Section 7, Part ?

Question 1

What is the tectum?

Answer 1

The tissue positioned above the aqueduct

Question 2

What makes up the tectum?

Answer 2

Superior colliculi and inferior colliculi

Question 3

How many colliculi are there?

Answer 3

4….2 inferior and 2 superior

Question 4

Where is the midbrain tegmentum located…ventrally or dorsally?

Answer 4

Ventrally

Question 5

What does the midbrain merge with rostrally?

Answer 5

Thalamus

Question 6

What marks the boundary between the midbrain and diencephalon?

Answer 6

Posterior Commissure (dorsally)

Question 7

What is the function of the posterior commissure?

Answer 7

Form a bridge between the Pretectal area (nuclei) of each side of the brainstem

Question 8

What overlays the posterior commissure?

Answer 8

Pineal body

Question 9

What pathology will press down no the posterior commissure? What are the diagnostic symptoms?

Answer 9

Pinealoma

First diagnositc symptom of a pinealoma is a paralysis of upward eye movements.

As the tumor grows, there is loss of pupilary light reflex (fixed, dilated pupils result), and possible hydrocephalus because obstruction of cerebral aqueduct

Question 10

What is the interstitial nucleus of Cajal involved in?

Answer 10

it is the vertical gaze center. So pathology presents as inability to look up and down

Question 11

Where is Cajal located?

Answer 11

Within the reticular formation at the rostral end of the MLF in the midbrain

Question 12

What terminates at the inferior colliculus?

Answer 12

lateral lemniscus

Question 13

Where dies the inferior colliculus send axons?

Answer 13

To the thalamus

Question 14

How does the inferior colliculus send axons to its target?

Answer 14

brachium of the inferior colliculus

Question 15

Where does the brachium of the inferior colliculus end?

Answer 15

It ends in the MGN (Medial geniculate nucleus)

Question 16

What type of information does the inferior colliculus transmit?

Answer 16

It relays auditory information from both ears to auditory cortex (Heschl’s gyrus, transverse temporal gyrus, and auditory cortex)

Question 17

Where is the medial lemniscus located?

Answer 17

Just ventral to the lateral lemnisus in the caudal part of the midbrain

Question 18

What does the medial lemniscus carry?

Answer 18

Epicritic sensory signals for the contralateral side of the body

Question 19

In the midbrain, where are anterolateral tracts found?

Answer 19

Lie between the LL and ML

Question 20

If there is a lesion involving the dprsal tegmentum in the lateral midbrain, what would the symptoms be?

Answer 20

protopathic and epicritic sensory loss from the opposite side of the body and face

Question 21

Which cerebellar peduncle deccussates at the level of the midbrain?

Answer 21

Superior cerebellar peduncle

Question 22

After the fibers of the Superior cerebellar peduncle cross, where do some end up?

Answer 22

Red Nucleus

LA and VL nucleus of the thalamus

Question 23

What does the red nucleus give rise to?

Answer 23

Brainstem- spinal motor pathway…the Rubrospinal tract

There are also some projections to the Inferior olivary complex

Some to the LA and VL nucleus of the thalamus

Question 24

Is the trochlear nucleus caudal or rostral in the midbrain?

Answer 24

Caudal

Question 25

Is the oculomotor mucleus located caudal or rostral in the midbrain?

Answer 25

rostral

Question 26

What is dorsal to the CN IV and CN III nuclei (in the tegmentum) of the midbrain?

Answer 26

periaqueductal gray