W22-L3: Motor Cortex

Question 1

What is Decorticate rigidity?

Answer 1

extensors dominate in legs, flexors in arms

Question 2

What is Decerebrate rigidity?

Answer 2

extensors dominate everywhere

Question 3

What is the rubro-spinal tract?

Answer 3

short tract to only cervical region from red nucleus, main role is initiation of flexors

Question 4

What is the basis of Decorticate rigidity?

Answer 4

There is removal of all inhibition to brainstem, no inhibition to reticular formation or red nucleus due to disruption above red nucleus, flexors win where there is still rubro-spinal tract (i.e cervical regions)

Question 5

What is the basis of Decerebrate rigidity?

Answer 5

level of disruption below midbrain at the level of the brain stem, red nucleus is compromised

Question 6

What does a change from decorticate to decerebrate mean?

Answer 6

More damage to the brainstem

Question 7

Cortibulbar innervation of LMNs is…

Answer 7

Bilateral except to those innervating lower face and tongue

Question 8

What is the Locomotor pattern generator?

Answer 8

spinal circuit that functions to control the entire motor system