Neuroanatomy: Motor Systems

Question 1

Which parts of the CNS are involved in motor behaviors?

Answer 1

Involves entire CNS, brain, brain stem, and spinal cord

Question 1

What are the differences between somatic and visceral motor neurons?

Answer 1

Somatic carries signals to skeletal muscle, the visceral carries signals to glands, cardiac muscle, and smooth muscle.

Question 2

Where are the somatic and visceral motor neurons?

Answer 2

Visceral motor neurons are located in intermediolateral cell column. Somatic are located in Ventral horn

Question 3

Where are the upper motor neurons?

Answer 3

located in precentral gyrus

Question 4

Describe the path of the upper motor neuron axons.

Answer 4

activated by decision to move in precentral gyrus. Goes to internal capsule(anterior limb), then crus cerebri, the pons, then pyramids (medulla oblongata), then pyramidal decussation (defines border between brain stem and spinal cord), then corticospinal tracts, then muscle

Question 5

Where do the upper motor neurons synapse?

Question 6

Where are the lower motor neurons?

Question 7

What is the path of the lower motor neuron axons?

Question 8

Where do the lower motor neurons synapse?

Question 9

What are the components of the basal ganglia?

Answer 9

Includes the caudate, putamen, globus pallidus, substantia nigra, and subthalamic nucleus

Question 10

With what larger parts of the brain are the basal ganglia associated?

Answer 10

striatum, pallidum, brain stem, diencephalon

Question 11

Where are the basal ganglia in the brain

Answer 11

In the medial section of the brain

Question 12

What is the BASIC circuitry of the basal nuclei

Answer 12

Goes from thalamus up to motor cortex to striatum

Question 13

What is the difference between the direct and indirect pathways with regard to function?

Answer 13

Direct pathways facilitate appropriate motor programs whereas indirect pathways inhibit competing/unwanted motor programs

Question 14

What are basal ganglia

Answer 14

a group of neurons with the CNS that function together with common targets, input, and neurotransmitters. Are responsible for muscle memory

Question 15

Describe the Gross anatomy of the cerebellum

Answer 15

there are 2 cerebellar hemispheres; each hemisphere is split into 2 lobes, the anterior and posterior, and they are separated by the primary fissure. Also include folia and vermis which are similar to gyri and sulci respectively

Question 16

What are cerebellar peduncles

Answer 16

They are large fiber tracts that are attached to the brain stem

Question 17

How many peduncles are there and what fibers travel in each

Answer 17

there are 3 peduncles; the superior cerebellar (main outflow, project to motor cortex), middle cerebellar (fibers enter from the pons), and inferior cerebellar (fibers enter from the medulla and spinal cord)

Question 18

How many layers are in the cerebellar cortex and what are their names

Answer 18

There are 3 layers; the molecular layer, purkinje cell layer, and granule cell layer

Question 19

What type of cells are in each layer of the cerebellar cortex

Question 20

Where does information go when it leaves the cerebellar cortex

Answer 20

It goes to the motor cortex

Question 21

What is the area of the cerebellum that sends efferent information to the motor cortex?

Answer 21

Superior peduncle