2.25 Motor SC 4 Flashcards
pathological reflexes
- Babinski
- flexion
- clasp-knife
- clonus
Where do UMNs come from?
- either cortex or brainstem
- travel down to spinal cord to segment they innervate where they synapse with either interneurons or LMN
medial UMN tracts modulate
voluntary movements
medial UMN tracts
- reticulospinal
- medial vestibulospinal
- lateral vestibulospinal
- medial corticospinal aka anterior corticospinal tract
reticulospinal tract
- bilateral LMN innervating postural and gross limb movement
- coordination of all limbs while walking
- anticipatory postural adjustments
reticulospinal begins here
reticular formation of brainstem
medial vestibulospinal tract
- receives info from vestibular apparatus in the ear
- efferent starts in upper medulla and projects to cervical and thoracic spine
- controls neck and upper back muscles
lateral vestibulospinal
- receive info from vestibular apparatus in the ear
- efferent facilitates LMNs to extensors
How does the lateral vestibulospinal facilitate LMNs to extensors?
keeps COG over base of support
medial corticospinal AKA anterior corticospinal tract
- direct connection from cerebral cortex to spinal cord
- begins in motor cortex, travels to spinal cord through medullary pyramids (brainstem)
medial corticospinal tract decussation
does not cross
- innervates LMNs to ipsilateral neck, shoulder, and trunk
- descends in ventral funiculus
most important pathway controlling voluntary movements
lateral UMNs
Path of voluntary movements begin in cortex in motor planning areas. Where does it go from here?
- axons travel in internal capsule and cerebral peduncles
- through pons/medulla (in medullary pyramids)
- cross at pyramidal decussation
- synapse with LMN on opposite side
arrangement of corticospinal tracts
somatotopically arranged
tract that allows you to get information through cranial nerves into face
corticospinal brainstem tracts (corticobulbar tracts)
corticobulbar go here
- begin in motor homunculus
- through brainstem through cranial nerves to face
corticobulbar tracts important for
facial expression, swallowing, chewing, talking, etc.
