Exam 1 Brainstem and Cerebellum Flashcards
Brainstem Ventral surface features
~Pyramids ~Pyramidal decussation ~Olivary eminence (olive) ~Median fissure ~Cerebellar peduncles ~Basilar sulcus ~Transverse fibers of pons ~Cerebral peduncles ~Interpeduncular fossa ~Mammillary bodies & Infundibulum part of diencephalon ~cranial nerves
Pyramids
~from the medulla, we see medially and caudally
~separated by the median fissure and pyramidal decussation
Olivary eminence
~just lateral to the pyramids
Cerebellar peduncle
~large middle cerebellar peduncle
~inferior and superior cerebellar peduncles
Basilar sulcus
seen on the ventral surface of the pons along the midline
Transverse fibers of pons
radiating laterally on the ventral surface
Cerebral peduncles
in midbrain, we see the bilateral cerebral peduncles separated by the cavity
Interpeduncular fossa
the cavity the separates the cerebral peduncles
Mammillary bodies and infundibulum are part of
diencephalon (hypothalamus)
Which cranial nerves enters on the ventral surface of medulla?
CN XII, XI, X, IX
Which cranial nerves enters on the ventral surface of pontomedullary junction?
CN VIII, VII, VI
Which cranial nerves enters on the ventral surface of pons?
CN V
Which cranial nerves enters on the ventral surface of Midbrain?
CN III and IV
Which cranial nerves enters the cerebrum?
CN I
Which cranial nerves enter the diencephalon (thalamus)?
CN II
CN I-
olfactory
CN II-
optic
CN III-
oculomotor
CN IV-
trochlear
CN V-
trigeminal
CN VI-
Abducen
CN VII-
facial
CN VIII-
vestibulocochlear (auditory, vestibular)
CN IX-
glosspharyngeal
CN X-
vagus
CN XI-
spinal accessory
CN XII-
hypoglossal
Dorsal surface of the Brainstem- features
~Gracile & cuneate tubercles ~Cerebellar peduncles ~Rhomboid fossa (4th ventricle) & obex ~CN IV ~Corpora Quadrigemina (Superior & Inferior Colliculi)
Corpora Quadrigemina
~four paired bodies of the bilateral inferior colliculi and the paired superior colliculi
Internal features of the Medulla
~the CN nuclei is more dorsal with the motor nuclei more medial and the sensory nuclei more lateral
~along the ventral area we have the inferior olivary nucleus more ventromedial
~pyramidal tracts is more ventromedial (there are other motor tracts more dorsal medial)
~sensory tracts intermediate both lateral and medial
~reticular formation- the areas of intermediate medulla that is not a nucleus or tract
~inferior cerebellar peduncle dorsolaterally which is composed mostly of axons form the spinal cord and medulla entering the cerebellum
~4th ventricle on the dorsal surface between the medulla and cerebellum
Internal features of Pons
~CN are more dorsally CN nuclei with motor nuclei more medially and the sensory more laterally and pontine nuclei more ventral dispersed
~Descending motor tracts tend to be more medial and more ventral
~Ascending sensory tracts more dorsolateral
~middle cerebellar peduncle is most laterally
~reticular formation is dorsal and medial
~4th ventricle is boarded by the reticular formation
Internal features of the midbrain (how many parts)
~tectum
~tegmentum
~cerebral peduncle
Internal features of the Tectum
~composed of the corpora quadrigemina (bilateral inferior collicul and paired superior colliculi)
Internal features of the tegmentum
~has a motor nuclei which is medial both dorsal and ventral
~only a single sensory nucleus, which is more lateral
~contains reticular formation dorsal laterally
~Cerebral aqueduct is centrally positioned and is surrounded by nuclear area (periaqueductal gray)
Internal features of cerebral peduncles
~sometimes called crus cerebri
~is a prominent motor pathway from the cerebrum to brainstem and spinal cord
The cerebellum is located ____ to the brainstem and 4th ventricle
dorsal
The cerebellum is connected to the brainstem via
3 sets of paired cerebellar peduncles (superior, middle, and inferior)
what are the two major regions of the cerebellum?
~the single midline vermis
~the more lateral bilateral cerebellar hemispheres
what are the three major functional regions of the cerebellum?
~archicerebellum or vesitulocerebellum
~paleocerebellum or spinocerebellum
~neocerebellum or pontocerebellum
archicerebellum or vesitulocerebellum of cerebellum
~located on the inferior surface of the vermis in what is called the Flocculonodular lobe
~this lobe is composed of the Flocculus of paravermal area and the nodule of vermis
paleocerebellum or spinocerebellum of cerebellum
~located in the remaining vermis and paravermis area
neocerebellum or pontocerebellum of cerebellum
~located in lateral cerebellar hemisphere
~receives its inputs primarily rom the cerebral cortex via the pontine nuclei and pontocerebellar fibers
The primary input and output of the archicerebellum or vesitulocerebellum are with
the vestibular system of the brainstem
The primary input to the paleocerebellum or spinocerebellum come from
the spinal cord