Brain stem- tracts and nuclei

Question 1

What separates the crura from the tegmentum?

Answer 1

Substansia nigrae

Question 2

What does the substansia nigra consist of?

Answer 2

Pars compacta (medially), pars reticulata (laterally)

Question 3

What does pars compacta produce?

Answer 3

Dopamine

Question 4

What does pars reticulata produce?

Answer 4

GABA

Question 5

Where is the oculomotor nucleus located?

Answer 5

Adjacent to periaqueductal grey matter

Question 6

What is role of pretectal nuclei?

Answer 6

plays key role in pupillary light reflex

Question 7

Where is trochlear nerve nucleus located?

Answer 7

Anterior to periaqueductal grey matter in lower midbrain

Question 8

What is the key recognisable feature in the lower midbrain?

Answer 8

The dentato-rubro-thalamo-cortical pathway

Question 9

What is the anterior convexity of the pons caused by?

Answer 9

The decussation of corticopontine fibres

Question 10

Where are the nuclei of the facial and abducent nerve located?

Answer 10

The pons

Question 11

What are the abducent and oculomotor nuclei controlled by?

Answer 11

Pattern generator cells

Question 12

Where do the medial and lateral vestibulospinal tracts originate?

Answer 12

Vestibular nucleus in the pons and upper medulla

Question 13

What lies at the level of the pontomedullary junction?

Answer 13

The nuclei associated with vestibulocochlear and glossopharyngeal nerves

Question 14

What is the function of the medial longitudinal fasciculus?

Answer 14

To execute head turning movements in response to saccadic, optokinetic and vestibulo-ocular reflexes

Question 15

What is located in the anterior wall of the fourth ventricle?

Answer 15

The hypoglossal, dorsal vagal and vestibular nuclei

Question 16

Where do the corticospinal tracts decussate?

Answer 16

The lower medulla

Question 17

Where does the corticospinal pathway descend from?

Answer 17

The posterior limb of the internal capsule

Question 18

Where do the corticospinal fibres pass through?

Answer 18

Middle three fifths of crus

Question 19

Where do the frontopontine fibres occupy?

Answer 19

Medial fifth of each crus

Question 20

Where do temporopontine fibres occupy?

Answer 20

Lateral fifth of each crus

Question 21

What are frontopontine involved in?

Answer 21

Part of extrapyramidal pathway and control functions such as movement of eyes

Question 22

Where do the temperopontine fibres terminate?

Answer 22

The cerebellum

Question 23

What fibres run through the tegmentum?

Answer 23

Medial, spinal and trigeminal lemnisci

Question 24

What gives the red nucleus its colour?

Answer 24

Its store of iron

Question 25

Where do fibres from the ventral cochlear nuclei decussate?

Answer 25

The trapezoid body

Question 26

What is function of vestibular nuclei?

Answer 26

Receive input from the semicircular canals and link with vestibulocerebellum to control posture

Question 27

What is function of lateral vestibulospinal tract?

Answer 27

Contracts extensor muscles of legs thereby maintaining core balance

Question 28

Where is nucleus ambiguus located?

Answer 28

Upper medulla

Question 29

Where do corticospinal tracts decussate?

Answer 29

In the lower medulla

Question 30

What does the respiratory centre consist of?

Answer 30

2 nuclei in pons and 2 nuclei in medulla