Medulla

Question 1

Where is the medulla located?

Answer 1

Between the pons and the spinal cord.

Question 2

What is the length of the medulla?

Answer 2

Approximately 3 cm.

Question 3

What cavity does the dorsal medulla form part of?

Answer 3

The floor of the fourth ventricle.

Question 4

At what level does the medulla transition to the spinal cord?

Answer 4

At the foramen magnum.

Question 5

What is the primary function of the medulla?

Answer 5

Regulates autonomic functions like breathing, heart rate, and blood pressure.

Question 6

Which cranial nerves are associated with the medulla?

Answer 6

Cranial nerves IX, X, XI, and XII.

Question 7

What arteries supply blood to the medulla?

Answer 7

Anterior spinal artery, vertebral arteries, and posterior inferior cerebellar artery (PICA).

Question 8

What happens when the posterior inferior cerebellar artery (PICA) is occluded?

Answer 8

Lateral medullary syndrome (Wallenberg syndrome) occurs.

Question 9

Which autonomic centres are located in the medulla?

Answer 9

The cardiac, respiratory, and vasomotor centres.

Question 10

What is the clinical significance of the pyramidal decussation in the medulla?

Answer 10

It is the site where corticospinal tracts cross, leading to contralateral motor control.

Question 11

What are the pyramids on the anterior surface of the medulla?

Answer 11

Longitudinal ridges formed by corticospinal tracts.

Question 12

What is the olive on the ventrolateral surface of the medulla?

Answer 12

A bulge formed by the inferior olivary nucleus.

Question 13

What structure lies in the midline of the ventral medulla?

Answer 13

The anterior median fissure.

Question 14

What is the pyramidal decussation?

Answer 14

The crossing of corticospinal tracts at the lower medulla.

Question 15

What are the gracile and cuneate tubercles on the dorsal medulla?

Answer 15

Elevations formed by the underlying gracile and cuneate nuclei.

Question 16

Where are the inferior cerebellar peduncles located?

Answer 16

On the dorsal-lateral aspect of the medulla.

Question 17

What separates the medulla from the pons?

Answer 17

The inferior pontine sulcus.

Question 18

What groove is located between the pyramids and the olives?

Answer 18

The preolivary sulcus.

Question 19

Which cranial nerve emerges from the preolivary sulcus?

Answer 19

The hypoglossal nerve (cranial nerve XII).

Question 20

What groove lies posterior to the olives?

Answer 20

The postolivary sulcus.

Question 21

Which cranial nerves emerge from the postolivary sulcus?

Answer 21

Cranial nerves IX, X, and XI.

Question 22

What is the role of the posterior median sulcus?

Answer 22

Divides the medulla’s dorsal surface into two symmetrical halves.

Question 23

What structure is found on the dorsal medulla near the fourth ventricle?

Answer 23

The obex.

Question 24

What does the posterior surface of the medulla form?

Answer 24

The floor of the fourth ventricle.

Question 25

What are the features of the dorsal medulla related to sensory processing?

Answer 25

Gracile and cuneate tubercles process fine touch and proprioception.

Question 26

What nuclei are found in the dorsal medulla?

Answer 26

Gracile and cuneate nuclei.

Question 27

What is the medial lemniscus?

Answer 27

A pathway transmitting fine touch and proprioception to the thalamus.

Question 28

What is the role of the hypoglossal nucleus in the medulla?

Answer 28

Controls tongue movements.

Question 29

Which nucleus controls parasympathetic output to the thoracic and abdominal viscera?

Answer 29

The dorsal motor nucleus of the vagus nerve.

Question 30

What is the function of the nucleus ambiguus?

Answer 30

Controls muscles of the pharynx and larynx via cranial nerves IX and X.

Question 31

Which nucleus processes pain and temperature sensations from the face?

Answer 31

The spinal trigeminal nucleus.

Question 32

What is the reticular formation in the medulla?

Answer 32

A network involved in autonomic regulation and consciousness.

Question 33

What is the inferior olivary nucleus, and what does it do?

Answer 33

A relay centre for motor coordination to the cerebellum.

Question 34

Which tract carries pain and temperature sensations through the medulla?

Answer 34

The spinothalamic tract.

Question 35

What happens to the corticospinal tracts in the lower medulla?

Answer 35

They decussate to the opposite side.

Question 36

What cranial nerve nucleus controls swallowing and vocalisation?

Answer 36

The nucleus ambiguus.

Question 37

What is the solitary nucleus, and what does it process?

Answer 37

It processes taste and visceral sensations.

Question 38

Which autonomic centres are housed within the medulla?

Answer 38

Cardiac, vasomotor, and respiratory centres.

Question 39

What is the role of the vestibular nuclei in the medulla?

Answer 39

Maintains balance and equilibrium.

Question 40

Which tract passes through the medial part of the medulla?

Answer 40

The corticospinal tract.