6 (C) Descending Pathway Flashcards
Corticospinal tract
Cortex –> Spinal Cord –> via ………………………..
Spinal nerves
Corticonuclear
Cortex –> …… –> via …………..
Brainstem
Cranial Nerves
Within the internal capsule, its somatotopically organised from what - what? (medial to lateral)
F A T L
What key structure is in place that the internal capsule connects to that is found in the midbrain
Cerebral peduncles (Crus cerebri)
What % of fibres decussate at pyramids
85%
from dorsal to ventral, the lateral corticospinal tract is somatotopically organised from what - what
Leg
Trunk
Arm
(from out to in)
What type of innervation is the anterior corticospinal tract?
What structure does it go down?
Bilateral
Ventral corticospinal tract (Anterior)
Which corticospinal tract is responsible for hte axial musculature (tone)
Anterior
Which corticospinal tract is responsible for limb musculature?
Lateral
Hypertonia occurs in what type of lesion? When does it occur (time) after motor function recovers
UMN Lesion
Long term
Babinski sign shows what type of lesion
UMN
The corticonuclear pathway originates from where?
Pre-central-gyrus
Innervation of LMN in corticonuclear pathway are all?
What are the exceptions (just the nerves)
Bilateral
Facial Nerve + Hypoglossal
The facial nerve is what in terms of innervation?
Which innervation is which (upper / lower)
Bilateral (upper)
Contralateral (lower)
The hypoglossal nerve has what type of innervation?
Contralateral
What are the facial nerve branches from superior to inferior?
Temporal (Tiger) Zygomatic (Zoo's) Buccal (Bore) Mandibular (me) Cervical (constantly)
A supranuclear lesion is what type of lesion? Upper or lower?
Upper
If there is a facial nerve supranuclear lesion, what occurs?
Bottom of face affected –> Contralateral to lesion
Top part unaffected –> Due to bilateral innervation
If whole half face is affected, where is the lesion?
LMN lesion
Whole of facial nerve on one side is affected
What are some symptoms of a LMN of face
-> Eyes // mouth // eyebrows
Orbicularis muscle + facial muscles affected
- > unable to close eyes
- > weakness at angle of mouth
- > cannot elevate eyebrows
if a LMN is present in hypoglossal, what side does tongue deviate
Side of lesion
If a UMN is present in hypoglossal, what side does tongue deviate?
Contralateral
Reticular formation + red nucleus are both responsible for what in terms of muscle?
Controlling muscle tone
Posture is affected by what system
Vestibular
New born spinal cord ends at what?
L3
L1 / L2
Termination of sub srachnoid space
S2
Both anterior + posterior spinal Vein drain into what?
Internal Vertebral plexus
What structurally do spinal veins not have
No valves
Ventral + dorsal rami have both motor + sensory fibres (T /F)
T
Dysphasia + Amarausis fugax are both indicative of what type of circulation being impeeded?
Anterior circulation
Ataxia + Diplopia + vertigo + bilateral symptoms are all indicative of what type of circulation being impeeded?
Posterior Circulation
Increased hyperflexia in UMN lesion occurs below or above lesion site?
Below Lesion Site
Key structure that lateral corticospinal tract goes down in midbrain
Cerebri Peduncles // Crus Cerebri
