week 3- brain stem

Question 1

Somatotopicorganization within the internal capsule

Answer 1

corticobulbar (motor cortex to brainstem)

corticospinal (motor cortex to spinal cord)

• UMN axons that control LMNs innervating muscles of the face are located at the genu of the internal capsule
• UMN axons that control LMNs innervating muscles of the lower extremity are located in the posterior portion of the posterior limb of the internal capsule

Question 2

what portion of the midbrain are the tectum and the cerebral peduncles located

Answer 2

Tectum - contains the pretectal area and the tectospinal tracts - dorsal/posterior

cerebral peduncles- ventral/ anterior

Question 3

what slice is this

Answer 3

midbrain

Question 4

where are the conlliculi located

Answer 4

midbrain

Question 5

where are the medullary pyramids located and what resides in them

Answer 5

internal medulla

corticospinal tract axons

Question 6

ID the three main areas of the spinal cord

how is the architecture seperated

Answer 6

posterior (dorsal) - sensory

lateral- corticospinal tract (motor)

anterolateral system - other motor tracts

The spinal gray matter can be described as a series of layers, or lamina, often with different functions.

Question 7

what is a fundiculus

Answer 7

a region of white matter where tracts travel

•(iebundles of related axons)

Question 8

what are areas that the ascending tracts can go to

descending?

Answer 8

Ascending tracts:

• thalamus, brainstem relay nuclei, cerebellum

Descending tracts:

• (UMNS) from Cortex, Brainstem, Descending modulation of sensory input