Formative Flashcards
Spinal tracts are broadly divided into which two categories?
- Ascending.
- Descending.
Descending spinal tracts are divided into which two categories?
- Extrapyramidal.
- Pyramidal.
Pyramidal tracts are divided into which two categories?
- Corticospinal.
- Corticobulbar.
Origin of the corticospinal tract?
Primary motor cortex in precentral gyrus.
Corticospinal tract made up of which two parts?
- Lateral corticospinal.
- Anterior corticospinal.
Describe decussation of lateral corticospinal tract.
Pyramidal decussation.
Describe decussation of anterior corticospinal tract.
Segmental decussation.
Function of lateral corticospinal tract?
- Voluntary motor control of limbs and digits.
Function of anterior corticospinal tract?
- Voluntary motor control of trunk and maintenance of posture.
Origin of corticobulbar tracts?
Primary motor cortex of precentral gyrus.
Function of corticobulbar tracts?
- Control of muscles of face, head and neck (contains UMNs of CNs).
Corticobulbar tracts are responsible for bilateral innervation to CN nuclei, with the exception of?
- CN XII (hypoglossal).
- Lower part of CN VII (facial).
A peripheral lesion of CN VII will cause what condition with what signs?
Bell’s palsy.
- NO forehead sparing.
- > Forehead and lip droop.
A central lesion of CN VII will cause what signs, and may be caused by what condition?
Stroke.
- Forehead sparing.
- > Lip droop.
What are the two categories of extrapyramidal tracts?
- Rubrospinal tract.
- Reticulospinal tract.