to the ______
afferent to the cerebellum
Cell groups lying along the midline of medulla, pons, and
midbrain.
raphe nuclei
the raphe nuclei and midbrain are sources of
ascending projections
tectospinal tract mediates ________ in
response to____ stimuli
reflex postural movements; visual and auditory
the corticoreticular fibers terminate in
portions of the pons and medulla
the cerebelloreticular fibers terminate in the
paramedian reticular nuclei
the cerebelloreticular fibers originate from
fastigial and dentate nuclei
the central tegmental tract terminate in
intralaminar and thalamic nuclei
the central tegmental tract plays an important role in
mechanism of arousal and sleep
caused when one hemisphere swells and pushes the
cingulate gyrus by the falx cerebri
cingulate or subfalcine herniation
consist of caudal displacement of the diencephalon,
midbrain and pons
central herniation
ncrease pressure to the cerebellar fossa
causes the cerebellum to move up through the tentorial opening
cerebellar herniation
The cerebellar tonsils herniate through the foramen in
magnum in
tonsillar herniation
in tonsillar herniation the cerebellar tonsils herniate through the
foramen magnum
