[HISTO] BRAINSTEM Flashcards
central canal still found in
closed medulla
central canal replaced by 4th ventricle in
open medulla
rostral part of medulla
open medulla
caudal part of medulla
closed medulla
pyramidal decussation of medulla
corticospinal decussation
sensory decussation of medulla
internal arcuate fibers (medial lemniscus, G&C)
spinal nucleus of trigeminal replaces
substantia gelatinosa
descending spinal trigeminal tract replaces
Lissaure’s tract
core of medulla is formed by
RF
internal features of medulla (6)
1-pyramidal decussation
2-sensory decussation
3-V spinal nucleus replaces substantia gelatinosa
4- V spinal tract replaces Lissaure’s tract
5- 4th ventricle appearance
6-RF forms core of medulla
2% of corticospinal fibers descend in
anterolateral funiculus
90% of corticospinal fibers descend in
lateral funiculus
90% of corticospinal fibers form
lateral corticospinal tracts
2% of corticospinal fibers form
anterolateral corticospinal tracts
8% of corticospinal fibers form
anterior corticospinal tract
function of motor decussation
voluntary motor control by contralateral cortex
G&C nuclei location?
G&C tract location?
dorsal aspect of medulla
posterior to nuclei
course of sensory decussation
myelinated fibers join to form internal arcuate fibers–>decussate & ascend–>medial lemniscus>VPLN
Gracile= MEDIAL
sacral= ANTERIOR
Cuneate= LATERAL
cervical=POSTERIOR
nuclei of medulla
9-12th nuclei
accessory cuneate nuclei
arcuate nuclei
olivary nuclear complex
RF nuclei
accessory cuneate nucleus site
lateral to cuneate n
arcuate nucleus site
anterior aspect of pyramid
arcuate nuclei represents
caudally displaced pontine nucleui
accessory cuneate receives fibers from?
sends fibers to?
cervical & thoracic spinal ganglia
ipsilateral cerebellum
accessory cuneate nucleus forms
dorsal external arcuate fibers (cuneaocerebellar)
arcuate nucleus fibers form
anterior external arcuate fibers
dorsal external arcuate fibers
accessory cuneate fibers
anterior external arcuate fibers
arcuate fibers
function of accessory cuneate nucleus
unconscious proprioception of UL & neck
nucleus which is equivalent to Clarke’s nucleus
accessory cuneate nucleus
arcuate nucleus function
receives afferents from cortex, sends to cerebellum
trigeminal spinal nucleus site
medial to tract
trigeminal spinal nucleus afferents
from trigeminal spinal tract
spinal trigeminal tract originates from
trigeminal spinal ganglion
trigeminal spinal tract terminates in
trigeminal spinal nucleus
function of spinal trigeminal tract + nucleus
carry pain + temp of face & mucous membranes of face
course of spinal trigeminal tract
originates from trigeminal spinal ganglion–>cross and ascend as trigeminal leminscus—> VPMN–>cortex
types of arcuate fibers in closed medulla
internal arcuate
anterior external arcuate
dorsal external arcuate
RF controls
muscle activity
somatic + visceral sensations
autonomic + endocrine nervous systems
arousal + consciousness
lesion of RF leads to
loss of consciousness & death
lesion of RF leads to
loss of consciousness & death
internal features of open medulla
Hypoglossal trigone
Vagal trigone
appearance of 4th ventricle
appearance of ICP
appearance inferior olivary complex
RF afferents
spinal cord
cortex
DCNs
RF efferents
ascending: central tegmental–> thalamus
descending: reticulospinal–>spinal cord
inferior olivary complex consists of
principal inf olivary nucleus
medial accessory nucleus
dorsal accessory nucleus
inferior olivary complex afferents
cortex
spinal cord
red nucleus
BS: vestibular nucleus+ spinal of V
inferior olivary efferent
olivocerebellar–> cerebellum
via ICP
end as climbing fibers= (+)purkinje
olivocerebellar fibers function
motor learning
afferents of ICP (7)
posterior spinocerebellar
cuneocerebellar
anterior external arcuate
vestibulo-cerebellar
reticulo-cerebellar
olivo-cerebellar
para-olivo-cerebellar
