Physiology of Motor Systems Flashcards
Where is the primary motor cortex located?
located in the precentral gyrus of the frontal lobe of each hemisphere
Describe pyramidal cells
- located in the gyri
- allow us to consciously control the precise or skilled voluntary movements of our skeletal muscles.
What is anterior to the precentral gyrus in the frontal lobe
Premotor cortex
Role of premotor cortex
- helps plan and coordinate movements
- control voluntary actions that depend on sensory feedback
What Lies anterior to the inferior region of the premotor area
Broca’s area
In which area is Broca’s area usually present in
left
What is the role of Broca’s area?
- motor speech area that directs the muscles involved in speech production
What is Located partially in and anterior to the premotor cortex and superior to Broca’s area
Frontal eye field
The descending pathways that deliver efferent impulses from the brain to the spinal cord are divided into two groups:
(1) Direct pathways, which are the pyramidal tracts
(2) Indirect pathways, essentially all others
Motor pathways involve two neurons:
- Upper motor neurons are the pyramidal cells of the motor cortex and the neurons of subcortical motor nuclei
- Lower motor neurons are the ventral horn motor neurons. These directly innervate the skeletal muscles (their effectors)
The direct pathways originate mainly with the pyramidal cells located where
in the precentral gyri
neurons of the direct pathway send impulses through the brain stem via the large …
pyramidal (corticospinal) tracts
What does the pyramidal pathway regulate?
- regulates fast and fine (or skilled) voluntary movements such as texting or playing an instrument
The indirect pathways includes what?
brain stem motor nuclei and all motor pathways except the pyramidal pathways.
The indirect pathway is most involved in regulating…
- Axial muscles that maintain balance and posture
- Muscles controlling coarse limb movements
- Head, neck, and eye movements that follow objects in the visual field
Rubrospinal tracts role
control flexor muscles