Lecture 5- motor control (Direct and indirect activation pathways;U Flashcards
What are the 3 stages of motor learning?
planning, programming, and execution
The corticobulbar tract is _______, whereas the corticospinal tract is ______.
Bilaterally; mostly contralateral
What is the pathway of the corticospinal tract?
Motor cortex –> UMN synapses with LMN; LMN sends signals down the spinal cord via spinal nerves —-> spinal nerves innervate the skeletal muscles
Where in the brain are the UMNs located?
in the motor cortex
Where in the brain are the LMNs located?
in the CNS
LMN axons leave the CNS through _______.
spinal nerves
The left ventral motor area is also known as
Broca’s area
The lateral corticospinal tract innervates ____
muscles in the limbs
The anterior corticospinal tract innervates _____
muscles of the trunk
In the lateral corticospinal tract, where do the UMN axons decussate?
at the caudal medulla or pyramids of the medulla
What areas of the brain does the motor impulses go through on the lateral corticospinal tract to innervate a muscle?
motor strip —- > UMN —> internal capsule—-> midbrain —-> pons —-> rostral medualla —- caudal medulla —-> LMN —– spinal cord
What is the purpose of the corticospinal tract?
it carries motor impulses from the pre-central gyrus to the skeletal muscles
What is the pathway of the anterior corticospinal tract that the motor impulses pass through?
motor strip –> UMN –> internal capsule —> midbrain –> pons –> rostral medulla –> LMN—> spinal cord
UMNs in the corticobulbar tract end in the ______
brainstem
What are the four indirect pathways of the motor cortex?
rubrospinal, reticulospinal, vestibulospinal, and tectospinal
What are general symptoms of lesions to the indirect pathway?
postural imbalance, increased stretch reflex, spasticity, hypertonus